MAIN DISORDERS BY SYSTEM
33
CARDIORESPIRATORY SYSTEM
27 Interventional techniques
and devices
Minimally invasive surgery or interventional procedures have been developed in recent years to improve recovery time, mortality, and analgesia in complicated surgical procedures and those involving difficult-to-access anatomical areas. Thanks to technological advances, veterinary surgeons can use devices to cure diseases that were previously untreatable. Some of these devices are described below.
Endoscopes Very thin optical devices covered with a rigid or flexible sheath. These are introduced via narrow channels and used to visualise specific structures, which can then be operated on (cut, extracted, sutured, cauterised, etc.).
Endoprosthesis (stent)
Drainage catheters
Tubular dilators that are permanently or temporarily placed in deformed or narrowed ducts and allow the passage of air (tracheal or nasopharyngeal stent), urine (ureteral and urethral stent), or blood.
Made of very soft, non-harmful materials, these allow permanent drainage of fluids from the chest, abdomen, or renal pelvis (subcutaneous ureteral bypass, SUB).
Intravascular devices These are introduced into the blood vessels with radiological guidance and help to plug vascular malformations. Currently two types are used: embolisation coils and Amplatzer devices.
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Balloon catheters These are introduced into narrowed blood vessels, malformed heart valves, or naturally narrow ducts (e.g. urethra, nasopharynx, or oesophagus) and are inflated under high pressure to dilate the narrowed lumen.
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PET OWNER EDUCATIONAL ATLAS. DOGS
DIGESTIVE SYSTEM AND ABDOMINAL CAVITY
56 Nutrition and related
digestive diseases
Dog are non-strict carnivores, capable of obtaining energy and metabolic resources from animal and plant nutrients. In addition, they can digest a small amount of starch (carbohydrates).
Standard diet ■
■
4
The standard diet of a healthy adult dog should consist of the following groups of nutrients: 1. Proteins and amino acids: 20–30 % of metabolisable energy (ME). 2. Fats and essential fatty acids: 25–35 % of ME. 3. Fibre and carbohydrates: 15–30 % of ME. 4. Vitamins and minerals: vitamins D, E, and K, zinc, phosphorus, calcium, and magnesium. Most owners choose commercial diets formulated by specialists. If it is decided to provide homemade or raw food, care must be taken to balance the nutrients and avoid infections by bacteria and protozoa.
3
Food intolerance ■
■
This happens when a dog eats a meal, sometimes for the first time, and responds with acute vomiting and/ or diarrhoea. The causes can be metabolic (excess histamine or lactose in food) or microbial (presence of toxins or bacteria).
2
Food allergy ■
■
■
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1
Immune disease caused by sensitisation to some protein in the diet. The clinical signs develop progressively as the dog repeatedly ingests the food. Initially these signs are exclusively digestive, but little by little the skin is affected with generalised itching and skin lesions of varying severity. This protein should be eliminated from the diet or commercial foods containing hydrolysed proteins should be administered.
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MAIN DISORDERS BY SYSTEM
HEMATOPOIETIC SYSTEM AND ONCOLOGY
67 Canine lymphoma This is a malignant tumour that is caused by the proliferation of lymphoid cells and affects lymph nodes and some solid organs (spleen, liver, intestine).
Presentation ■
■
■
Tumour presentation varies depending on the location of the affected organs. The most common form is multicentric (i.e. growth of different nodes throughout the body). The next most frequent presentations are the alimentary (digestive system), mediastinal (cardiorespiratory system), and cutaneous forms. Submandibular lymph node
Certain breeds are predisposed to this tumour type (e.g. Boxer, Bulldog, Golden Retriever, Mastiff), especially those aged 6–9 years.
Spleen
Prescapular lymph node
Intestines
Popliteal lymph node
Axillary lymph node
Liver Superficial inguinal lymph node
Tumour cells obtained by biopsy
Diagnosis ■ ■
■
Biopsy is key to reveal the presence of tumour cells. Blood and imaging tests can help the veterinary surgeon determine the extent and severity of the disease. Lymphoma should be classified according to the predominant cell type in order to determine the prognosis and most appropriate treatment.
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Treatment ■
■
Treatment is effective in 90 % of dogs in the short term, but the prognosis depends on the type of cells involved (T or B cells) and the extent at the moment of diagnosis. Fortunately, there are many effective drug protocols for this disease.
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MAIN DISORDERS BY SYSTEM
HEMATOPOIETIC SYSTEM AND ONCOLOGY
69 Canine haemangiosarcoma This is a malignant tumour that affects the inner walls of the blood vessels. It appears to originate from the erroneous differentiation of endothelial cells in the bone marrow. These malignant cells travel through the vessels, in which tumour masses then form.
Clinical presentation ■
■
■
■
The most common locations of the primary tumour are the spleen, heart, skin, and liver. This tumour exhibits extremely aggressive biological behaviour, with frequent metastases in the liver, abdominal cavity, lungs, and even the brain. Most frequent clinical signs: sudden weakness, pale mucous membranes, and even shock. These are all caused by rupture of the tumour and internal bleeding. When the skin is affected, the resulting lesions are usually nodules that bleed easily.
The breeds in which this tumour is most frequently diagnosed include German Shepherd, Labrador Retriever, and large breeds in general.
Diagnosis ■
Early diagnosis by ultrasound or computed tomography and collection of biopsy samples can be key to achieving cure.
Brain Lungs Skin
Spleen
Endothelial precursor cells
Abdominal cavity Heart Malignant endothelial cells (origin, bone marrow)
Liver
Primary tumours Most frequent metastases
Treatment The most effective treatment is surgery to remove the main mass followed by a chemotherapy protocol.
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