Compendium | December 2009 by davidpsu

Compendium CompendiumVet.com | Peer Reviewed | Listed in MEDLINE

Vacuum Therapy for Wound Healing Feline Focus Causes of Upper Respiratory Signs in Cats

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Vol 31(12) December 2009

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EXECUTIVE EDITOR Tracey L. Giannouris, MA 800-426-9119, ext 52447 | tgiannouris@vetlearn.com Online Subscription inquiries: Visit Vetlearn.com or call 800-426-9119, option 2. Indexing: Compendium: Continuing Education for Veterinarians® is included in the international indexing coverage of Current Contents/ Agriculture, Biology and Environmental Sciences (ISI); SciSearch (ISI); Research Alert (ISI); Focus On: Veterinary Science and Medicine (ISI); Index Veterinarius (CAB International, CAB Abstracts, CAB Health); and Agricola (Library of Congress). Article retrieval systems include The Genuine Article (ISI), The Copyright Clearance Center, Inc., University Microfilms International, and Source One (Knight-Ridder Information, Inc.). Yearly author and subject indexes for Compendium are published each December.

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Published monthly by Veterinary Learning Systems, a division of MediMedia, 780 Township Line Road, Yardley, PA 19067. Copyright © 2009 Veterinary Learning Systems. All rights reserved. Printed in the USA. No part of this issue may be reproduced in any form by any means without prior written permission of the publisher. Printed on acid-free paper, effective with volume 29, issue 5, 2007. Periodicals postage paid at Morrisville, PA, and at additional mailing offices. Postmaster: Canada Post international publications mail product (Canadian distribution) sales agreement no. 40014103. Return undeliverable Canadian addresses to MediMedia, PO Box 7224, Windsor, ON N9A 0B1. Printed in USA.

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EDITORIAL BOARD Anesthesia Nora S. Matthews, DVM, DACVA Texas A&M University

Internal Medicine Dana G. Allen, DVM, MSc, DACVIM Ontario Veterinary College

Cardiology Bruce Keene, DVM, MSc, DACVIM North Carolina State University

Internal Medicine and Emergency/ Critical Care Alison R. Gaynor, DVM, DACVIM (Internal Medicine), DACVECC North Grafton, Massachusetts

Clinical Chemistry, Hematology, and Urinalysis Betsy Welles, DVM, PhD, DACVP Auburn University

EDITOR IN CHIEF Douglass K. Macintire, DVM, MS, DACVIM, DACVECC

Department of Clinical Sciences College of Veterinary Medicine Auburn University, AL 36849

EXECUTIVE ADVISORY BOARD MEMBERS

Dentistry Gary B. Beard, DVM, DAVDC Auburn University R. Michael Peak, DVM, DAVDC The Pet Dentist—Tampa Bay Veterinary Dentistry Largo, Florida Emergency/Critical Care and Respiratory Medicine Lesley King, MVB, MRCVS, DACVECC, DACVIM University of Pennsylvania Endocrinology and Metabolic Disorders Marie E. Kerl, DVM, DACVIM, DACVECC University of Missouri-Columbia

Behavior Sharon L. Crowell-Davis, DVM, PhD, DACVB The University of Georgia

Epidemiology Philip H. Kass, DVM, MPVM, MS, PhD, DACVPM University of California, Davis

Dermatology Craig E. Grifﬁn, DVM, DACVD Animal Dermatology Clinic San Diego, California

Exotics Avian Thomas N. Tully, Jr, DVM, MS, DABVP (Avian), ECAMS Louisiana State University

Wayne S. Rosenkrantz, DVM, DACVD Animal Dermatology Clinic Tustin, California Feline Medicine Margie Scherk, DVM, DABVP (Feline Medicine) Cats Only Veterinary Clinic Vancouver, British Columbia Nutrition Kathryn E. Michel, DVM, MS, DACVN University of Pennsylvania Surgery Elizabeth M. Hardie, DVM, PhD, DACVS North Carolina State University

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Reptiles Douglas R. Mader, MS, DVM, DABVP (DC) Marathon Veterinary Hospital Marathon, Florida Small Mammals Karen Rosenthal, DVM, MS, DABVP (Avian) University of Pennsylvania Feline Medicine Michael R. Lappin, DVM, PhD, DACVIM (Internal Medicine) Colorado State University

Nephrology Catherine E. Langston, DVM, DACVIM Animal Medical Center New York, New York Neurology Curtis W. Dewey, DVM, MS, DACVIM (Neurology), DACVS Cornell University Hospital for Animals Oncology Ann E. Hohenhaus, DVM, DACVIM (Oncology and Internal Medicine) Animal Medical Center New York, New York Gregory K. Ogilvie, DVM, DACVIM (Internal Medicine, Oncology), DECVIM-CA (Oncology) CVS Angel Care Cancer Center and Special Care Foundation for Companion Animals Carlsbad, California Ophthalmology David A. Wilkie, DVM, MS, DACVO The Ohio State University Parasitology Byron L. Blagburn, MS, PhD Auburn University David S. Lindsay, PhD Virginia Polytechnic Institute and State University Pharmacology Katrina L. Mealey, DVM, PhD, DACVIM, DACVCP Washington State University Rehabilitation and Physical Therapy Darryl Millis, MS, DVM, DACVS University of Tennessee Surgery Philipp Mayhew, BVM&S, MRCVS, DACVS Columbia River Veterinary Specialists Vancouver, Washington

Gastroenterology Debra L. Zoran, DVM, MS, PhD, DACVIM (Internal Medicine) Texas A&M University

C. Thomas Nelson, DVM Animal Medical Center Anniston, Alabama

Infectious Disease Derek P. Burney, DVM, PhD, DACVIM Gulf Coast Veterinary Specialists Houston, Texas

Toxicology Tina Wismer, DVM, DABVT, DABT ASPCA National Animal Poison Control Center Urbana, Illinois

AMERICAN BOARD OF VETERINARY PRACTITIONERS (ABVP) REVIEW BOARD Kurt Blaicher, DVM, DABVP (Canine/Feline) Plainﬁeld Animal Hospital Plainﬁeld, New Jersey Canine and Feline Medicine Eric Chafetz, DVM, DABVP (Canine/Feline) Vienna Animal Hospital Vienna, Virginia Canine and Feline Medicine Henry E. Childers, DVM, DABVP (Canine/Feline) Cranston Animal Hospital Cranston, Rhode Island Canine and Feline Medicine John G. DeVries, DVM, DABVP (Canine/Feline) Oradell Animal Hospital Paramus, New Jersey Canine and Feline Medicine David E. Harling, DVM, DABVP (Canine/Feline), DACVO Reidsville Veterinary Hospital Reidsville, North Carolina Canine and Feline Medicine, Ophthalmology Jeffrey Katuna, DVM, DABVP Wellesley-Natick Veterinary Hospital Natick, Massachusetts Canine and Feline Medicine Robert J. Neunzig, DVM, DABVP (Canine/Feline) The Pet Hospital Bessemer City, North Carolina Canine and Feline Medicine

Compendium is a refereed journal. Articles published herein have been reviewed by at least two academic experts on the respective topic and by an ABVP practitioner. Any statements, claims, or product endorsements made in Compendium are solely the opinions of our authors and advertisers and do not necessarily reﬂect the views of the Publisher or Editorial Board.

The Editor’s Desk ❯❯ Douglass K. Macintire Editor in Chief, Compendium

Taking It Digital in 2010…

hat’s right—we’re going digital (and green) in 2010! What does this mean, you ask? Well, for starters, it means that Compendium: Continuing Education for Veterinarians® will be published monthly online at our new Vetlearn.com site. The journal will continue to be peer reviewed and Medline indexed and provide the highest-caliber quality content that you have known and trusted for more than 30 years.

Register and update your profile today at Vetlearn.com for free access! And here’s the exciting part of our transition: digital gives you more—more content; more CE; more peer-to-peer interaction, including instructional step-by-step videos; Q&A forums with key opinion leaders and experts in the field; practice management analytic tools; and an online veterinary community—all in one central location and backed by our editorial team and advisory board of experts. All of us here at Compendium and Vetlearn.com are committed to meeting the growing education and practice management needs of you, our readers, and are energized about our new online presence at Vetlearn.com. December will be your last print issue, so I urge you to go online today and register or update your profile at Vetlearn. com. All veterinary professionals can sign up for FREE. I wish you a safe, healthy, and happy holiday season and look forward to seeing you online in 2010!

The simple truth:

A microchip system should provide easy 24/7 online access. The answer to microchipping is resQ®. We make it easy with free registration, no annual fees, 24/7 access, and compliance with recommended ISO standards. s. Your simple solution:

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Douglass K. Macintire, DVM, MS, DACVIM, DACVECC Editor in Chief, Compendium

Vetlearn.com | December 2009 | Compendium

www.PetLink.NET

© 2009 Bayer HealthCare LLC, Animal Health Division, Shawnee Mission, Kansas 66201 Q are registered trademarks of Bayer Bayer, the Bayer Cross and resQ Bayer. PetLink and design are trademarks of Datamars S.A.

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December 2009 Vol 31(12)

E Each CE article is accredited for 3 contact hours by A Auburn University College of Veterinary Medicine.

Features Vetlearn.com | Peer Reviewed | Listed in MEDLINE

554 Feline Focus Update on Feline Upper Respiratory Diseases: Introduction and Diagnostics

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Feline Struvite Urolithiasis

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❯❯ Douglas Palma, Cathy Langston, CE Kelly Gisselman, and John McCue This article continues a series on the diagnosis and treatment of different types of uroliths.

❯❯ Jessica Quimby and Michael R. Lappin In this article, the authors describe a threephase diagnostic workup for establishing the cause of sneezing, nasal discharge, and other common signs of upper respiratory disease in cats. A companion article detailing treatment options for feline upper respiratory diseases will be published online in January 2010. FREE

568 Surgical Views CE Vacuum-Assisted Wound dC Closure: l Application and Mechanism of Action ❯❯ Kristin A. Kirkby, Jason L. Wheeler, James P. Farese, Gary W. Ellison, Nicholas J. Bacon, Colin W. Sereda, and Daniel D. Lewis Vacuum-assisted closure (VAC) therapy can help promote healing in many types of wounds. This article discusses the equipment necessary for VAC therapy and its use. A companion article describing clinical applications of VAC therapy will be published online in March 2010.

Jessica Quimby performs a detailed examination of the head and neck of a cat with upper respiratory disease, as described on page 558.

566 Vetlearn.com 577 Index to Advertisers 578 Market Showcase 578 Classiﬁed Advertising 579 Client Handout: Feline Upper Airway Infections

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Compendium: Continuing Education for Veterinarians

Canadian News

Coming Events January 28–30 OVMA 2010 Conference and Trade Show Westin Harbour Castle, Toronto, Ontario This 3-day conference will include CE, wet labs, master classes, and clinical pearls. Phone 800-670-1702 Web ovma.org February 3 Ottawa Academy of Veterinary Medicine: Ophthalmology Embassy West Hotel and Conference Center, Ottawa, Ontario This seminar will review ophthalmologic topics and be presented by Dr. Chantal Pinard. Web oavm.org February 10 Calgary Academy of Veterinary Medicine: Exotics Clara Christie Theatre, Health Sciences, University of Calgary, Alberta This seminar will offer 1.5 hours of scientific CE and be presented by Dr. Dennilyn Parker. Phone 403-863-7160 E-mail info@cavm.ab.ca Web cavm.ab.ca/ce_calendar.html February 24 Ontario Veterinary Medical Association: Peri-operative Pain Management Holiday Inn, Kitchener, Ontario This seminar, part of the Golden Triangle Veterinary Academy series, will be presented by Dr. Nancy Brock. Phone 519.662.3899 Web ovma.org March 11 Ontario Veterinary Medical Association: Surgical Techniques in Critical Care Embassy West Hotel and Conference Center, Ottawa, Ontario This seminar will cover emergency management techniques, such as those for acute, severe hemorrhage and orthopedic emergencies. It will be presented by Drs. Carl Porter and Mike Ethier. Phone 519.662.3899 Web ovma.org March 21 Calgary Academy of Veterinary Medicine: Dermatology Clara Christie Theatre, Health Sciences, University of Calgary, Alberta This seminar will offer 6 hours of scientific CE and be presented by Dr. Anthony Yu. Phone 403-863-7160 E-mail info@cavm.ab.ca Web cavm.ab.ca/ce_calendar.html May 23 Lifelearn Inc. LIVE Courses: Practice Management Ontario Veterinary College University of Guelph, Ontario In this seminar, Drs. Jim Stowe and Steve Noonan will discuss practice management techniques and how to find the ideal balance for your practice. Phone 800-375-7994 Web www.lifelearn.com

Atlantic Veterinary College Reopens Teaching Hospital

he Atlantic Veterinary College recently reopened its teaching hospital after an extensive renovation and expansion. The completion of these projects will beneﬁt students as well as the patients served by the institution. The renovation improved approximately 10,000 square feet of space and included an increase in the number of surgery rooms; an expanded anaesthesia, induction, and recovery

area; an intensive care unit and isolation ward; a family consultation room; clinical conference space; rooms dedicated to dentistry, special procedures, and exotic animals; and an improved bovine loading area. The hospital held a celebration in honor of the reopening that included a tour of the new and expanded facilities as well as demonstrations by the hospital staff.

OVC Professor Receives Award

rofessor Alicia Viloria-Petit, a faculty member and investigator at Ontario Veterinary College’s (OVC’s) new Institute for Comparative Cancer Investigation, has been named the 2009 winner of the prestigious Jennifer Dorrington Award from the Banting Research Foundation, Canada’s oldest medical research institute. Dr. ViloriaPetit was also one of ﬁve Canadian researchers to receive a 2009 Banting Research Foundation award. The Jennifer Dorrington Award is given to the highest-ranked applicant in the ﬁeld of cancer or reproductive biology and includes a $20,000 prize. The

award is a tribute to Jennifer Dorrington, who chaired the Banting Foundation’s grant review panel from 1995 to 1996, for her accomplishments in reproductive biology and ovarian cancer. Dr. Viloria-Petit studies how cells change from a normal site-restrained state to a migratory state, a fundamental process in cancer metastasis. “I hope to develop these studies into a larger research program aimed at understanding how breast cancer progresses to metastatic disease,” says Dr. ViloriaPetit. “My ultimate goal is to contribute new ideas for more effective treatments of advanced breast cancer.”

SPREAD YOUR GOOD NEWS ONLINE! Have any interesting news to share? Post it on the new Vetlearn.com! In 2010, we will be launching a new interactive forum where veterinarians can share their news and discuss current issues. Register for free at Vetlearn.com today!

Vetlearn.com | December 2009 | Compendium: Continuing Education for Veterinarians®

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CE Article 1

3 CE CREDITS

Feline Struvite Urolithiasis ❯❯ Douglas Palma, DVM ❯❯ Cathy Langston, DVM, DACVIM (Small Animal Internal Medicine) ❯❯ Kelly Gisselman, DVM ❯❯ John McCue, DVM Animal Medical Center New York

Abstract: Feline urolithiasis represents 15% of all cases of nonobstructive lower urinary tract disease in cats. Approximately 50% of feline uroliths are composed of struvite. Struvite urolithiasis commonly recurs, but optimal management may decrease its frequency. The pathophysiology and management of struvite urolithiasis are different in cats and dogs. This article focuses on struvite urolithiasis in cats, highlighting important aspects of pathophysiology, treatment, and prevention.

Pathophysiology

At a Glance Pathophysiology Page 542

Signalment Page 543

Incidence Page 547

Diagnosis Page 547

Treatment Page 547

Monitoring Page 550

Prevention Page 552

MORE ON THE WEB Calcium Oxalate Urolithiasis (November 2009) Urate Urolithiasis (October 2009) Diagnosis of Urolithiasis (August 2008)

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The pathophysiology of struvite urolithiasis is different from that of other forms of urolithiasis. In general, the factors that influence the formation of a calculus include urine pH, renal mineral excretion, the presence of promoters, the absence of inhibitors, and the presence of infection or inflammation. In struvite urolithiasis, the concentration of struvite crystals free to react with other solutes in a solution, called the struvite activity product (SAP), also influences calculus formation. When the SAP increases to the point at which the urine becomes supersaturated, the crystals aggregate, forming uroliths. With further increases in SAP, spontaneous crystallization can occur.1 Most canine struvite uroliths are caused by urinary tract infections. However, struvite uroliths are sterile in approximately 95% of feline cases. In cats, the formation of struvite uroliths is influenced by metabolic factors, including urine concentration, pH, and excess consumption or excretion of calculogenic minerals.2 An epidemiologic study3 that evaluated dietary risk factors for struvite and calcium oxalate urolithiasis found that increased magnesium, phosphorus, calcium, chloride, and fiber concentrations favored

Compendium: Continuing Education for Veterinarians® | December 2009 | Vetlearn.com

struvite formation in cats with existing urolithiasis compared with control animals without urolithiasis. As dietary fat content increased, struvite urolith formation was reduced. However, the interactions of minerals within the body may be more important than individual factors in altering the formation of struvite uroliths.3 It has been suggested that the dietary protein source may alter nitrogenous waste production, urinary acidification, and struvite formation. Additionally, protein may provide organic material that can act as a nidus for stone formation.4 Natural inhibitors such as citrate may reduce relative urinary supersaturation with struvite, similar to their suggested mechanism for reducing calcium oxalate formation.5 Urinary pH is the most important factor in determining the SAP. Acidification of urine causes deprotonation of phosphates and increases the total proportion of urine phosphate existing as trivalent anions, reducing the SAP.6 Urinary pH and SAP have been reduced with both dietary modification and administration of urinary acidifiers.7 The solubility of struvite is maximized when the urinary pH is <6.4.5 Other factors may contribute to struvite urolithiasis. Recently, it was shown that soluble proteins in feline urine act as pro-

FREE

Feline Struvite Urolithiasis CE FIGURE 1

FIGURE 2

Struvite crystals in urine. Note the characteristic coffin shape. (1000× magnification)

Radiograph of typical radiopaque struvite cystic calculi.

moters of struvite crystallization independent and urine concentration, respectively. Dietary of SAP.8 The authors of this study suggested moisture content has not definitively been that reducing urinary protein excretion would shown to influence struvite calculus formation be helpful in decreasing struvite crystallization in cats.3 and urolithiasis formation. Occasionally, infection can increase uri- Signalment nary ammonium concentration and pH, both There is no clear sex predilection.9,10 Although of which may contribute to struvite urolithiasis, any breed can be affected, several breeds have through urease production. Urease acts to con- an increased risk of struvite calculus formavert urea to ammonia (NH3), which, through tion, including the foreign shorthair, ragdoll, buffering of hydrogen ions, can result in forma- Chartreux, Oriental shorthair, domestic shorttion of ammonium (NH4+). Ammonium directly hair, and Himalayan (odds ratio: >2). Breeds contributes to struvite formation and indirectly noted to have a decreased risk include the rex, facilitates nidus formation through local uroen- Abyssinian, Burmese, Russian blue, Birman, dothelial damage. and Siamese, as well as mixed-breed cats (odds Dietary moisture content has been reported ratio: <0.5).11 Cats of all ages may develop struto influence calcium oxalate urolith formation vite urolithiasis. The median age of cats with and the incidence of feline idiopathic cysti- struvite calculi was 5.75 years in one study,11 tis, for which increased moisture may reduce which was significantly younger than cats with supersaturation of crystallogenic substrates calcium oxalate calculi. Cats older than 4 years

QuickNotes Urolithiasis is the second most common cause of lower urinary tract disease in cats.

FIGURE 3 Feline struvite calculi. Note the variation in gross appearance.

Vetlearn.com | December 2009 | Compendium: Continuing Education for Veterinarians®

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SevoFlo®

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(sevoflurane) Inhalation Anesthetic For Use in Dogs Caution: Federal law restricts this drug to use by or on the order of a licensed veterinarian. DESCRIPTION: SevoFlo (sevoflurane), a volatile liquid, is a halogenated general inhalation anesthetic drug. Its chemical name is fluoromethyl 2,2,2trifluoro-l- (trifluoromethyl) ethyl ether, and its structural formula is:

Sevoflurane Physical Constants are: Molecular weight 200.05 Boiling point at 760 mm Hg 58.6°C Specific gravity at 20°C 1.520-1.525 g/mL Vapor pressure in mm Hg at 20°C 157 at 25°C 197 at 36°C 317 Distribution Partition Coefficients at 37°C: Blood/Gas 0.63-0.69 Water/Gas 0.36 Olive Oil/Gas 47-54 Brain/Gas 1.15 Mean Component/Gas Partition Coefficients at 25°C for Polymers Used Commonly in Medical Applications: Conductive rubber 14.0 Butyl rubber 7.7 Polyvinyl chloride 17.4 Polyethylene 1.3 Sevoflurane is nonflammable and nonexplosive as defined by the requirements of International Electrotechnical Commission 601-2-13. Sevoflurane is a clear, colorless, stable liquid containing no additives or chemical stabilizers. Sevoflurane is nonpungent. It is miscible with ethanol, ether, chloroform and petroleum benzene, and it is slightly soluble in water. Sevoflurane is stable when stored under normal room lighting condition according to instructions. INDICATIONS: SevoFlo is indicated for induction and maintenance of general anesthesia in dogs. DOSAGE AND ADMINISTRATION: Inspired Concentration: The delivered concentration of SevoFlo should be known. Since the depth of anesthesia may be altered easily and rapidly, only vaporizers producing predictable percentage concentrations of sevoflurane should be used. Sevoflurane should be vaporized using a precision vaporizer specifically calibrated for sevoflurane. Sevoflurane contains no stabilizer. Nothing in the drug product alters calibration or operation of these vaporizers. The administration of general anesthesia must be individualized based on the patient’s response. WHEN USING SEVOFLURANE, PATIENTS SHOULD BE CONTINUOUSLY MONITORED AND FACILITIES FOR MAINTENANCE OF PATENT AIRWAY, ARTIFICIAL VENTILATION, AND OXYGEN SUPPLEMENTATION MUST BE IMMEDIATELY AVAILABLE. Replacement of Desiccated CO2 Absorbents: When a clinician suspects that the CO2 absorbent may be desiccated, it should be replaced. An exothermic reaction occurs when sevoflurane is exposed to CO2 absorbents. This reaction is increased when the CO2 absorbent becomes desiccated (see PRECAUTIONS). Premedication: No specific premedication is either indicated or contraindicated with sevoflurane. The necessity for and choice of premedication is left to the discretion of the veterinarian. Preanesthetic doses for premedicants may be lower than the label directions for their use as a single medication.1 Induction: For mask induction using sevoflurane alone, inspired concentrations up to 7% sevoflurane with oxygen are employed to induce surgical anesthesia in the healthy dog. These concentrations can be expected to produce surgical anesthesia in 3 to 14 minutes. Due to the rapid and dose dependent changes in anesthetic depth, care should be taken to prevent overdosing. Respiration must be monitored closely in the dog and supported when necessary with supplemental oxygen and/or assisted ventilation. Maintenance: SevoFlo may be used for maintenance anesthesia following mask induction using sevoflurane or following injectable induction agents. The concentration of vapor necessary to maintain anesthesia is much less than that required to induce it. Surgical levels of anesthesia in the healthy dog may be maintained with inhaled concentrations of 3.7-4.0% sevoflurane in oxygen in the absence of premedication and 3.3-3.6% in the presence of premedication. The use of injectable induction agents without premedication has little effect on the concentrations of sevoflurane required for maintenance. Anesthetic regimens that include opioid, alpha2-agonist, benzodiazepine or phenothiazine premedication will allow the use of lower sevoflurane maintenance concentrations. CONTRAINDICATIONS: SevoFlo is contraindicated in dogs with a known sensitivity to sevoflurane or other halogenated agents. WARNINGS: Sevoflurane is a profound respiratory depressant. DUE TO THE RAPID AND DOSE DEPENDENT CHANGES IN ANESTHETIC DEPTH, RESPIRATION MUST BE MONITORED CLOSELY IN THE DOG AND SUPPORTED WHEN NECESSARY WITH SUPPLEMENTAL OXYGEN AND/OR ASSISTED VENTILATION. In cases of severe cardiopulmonary depression, discontinue drug administration, ensure the existence of a patent airway and initiate assisted or controlled ventilation with pure oxygen. Cardiovascular depression should be treated with plasma expanders, pressor agents, antiarrhythmic agents or other techniques as appropriate for the observed abnormality. Due to sevoflurane’s low solubility in blood, increasing the concentration may result in rapid changes in anesthetic depth and hemodynamic changes (dose dependent decreases in respiratory rate and blood pressure) compared to other volatile anesthetics. Excessive decreases in blood pressure or respiratory depression may be corrected by decreasing or discontinuing the inspired concentration of sevoflurane. Potassium hydroxide containing CO2 absorbents (e.g. BARALYME®) are not recommended for use with sevoflurane. ADVERSE REACTIONS: The most frequently reported adverse reactions during maintenance anesthesia were hypotension, followed by tachypnea, muscle tenseness, excitation, apnea, muscle fasciculations and emesis. Infrequent adverse reactions include paddling, retching, salivation, cyanosis, premature ventricular contractions and excessive cardiopulmonary depression. Transient elevations in liver function tests and white blood cell count may occur with sevoflurane, as with the use of other halogenated anesthetic agents.

PRECAUTIONS: Halogenated volatile anesthetics can react with desiccated carbon dioxide (CO2) absorbents to produce carbon monoxide (CO) that may result in elevated carboxyhemoglobin levels in some patients. To prevent this reaction, sevoflurane should not be passed through desiccated soda lime or barium hydroxide lime. Replacement of Desiccated CO2 Absorbents: When a clinician suspects that the CO2 absorbent may be desiccated, it should be replaced before administration of sevoflurane. The exothermic reaction that occurs with sevoflurane and CO2 absorbents is increased when the CO2 absorbent becomes desiccated, such as after an extended period of dry gas flow through the CO2 absorbent canisters. Extremely rare cases of spontaneous fire in the respiratory circuit of the anesthesia machine have been reported during sevoflurane use in conjunction with the use of a desiccated CO2 absorbent, specifically those containing potassium hydroxide (e.g. BARALYME). Potassium hydroxide containing CO2 absorbents are not recommended for use with sevoflurane. An unusually delayed rise in the inspired gas concentration (decreased delivery) of sevoflurane compared with the vaporizer setting may indicate excessive heating of the CO2 absorbent canister and chemical breakdown of sevoflurane. The color indicator of most CO2 absorbent may not change upon desiccation. Therefore, the lack of significant color change should not be taken as an assurance of adequate hydration. CO2 absorbents should be replaced routinely regardless of the state of the color indicator. The use of some anesthetic regimens that include sevoflurane may result in bradycardia that is reversible with anticholinergics. Studies using sevoflurane anesthetic regimens that included atropine or glycopyrrolate as premedicants showed these anticholinergics to be compatible with sevoflurane in dogs. During the induction and maintenance of anesthesia, increasing the concentration of sevoflurane produces dose dependent decreases in blood pressure and respiratory rate. Due to sevoflurane’s low solubility in blood, these changes may occur more rapidly than with other volatile anesthetics. Excessive decreases in blood pressure or respiratory depression may be related to depth of anesthesia and may be corrected by decreasing the inspired concentration of sevoflurane. RESPIRATION MUST BE MONITORED CLOSELY IN THE DOG AND SUPPORTED WHEN NECESSARY WITH SUPPLEMENTAL OXYGEN AND/OR ASSISTED VENTILATION. The low solubility of sevoflurane also facilitates rapid elimination by the lungs. The use of sevoflurane in humans increases both the intensity and duration of neuromuscular blockade induced by nondepolarizing muscle relaxants. The use of sevoflurane with nondepolarizing muscle relaxants has not been evaluated in dogs. Compromised or debilitated dogs: Doses may need adjustment for geriatric or debilitated dogs. Because clinical experience in administering sevoflurane to dogs with renal, hepatic and cardiovascular insufficiency is limited, its safety in these dogs has not been established. Breeding dogs: The safety of sevoflurane in dogs used for breeding purposes, during pregnancy, or in lactating bitches, has not been evaluated. Neonates: The safety of sevoflurane in young dogs (less than 12 weeks of age) has not been evaluated. HUMAN SAFETY: Not for human use. Keep out of reach of children. Operating rooms and animal recovery areas should be provided with adequate ventilation to prevent the accumulation of anesthetic vapors. There is no specific work exposure limit established for sevoflurane. However, the National Institute for Occupational Safety and Health has recommended an 8 hour time-weighted average limit of 2 ppm for halogenated anesthetic agents in general. Direct exposure to eyes may result in mild irritation. If eye exposure occurs, flush with plenty of water for 15 minutes. Seek medical attention if irritation persists. Symptoms of human overexposure (inhalation) to sevoflurane vapors include respiratory depression, hypotension, bradycardia, shivering, nausea and headache. If these symptoms occur, remove the individual from the source of exposure and seek medical attention. The material safety data sheet (MSDS) contains more detailed occupational safety information. For customer service, adverse effects reporting, and/or a copy of the MSDS, call (888) 299-7416. CLINICAL PHARMACOLOGY: Sevoflurane is an inhalational anesthetic agent for induction and maintenance of general anesthesia. The Minimum Alveolar Concentration (MAC) of sevoflurane as determined in 18 dogs is 2.36%.2 MAC is defined as that alveolar concentration at which 50% of healthy patients fail to respond to noxious stimuli. Multiples of MAC are used as a guide for surgical levels of anesthesia, which are typically 1.3 to 1.5 times the MAC value. Because of the low solubility of sevoflurane in blood (blood/gas partition coefficient at 37°C = 0.63-0.69), a minimal amount of sevoflurane is required to be dissolved in the blood before the alveolar partial pressure is in equilibrium with the arterial partial pressure. During sevoflurane induction, there is a rapid increase in alveolar concentration toward the inspired concentration. Sevoflurane produces only modest increases in cerebral blood flow and metabolic rate, and has little or no ability to potentiate seizures.3 Sevoflurane has a variable effect on heart rate, producing increases or decreases depending on experimental conditions.4,5 Sevoflurane produces dose-dependent decreases in mean arterial pressure, cardiac output and myocardial contraction.6 Among inhalation anesthetics, sevoflurane has low arrhythmogenic potential.7 Sevoflurane is chemically stable. No discernible degradation occurs in the presence of strong acids or heat. Sevoflurane reacts through direct contact with CO2 absorbents (soda lime and barium hydroxide lime) producing pentafluoroisopropenyl fluoromethyl ether (PIFE, C4H2F6O), also known as Compound A, and trace amounts of pentafluoromethoxy isopropyl fluoromethyl ether (PMFE, C5H6F6O), also known as Compound B. Compound A: The production of degradants in the anesthesia circuit results from the extraction of the acidic proton in the presence of a strong base (potassium hydroxide and/or NaOH) forming an alkene (Compound A) from sevoflurane. Compound A is produced when sevoflurane interacts with soda lime or barium hydroxide lime. Reaction with barium hydroxide lime results in a greater production of Compound A than does reaction with soda lime. Its concentration in a circle absorber system increases with increasing sevoflurane concentrations and with decreasing fresh gas flow rates. Sevoflurane degradation in soda lime has been shown to increase with temperature. Since the reaction of carbon dioxide with absorbents is exothermic, this temperature increase will be determined by the quantities of CO2 absorbed, which in turn will depend on fresh gas flow in the anesthetic circle system, metabolic status of the patient and ventilation. Although Compound A is a dose-dependent nephrotoxin in rats, the mechanism of this renal toxicity is unknown. Two spontaneously breathing dogs under sevoflurane anesthesia showed increases in concentrations of Compound A as the oxygen flow rate was

SEVO-152 January 2007

page 1 of 1

decreased at hourly intervals, from 500 mL/min (36 and 18 ppm Compound A) to 250 mL/min (43 and 31 ppm) to 50 mL/min (61 and 48 ppm).8 Fluoride ion metabolite: Sevoflurane is metabolized to hexafluoroisopropanol (HFIP) with release of inorganic fluoride and CO2. Fluoride ion concentrations are influenced by the duration of anesthesia and the concentration of sevoflurane. Once formed, HFIP is rapidly conjugated with glucuronic acid and eliminated as a urinary metabolite. No other metabolic pathways for sevoflurane have been identified. In humans, the fluoride ion half-life was prolonged in patients with renal impairment, but human clinical trials contained no reports of toxicity associated with elevated fluoride ion levels. In a study in which 4 dogs were exposed to 4% sevoflurane for 3 hours, maximum serum fluoride concentrations of 17.0-27.0 mcmole/L were observed after 3 hours of anesthesia. Serum fluoride fell quickly after anesthesia ended, and had returned to baseline by 24 hours post-anesthesia. In a safety study, eight healthy dogs were exposed to sevoflurane for 3 hours/day, 5 days/week for 2 weeks (total 30 hours exposure) at a flow rate of 500 mL/min in a semi-closed, rebreathing system with soda lime. Renal toxicity was not observed in the study evaluation of clinical signs, hematology, serum chemistry, urinalysis, or gross or microscopic pathology. DRUG INTERACTIONS: In the clinical trial, sevoflurane was used safely in dogs that received frequently used veterinary products including steroids and heartworm and flea preventative products. Intravenous Anesthetics: Sevoflurane administration is compatible with barbiturates, propofol and other commonly used intravenous anesthetics. Benzodiazepines and Opioids: Benzodiazepines and opioids would be expected to decrease the MAC of sevoflurane in the same manner as other inhalational anesthetics. Sevoflurane is compatible with benzodiazepines and opioids as commonly used in surgical practice. Phenothiazines and Alpha2-Agonists: Sevoflurane is compatible with phenothiazines and alpha2- agonists as commonly used in surgical practice. In a laboratory study, the use of the acepromazine/oxymorphone/ thiopental/sevoflurane anesthetic regimen resulted in prolonged recoveries in eight (of 8) dogs compared to recoveries from sevoflurane alone. CLINICAL EFFECTIVENESS: The effectiveness of sevoflurane was investigated in a clinical study involving 196 dogs. Thirty dogs were mask-induced with sevoflurane using anesthetic regimens that included various premedicants. During the clinical study, one hundred sixty-six dogs received sevoflurane maintenance anesthesia as part of several anesthetic regimens that used injectable induction agents and various premedicants. The duration of anesthesia and the choice of anesthetic regimens were dependent upon the procedures that were performed. Duration of anesthesia ranged from 16 to 424 minutes among the individual dogs. Sevoflurane vaporizer concentrations during the first 30 minutes of maintenance anesthesia were similar among the various anesthetic regimens. The quality of maintenance anesthesia was considered good or excellent in 169 out of 196 dogs. The table shows the average vaporizer concentrations and oxygen flow rates during the first 30 minutes for all sevoflurane maintenance anesthesia regimens: Average Vaporizer Concentrations among Anesthetic Regimens

Average Vaporizer Concentrations among Individual Dogs

3.31 - 3.63%

1.6 - 5.1%

Average Oxygen Flow Rates among Anesthetic Regimens 0.97 - 1.31 L/minute

Average Oxygen Flow Rates among Individual Dogs 0.5 - 3.0 L/minute

During the clinical trial, when a barbiturate was used for induction, the times to extubation, sternal recumbency and standing recovery were longer for dogs that received anesthetic regimens containing two preanesthetics compared to regimens containing one preanesthetic. Recovery times were shorter when anesthetic regimens used sevoflurane or propofol for induction. The quality of recovery was considered good or excellent in 184 out of 196 dogs. Anesthetic regimen drug dosages, physiological responses, and the quality of induction, maintenance and recovery were comparable between 10 sighthounds and other breeds evaluated in the study. During the clinical study there was no indication of prolonged recovery times in the sighthounds. HOW SUPPLIED: SevoFlo (sevoflurane) is packaged in amber colored bottles containing 250 mL sevoflurane, List 5458. STORAGE CONDITIONS: Store at controlled room temperature 15°-30°C (59°-86°F). REFERENCES: 1. Plumb, D.C. ed., Veterinary Drug Handbook, Second Edition, University of Iowa Press, Ames, IA: p. 424 (1995). 2. Kazama, T. and Ikeda, K., Comparison of MAC and the rate of rise of alveolar concentration of sevoflurane with halothane and isoflurane in the dog. Anesthesiology. 68: 435-437 (1988). 3. Scheller, M.S., Nakakimura, K., Fleischer, J.E. and Zornow, M.H., Cerebral effects of sevoflurane in the dog: Comparison with isoflurane and enflurane. Brit. J. Anesthesia 65: 388-392 (1990). 4. Frink, E.J., Morgan, S.E., Coetzee, A., Conzen, P.F. and Brown, B.R., Effects of sevoflurane, halothane, enflurane and isoflurane on hepatic blood flow and oxygenation in chronically instrumented greyhound dogs. Anesthesiology 76: 85-90 (1992). 5. Kazama, T. and Ikeda, K., The comparative cardiovascular effects of sevoflurane with halothane and isoflurane. J. Anesthesiology 2: 63-8 (1988). 6. Bernard, J. M., Wouters, P.F., Doursout, M.F., Florence, B., Chelly, J.E. and Merin, R.G., Effects of sevoflurane on cardiac and coronary dynamics in chronically instrumented dogs. Anesthesiology 72: 659-662 (1990). 7. Hayaski, Y., Sumikawa, K., Tashiro, C., Yamatodani, A. and Yoshiya, I., Arrhythmogenic threshold of epinephrine during sevoflurane, enflurane and isoflurane anesthesia in dogs. Anesthesiology 69: 145-147 (1988). 8. Muir, W.W. and Gadawski, J., Cardiorespiratory effects of low-flow and closed circuit inhalation anesthesia, using sevoflurane delivered with an in-circuit vaporizer and concentrations of compound A. Amer. J. Vet. Res. 59 (5): 603-608 (1998). NADA 141-103, Approved by FDA SevoFlo® is a registered trademark of Abbott Laboratories. Manufactured by Abbott Laboratories, North Chicago, IL 60064, USA Product of Japan Under license from Maruishi Pharmaceutical Co., LTD 2-3-5, Fushimi-Machi, Chuo-Ku, Osaka, Japan For customer service call (888) 299-7416. ©Abbott 8/2006 Taken from Commodity Number 03-5474/R6, SevoFlo, sevoflurane, package insert, January 11, 2007

Only SevoFlo—available through all major distributors—provides fourr unique benefits: 1. A minimum of 300 ppm water 2. Shatter-resistant PEN bottles 3. Local Abbott representatives and expert advice ce 4. Commitment to training and education

The SevoFlo Difference SevoFlo brings four added benefits to every procedure. You trust SevoFlo in the surgical suite because you know it works. But did you realize that every time you use SevoFlo you’re getting unique benefits? SevoFlo includes four key benefits that make it a smart choice for your practice: • SevoFlo contains a minimum of 300 ppm water. SevoFlo’s high water content can effectively inhibit the degradation of sevoflurane by Lewis acids. This degradation can result in by-products (such as hydrogen fluoride1) which may damage equipment, including certain types of vaporizers. • SevoFlo is packaged in shatter-resistant plastic polyethylene naphthalate (PEN) bottles. Unlike glass bottles, PEN bottles are shatter-resistant and do not contain Lewis acids. • SevoFlo has local representatives and expert advice. Count on our local Veterinary Practice Consultants for product support and advice. Also, our technical support department and panel of anesthesiologists are standing by to help and advise regarding techniques, products and equipment. • Abbott Animal Health, provider of SevoFlo, is committed to training and education. Rely on Abbott for in-clinic training and materials—such as the Anesthesia Value Program—and sponsorship of CE events to help you provide the best possible care. When choosing an anesthetic, ask yourself if you’re getting all these benefits SevoFlo delivers. To learn more about the SevoFlo difference, contact Abbott Animal Health Customer Service at 888-299-7416 or visit www.abbottanimalhealth.com. Important Information: How Supplied: SevoFlo is packaged in amber colored bottles containing 250 mL sevoflurane. Indications: SevoFlo is indicated for induction and maintenance of general anesthesia in dogs. Warnings, Precautions, and Contraindications: Like other inhalation anesthetics, sevoflurane is a profound respiratory depressant. Respiration must be monitored closely in the dog and supported when necessary with supplemental oxygen and/or assisted ventilation. Due to sevoflurane’s low solubility in blood, increasing concentration may result in rapid hemodynamic changes compared to other volatile anesthetics. SevoFlo is contraindicated in dogs with a known sensitivity to sevoflurane or other halogenated agents. Adverse Reactions: The most frequently reported adverse reactions during maintenance anesthesia were hypotension, followed by tachypnea, muscle tenseness, excitation, apnea, muscle fasciculations and emesis. See package insert for full prescribing information. Note: The FDA has determined that generic animal drugs that are classified as bioequivalent can be substituted with the full expectation that the substituted product will produce the same clinical effect and safety profile as the reference product.

1. Anesthesia Analgesia 2007;104;1447-51

See Page 544 for Product Information Summary

FREE CE Feline Struvite Urolithiasis

FIGURE 4

Algorithm for management of struvite urolithiasis in cats. FIC = feline interstitial cystitis, UTI = urinary tract infection

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FREE

Feline Struvite Urolithiasis CE are 2.5 times more likely to develop struvite calculi compared with cats younger than 4 years. The highest incidence was seen in cats between 4 and 7 years of age, with a 10-fold greater risk compared with cats between 1 and 2 years of age. Infection-induced calculi were most common in cats younger than 1 year or older than 10 years.11

Incidence Worldwide, urolithiasis has been reported in 15% to 23% of all cats with diseases of the lower urinary tract, and 22% to 50% of those uroliths are composed of struvite.2,9,12,13 Over the past 20 years, the ratio of calcium oxalate stones to struvite stones increased signiﬁcantly, but it has recently reached a plateau. Struvite and calcium oxalate stones currently occur in almost equal proportions.14 Percentages of struvite submissions may not accurately reﬂect the true incidence of struvite calculi because of effective dissolution therapy without quantitative analysis. While most cases of lower urinary tract disease in cats are idiopathic cystitis, the management of this condition is different from urolithiasis.2,12

Diagnosis Hematuria, pollakiuria, stranguria, and dysuria are common clinical signs of lower urinary tract disease and are not speciﬁc for cystic calculi. Most cats aged 1 to 10 years with lower urinary tract disease have idiopathic cystitis (55% to 64%). Urolithiasis accounts for 15% to 23% of cases of feline lower urinary tract disease; up to 11% of cases are due to anatomic defects; and 1% to 8% are urinary tract infections.12,13,15,16 In cats older than 10 years, 46% of lower urinary tract disease cases are related to infection and 17% to concurrent infection and calculi.17 Alkaline urine increases the SAP and is commonly found in association with struvite urolithiasis. Crystalluria (FIGURE 1) without stone formation is not pathologic and can be found in healthy animals. In vitro crystal formation can occur as a result of prolonged storage, refrigeration, and alkalinization.18,19 Crystalluria can be conﬁrmed by evaluation of fresh urine samples. Pyuria may result from concurrent infection. Urine culture via cystocentesis is recommended to evaluate for bacterial infection.

BOX 1

Clinical Pearls: Dissolution Therapy Patient selection Female cats with uroliths ≤5 mm Struvite crystalluria Radiographic evidence of radiopaque stones No known dietary contraindications Therapy Select calculolytic diet Evaluate and treat for concurrent urease-producing infections throughout duration of therapy Methods of evaluating owner compliance with diet Reduction in blood urea nitrogen Urine speciﬁc gravity <1.030 Elimination of struvite crystalluria Complete diet history Monitor urine pH Recommended follow-up Serial radiography at monthly intervals Repeat urine culture if urease-producing organisms were initially suspected Repeat urinalysis and serum biochemistry if owner noncompliance is suspected Treatment failure Owner or patient noncompliance Failure to reduce size or number of uroliths on sequential radiographs

Radiography is a sensitive test for detection of struvite calculi, which are radiopaque (FIGURE 2). If the calculi are small (<3 mm), ultrasonography or double-contrast cystography is superior to radiography for detection.2 Struvite uroliths tend to have smooth contours, but they vary in gross appearance (FIGURE 3). A history of struvite urolithiasis, struvite crystalluria, alkaline urine, and compatible radiographic features increases the suspicion for struvite urolithiasis, but deﬁnitive diagnosis is based on quantitative stone analysis. An algorithm for management of struvite urolithiasis is presented in FIGURE 4.

QuickNotes Struvite calculi are common in the feline lower urinary tract, and their prevalence may be rising.

Treatment Therapy can be divided into stone dissolution and stone removal. Dissolution therapy has the beneﬁts of avoiding major surgery, perioperative complications, and general anesthesia. Its disadvantages include treatment failure, reliance on owner and patient compliance, and

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A perfect ﬁt...

no matter what BOEHRINGER INGELHEIM VETMEDICA, INC. (BIVI), has invested in the long-term growth of its animal health business by acquiring select Fort Dodge Animal Health products. That means our product portfolio in the pet, equine and cattle markets has grown. And that BIVI’s already substantial investment in developing innovative animal health products has increased signiﬁcantly. What hasn’t changed is our commitment to understanding our customers’ needs. While we are making some changes here at BIVI, we assure you we are taking the necessary steps to make sure your business is not interrupted.

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coat you wear. For questions or concerns, please contact your local BIVI representative or visit WWW.BI-VETMEDICA.COM. For customer service or to ďŹ nd your local BIVI representative, call 1-800-325-9167. For technical product information, contact

1-866-638-2226.

FREE CE Feline Struvite Urolithiasis

FIGURE 5 Radiographs of a cat with presumptive struvite cystic calculi.

Before dissolution therapy.

costs associated with monitoring efﬁcacy. BOX 1 lists patient selection criteria and other con-

QuickNotes Struvite uroliths in cats are uncommonly caused by ureaseproducing bacteria.

550

One month after dissolution therapy.

vals is used to quantify changes in stone size and number (FIGURE 5). These diets should be continued for 2 to 4 weeks beyond radiographic resolution to ensure complete dissolution of calculi <3 mm, which are not radiographically visible. If a calculolytic diet is contraindicated (e.g., pregnancy, immaturity) or obstruction is present, physical removal of stones via surgical or nonsurgical techniques is recommended. Additionally, if infection is present, dissolution therapy is ineffective without antibiotic therapy. It is recommended that antibiotics be continued 1 month beyond radiographic dissolution, as bacteria can be released from calculi during therapy or can persistently colonize the uroendothelium and result in relapse.20,21 Infectioninduced struvite uroliths generally take longer to dissolve than sterile struvite uroliths.21 In cats, nephroliths and ureteroliths are rarely composed of struvite and mostly composed of calcium oxalate. However, unlike feline struvite cystoliths, which are predominantly sterile, most feline struvite nephroliths (80%) are associated with urine culture results positive for urease-producing organisms.23,24

siderations for dissolution therapy. The potential for urethral obstruction as calculi become smaller exists; however, no literature supports dissolution as a risk factor for obstruction at this time. Dissolution therapy is effective in management of sterile feline struvite calculi. The key goals of dissolution diets include reduction in urine pH to ≤6.3 and reduction of dietary magnesium.20 One study21 found a mean dissolution time of 36 days (range: 14 to 141 days) for sterile uroliths and 44 days (range: 12 to 92 days) for infected uroliths when Hill’s Prescription Diet s/d (Hill’s Pet Nutrition) was used. Another commercially available dissolution diet (Medi-Cal Dissolution Formula, Veterinary Medical Diets, Guelph, Ontario) was effective in 79% of cases with clinical suspicion for sterile struvite.21 Treatment failure has been noted with mixed-composition calculi, owner noncompliance, and food refusal.22 Dissolution diets are not recommended for growing cats or for cats that are acidemic, pregnant, or hypervolemic because these diets are protein restricted and acidifying and can result in volume expan- Monitoring sion from increased sodium concentration.20 After deﬁnitive therapy, routine monitoring Additionally, male cats may not be ideal can- with urinalysis and abdominal radiography is didates for dissolution therapy because of the recommended. Early detection of recurrence chance of urethral obstruction. may allow nonsurgical therapies to be used. The selected diet should be fed exclusively. Cats with risk factors for urinary tract infecRadiographic evaluation at 3- to 4-week inter- tions (i.e., chronic kidney disease, polyuria,

Compendium: Continuing Education for Veterinarians® | December 2009 | Vetlearn.com

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FREE CE Feline Struvite Urolithiasis

BOX 2

Recommendations for Prevention of Feline Struvite Urolithiasis Encourage water consumption Feed canned food Provide flavored water, running water bowls, or constant fresh water, according to cat’s preference Goal: obtain a urine specific gravity <1.030 Institute dietary management Avoid excess magnesium, phosphorus, calcium, and chloride Indications: urinary pH is consistently >6.5 Goal: maintain a pH <6.5 Conduct diagnostic monitoring Urinalysis: evaluate urine specific gravity, crystalluria, and urine pH (to assess dietary efficacy) Urine culture: evaluate for concurrent infection Abdominal radiography: evaluate for early recurrence

diabetes mellitus, hyperthyroidism, perineal urethrostomy) should have urine samples cultured every 3 to 6 months.25–27 Monitoring urine pH is recommended to assess dietary compliance and efficacy. Values between 6.0 and 6.5 may reduce the incidence of calcium oxalate and struvite crystal formation. Monitoring urine specific gravity has been recommended to assess water consumption. A urine specific gravity <1.030 has been recommended as a goal.1,28

Prevention A general recommendation for prevention of urolithiasis is to increase water consumption to encourage diuresis and reduce time for aggregation and crystallization (BOX 2). This may be most effectively completed with a transition to a moist diet; however, providing flavored or running water may encourage increased water intake.1 Dietary therapy may reduce calculi recurrence, although clinical studies on recurrence rates are lacking. Epidemiologic studies suggest that a urine pH of approximately 6.0 to 6.3 and consumption of a low-magnesium diet reduce recurrence of naturally occurring sterile struvite urocystoliths.21,29 However, acidification of the urine to <6.29 may increase the risk of calcium oxalate urolith formation.30 Dietary analysis and quantification of “alkalogenic” and “acidifying” components may aid in predicting urine pH but cannot be recommended at this time.30 Urinary acidifiers (DL-methionine, ammonium chloride) should be considered only when the urine pH is >6.5 with ad libitum feeding conditions.1 Urinary acidifiers alter the urine pH and SAP but cannot reduce the organic fraction responsible for the matrix formation.7 Commercial diets designed to prevent struvite recurrence have not been critically evaluated in randomized, controlled studies. These diets may or may not influence the recurrence rates in clinical patients.

Conclusion Struvite cystic calculi are common; dietary therapy is the mainstay of prevention. Diets with reduced magnesium that maintain a urine pH between 6 and 6.3 are recommended despite lack of evidence of efﬁcacy. Struvite uroliths can be ved. effectively medically dissolved or physically removed. CE TEST 1 This article qualiﬁes for 3 contact hours of

3 CE CREDITS

continuing education credit from the Auburn University College of Veterinary Medicine. Subscribers must take individual CE tests online and get real-time scores at Vetlearn.com. Those who wish to apply this credit to fulﬁll state relicensure requirements should consult their respective state authorities regarding the applicability of this program.

ON THE WEB 552

The references for this article are available at

Vetlearn.com.

Compendium | December 2009 | Vetlearn.com

Heartw He worrm

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It’s NOT Re evolution®! New look . Same effective product.

Heartwo orm m prevention and much more. BayerDVM.com Ba

Advantage Multi® for Dogs (imidacloprid + moxidectin) Topical Solution CAUTION: Federal (U.S.A.) law restricts this drug to use by or on the order of a licensed veterinarian. WARNINGS: For the ﬁrst 30 minutes after application: Ensure that dogs cannot lick the product from application sites on themselves or other treated dogs, and separate treated dogs from one another and from other pets to reduce the risk of accidental ingestion. Ingestion of this product by dogs may cause serious adverse reactions including depression, salivation, dilated pupils, incoordination, panting and generalized muscle tremors. In avermectin sensitive dogs, the signs may be more severe and may include coma and death. CONTRAINDICATIONS: Do not administer the product orally. Do not use this product (containing 2.5% moxidectin) on cats. HUMAN WARNINGS: Children should not come in contact with the application site for two (2) hours after application. See Page 552 for Product Information Summary

© 2009 Bayer HealthCare LLC, Animal Health Division, Shawnee Mission, Kansas 66201 Bayer, the Bayer Cross and Advantage Multi are registered trademarks of Bayer. Revolution is a registered trademark of Pﬁzer Inc.

AM09885

Update on Feline Upper Respiratory Diseases: Introduction and Diagnostics

Abstract: Clinical signs of upper respiratory disease are com-

❯❯ Jessica Quimby, DVM, DACVIMa ❯❯ Michael R. Lappin, DVM, PhD, DACVIM Colorado State University

Relatively common causes of sneezing or nasal discharge in cats that primarily involve the nasal cavity or nasopharynx include infections, chronic rhinosinusitis, foreign bodies, tooth root disease, neoplasia, inflammatory polyps, nasopharyngeal stenosis, trauma, and cleft palate1–3 (TABLE 1). In addition, vomiting or regurgitation can lead to sneezing or nasal discharge if gastrointestinal contents are aspirated into the nose via the nasopharynx. Serous nasal discharge is characteristic of most acute diseases of the nasal cavity and may precede mucopurulent nasal discharge. Chronic serous nasal discharge is most commonly associated with viral and allergic etiologies. Mucopurulent nasal discharge (FIGURE 1) is a sign of inflammation and occurs in association with fungal disease, primary bacterial disease, or overgrowth of normal bacterial flora secondary to chronic nasal disease (neoplasia, chronic rhinosinusitis, oronasal fistula, foreign body, inflammatory polyp, or viral disease). Epistaxis alone is most common with trauma, acute foreign body, hypertension, or coagulopathy. Epistaxis that develops in conjunction with, or after, mucopurulent dis-

mon in cats. Common diagnostic differentials include viral, bacterial, and fungal infections; chronic rhinosinusitis; foreign bodies; tooth root disease; neoplasia; inﬂammatory polyps; nasopharyngeal stenosis; and trauma. A complete diagnostic workup is important to determine the etiology so that the treatment regimen can be appropriately directed and maximal response to therapy obtained.

linical signs of upper respiratory disease, including sneezing and nasal discharge, are common in cats. Some diseases are commonly associated with sneezing, and others are more commonly associated with sonorous breathing with or without gagging; coughing can sometimes be present, as well as epiphora, halitosis, and dysphagia.1–3 Sneezing is a superﬁcial reﬂex that originates in the mucous membranes lining the nasal cavity and is easily induced by chemical or mechanical stimuli. During a sneeze, air is forcefully expulsed through the respiratory passageways at a great velocity to clear them. Nasal discharge can be serous, mucopurulent, or hemorrhagic.

Etiologies and Clinical Signs

At a Glance Etiologies and Clinical Signs Page 554

General Diagnostic Considerations Page 557

MORE ON THE WEB a Dr. Quimby discloses that she has received study funding from Bayer HealthCare Animal Health.

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Coming Soon: A companion article on diseasespecific tests and therapies will be published in January 2010.

IT’S TIME FOR A NEW CHOICE Introducing new ProZinc™ (protamine zinc recombinant human insulin), the ﬁrst FDA-approved long-acting insulin speciﬁcally for cats Proven to deliver consistent round-the-clock glycemic control, new PROZINC helps you reduce clinical signs and provide long-term management for feline diabetes patients, especially newly diagnosed or poorly regulated diabetic cats.1 PROZINC insulin, like other insulin products, is not free from adverse reactions. The most common adverse reaction observed is hypoglycemia. Try new PROZINC for your feline diabetes patients, and see for yourself the difference a long-acting insulin offers for consistent glycemic control. www.ProZinc.us www.BI-Vetmedica.com 1

See Page 556 for Product Information Summary

See product indicator for more details.

In association with

AMERICAN ASSOCIATION OF

FELINE PRACTITIONERS

About AAFP The American Association of Feline Practitioners improves the health and well-being of cats by supporting high standards of practice, continuing education, and scientiﬁc investigation. Feline practitioners are veterinary professionals who belong to this association because they are “passionate about the care of cats”!

FIGURE 1

American Association of Feline Practitioners 203 Towne Centre Drive Hillsborough, NJ 08844-4693 phone: 800-874-0498 phone: 908-359-9351 fax: 908-292-1188

Clinical appearance of chronic mucopurulent nasal discharge.

e-mail: info@catvets.com

charge is most common with fungal disease, neoplasia, oronasal fistula, and, occasionally, chronic foreign bodies. Vasculitis is a rare cause of nasal discharge in cats; it is a more common cause in dogs with diseases such as ehrlichiosis and bartonellosis. Unilateral nasal discharge is more likely with foreign bodies, oronasal fistula, and neoplasia, although discharge can become bilateral as neoplasia progresses. Bilateral discharge is a nonspecific sign that can have almost any etiology.1 Infectious agents are commonly associated with sneezing or nasal discharge in cats. The primary viral agents are feline herpesvirus 1 (FHV-1; FIGURE 2) and feline calicivirus (FCV).4–8 Bacterial agents that have been described as primary respiratory patho-

gens in cats include Bordetella bronchiseptica, Chlamydophila felis, Streptococcus canis, and Mycoplasma spp; Corynebacterium spp, Escherichia coli, Pasteurella multocida, Pseudomonas aeruginosa, Streptococcus viridans, and Staphylococcus intermedius are also commonly detected but are generally thought to be secondary invaders.7–16 Cryptococcus neoformans and Aspergillus spp are the most common fungal causes of upper respiratory disease in cats.17,18

Media contact: Valerie Creighton, DVM, DABVP

General Diagnostic Considerations Signalment and lifestyle often help reﬁne the differential diagnosis and direct a diagnostic workup. Brachycephalic breeds may be predisposed to nasal disorders due to physical

TABLE 1

Clinical Manifestations of Upper Respiratory Diseases in Cats Disease

Signalment and History

Sneezing

Nasal Discharge

Respiratory Noise

Acute viral infection

Young to any age; acute

Often

Serous to mucopurulent

Sometimes

Bacterial infection

Any age; chronic

Sometimes

Mucopurulent

Sometimes

Fungal infection

Any age; chronic

Sometimes

Mucopurulent to hemorrhagic

Sometimes

Nasopharyngeal polyp

Young; chronic

Sometimes

Mucopurulent

Often

Chronic rhinosinusitis

Any age; chronic

Often

Mucopurulent to hemorrhagic

Sometimes

Older; chronic

Sometimes

Mucopurulent to hemorrhagic

Often

Any age; chronic

Rarely

Uncommon

Often

Any age; acute

Often

Variable

Rarely

Neoplasia Nasopharyngeal stenosis Foreign body

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conformation.19 Neoplasia is more likely in older cats,1 and nasopharyngeal polyps are more common in younger cats.20 Outdoor cats are more likely to acquire foreign bodies, sustain trauma, or develop infectious etiologies.1 Cats in crowded housing conditions such as catteries, shelters, or multicat households are more likely to develop acute or chronic viral or bacterial rhinitis.6 Obtaining a complete history is important for determining the duration of the clinical signs. Acute onset of clinical signs is common with viral agents, foreign bodies, and trauma. The diagnostic workup of sneezing and nasal discharge is commonly completed in three phases.

Phase 1

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Most cats with acute disease are evaluated with noninvasive tests and therapeutic trials. A complete physical examination with careful attention to the head and neck, including ocular retropulsion, should be performed.An otic examination should be completed to evaluate the tympanum for bulging or discoloration; these changes commonly occur with nasopharyngeal polyps. Deformation of the nose or face, exophthalmia, or pain on palpation of the nasal or facial bones is most consistent with fungal disease or neoplasia.1 An oral examination should be performed to assess for dental disease that could be causing an oronasal fistula, gingivostomatitis that could be consistent with FHV-1 or FCV infection, and defects in the hard or soft palate. External ocular examination may reveal conjunctivitis, which can be a sign of infection with FHV1, FCV, Mycoplasma spp, or C. felis. A fundic examination is performed to evaluate for lesions consistent with lymphoma or C. neoformans infection. A cold microscope slide placed in front of the nose can aid in assessing airflow and determining whether obstruction is unilateral or bilateral, although these findings should not limit diagnostic investigation to one side of the nose. Although identification of fungal organisms is uncommon, cytology should be performed on samples of mucoid to mucopurulent nasal discharge to evaluate for the presence of C. neoformans or hyphae consistent with Asper-gillus or Penicillium spp. Neutrophils and bacteria are commonly detected if mucopurulent disease is present, but their presence does not prove primary bacterial disease. Likewise, hyphae do not confirm primary fungal disease because they may represent contamination or infection secondary to another underlying cause. Secondary infections result in the same types of discharge as primary infections. If lymph nodes draining the head are enlarged, they should be aspirated to evaluate for the presence of lymphoma, metastatic neoplasia, and fungal agents.

558

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FIGURE 2

Clinical appearance of a kitten with herpesvirus infection.

QuickNotes Signs of nasal disease are nonspeciﬁc, and a diagnostic workup is necessary to pinpoint the etiology and direct therapy.

560

Bacterial culture and antimicrobial susceptibility testing of nasal discharge samples are generally not recommended because the results typically yield normal intranasal bacterial ﬂora and are, therefore, difﬁcult to interpret.21 However, in respiratory outbreaks in catteries, pet stores, shelters, or multiple cat households, culture may be indicated to determine whether pathogenic B. bronchiseptica is present. Molecular diagnostic assays are available for many respiratory agents, including FHV-1, FCV, C. felis, Mycoplasma spp, and B. bronchiseptica. However, cats can be asymptomatic carriers of these agents, and the FHV-1, FCV, and C. felis assays also amplify vaccine strains; therefore, positive results do not prove a disease association, especially for FHV-1 and FCV, which may have relatively high prevalences in the healthy cat population.4,5,22 A recent study23 failed to link infection with Bartonella spp to rhinitis in cats, so the question of whether to perform serology, culture, or polymerase chain reaction (PCR) assays for Bartonella spp in cats with rhinitis is controversial. If a clinician chooses to test for evidence of Bartonella infection, samples should be evaluated by PCR or culture in addition to serology, as serology alone has been shown to produce false-negative results in up to 15% of

infected cats. In addition, only approximately 40% of seropositive cats are currently infected; therefore, a positive serologic test result does not prove bartonellosis.24 A complete blood cell count (CBC), a serum biochemical panel, and urinalysis are recommended to rule out other systemic disease processes in cats with chronic disease. In general, CBC results are of low yield but may reveal eosinophilia in some cats with fungal or allergic disease, thrombocytopenia in some cats with epistaxis, or other cytopenias that might accompany FeLV or FIV infection. FeLV and FIV do not cause sneezing and nasal discharge primarily, but they have been associated with lymphoma and may induce immunodeﬁciency that predisposes to other infections; therefore, testing for these agents is indicated. A Cryptococcus antigen test is also recommended as a preliminary test for cats with chronic nasal discharge, particularly those with nasal deformation, lymphadenopathy, or retinal lesions.25 Although thoracic radiographs are generally normal, they are indicated to rule out pulmonary involvement of fungal disease and metastatic neoplasia. In cats with epistaxis, a blood pressure reading, coagulation proﬁle, and buccal mucosal bleeding test are recommended, and thromboelastography may also be useful. Therapeutic trials are commonly attempted in cats with mild disease and usually consist of antibiotics, antiviral drugs, immunomodulators, or antihistamines.

Phase 2 If the physical examination indicates the need for further diagnostic workup, a deﬁnitive diagnosis is not made during Phase 1, or if routine therapeutic trials fail, more aggressive diagnostic testing (requiring general anesthesia) should be pursued. Phase 2 diagnostics usually consist of pharyngeal examination, computed tomography (CT) or skull and dental radiography, rhinoscopy, bacterial and fungal cultures, and biopsy for histology. In anticipation of the potential for biopsy, a platelet estimate and an activated clotting time or other coagulation function test should be conducted before anesthesia is induced.

Compendium: Continuing Education for Veterinarians® | December 2009 | Vetlearn.com

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FIGURE 3 Computed tomography (CT) images of two cats presented for upper respiratory signs.

CT appearance of mild chronic rhinitis.

QuickNotes Although computed tomography is more expensive, it has many advantages over skull radiography.

General anesthesia is induced by administering approximately one-third of an induction dose of propofol, a short-acting thiobarbiturate, or ketamine combined with diazepam. The arytenoid cartilages are examined to make sure both are abducting normally on inspiration. Oropharyngeal examination is performed to evaluate thoroughly for masses, FIGURE 4

Rhinoscopic image from a cat with chronic rhinitis. The mucosa is irregular, erythematous, and swollen, and there is loss of turbinate structure.

562

CT appearance of a nasal tumor. A mass effect is noted in the nasal cavity. The white arrow indicates bony lysis and loss of the nasal septum; the red arrow indicates complete obstruction of the nasopharyngeal canal by the mass.

foreign bodies, or palate defects. A spay hook and dental mirror can be used to help manipulate the soft palate to allow visualization of the nasopharynx to check for polyps, other masses, foreign material, or nasopharyngeal stenosis. A thorough dental examination should be performed and all teeth probed for evidence of an oronasal ďŹ stula. If a deďŹ nitive diagnosis is not made, CT or nasal, sinus, and dental radiography is conducted. Radiography must be performed with the patient under anesthesia for accurate positioning and include lateral, ventrodorsal, intraoral, and open-mouth bullae views. Nasal imaging can reveal increased density in the nasal cavity or bony lysis that could be consistent with a mass, turbinate destruction consistent with chronic rhinosinusitis or fungal disease, radiopaque foreign objects, or tooth-root abscessation.26,27 Although more expensive, CT has the advantages of allowing better visualization of the sinuses and tympanic bullae, better assessment of bony lysis, and assessment of the cribriform plate and brain to evaluate the extent of a lesion.28 It is also quicker to conduct than

Compendium: Continuing Education for VeterinariansÂŽ | December 2009 | Vetlearn.com

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QuickNotes The gross appearance of the nasal mucosa on rhinoscopy does not always correlate with the histopathologic diagnosis, so biopsy samples should always be obtained.

564

a full series of skull radiographs and allows biopsy samples can be submitted for bacterial for radiotherapy treatment planning, if indi- and fungal cultures.30 cated. CT is the preferred imaging modality, especially if a mass is suspected (FIGURE 3). Phase 3 Images should be obtained before rhinos- Exploratory rhinotomy allows direct visualcopy and biopsy are performed to avoid ization of the nasal cavity to identify foreign hemorrhage obscuring details in the nasal objects, masses, or fungal plaques and is occasionally conducted in dogs to aid in the diagpassages. Depending on the radiography or CT find- nostic workup and in the treatment of some ings, the nasopharynx is examined with a flex- diseases. However, it is rarely conducted in cats, ible rhinoscope, and rigid rhinoscopy of the except for cases requiring removal of chronianterior nasal cavity is conducted. Rhinoscopy cally embedded foreign bodies or cases of allows direct visualization of the nasal cav- Aspergillus or other sinus infections that were ity, detection and removal of foreign objects, refractory to treatment or for which endoscopic detection and debridement of fungal plaques, debridement was insufficient. Nasal cryptococand assessment for inflammation, turbinate cosis rarely requires debulking in cats. In gendestruction, and masses (FIGURE 4). However, eral, there is no added benefit of debulking if a mass is present, rhinoscopy does not allow nasal tumors before chemotherapy (for lymassessment of the extent of bony lysis, mak- phoma) or radiation therapy. While removing ing additional imaging important. In addition, turbinate tissue can increase airflow through the gross appearance of the nasal mucosa on the nasal cavities, bacterial osteomyelitis and rhinoscopy does not always correlate with the some nasal discharge often persist, so this prohistopathologic diagnosis, so biopsy samples cedure is generally not recommended for cats should always be obtained.29 with chronic inflammatory rhinitis. If no foreign material is visualized on rhinoscopy, the nasal cavity is flushed with Conclusion sterile saline to evaluate for the presence Clinical signs of upper respiratory disease are of hidden material. The cuff of the endotra- common in cats. Viral upper respiratory infeccheal tube should be checked for full infla- tions, trauma, and foreign bodies are perhaps tion before nasal lavage is performed with the most common diagnostic differentials saline administered under pressure. In cats, when the onset of clinical signs is acute, but we recommend lavaging from the anterior when the signs are more chronic, bacterial nares caudally. Gauze should be placed in the and fungal infections, chronic rhinosinusitis, oropharyngeal area, and a 20-, 35-, or 60-mL chronically embedded foreign bodies, tooth syringe can be used to forcefully flush saline root disease, neoplasia, inflammatory polyps, through the nose while the nares are pinched and nasopharyngeal stenosis must be considoff to create pressure. Material flushed from ered. A diagnostic workup can be performed in the nose (or oropharynx) should be caught on several stages. A minimum database, cytology, the gauze and examined for foreign bodies. If infectious disease assays, diagnostic imaging, no foreign material is found, biopsy samples and biopsy may be required to determine the are taken using a bone curette or the largest etiology so that the treatment regimen can be biopsy instrument that can be passed through appropriately directed and maximal response the nares. Most rigid endoscopes are too large to therapy obtained. for use with the biopsy sleeve in many cats; however, a gastroscopic biopsy instrument ON THE can often be passed next to the camera of a The references for this WEB small rigid scope to perform a directed biopsy. article are available on Alternatively, the biopsy site can be chosen Vetlearn.com. based on the results of diagnostic imaging or rhinoscopy. If indicated, flushed material or

Compendium: Continuing Education for Veterinarians® | December 2009 | Vetlearn.com

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December 2009 Vol 31(12)

the home page for veterinary professionals CE ARTICLES HANDOUT ❯❯ What You Need to Know About Feline Upper Airway Infections

ns ons your cat Airway Infectio r what vaccinati have been can remembe like the your cat might your cat. And, just has had, when cat, and when an infected an infected Some litterbox as can play a role exposed to of being sick. your hands show signs help common cold, so if you have cat began to necessar y to g these viruses, tests may be hands before in spreadin laborator y cat, wash your ss. or touch a sick h the diagnosi with cat! touching another are no longer sick, many ite they herafter Even with feline lose their appet been infected s Many sick cats cats that have transmit these stion affect calicivirus can conge seek profesnasal e, pesvirus and because cats. Therefor a these cats introducing viruses to other of smell, so y advice before history the sense their sional veterinar with baby n vaccination an unknow e tempted with your cat in new cat with ne to be may need treat or before placing us treat. err delicious into your house her anot anoth or setting ar food an unfamili facility. trol a boarding

Feline Upper

an Can How Ca

CLIENT HANDOU T

UT CLIENT HANDO CLIEN

Cats, especially kittens, often get upper airway infections. This handout provides information about feline upper airway infections and offers suggestions and solutions to cat owners for preventing and treating these infections. The handout can be found on pages 579–580 or can be downloaded from Vetlearn.com.

My e Keep IK

kep Cats that are uppe contracting allowed outside boarding facilit household are diseases. Kit immune sys Vaccine reduce the

y? Cat Health

What Yo u Should Know

Feline Up per

Sneezin g? Coughin g? Your

About

Airway In fections Need Mor e Than Chic

Kitty May

Cats, espec ially kitten airway (respiratory s, often get upper cat show ) s any signs infections. If your such as of respir sneezing, infecte eyes, or wheezing, atory illness, a runny “gummy” tion g nose make an appointmen (see box below shou her evalu ated right t to have him ), or away. Depe nes Do If My Caton their cause ation nding Guideli , upper Vaccin Wh Do I What can quick airway Sick? ly becom infections Is Already in kitten s. In adult e serious, espec D tions can ially cats, untre lead ated to other w infections (secondary infecor dama resulting ) ge delica in chron te sinus ic probl es, Most feline ems. upper are cause If your cat d by virus airway infect an appoin shows any devel ions Flag signs es, tment Red op but some of respira to have secondary Raising The tory him or cats Signs of bacterial her evalua illness, make upper What ted right respiratory infections. also be Causes away. linked Airway disease Feline to other like allerg can Infectio Upper serious Approximat ies, denta ns? problems, the prese l disea se, cance nce of infections ely 90% of all a foreig nose or r, or upper n objec the back airway common in cats are cause t in the of the viruses: d mouth. and feline feline herpeby two calici virus. Feline svirus-1 rus is relate What Are herpesvithe Sign cold sores d to the virus that cause s? however, and chickenpo x in peop s people Signs of the feline canno le; upper airwa virus. Uppe t get sick from in cats vary tions in y r airwa cats can is causin depending infection y infecon what fungi or g them. also be cause bacteria. The most to be co-in It is comm d by common signs are: Sneezing than one fected—infected on for cats agent (e.g., with more terium) Watery or muco at the same a virus and discharge us a bacmake treatm time— which the eyes from ent and can and more or nose difﬁcult. recovery longe Cough r

infection effective help lim

Fever Lethargy Loss of appet Less comm ite or weight on signs include: Hoarse “voice” Change in facial shape Ulcers in the mouth or eyes

ken Sou p!

How Are Spread? These Dise

ases Feline upper airwa spread the same y infections are way as cold: a the comm healthy cat come with an on s in conta object that has ct an infect been used ed food bowl cat—for exam by ple, a share or toy. shared items can Frequently disinf d sion risk. help reduc ecting Feline 12/09 Produc calicivirus e transmisspread ed in when a version can also of this clientassociation with healthy be Vetstre cat uses handout is also availab et. A custom the same izable, le at Compe downloadable ndiumV et.com .

E-ALERT ❯❯ COMPENDIUM E-JOURNAL, a monthly e-alert, gives you immediate access to this month’s journal. Sign up at Vetlearn.com.

566

Compendium

❯❯ Perfusion Versus Hydration: Impact on the Fluid Therapy Plan ❯❯ Caroline C. Tonozzi, Elke Rudloff, and Rebecca Kirby Creating a fluid therapy plan adequate to meet an individual patient’s needs depends on identifying whether the animal has poor perfusion, is dehydrated, or both. This article reviews the body’s fluid compartments, fluid dynamics, and the clinical parameters used to differentiate perfusion from hydration and create a fluid therapy plan.

VIDEOS ❯❯ Ear Anatomy Videos The November Applied Dermatology article, “Otitis: Anatomy Every Practitioner Should Know,” by Dr. Craig E. Griffin, addresses ear cleaning and identifying different structures of the canine and feline ear. Dr. Griffin has submitted five videos to correspond with his article. Topics include otoscopy of the ear canal, movement of the tympanic membrane in response to water pressure, and a demonstration of the massage point at the base of the ear (which can be used with an ear cleaning handout available online).

❯❯ Avian Transfusion Medicine ❯❯ Shannon Shaw, Tom Tully, and Javier Nevarez Anemia is deﬁned as a decreased capacity of the blood to carry oxygen and is recognized by packed cell volume, erythrocyte, and hemoglobin values below reference ranges. Causes of anemia in birds include blood loss, heavy metal toxicosis, parasitic infection, and chronic disease. Several differences exist between avian and mammalian physiology, including the avian ability to tolerate greater losses of blood. However, the use of blood products has become an effective tool for treating anemic avian patients. Whole blood transfusions (autologous, homologous, and heterologous) and administration of hemoglobinbased, oxygen-carrying solutions are the treatments used most commonly in birds. NEWS BITE

Did You Know? Internet Popularity Among Pet Owners a Big Plus The Internet is, by Packaged Facts’ estimates, the fastest growing sales venue for pet products in the United States, with sales expected to surpass $1 billion by 2012, based on more marketers and retailers using the medium as well as the above-average likelihood of pet owners to shop via the Internet and rely on it for information. This is especially good news for “info-centric” health products, which are already heavily represented on the Internet, reﬂecting the grass-roots origins of many such products as well as the ability of the Internet to communicate product beneﬁts with detailed information. The Internet is also important because it hosts a virtual community of pet devotees who exchange pet product ideas and product tips through Web sites, chat groups, blogs, and e-mail.

Compendium has gone GREEN!

To receive the digital version, register today at Vetlearn.com — It’s FREE! Compendium has gone digital! This is the final printed edition. To receive 24/7 access to complete digital issues, simply go to www.vetlearn.com/pin, enter your unique 8-character pin (located at the top right of your address label), and get instant access to today’s top veterinary information — FREE!

3 CE CREDITS

CE Article 2

In collaboration with the American College of Veterinary Surgeons

Vacuum-Assisted Wound Closure: Application and Mechanism of Action ❯❯ Kristin A. Kirkby, DVM, MS, CCRT, DACVS ❯❯ Jason L. Wheeler, DVM, MS, DACVS ❯❯ James P. Farese, DVM, DACVS ❯❯ Gary W. Ellison, DVM, MS, DACVS

❯❯ Nicholas J. Bacon, MA, VetMB, DECVS, MRCVS, DACVS ❯❯ Colin W. Sereda, DVM, MS, DACVS ❯❯ Daniel D. Lewis, DVM, DACVSa University of Florida

Abstract: Vacuum-assisted closure (VAC) is a wound management therapy that creates local negative pressure over a wound bed to promote healing. Beneﬁts of VAC therapy include removal of ﬂuid from the extravascular space, improved circulation, enhanced granulation tissue formation, increased bacterial clearance, and hastening of wound closure. This article describes the mechanism of action of VAC therapy, reviews application techniques, and lists potential complications and contraindications.

At a Glance Equipment and Application Page 568

Beneﬁcial Effects and Mechanism of Action Page 572

Complications and Contraindications Page 576

aDr.

Lewis discloses that he has received ﬁnancial support from Arthrex Vet Systems and Imex Veterinary.

568

acuum-assisted closure (VAC) is a and promoting abscess formation.1,4 VAC noninvasive, active wound manage- therapy is applicable for the treatment of ment system that subjects a wound several wound types (BOX 1). A VAC system consists of several essenbed to subatmospheric pressure within a closed environment. Within this closed, tial elements: sterile open-cell polyurethane negative-pressure environment, VAC ther- foam (pore size: 400 to 600 μm), plastic apy removes fluid from the extravascular egress tubes, occlusive plastic adhesive space, improves circulation, and enhances film, suction tubing, a collection reservoir, the proliferation of granulation tissue.1–4 and an adjustable suction pump capable This article describes the necessary equip- of intermittent or continuous negative ment for, and method of applying, VAC pressures ranging from –50 to –200 mm therapy; reviews the mechanism of action Hg. These components are commercially and benefits; and describes contraindica- available (Kinetic Concepts, Inc. [KCI], San tions and complications. Antonio, TX; Smith and Nephew, London, England). Additional supplies that we have Equipment and Application found useful in applying VAC therapy Basic wound care principles must be fol- include a skin stapler, adhesive paste, and lowed before VAC therapy is initiated. adhesive spray (TABLE 1). Patients are hosProper debridement of devitalized tissue is pitalized for the duration of VAC therapy essential to eliminate any potential nidus (usually 3 to 7 days) and require frequent for bacterial growth and to allow suc- monitoring. An airtight seal is essential to maintain cessful wound closure after VAC therapy.4 Incomplete wound debridement before the continuous negative pressure and prevent application of VAC therapy may result in desiccation of the underlying tissue.1 In the proliferation of granulation tissue over dogs and cats, the hair on the skin adjacent necrotic tissue, delaying wound healing to the wound must be clipped to facilitate

Compendium: Continuing Education for Veterinarians® | December 2009 | Vetlearn.com

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CE Wound Closure Therapy

QuickNotes Basic wound care principles must be followed for all wounds before the application of VAC therapy.

MORE ON THE WEB A companion article on clinical applications of vacuum-assisted wound closure will be published in March 2010.

570

creation of this seal. The foam should be cut to conform to the shape of the wound and placed, fully expanded, directly within the wound so that it is in contact with the entire wound surface, especially the deep margins1,2,4 (FIGURE 1). A plastic, fenestrated egress tube or polyvinyl (red rubber) catheter (10 to 14 Fr) with several additional 2- to 3-mm fenestra-tions is then tunneled into a hole cut into the foam or placed between two pieces of foam.. To avoid pressure necrosis in tissue adjacent to the fenestrations, the egress tube should not be in direct contact with the wound bed.. When the foam and plastic tubing are in place,, the foam can be secured to the wound mar-gins using skin staples (FIGURE 1). To establish an airtight seal, we have found it helpful to apply adhesive spray and a ring of adhesive paste to the skin surrounding the wound before covering the foam and tubing with the adhesive plastic film. The film should extend several centimeters beyond the wound margins (FIGURE 1). The egress suction tube is attached to standard suction tubing and a collection reservoir, which is in turn connected to the vacuum pump with additional suction tubing. We use and recommend continuous suction. The continuous negative-pressure setting most commonly used during VAC therapy is –125 mm Hg.1–6 Initial animal studies showed improved blood flow and granulation tissue formation with intermittent suction (5 minutes on, 2 minutes off)2; however, human patients reported more discomfort when suction was applied intermittently than when it was continuous.1 In our experience, veterinary patients tolerate continuous suction well and do not require pain medication specifically for VAC therapy. When VAC therapy is used postoperatively over a closed incision to prevent seroma and edema formation, a lower negative-pressure setting of –50 mm Hg has been advocated.4 When VAC therapy is used in this manner, the foam can be cut and placed directly over the incision or, if the incision is on a limb, wrapped around the circumference of the limb. If the foam is wrapped circumferentially around a limb, it is essential to cover the entire limb distal to the incision, including the paw, with the foam to prevent a tourniquet effect.

Surgical Views is a collaborative series between the American College of Veterinary Surgeons (ACVS) and Compendium. Upcoming topics in this series include conventional foreign object removal and suspensory ligament rupture. All Surgical Views articles are peer-reviewed by ACVS diplomates. To locate a diplomate, ACVS has an online directory that includes practice setting, species emphasis, and research interests (acvs.org/VeterinaryProfessionals/FindaSurgeon).

When suction is applied, the foam should visibly collapse within the wound and take on a “raisin” appearance beneath the adhesive ﬁlm (FIGURE 1). The KCI and Smith and Nephew negative-pressure wound care units are equipped with alarm systems to detect air leakage. If one of these pumps is not being used, the appearance and texture of the foam must be checked frequently to ensure that there is no loss of suction. If the airtight seal is lost, measures must be taken to restore the vacuum immediately.

Compendium: Continuing Education for Veterinarians® | December 2009 | Vetlearn.com

Indications for VAC Therapya BOX 1

Large, open, contaminated wounds Skin avulsions Degloving injuries Abdominal and thoracic wounds (e.g., laparotomy surgical sites, open thoracic wounds) Surgical dehiscence Chronic nonhealing wounds Prevention of postoperative seroma and edema Bolster for skin grafts Myofascial compartment syndrome a

Our experience with the use of VAC therapy for these indications will be detailed in a companion article in March 2010.

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Caution: Federal law restricts this drug to use by or on the order of a licensed veterinarian. Indications: For use in dogs for correction of conditions associated with low circulating thyroid hormone (hypothyroidism). Dosages: The initial recommended daily dose is 0.1 to 0.2 mg/10 pounds (4.5 kg) body weight in single or divided doses. Dosage is then adjusted by monitoring the T4 blood levels of the dog every four weeks until an adequate maintenance dose is established. Administration: Thyro‑Tabs® may be administered orally or placed in the pet’s food. Warnings: The administration of levothyroxine sodium to dogs to be used for breeding purposes or in pregnant bitches has not been evaluated. There is evidence to suggest that administration to pregnant bitches may in some instances affect the normal development of the thyroid gland in unborn pups. How Supplied: 0.1 mg, 0.2 mg, 0.3 mg, 0.4 mg, 0.5 mg, 0.6 mg, 0.7 mg, 0.8 mg, and 1.0 mg tablets in 28, 120, and 1,000 count. READ PACKAGE INSERT FOR COMPLETE DIRECTIONS

FREE

CE Wound Closure Therapy Components Recommended for Application of VAC Therapy and Approximate Pricea TABLE 1

Component Sterile open-cell polyurethane foam (pore size: 400–600 μm) Plastic egress tube

QuickNotes VAC therapy increases wound circulation, accelerates granulation tissue formation, and removes excess ﬂuid from the extravascular space.

572

Costb $8.00/8" × 12" sheet $8.75

Occlusive plastic adhesive ﬁlm

$23.25

Skin staples

$23.00

Adhesive spray

$3.75c

Adhesive paste

$22.95

Suction tubing and collection reservoir

$20.00

Suction pump capable of continuous negative pressure

$54.00d

a Essential items are in bold. bPrices listed are based on costs charged to clients at the University of Florida

Veterinary Medical Center. c This cost is not billed to clients because one container can be used for

approximately 20 patients. d This is a daily fee assessed for continuous suction through either central

suction or a VAC machine.

The frequency of VAC bandage changes depends on the characteristics of the wound. VAC bandages are typically changed every 48 to 72 hours,3–5 although initial management of traumatic or highly contaminated wounds may require the bandage to be changed every 24 hours to allow adequate debridement.5,7,8 Culture and sensitivity testing and administration of appropriate antibiotic therapy are indicated for infected wounds. If VAC bandages are left in place for more than 4 to 5 days, granulation tissue may grow into the pores of the open-cell foam, requiring surgical removal of the foam bandage.1 Modiﬁcations to traditional VAC therapy have been introduced to treat highly infected wounds or wounds with resistant infections, including silver-impregnated foam (V.A.C. Granufoam Silver Dressing, KCI) and a system that combines negative-pressure wound therapy and antibiotic instillation (V.A.C. Instill, KCI).5 Early results of the use of these systems in highly infected wounds are promising, although no studies of their use been conducted in dogs.8–12 In dogs and cats, bandages can usually be changed with patients under heavy sedation.2 If

VAC therapy is used for long periods of time and multiple bandage changes are performed, the plastic adhesive film can be incised directly over the foam, which can then be removed through the fenestration in the film. Leaving the margins of the original film adhered to the skin reduces skin irritation and minimizes the discomfort experienced during bandage changes by avoiding pulling the film away from the skin. New adhesive film sheets are then placed over the previously applied bandage.7

Beneficial Effects and Mechanism of Action The uniform negative pressure applied to the wound bed by VAC therapy has several beneficial effects, including decreased interstitial edema, increased tissue blood flow, accelerated granulation tissue formation, increased bacterial clearance, and hastened wound closure.1,2 VAC therapy enhances the formation of granulation tissue by increasing capillary blood flow velocity, stimulating endothelial cell proliferation and angiogenesis, narrowing endothelial spaces, and restoring capillary basement membrane integrity.12 Decreased capillary permeability results in reduced edema formation, and the closed, negative-pressure system removes excess interstitial fluid, resulting in decreased local interstitial pressure and restoration of blood flow to previously collapsed vessels.2 An additional mechanism by which VAC therapy increases granulation tissue formation is through mechanical stresses exerted on the wound environment. VAC therapy mechanically stimulates cells by exerting tensile forces on the surrounding tissues.4 The concept that tissues respond to applied forces has long been recognized in relation to bone physiology (Wolff’s law) and is the basis of the Ilizarov technique for distraction osteogenesis.13 In wounds treated with VAC therapy, the cytoskeleton of cells exposed to subatmospheric pressure is altered, resulting in the release of intracellular second messengers and upregulation of cell proliferation.14 VAC therapy is also postulated to increase granulation tissue formation through the removal of substances (e.g., degradative enzymes, proteases, collagenases) that negatively affect wound healing.3 The ability of VAC therapy to enhance bacterial clearance has been debated.2,15–17 Initial animal studies comparing the bacterial clearance of VAC therapy with that of daily saline wet-

Compendium: Continuing Education for Veterinarians® | December 2009 | Vetlearn.com

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CE Wound Closure Therapy FIGURE 1 Method of VAC bandage application.

(A) A large thermal burn on the dorsum of an adult boxer. (B) One week after injury, the eschar has been debrided, leaving a large open wound. Polyurethane open-cell foam is placed within the wound.

(C) The margins of the wound are advanced and secured to the foam using skin staples. A polyvinyl catheter has been tunneled into the foam and exits the foam at the upper left wound margin. This catheter is connected to standard suction tubing, which is then connected to a collection reservoir and suction pump. (D) A ring of adhesive paste has been placed around the wound margins, the foam and surrounding skin have been sprayed with adhesive spray, and adhesive film has been placed over the foam and surrounding skin. Negative pressure (–125 mm Hg) has been applied to the bandage, and the foam has contracted beneath the film, taking on a raisinlike appearance and texture.

Approximately 6 weeks after the original injury, the wound is closed and healing appropriately. This wound required approximately 10 days of VAC therapy.

to-dry bandages showed a drop in quantitative bacterial counts in VAC-treated wounds and a peak in bacterial counts in the control group by day 5.2 However, clinical studies evaluating wounds treated with VAC therapy in human patients have failed to show a signiﬁcant reduction in total bacterial counts.16,17 Irrespective of

574

whether bacterial numbers are reduced, VAC therapy is able to improve a wound’s resistance to bacterial overgrowth through the creation of a healthier wound environment.16 VAC therapy is not, however, a substitute for proper wound management, and wounds must be appropriately debrided before VAC therapy application.

Compendium: Continuing Education for Veterinarians® | December 2009 | Vetlearn.com

Rekindle the warmth of friendship. Atopic dermatitis can disrupt even the best relationships. Restore their closeness by prescribing ATOPICA (Cyclosporine Capsules, USP) MODIFIED. Its targeted action gives dogs lasting comfort without the serious health risks associated with steroids. What could be better than bringing friends back together? As with all drugs, side effects may occur. In a field study, the most common side effects were gastrointestinal signs. Gingival hyperplasia and papillomas may also occur during the initial dosing phase. ATOPICA is a systemic immunosuppressant that may increase the susceptibility to infection. ATOPICA is not for use in reproducing dogs or dogs with a history of neoplasia. ®

See Page 576 for Product Information Summary

ATO090302A

Brief Summary: For full product information see product insert. Caution: Federal (USA) law restricts this drug to use by or on the order of a licensed veterinarian. Description: ATOPICA (cyclosporine capsules, USP) MODIFIED is an oral form of cyclosporine that immediately forms a microemulsion in an aqueous environment. Indications and Usage: ATOPICA is indicated for the control of atopic dermatitis in dogs weighing at least 4 lbs body weight. Dosage and Administration: The initial daily dose of ATOPICA is 5 mg/kg/day (3.3-6.7 mg/kg/day) as a single daily dose for 30 days. Following this initial daily treatment period, the dose of ATOPICA may be tapered by decreasing the frequency of dosing to every other day or two times a week, until a minimum frequency is reached which will maintain the desired therapeutic effect. ATOPICA should be given at least one hour before or two hours after a meal. If a dose is missed, the next dose should be administered (without doubling) as soon as possible, but dosing should be no more frequent than once daily. See Product Insert for dosing chart. Contraindications: ATOPICA is contraindicated for use in dogs with a history of neoplasia. WARNINGS: ATOPICA (cyclosporine) is a potent systemic immunosuppressant that may increase the susceptibility to infection and the development of neoplasia. Human Warnings: Not for human use. Keep this and all drugs out of reach of children. For use only in dogs. Precautions: Gastrointestinal problems and gingival hyperplasia may occur at the initial recommended dose. ATOPICA should be used with caution with drugs that affect the P-450 enzyme system. Simultaneous administration of ATOPICA with drugs that suppress the P-450 enzyme system, such as ketoconazole, may lead to increased plasma levels of cyclosporine. The safety and effectiveness of ATOPICA has not been established in dogs less than 6 months of age or less than 4 lbs body weight. ATOPICA is not for use in breeding dogs, pregnant or lactating bitches. Since the effect of cyclosporine use on dogs with compromised renal function has not been studied ATOPICA should be used with caution in dogs with renal insufficiency. There have been reports of convulsions in human adult and pediatric patients receiving cyclosporine, particularly in combination with high dose methylprednisolone. Killed vaccines are recommended for dogs receiving ATOPICA because the impact of cyclosporine on the immune response to modified live vaccines is unknown. As with any immunomodulation regimen, exacerbation of sub-clinical neoplastic conditions may occur. Adverse Reactions: A total of 265 dogs were included in the field study safety analysis. One hundred and eleven (111) dogs were treated with placebo for the first 30 days. For the remainder of the study, all dogs received ATOPICA capsules. Four dogs withdrew from the study after vomiting. One dog each withdrew from the study after diarrhea; vomiting, diarrhea and pruritus; vomiting, depression and lethargy; lethargy, anorexia and hepatitis; gingival hyperplasia, lethargy, polyuria/polydipsia and soft stool; seizure; sebaceous cyst; pruritus; erythema; or otitis externa respectively. Vomiting (30.9%) and diarrhea (20.0%) were the most common adverse reactions occurring during the study.In most cases, signs spontaneously resolved with continued dosing. In other cases, temporary dose modifications (brief interruption in dosing, divided dosing, or administration with a small amount of food) were employed to resolve signs. Persistent otitis externa (6.8%), urinary tract infections (3.8%), anorexia (3.0%), gingival hyperplasia (2.3%), lymphadenopathy (2.3%) and lethargy (2.3%) were the next most frequent adverse events observed. Gingival hyperplasia regressed with dose tapering. Owners of four dogs reported seizures while dogs were receiving ATOPICA. In one dog, seizures were the result of a brain tumor diagnosed one month into the study. Another dog experienced seizures before and after the study. The following clinical signs were reported in less than 2% of dogs treated with ATOPICA in the field study: constipation, flatulence, Clostridial organisms in the feces, nausea, regurgitation, polyuria/ polydipsia, strong urine odor, proteinuria, pruritus, erythema/ flushed appearance, pyoderma, sebaceous adenitis, crusty dermatitis, excessive shedding, coarse coat, alopecia, papillomas, histiocytoma, granulomatous mass or lesion, cutaneous cyst, epulis, benign epithelial tumor, multiple hemangioma, raised nodule on pinna, seizure, shaking/trembling, hind limb twitch, panting, depression, irritability, hyperactivity, quieter, increased light sensitivity, reluctance to go outside, weight loss, hepatitis. Clinical Pathology Changes: During the study, some dogs experienced changes in clinical chemistry parameters while receiving ATOPICA, as follows: elevated creatinine (7.8%), hyperglobulinemia (6.4%), hyperphosphatemia (5.3%), hyperproteinemia (3.4%), hypercholesterolemia (2.6%), hypoalbuminemia (2.3%), hypocalcemia (2.3%) and elevated BUN (2.3%). Post-approval Experience: Neoplasms have been reported in dogs taking ATOPICA, including reports of lymphosarcoma and mast cell tumor. It is unknown if these were preexisting or developed de novo while on ATOPICA. In post-approval drug experience reporting the following additional adverse reactions have been associated with ATOPICA administration in dogs: vomiting, diarrhea, depression/ lethargy, anorexia, pruritus, liver enzyme elevations, trembling, convulsions, polydipsia, polyuria, weight loss, hyperactivity, nervousness, neoplasia. To report suspected adverse reactions or for technical assistance, call 1-800-332-2761. Manufactured for: Novartis Animal Health US, Inc. Greensboro, NC 27408, USA NADA 141-218, Approved by FDA ©2009 Novartis Animal Health US, Inc. ATOPICA is a registered trademark of Novartis AG. NAH/ATO-GC/BS/5 07/08

FREE

CE Wound Closure Therapy Another advantage associated with the use of VAC therapy is the acceleration of wound closure.17 The mechanical forces and improved granulation tissue formation hasten wound contraction, resulting in earlier closure.17 The reduction in time needed to achieve a healthy wound bed, along with the need for fewer bandage changes under sedation, may offer cost savings for VAC therapy compared with conventional dressings that must be changed once or twice daily.17

Complications and Contraindications Complications associated with VAC therapy tend to be minor and easily managed. In our experience, the most common complication is the loss of the airtight seal, which can often be corrected by adding an additional layer of adhesive film. Local dermatitis associated with the bandage is also common but tends to be self-limiting. A significant complication resulted from leaving a VAC therapy dressing in place for 5 days. Granulation tissue grew into the pores in the open-cell foam and necessitated surgical excision of the foam to completely remove the polyurethane fibers. Few complications have been reported in human patients undergoing VAC therapy.5 The most common complication is mild skin irritation from contact with the foam.1,4 Two cases of toxic shock syndrome associated with VAC therapy use have been reported.18 Additionally, chronic complications may result from pieces of foam being left within the wound.5 VAC therapy should be used with caution in hemodynamically unstable patients because

large volumes of ﬂuid can be removed during treatment.3,4 There are several contraindications to VAC therapy. The VAC system has a limited ability to debride wounds, and it will not remove devitalized or necrotic tissue. Thus, VAC therapy should not be used in lieu of proper surgical debridement.1,4 The treatment of osteomyelitis with the VAC system alone is also contraindicated.4,19 The VAC therapy system should not be used in wounds contaminated with malignant neoplastic cells because the application of the VAC therapy bandage will likely increase blood ﬂow and stimulate cellular proliferation within the wound bed.1,4 Finally, care should be taken when placing VAC therapy dressings near exposed arteries and veins. It is possible for the foam to erode through exposed vessels, resulting in extensive blood loss.4,5 Similarly, VAC therapy dressings should be used with caution in patients with coagulopathies or active bleeding.4,5

Conclusion VAC therapy increases local blood ﬂow and enhances granulation tissue formation in wounds, accelerates wound contraction, and removes excessive ﬂuid from wounds. After adequate debridement, VAC therapy can be applied to a wide variety of wounds.

ON THE WEB

The references for this article are available at Vetlearn.com.

CE TEST 2 This article qualiﬁes for 3 contact hours of continuing education credit

3 CE CREDITS

from the Auburn University College of Veterinary Medicine. Subscribers must take individual CE tests online and get real-time scores at Vetlearn.com. Those who wish to apply this credit to fulﬁll state relicensure requirements should consult their respective state authorities regarding the applicability of this program.

576

Compendium: Continuing Education for Veterinarians® | December 2009 | Vetlearn.com

Index to Advertisers For free information about products advertised in this issue, e-mail the product names to productinfo@CompendiumVet.com. Company

Product

Page #

AAHA

Long Beach 2010 Conference

573

Abbott Animal Health

SevoFlo

544, 545

Antech Diagnostics

FastPanel PCR

551

Banﬁeld, the Pet Hospital

We Believe in Vets

541 (US only)

Bayer HealthCare Animal Health

Advantage Multi for Dogs

552, 553

resQ

539

“A Perfect Fit”

548–549

Boehringer Ingelheim Vetmedica

ProZinc

555, 556

Prescription Diet j/d Canine

Inside front cover (Canada only)

Intervet/Schering-Plough Animal Health

Canine Inﬂuenza Vaccine

Back cover

Lloyd, Inc.

Thyro-Tabs

571

Northgate Veterinary Supply

Glass cage doors and rod gates

578

Novartis Animal Health

Atopica

575, 576

P&G Pet Care

NAVC/WVC Symposia

565

Prostora MAX

563 Inside front cover (US only)

Hill’s Pet Nutrition

Sound-Eklin

Veterinary Imaging

VCA Antech

Hospital Purchase Program

569

Vet-Stem, Inc.

Credentialing Courses

Inside back cover

Veterinary Learning Systems

Vetlearn.com

567, 577

Vetstreet

Pet Portals

558, 559

Western Veterinary Conference

2010 Conference

561

WhereTechsConnect.com

Job Marketplace

578

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CLASSIFIEDS VETERINARIANS WANTED MARYLAND – Experienced Associate Veterinarian needed for high-energy, high-quality small animal exclusive veterinary hospital situated on 30 beautiful acres in Urbana, MD. Our facility provides state-of-the-art diagnostic equipment, two surgical suites, an established boarding resort, and a focus on preventative medicine as well as creating an exceptional client/ patient experience. Candidates must have excellent client communication skills, be able to work independently and feel competent performing various common surgical procedures. We invite you to learn more by contacting Beth Finnegan, CVT, RVT, Human Resource Manager, or at bﬁnnegan@ greenbriarpethospital.com.

VETERINARIANS WANTED TEXAS Associate Veterinarian Full-time position for enthusiastic individual with excellent work ethic. Busy small animal clinic located in thriving West Texas has full diagnostic and surgical capabilities, including ultrasound, endoscopy, and neurosurgery. All interested applicants welcome. Call 432-332-5782

NORTH CAROLINA – Well-established, 24-hour, AAHAaccredited small animal hospital in central North Carolina needs an emergency/critical care veterinarian and an associate veterinarian. Located only hours from the mountains and coastlines, our busy, progressive, and expanding five-doctor practice is fully equipped and staffed by 25 highly motivated veterinarians, technicians, and lay staff. Established more than 27 years, our hospital has an excellent client base and strong emphasis on quality care. Work in a great practice environment with an excellent opportunity for career development. Competitive salary and benefits include 401(k), profit sharing, CE, and insurance. Experience preferred. Send resume to Dr. Karl B. Milliren, 303 National Highway, Thomasville, NC 27360; email tvh303@cs.com; fax 336-475-0140.

TEXAS – Gainesville, enthusiastic, compassionate, dedicated full-time veterinarian needed for rapidly growing, 2½ doctor small animal practice, 1 hour north of Dallas/ Fort Worth. Must be well versed in client education and have exceptional standards for animal care and customer service. Fully-equipped, new hospital with easy access to board-certiﬁed specialists. Opportunity for exotic animal and equine work if interested. Reasonable hours, (average work week 32-36 hours), competitive salary and beneﬁts with buy in potential for the right individual. Excellent medical and communication skills a must. Email resume to: dianalane@independenceanimal.com, or fax to attention Diana Lane 940-668-8525.

It's FREE! 578

Compendium: Continuing Education for Veterinarians® | December 2009 | Vetlearn.com

TEXAS – It all begins here at DCCCD. Cedar Valley College is currently accepting applications for the Director, Veterinary Technology position. Requirements: Doctor of Veterinary Medicine, DVM plus 3 years teaching experience and administrative responsibility or comparable experience. Ability to utilize computer technology to access data, maintain records, generate reports and communicate with others. Requires technical communication skills to deal with veterinary technology faculty and other health professionals and individuals from diverse socio-economic backgrounds. Official transcript will be required.Salary: $51,876 $90,783 annually, depending on education and experience (comprehensive benefits package). Application requirements: Official DCCCD application for employment (www.jobs.dcccd.edu), resume, unofficial copy of graduate transcripts. Deadline for all applications (electronic/ non-electronic) and other required documents is open until filled. Resume and unofficial transcripts may be faxed to 972-860-8279, emailed to CVCHR@dcccd.edu, delivered in person or mailed to: Cedar Valley College, Human Resources, 3030 North Dallas Ave., Lancaster, TX 75134. Please include position number (030909051) on all documents submitted. For complete job description information and online application please visit our web site at: www.dcccd.edu/Business+Community/ jobs.htm. To send supplemental information email apply@dcccd.edu. Employment opportunities are offered by the Dallas County Community College District without regard to race, color, age, national origin, religion, sex, disability or sexual orientation.

CONTINUING EDUCATION

CLIENT HANDOUT

What You Should Know About

Feline Upper Airway Infections Sneezing? Coughing? Your Kitty May Need More Than Chicken Soup! Cats, especially kittens, often get upper airway (respiratory) infections. If your cat shows any signs of respiratory illness, such as sneezing, wheezing, “gummy” eyes, or a runny nose (see box below), make an appointment to have him or her evaluated right away. Depending on their cause, upper airway infections can quickly become serious, especially in kittens. In adult cats, untreated infections can lead to other (secondary) infections or damage delicate sinuses, resulting in chronic problems. Most feline upper airway infections are caused by viruses, but some cats develop secondary bacterial infections. Signs of upper respiratory disease can also be linked to other serious problems, like allergies, dental disease, cancer, or the presence of a foreign object in the nose or the back of the mouth.

What Are the Signs? Signs of upper airway infection in cats vary depending on what is causing them. The most common signs are: Sneezing Watery or mucous discharge from the eyes or nose Cough Fever Lethargy Loss of appetite or weight Less common signs include: Hoarse “voice” Change in facial shape Ulcers in the mouth or eyes

If your cat shows any signs of respiratory illness, make an appointment to have him or her evaluated right away.

What Causes Feline Upper Airway Infections? Approximately 90% of all upper airway infections in cats are caused by two common viruses: feline herpesvirus-1 and feline calicivirus. Feline herpesvirus is related to the virus that causes cold sores and chickenpox in people; however, people cannot get sick from the feline virus. Upper airway infections in cats can also be caused by fungi or bacteria. It is common for cats to be co-infected—infected with more than one agent (e.g., a virus and a bacterium) at the same time—which can make treatment and recovery longer and more difﬁcult.

How Are These Diseases Spread? Feline upper airway infections are spread the same way as the common cold: a healthy cat comes in contact with an object that has been used by an infected cat—for example, a shared food bowl or toy. Frequently disinfecting shared items can help reduce transmission risk. Feline calicivirus can also be spread when a healthy cat uses the same

Produced in association with Vetstreet. A downloadable version of this client handout is also available at Vetlearn.com.

12/09

CLIENT HANDOUT

Feline Upper Airway Infections litterbox as an infected cat. And, just like the common cold, your hands can play a role in spreading these viruses, so if you have or touch a sick cat, wash your hands before touching another cat! Even after they are no longer sick, many cats that have been infected with feline herpesvirus and calicivirus can transmit these viruses to other cats. Therefore, seek professional veterinary advice before introducing a new cat with an unknown vaccination history into your house or before placing your cat in an unfamiliar setting with other cats, such as a boarding facility.

How Can I Keep My Cat Healthy? Cats that are kept indoors are at lower risk of contracting upper airway diseases. Cats that are allowed outside; have recently been in a shelter, boarding facility, or cattery; or live in a multicat household are at higher risk of contracting these diseases. Kittens, because of their immature immune systems, are also at higher risk. Vaccines are available to help prevent or reduce the severity of the most common infections. Many vaccines may not be 100% effective in preventing a disease, but they do help limit how sick your cat becomes if it is infected. See the box about current vaccination guidelines regarding which vaccines cats should get and how often.

What Do I Do If My Cat Is Already Sick? Diagnosing the exact cause of an upper airway infection can be difﬁcult because many cats are co-infected. When you bring your

Raising The Red Flag Signs of upper airway disease can be caused by underlying conditions, such as nasal tumors or dental disease. If your cat’s illness lasts an unusually long time or is accompanied by unusual pain, facial deformity, signiﬁcant weight loss, or some other odd sign, additional diagnostic tests may be needed to rule out other problems.

Produced in association with Vetstreet. A downloadable version of this client handout is also available at Vetlearn.com.

12/09

cat to the veterinary ofﬁce, it helps if you can remember what vaccinations your cat has had, when your cat might have been exposed to an infected cat, and when your cat began to show signs of being sick. Some laboratory tests may be necessary to help with the diagnosis.

Many sick cats lose their appetite because nasal congestion affects their sense of smell, so these cats may need to be tempted with baby food or another delicious treat. As in people, very few drugs can control viral infections, so treatment typically consists of keeping your cat warm, comfortable, and eating and drinking properly. Many sick cats lose their appetite because nasal congestion affects their sense of smell, so these cats may need to be tempted with baby food or another delicious treat. Discharge from the nose and eyes should be gently cleared away if the cat will allow it, and any lesions in the mouth or eyes should be treated. You may be given a prescription for a broad-spectrum antibiotic to help combat any secondary bacterial infections. Dehydration can be a problem in seriously ill cats, so ﬂuid therapy may be called for in some cases.

Vaccination Guidelines The American Association of Feline Practitioners (AAFP; catvets.com) considers feline herpesvirus-1 and feline calicivirus vaccines as core, meaning that they should be given to virtually every cat. They are usually given in a single combination vaccine. The current AAFP recommendations include vaccinating kittens as young as 6 weeks, accompanied by a series of booster shots. The number of boosters depends on the kitten’s age when the ﬁrst shot is given.

want to learn about stem cells? sign up at

NAVC or WVC

NAVC

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Credentialing Course: January 20th, 2010 ¦ 8:30am- 12:30pm Hands On Wet Lab: January 20th, 2010 ¦ 1:30pm- 5pm

WVC

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photo: JoshDubya

With the introduction of the first vaccine for canine influenza,

only the love is contagious. Now you can provide your patients with more comprehensive protection against respiratory infection. Love is not the only thing in the air. Canine influenza virus (CIV) has been confirmed in dogs across 30 states and the District of Columbia, and its prevalence is rising.1 And because most dogs are naive to the virus, virtually every naive dog exposed will become infected.2 CIV is highly contagious and sometimes deadly. Clinical signs associated with CIV can be confused with kennel cough making accurate diagnosis difficult. Now you can broaden the respiratory protection you currently offer to patients with the addition of the first vaccine for canine flu, Canine Influenza Vaccine, H3N8. Canine Influenza Vaccine, H3N8 —a killed virus vaccine from Intervet/Schering-Plough Animal Health—significantly decreases clinical signs of disease and reduces viral shedding, and its safety has been confirmed in a study involving more than 700 dogs.3

Notice: This product license is conditional. As with all USDA conditionally licensed products, data submitted to the USDA supports a reasonable expectation of efficacy. Safety was established in trials involving more than 700 dogs.

So while CIV, like love, can be easily spread and hard to identify, it no longer has to be so overwhelming. To learn more, contact your Intervet/Schering-Plough Animal Health representative, visit www.doginfluenza.com, or call our technical services team at 800-224-5318.

References: 1. Syndromic surveillance data of Cynda Crawford, DVM, PhD, University of Florida, and Edward Dubovi, PhD, Cornell University. 2. Key facts about canine influenza. CDC Website. Available at: http://www.cdc. gov/flu/canine. Accessed May 1, 2009. 3. Data on file, Intervet/Schering-Plough Animal Health. Copyright © 2009 Intervet International B.V. All rights reserved. SPAH-VC-284:9412