MAY-JUNE 2013
Deactivation of sodium tetradecyl sulphate injection by blood proteins PAGE 8
Anatomy and embryology of the small saphenous vein, nerve relationships and implications for treatment PAGE 14
may-jun ‘13
contents
Deactivation of sodium tetradecyl sulphate injection by blood proteins Contributing Editor/Reviewer:
From the Editor-in-Chief Dr. Nick Morrison
Neil Sadick , MD, FACP, FACPh, FAAD, FAACS
5
Associate Editor: Ted King MD, FAAFP, FACPh
8
Foot-sparing postoperative compression bandage: a possible alternative to the traditional bandage
Anatomy and embryology of the small saphenous vein, nerve relationships and implications for treatment
Contributing Editor/Reviewer: Hugo Partsch, MD
Contributing Editor/Reviewer: Mark Isaacs, MD
Associate Editor: Mitchell Goldman, MD, FACPh
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Associate Editor: Pauline Raymond-Martimbeau, MD, FACPh
Prevention of venous thromboembolism: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy Contributing Editor/Reviewer: Amjad T. AlMahameed, MD, MPH Associate Editor: Stephanie Dentoni, MD
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the world of vein care unites in Boston this September
Hosted by the American College of Phlebology in conjunction with the International Union of Phlebology, the XVII UIP World Meeting will bring together respected faculty, physicians and health care professionals from across the globe this September 8-13 to showcase the most advanced research, technology and treatments in the field of vein care.
This truly historic event will include sessions covering the wide spectrum of phlebology, including: + More than 300 internationally recognized speakers
+ More than 85 event exhibitors showcasing the world's
from around the world
+ Innovative and clinically relevant educational sessions + Hands-on simulation workshops and demonstrations with international faculty
+
most advanced products, pharmaceuticals and medical devices Opportunities for all levels of skill, from basic through advanced, to improve your practice and patients' care
NAL NATIO E DE PHL TER
LOGIE EBO
UNION IN
Join the ACP at the XVII UIP World Meeting in Boston, September 8-13 for this extraordinary event.
A
N AL
HL
EB
RN
OLO
GY
INTE TIO
UNIO N OF P
World Meeting of the International Union of Phlebology /// September 8–13, 2013 Hynes Convention Center • Boston, Massachusetts • USA
HOSTED BY
510.346.6800 | www.uip2013.org | www.phlebology.org advancing vein care
2013 Compression Hosiery and support Wear Buyer’s Guide n
Everything you need to know about over-the-counter and medical compression therapy products
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Photos and detailed product information from eleven manufacturers
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Compression stockings, pantyhose, thigh-highs, maternity, travel and sports socks, plus lymphedema products and armsleeves
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Find tREatmEnt solutions FoR Tired & Achy Legs • Varicose Veins • Vascular Disease • Swelling & Lymphedema • Ulcers • Fragile/Sensitive Skin • DVT Prevention
View past issues of Phlebology Forum at
www.phlebology.org
disclosure of interests
Name
ACP Role
Date Submitted
Disclosure
Stephanie Dentoni, MD
Recruitment & Retention (Chair)
6/25/12
Nothing to Disclose
Mark Forrestal, MD, FACPh
ACP
6/25/12
New Star Lasers Cooltouch: Speaker, Trainer
Mitchel Goldman, MD, FACPh
Phlebology Forum Task Force
2/14/2013
American Society for Dermatologic Surgery, President-Elect; Merz Aesthetics/Kruesler, Consultant
Jean-Jerome Guex, MD, FACPh
ACP BOD, Communications, Standing Committee, Leadership Development, UIP 2013 Task Force, AMA HOD Task Force, International Affairs (Chair),
6/14/12
Kreussler: Speaker; Sigvaris: Speaker, Investigator, Consultant; Innotech: Principal Investigator; Pierre Fabre: Consultant; Boerighr Ingelheim: Consultant, Medical Writer; Servier: Investigator, Consultant, Speaker
Lowell Kabnick, MD, FACS, FACPh
UIP 2013 Task Force
7/17/12
Angiodynamics: Consultant, Shareholder, Patent; Vascular Insights: Scientific Advisory Board
Neil Khilnani, MD, FACPh
ACP BOD, Member Services (Chair)
7/24/12
Sapheon: Data Safety Board Member
Ted King, MD, FAAFP, FACPh
ACP BOD, Leadership Development, PES-QM Task Force, Public Education
6/14/12
BTG: Investigator; Merz: Speaker
Mark Meissner, MD
ACP BOD, Education Standing Committee
7/13/12
Nothing to Disclose
Nick Morrison, MD, FACS, FACPh
UIP 2013 Task Force (Chair), Phlebology Forum Task Force (Chair), Annual Congress Planning Committee (Chair)
6/13/12
Medi: Speakers Bureau; Merz: Speakers Bureau; Sapheon: Principle Investigator; VeinX: Scientific Advisory Board
Eric Mowatt-Larssen, MD
ACP CME Committee
6/25/12
BTG International, Inc.: Consultant
Diana Neuhardt, RVT, RPhS
ACP BOD, Member Services, Audit, UIP 2013 Task Force, Phlebology Forum Task Force, Veinline, Recruitment & Tetention, CME, Distance Learning, Public Education (Chair)
6/15/12
Nothing to Disclose
Pauline RaymondMartimbeau, MD, FACPh
UIP 2013 Task Force
6/22/12
Nothing to Disclose
6
From the
Editor-in-Chief Dear Readers In this issue of Phlebology Forum you will find a number of topics related to deep and superficial venous problems, many of which expand our understanding of what we see and can do on a practical basis in daily work. Included are an investigation into the deactivation of STS sclerosant which may help explain the varied clinical outcomes we all see; an introduction to the vagaries of small saphenous vein and associated nerve anatomy and their clinical implication; relevant clinical information regarding post-treatment compression therapy which adds to the dogmachallenging discussion of compression; and an excellent analysis of the ACCP guidelines for thromboprophylaxis. And finally, I will beat the drum on behalf of the ACP and the Organizing Committees for the UIP XVII World Congress in Boston, and I can promise this meeting will be one of the best “vein� meetings you have ever attended and will greatly exceed your expectations. The countdown is now less than 3 months and I have only three other things to say about the meeting: BOSTON! BOSTON! BOSTON! Nick Morrison, MD Editor-in-Chief Phlebology Forum
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sodium tetradecyl sulphate
Deactivation of
injection by blood proteins Watkins MR. Eur J Vasc Endovasc Surg. 2011 Apr;41(4):521-5. doi: 10.1016/j.ejvs.2010.12.012. Epub 2011 Jan 22. Contributing Editor/Reviewer: Neil Sadick, MD, FACP, FACPh, FAAD, FAACS Associate Editor: Ted King MD, FAAFP, FACPh
COMMENTARY The clinical phlebologist is well aware that sclerosants act at limited areas of clinical activity from the point where they are injected. In the past, it was felt that this clinical observation was related to the dilution of the sclerosant and its subsequent decreased potency in this regard, based solely upon concentration/sclerosant endothelial interaction
in practical use, it would take less than 0.5% ml of whole blood to deactivate 1 ml of 3% STS
kinetically.
In addition, a commonly known observation is that foam sclerosants manifest greater potency and also have more significant distal watershed-type effect. With these tenets in mind, the article entitled “Deactivation of sodium tetradecyl sulphate injection by blood protein” brings new insight and rationale into the actual pathophysiologic mechanisms of this clinical observation.
The present study looked at the volume of blood required to inactivate 1ml of 3% sodium tetradecyl sulphate. This was accomplished by measuring the concentration of sodium tetradecyl sulphate (STS) remaining in the active state in an in-vitro stock solution after adding increasing volumes of solution containing either bovine serum albumin or red blood cells or a mixture of both components. The two methodologies utilized to assess the results included autotritation and colorimetry.
Results of the aforementioned study showed that STS is deactivated by blood proteins in a linear fashion. The protein solution utilized seemed to make little difference, with approximately 2 ml of 4% protein solution deactivating 1 ml of a 3% STS solution.
The authors hypothesized that titration measured the free STS remaining in solution after the addition of blood proteins which would bind and deactivate the STS and this correlates with clinical activity. These results suggest that in practical use, it would take less than 0.5% ml of whole blood to deactivate 1 ml of 3% STS which would explain why an empty vein technique is important when injecting liquid sclerosant in the varicose veins, a concept that is well-documented in clinical practice since its description by Orbach.1
This would explain the noted limited distance of clinical efficacy of injected liquid sclerosants. Limitation of this study would include its in-vitro design and qualitative visual assessment as related to the colorimetric assay employed in the study design. The authors also confirm that it was difficult to visually determine the end point of titration with increasing volumes of blood proteins, which is why the average of up to four individual readings was utilized. 1 Orbach EJ. Sclerotherapy of varicose veins—utilization of an intravenous air block. Am J Surg 1944;LXVI(3):362–6.
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Therefore, the results should be interpreted as a guide rather than an exact figure.
The aforementioned article is of great clinical importance to the practicing phlebologist although it is not without limitations in terms of its design. This is one of the few articles in the literature which would attempt to understand physiologic interactions between liquid sclerosants and blood vessels and helps to explain many of the clinical observations noted by the practicing phlebologist.
The characteristics of sclerosants that the practicing phlebologist considers in choosing an agent for daily clinical practice include efficacy, which is often dependent upon its strength and thus the ability to induce pan endothelial destruction and its distal downstream clinical efficacy from the site of initial injection.2 Other considerations include its minimal sclerosant concentration, which will achieve pan endothelial destruction.3 Allergenicity and side effect profiles are important considerations in this regard.4
Other investigators have utilized cell lysis and human blood plasma looking at the lytic effect of STS on red blood cells, platelets and cultured endothelial cells.5 The main difference between the other studies and this work is that in other studies the lytic effects of the sclerosants on blood and endothelial cells in the presence of blood proteins were measured, whereas the present study quantifies the residual STS remaining after the addition of protein in a standard STS solution. However, with analysis of both sets of results it is clear that a low volume of blood (0.50 ml) is enough to neutralize 1 ml of 3% STS.
There are several clinical implications that can be taken from these studies. First, displacement of blood prior to treating a vein (Empty Vein Technique) may improve clinical efficacy. Second, foam sclerotherapy, which displaces more blood than liquid sclerosants, may explain its greater efficacy. However, this is less obvious with larger vessels where more treatment may be necessary because foam is less efficient at displacing blood as veins get larger.
Finally, repeated puncture instillations at frequent intervals may be more effective in treating larger veins because of the displacement of blood, and the practitioner may even consider utilizing tumescent techniques to decrease red blood cell volume as an additional augmenting maneuver.6
In summary, it appears from this and other published studies and clinical experience that it is a combination of chemical interactions and host factors that determine clinical outcomes with regard to the utilization of liquid sclerosants. 2 Murad MH, Coto-Yglesias F, Zumaeta-Garcia M, Elamin MB, Duggirala MK, Erwin PJ, Montouri VM, Gloviczki P. A Systematic review and meta-analysis of the treatments of varicose veins. J. Vasc Surg. 2011; 53(5 Suppl): 495-655. 3 Sadick NS, Choosing the appropriate sclerosant concentration for vessel diameter. Dermatol Surg 2010;36 Suppl 2976-981. 4 Cavezzi A, Parsi K. Complications of foam sclerotherapy. Phlebology 2012; 27 Suppl 146-51. 5 Parsi K, Exner R, Conner DE, Herbert A, Ma DDF, Joseph JE. The lytic effects of detergent sclerosants on erythrocytes, platelets, endothelial cells and microparticles are attenuated by albumin and other plasma components in vitro. Eur J Vasc Endovasc Surg 2008; 36(2): 216-223. 6 Ramelet A-A. Sclerotherapy in tumescent anesthesia of reticular veins and telangiectasia’s. Dermatol Surg 2012; 38(5): 748-751.
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Foot-sparing postoperative compression bandage: a possible alternative to the traditional bandage Author: Ricci S, Moro L, Trillo L, Incalzi RA. Phlebology. 2013 Feb;28(1):47-50. Contributing Editor/Reviewer: Hugo Partsch, MD Associate Editor: Mitchell Goldman, MD, FACPh
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Abstract Objectives: the aim of this study was to evaluate the efficacy and tolerability of foot sparing bandages after varicose vein surgery performed in CEAP C2 patients. Methods: 90 consecutive lower extremities in 129 patients, for whom different kinds of varicose vein surgery were performed, received inelastic footsparing bandages for one week. The bandages consist of thin polyurethane under- wraps, cotton pads selectively placed over operated tracks and of 10 cm wide adhesive bandages (Fortelast® Lohmann). In order to prevent slippage acrylic glue wraps are attached to the skin at the proximal end of the bandages. Patient’s satisfaction, efficacy and local effects were systematically documented. Results: High satisfaction was achieved. Measurement of the bandage pressures showed mean values of 25
foot-sparing inelastic bandages after varicose vein surgery are effective, cheap and well tolerated at least in a large proportion of mobile and active patients
mmHg are reported in the supine position, 30 mmHg in standing and 35 mmHg during walking. Four of the first 20 cases experienced a slight morning oedema of the foot, which disappeared while walking. Therefore, in the remaining cases the foot and distal limb were covered with a custom short tubular-shaped ‘sock’ providing 10 mmHg compression, only during the first 24 hours. Conclusion: The described foot-sparing inelastic bandages after varicose vein surgery are effective, cheap and well tolerated at least in a large proportion of mobile and active patients who do not show skin changes in the gaiter area.
Commentary In the last few years the value of compression after varicose vein procedures has been questioned by several investigators who used compression hosiery. Even TED stockings were applied which are definitely too weak to reduce the venous diameter of disconnected superficial veins in the upright position.1 On the other hand strongly applied conventional bandages
1 Partsch H, Mosti G, Uhl JF. Unexpected venous diameter reduction by compression stocking of deep, but not of superficial veins. Veins and Lymphatics 2012; 1:e3 online.
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in addition to the application of local pads over the treated areas were shown to have considerable benefits concerning a reduction of pain and hematoma formation.2,3 The reported method of applying bandages starting above the ankle and sparing the foot offers especially the advantages that the movement of the ankle joint remains unimpeded and that patients are able to put on and to wear their normal shoes. Slight edema distal to the bandage may occur after rest but disappears quickly as soon as the patient starts walking. As the authors have shown this swelling may be prevented by light compression socks. Using inelastic compression material offers the advantage of achieving higher pressures in the upright position and during walking while the resting pressure stays in a comfortable range. We use foot-sparing compression bandages mainly after (foam-) sclerotherapy of large tributaries and after phlebectomy in the same way as the authors, just with higher pressures. The positive experience of the authors challenge the dogma that leg compression needs to provide a pressure gradient and shows that in mobile patients, even without any compression of the gaiter area, no adverse “strangulation effects� occur. It has been demonstrated that compression pressure which is higher at calf than at gaiter level is also more effective in enhancing venous pump function4. We are grateful to the authors for reminding us of this very efficient way of compression which can be used in a large proportion of patients after venous stripping, phlebectomy and endovenous procedures.
2 Lugli M, Cogo A, Guerzoni S, Petti A, Maleti O. Effects of eccentric compression by a crossed-tape technique after endovenous laser ablation of the great saphenous vein: a randomized study. Phlebology. 2009 Aug;24(4):151-6. 3
Mosti G, Mattaliano V, Arleo S, Partsch H. Thigh compression after great saphenous surgery is more effective with high pressure. Int Angiol. 2009 Aug;28(4):274-80.
4 Mosti G, Partsch H. High compression pressure over the calf is more effective than graduated compression in enhancing venous pump function. Eur J Vasc Endovasc Surg. 2012 Sep;44(3):332-6.
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Anatomy and embryology of the small saphenous vein, nerve relationships and implications for treatment Author: Uhl JF, Gillot C Phlebology 2013;28:4-15 Contributing Editor/Reviewer: Mark Isaacs, MD Associate Editor: Pauline Raymond-Martimbeau, MD, FACPh
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COMMENTARY Treatment of the small saphenous vein is known to be challenging, both because of the highly variable anatomy of the vein and because of vulnerability of adjacent nerves and arteries to injury. Sural nerve injury and post operative paresthesia are two of the most common complications of treatment.1,2Surgeons traditionally have limited excision of the vein to a proximal segment and rarely if ever attempt to fully expose the popliteal vein in an effort to prevent neurological or arterial complications. This anatomical review by Uhl and Gillot is fascinating in its detail and highly relevant to the surgeon or nonsurgeon phlebologist approaching treatment of the small saphenous vein. The authors are to be commended for providing such an enlightening treatise on the known embryology and anatomy of the vein, with clearly delineated correlations between the described anatomy and possible treatment complications.
Going beyond the usual text descriptions, the authors make liberal use of diagrams and well labeled anatomical dissections to illustrate “high risk zones”: the ankle, the “apex of the calf”3, and the popliteal fossa. For example, at its termination the arch of the small saphenous vein crosses close to the tibial and medial gastrocnemius nerves. The sural nerve and two
...a thorough knowledge of the small saphenous vein and it’s surrounding structures remains mandatory. This paper should have a prominent place in the library of all physicians treating small saphenous venous insufficiency
“companion” vessels are shown to be in close proximity to the small saphenous vein below the calf muscles. In the ankle the origin of the vein is deep below the fascia and plexiform, with the nerve once again very closely associated.
The authors, however, go beyond their anatomical descriptions to draw conclusions about clinical practice. They state, for example, that the possible existence of a short saphenous artery poses a “high risk for injection of a sclerosing 1 Van Groenendael L, et al. Conventional surgery and endovenous laser ablation of recurrent varicose veins of the small saphenous vein: a retrospective clinical comparison of assessment of patient satisfaction. Plebology 2010;25:151-157 2 Gibson K, et al. Endovenous laser treatment of the short saphenous vein: Efficacy and complications. J Vasc Surg April 2007 45;4:795-800 3 In order to prevent confusion amongst English language readers it should be noted that “the apex of the calf” is an anatomical term used in several places in this paper by Gillot to refer to the location of the junction between the muscle of the calf and the Achille’s tendon, not the highest point of the calf.
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agent”, that “a good rule for endovenous laser treatment is to remain at least 4 cm below the popliteal crease to avoid a thermal injury of the nerves” and that a detailed “triple check” by duplex ultrasound of venous flow and nearby nerves and arteries is the “best way to reduce the risk of severe arterial or nerve complications.” While such conjecture is very reasonable and intuitively appealing given the anatomical relationships so carefully delineated in the article, there is a lack of documentation to support these conclusions. Regarding the recommendation for the type of duplex examination they describe, the scarcity of ultrasonographers adequately trained and skilled enough to identify not only superficial veins and tributaries but nearby nerves and small arteries makes following their recommendations utopian. As one author put it, nerves in the area of the popliteal fossa are, “always visible, never seen”.4
While good comparative studies are lacking, a recent review of the literature on treatment of the small saphenous vein would appear to confirm that endovenous treatment techniques including radiofrequency heat ablation, laser ablation and ultrasound guided foam sclerotherapy carry less risk of complications than surgery with better treatment outcomes.5 One prominent surgeon has gone so far as to declare surgery for small saphenous reflux to be obsolete!6 The explanation may lie not only with the lack of perivenous trauma but also with the use of tumescent anesthesia. We know that the advent of the use of tumescent anesthesia prior to endovenous catheter heat ablation treatment of the great saphenous vein resulted in a drop in neurological complications, presumably because properly injected tumescent fluid not only provides anesthesia, vein compression and a fluid heat “sink” but possibly also because it peels adjacent nerves and arteries away from the wall of the target vein. One might legitimately question whether the authors’ clinical guidelines are completely justified when tumescent anesthesia is properly administered prior to treatment. Certainly it is better to err on the side of caution, however, by keeping in mind the authors’ high risk zones even when liberal tumescent anesthesia has been used.
Unfortunately, there are many surgeons who have adopted endovenous treatment techniques but are unwilling or unable to wean themselves from the operating room and general anesthesia. Likewise, proper administration of tumescent anesthesia under ultrasound guidance is a challenging skill to learn even for those motivated to adopt it, and heat ablation done under tumescent anesthesia is far from risk free. Some practitioners do not use direct real-time ultrasound guidance during their procedures. For these reasons amongst others a thorough knowledge of the small saphenous vein and its surrounding structures remains mandatory. This paper should have a prominent place in the library of all physicians treating small saphenous vein insufficiency.
4 Ricci S. Ultrasound Observation of the Sciatic Nerve and Its Branches at the Popliteal Fossa: Always Visible, Never Seen. Eur J Vasc Endovasc Surg 2005;30:659-663 5 Tellings SS, Ceulen PPM, Sommer A. Surgery and endovenous techniques for the treatment of small saphenous varicose veins: a review of the literature, Phlebology 2011;26:179-184 6 Myers K. Surgery for small saphenous reflux is obsolete! Venous Digest 2005, modified from the ANZ J Phlebology
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Prevention of venous
thromboembolism: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy Author: Geerts WH, Bergqvist D, Pineo GF, Heit JA, et al. Chest. 2004;126(suppl):338S-400S. Contributing Editor/Reviewer: Amjad T. AlMahameed, MD, MPH Associate Editor: Stephanie Dentoni, MD
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COMMENTARY The 9th American College of Chest Physicians (ACCP) guidelines for prevention of venous thromboembolic disease (VTE) noted a major shift in the methodology used by the authors. They discarded surrogate endpoints (asymptomatic venographically-evident VTE) and elevated death and symptomatic VTE as the only reliable outcome measures. They also advocate incorporating bleeding risk alongside thrombotic risk assessment when deciding on pharmacoprophylaxis. Lastly, they recommend against the application of performance measures in medical patients that promote universal VTE prophylaxis regardless of risk. In the present viewpoint, I also review the events that led to mandating performance measures that, despite best intensions, may have promoted unforeseen risks. While I disagree with discarding a large body of evidence that links asymptomatic VTE to clinically relevant major adverse events, including death, I agree with the final
(VTE) remains... the most common cause of preventable hospital death, and a primary contributor to 10% of all hospital deaths.
recommendations to use thromboprophylaxis based on individualized risk-benefit assessment.
INTRODUCTION Venous thromboembolic disease (VTE) remains a major cause of morbidity and mortality, the most common cause of preventable hospital death, and a primary contributor to 10% of all hospital deaths.1,2 Overall, VTE may affect 10-40% of “at-risk” hospitalized patients who do not receive proper thromboprophylaxis.1,3 In fact, the thrombotic risk extends well beyond discharge from the index hospitalization in both surgical and non-surgical patients. In one population-based retrospective study, the average annual age- and sex-adjusted incidence of in-hospital VTE was more than 100 times greater than the incidence among community residents.4
1 Geerts WH, Pineo GF, Heit JA, et al. Prevention of venous thromboembolism: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest. 2004;126(suppl):338S-400S. 2 Sandler DA, Martin JF. Autopsy proven pulmonary embolism in hospital patients: are we detecting enough deep vein thrombosis? J R Soc Med. 1989;82(4):203–205. 3 Hillen HF. Thrombosis in cancer patients. Ann Oncol. 2000;11(suppl 3):273-276. 4 Heit JA, Melton LJ 3rd, Lohse CM. Incidence of venous thromboembolism in hospitalized patients vs community residents. Mayo Clin Proc 2001;76:1102
How Did Thromboprophylaxis Become “Universal”? Several factors have led to adopting near universal thromboprophylaxis to hospitalized patients. These include the markedly increased VTE prevalence in this at-risk group, serious adverse consequences of VTE (death, pulmonary embolism [PE], chronic post-thrombotic pulmonary hypertension and post-phlebetic syndrome) and the proven efficacy, safety and cost-effectiveness of thromboprophylaxis. Other important factors that fostered the generalization of these universal thromboprophylaxis recommendations include: 1) Absence of discrete prodromal phase: most VTEs noted in thromboprophylactic trials are subclinical (asymptomatic). Even in patients that were eventually labeled as having had symptomatic VTE, their initial signs and symptoms are common in this population and non-specific. 2) Absence of reliable screening test: venography, the gold standard used in thromboprophylactic trials, is highly accurate. Nonetheless, it is an impractical, invasive, expensive, and potentially thrombogenic test. Venous duplex ultrasonography is expensive and not all that sensitive in a large portion of hospitalized patients.
The past 10 years witnessed the introduction of a series of VTE prevention initiatives. Among these, several stand out as landmark documents: In 2006, The Joint Commission/National Quality Forum 17 performance measures (which was revised in 2008 to include 6 additional measures) were published.5,6 In 2008, The ACCP evidence-based clinical practice guidelines on antithrombotic and thrombolytic therapy included an expanded section on VTE prevention. It strongly emphasized that hospitals should consider developing strategies to consistently identify hospitalized patients at risk for VTE and actively seek to prevent VTE occurrence and recurrence.7 Soon thereafter, the US Surgeon General released a “Call to Action to Prevent Deep Vein Thrombosis and Pulmonary Embolism” that urged a coordinated, multifaceted plan to reduce the VTE incidence nationwide.8 The Agency for Healthcare Research and Quality (AHRQ) contributed to the “Call to Action” with the release of two new guides: one for patients and another for health care providers, counseling both to participate in disseminating VTE prevention recommendations.9
These successive initiatives, along with well-publicized campaigns that followed, led to the rapid dissemination of these recommendations. Quickly, hospital administration became engaged and decided to support VTE prevention programs. As front-line clinicians embraced the recommendations, VTE prophylaxis practices became “standard of care” and 5 http://www.qualityforum.org/Publications/2006/12/National_Voluntary_Consensus_Standards_for_Prevention_and_Care_of_Venous_ Thromboembolism__Policy,_Preferred_Practices,_and_Initial_Performance_Measures.aspx 6 http://www.qualityforum.org/Publications/2008/10/National_Voluntary_Consensus_Standards_for_Prevention_and_Care_of_Venous_ Thromboembolism__Additional_Performance_Measures.aspx 7 Geerts WH, Bergqvist D, Pineo GF, et al., American College of Chest Physicians. Prevention of venous thromboembolism: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest 2008; 133:381S–453S. 8 http://www.surgeongeneral.gov/library/calls/deepvein/index.html 9 http://www.ahrq.gov/professionals/quality-patient-safety/patient-safety-resources/resources/vtguide/vtguide.pdf
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“clinical practice pathways”; while “computerized electronic alerts” as well as “algorithm-based” strategies were widely developed to ensure continued compliance.
Another important, yet unspoken, factor that may have augmented this response was the federal government’s Centers for Medicare and Medicaid Services (CMS) threat to deny reimbursement for hospital-acquired VTE as it considered it a “preventable medical error”. Compliance with these guidelines (which the CMS presumed would eliminate such “preventable medical errors”) was therefore viewed as an important means towards improving patients’ outcomes, decreasing “preventable medical errors” and avoiding potential penalties. Such eagerness for “perfect compliance” was fostered and patrolled by hospital administrators and quality control medical officers. One wonders if this could have led to a speedy generalization of the recommendations to include some patients that may have been at extraordinarily low risk for VTE or unusually high risk for bleeding complications. Therefore, the “Sentinel Event Alert” released by The Joint Commission entitled “Preventing Errors Relating to Commonly Used Anticoagulants”) in late 2008 came as no surprise to us.
Reconciling the Newly Adopted ACCP Outcome Measures with Daily Practice The ACCP methodologists attempted to weigh the evidence for and against thromboprophylaxis using prevention of fatal PE and “symptomatic” VTE (which they presumed to be synonymous with “clinically relevant” VTE) as the primary goal of this treatment, while at the same time integrating serious bleeding complications into the final outcome. Interestingly, in order to justify this “new” endpoint, they considered asymptomatic, venographically-confirmed VTE to be clinically irrelevant and, therefore, could be discounted from the evidence. Needless to say, the arguments against using the disputed terms symptomatic/clinically relevant and asymptomatic/clinically irrelevant interchangeably are obvious to every practicing clinician and well summarized in the paper by Bounameaux and Agnelli.
In my opinion, the advantages of advancing the discussion about VTE prophylaxis practices as universal recommendation are many. It certainly highlights the importance of thoughtfully considering the risks and benefits of pharmacoprophylaxis in every hospitalized patient and removing the automation from the process. The limitations inherent in the historical studies used by the authors as basis for their recommendation (whether supporting “symptomatic” or disputing “asymptomatic” events) call for expanding funding for larger, well conducted prospective studies that address these issues directly. Further research focused on improving clinically-accepted means of enhanced profiling of thrombotic as well as bleeding risks in profiling of hospitalized patients are also needed.
Conclusions Clinical guidelines are meant to raise awareness and highlight the public health impact as well as establish a framework for approaching a specific clinical problem. Clinical judgment and individualized risk assessment remain the most critical component of decision making, and this is particularly true when it comes to VTE prophylaxis.