Slide Collection (Companion Animal Clinical Studies - Critical Care)

Permanent URI for this collectionhttp://hdl.handle.net/2263/11080

Slide collection of Dr Mirinda van Schoor, senior lecturer / veterinary specialist physician at the University of Pretoria, Faculty of Veterinary Science, Dept. of Companion Animal Clinical Studies. She has a special interest in critical care medicine and is involved in pre- and postgraduate student training and research. Dr van Schoor assigned the metadata for this collection

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For inquiries regarding this collection or items in the collection, please contact Myleen Oosthuizen Tel.: +27 12 529 8007

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Discoid lupus erythematosous
(2010-11-05T09:22:28Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-2: DLE (discoid lupus erythematosous) is a common skin condition in dogs. It causes nasal depigmentation, erythema, scaling, erosions, ulcerations and crusting. The lesions may involve the lips, bridge of the nose, periocular skin, ear pinnae, distal limbs and genitalia. Diagnosis is via dermatohistopathology and immunofluorescence of skin biopsy specimens. Treatment includes the use of symptomatic shampoos to remove crusts, avoiding exposure to sunlight or sunscreens, topical glucocorticoids, tetracycline and systemic therapy with vitamin E supplementation.
Popliteal lymph node biopsy
(2010-11-05T09:21:44Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTO 1: The popliteal lymph node is a palpable lymph node that is situated in the popliteal area of the hind limb. Prior to a lymph node biopsy the skin overlying the lymph node must be prepared by shaving the hair and sterilizing the surgical site. PHOTO 2: Surgical instruments that are required for a biopsy include forceps, dissecting scissors, a surgical blade and biopsy needles. PHOTOS 3-8: The popliteal lymph node is a palpable lymph node that is situated in the popliteal area of the hind limb. Before a biopsy the lymph node must be palpated to evaluate the consistency of the lymph nodes. A small incision in the skin covering the lymph node facilitates the passage of the biopsy needle. The biopsy needle is then advanced though the lymph node. The needle is then withdrawn from the body with the biopsy sample. The biopsy sample can then be transferred to a biopsy cassette.
Papules
(2010-11-05T08:21:59Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-2: Skin papules are primary lesions. Papules are small, solid elevations in the skin that can be palpated as a solid mass and grow up to 1cm in diameter. Papules may be pink or red swellings caused by tissue infiltration of inflammatory cells. Hair follicles may or may not be involved. Erythematous papules are seen in scabies and flea bite hypersensitivity. Superficial bacterial folliculitis may also produce papules in the dog.
Porcupine attack
(2010-11-05T08:21:09Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-5: Porcupines attack when threatened by facing away from the aggressor with erect quills. The quills detach on contact. Problems caused by porcupine attacks include pain, local tissue irritation and trauma, infection of tissues deep to the skin, quill migration into joints or vital organs and complications associated with penetration of thorax or abdomen. Dogs that have been attacked by porcupines usually have multiple quills embedded in the mouth and other areas of the head. The quills may also enter the eye and orbit. Porcupine quills may harbour bacteria that could evoke a septic or sterile foreign body reaction. The point of the quill is sharp and there are multiple barbs arranged around the point, promoting migration of the quill. The retrograde barbs on porcupine quills allow them to migrate up to 10 inches under the skin. Quills have been known to migrate to the eye and orbit, brain and vertebral column of dogs. Quill migration is associated with cutaneous draining tracts and sudden death. Infections with Staphylococcus spp. often occurs as these bacteria are present on the porcupine quills. These infections may lead to septic arthritis. The veterinarian may be unable to remove quills due to widespread distribution, depth of penetration, complete or partial removal prior to presentation, breakage, thick hair coat or obesity. To avoid injury and migration due to missed quills it is essential to do a complete physical examination with thorough oral examination. Dogs that have been attacked by porcupines need to be treated as soon as possible because the longer the quills remain in a dog, the more time they have to migrate deeper into tissues. Quills also become less rigid and more friable the longer they remain in tissue and this makes them more likely to break during removal.
Cages for hospitalized patients and intensive care unit cages
(2010-11-05T07:35:28Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-4: Hospitalized animals must be housed in cages that are secure and comfortable. There should be no sharp edges so the patient cannot hurt itself. The cage should be large enough so the animal can move and turn around. Many critically ill animals may have problems maintaining normal body temperature and need an external heat source. A heating mat can be placed on the floor of the cage so the animal is comfortably warm. Hospitalized animals can develop hyperthermia from heating pads and this should not be confused with true fever. Stainless steel cages should be used and should ideally be placed against the walls of the ward. The cage door must be able to close securely to prevent escape of the patient. Cages must be kept clean and cleaned and disinfected between patients. PHOTO 5: ICU cages should be comfortable and safe for the patient. There should be clear notices of the treatment and special needs of the patient on each cage. Monitoring of patients in the intensive care unit is critical. The cages may be placed on top of each other in rows and adequate space should be allowed for therapeutic and monitoring equipment. PHOTO 6: Oxygen cages are useful for controlling oxygen concentration, temperature and humidity and allow animals to ventilate without assistance. Inspired oxygen concentration of 30-40% is recommended for animals that need oxygen therapy. If the oxygen concentration is too high it can cause oxygen toxicity. Oxygen cages provide a sealed environment, where the fraction of inspired oxygen, humidity and ambient temperature can be controlled and monitored and carbon dioxide can be removed efficiently. Oxygen cages with a Plexiglas front allow observation of the patient, these oxygen cages also have access ports for entry and exit of intravenous lines and monitoring leads. The advantage of using oxygen cages is that it is a non-invasive way of providing oxygen support to critically ill patients. A disadvantage is that oxygen is lost each time the door of the cage is opened. The amount of oxygen lost each time the door is opened and the amount of oxygen needed to fill the cage makes the use of oxygen cages relatively wasteful and expensive.
Abdominal hernia
(2010-11-05T07:19:40Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-5: External abdominal hernias are defects in the abdominal wall allowing protrusion of the abdominal contents. External abdominal hernias involve any part of the abdominal wall other than the umbilicus, inguinal ring, femoral canal and scrotum. True hernias are those where the contents are enclosed in a peritoneal sac while false hernias are not surrounded by a peritoneal sac. Abdominal hernias are false hernias. Abdominal hernias occur secondary to trauma such as vehicle accidents or bite wounds but may also be congenital or iatrogenic. Abdominal hernias are defined according to their location as ventral, prepubic, subcostal, hypochondral, paracostal or lateral abdominal hernias. Abdominal hernias are painful and the animal may become anorexic. The swelling should be palpated to determine the contents of the hernia and to locate the abdominal defect. Abdominal radiographs may be made to confirm whether it is a hernia if the abdominal wall defect cannot be palpated due to swelling or pain. The initial treatment for abdominal hernias includes treating shock and internal injuries. The abdominal hernia can then be repaired by apposing the disrupted abdominal wall edge to the pubis, ribs or fascia or by suturing the torn muscle edges.
Bone biopsy
(2010-11-05T07:18:11Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-2: Bone biopsies and histopathological evaluation are the only ways to establish a definite diagnosis of a bone tumour. Bone biopsies are also used to evaluate bone tissue abnormalities characteristic of certain diseases and to evaluate the effects of therapeutic regimes on bone. Bone biopsies have the disadvantages that they are invasive and that there is a question of how representative the specimen is of the whole bone tissue. These disadvantages can be overcome by careful surgical procedure in which the muscle is cut as little as possible, working aseptically and controlling infection and bleeding with antibiotics and packing. Closed biopsy techniques are preferred for bone biopsies because they have a lower complication rate and are less expensive. Bone can be biopsied with a trephine instrument or a jamshidi biopsy needle. The biopsy needle is a small bone trephine instrument without cutting serrations on the tip. PHOTOS 3-6: The site of bone biopsy is usually at the junction of lytic and normal bone and another biopsy is done in the centre of the lytic area. Multiple biopsies can be done without weakening the bone if only one cortex is penetrated. The rib and iliac crest are often used for bone biopsies. The rib is not the best site as it could cause a fracture. The iliac crest is mostly used as biopsy in this area does not result in fracture, the proportion of trabecular to cortical bone is similar to that of the whole skeleton and the procedure is almost painless. PHOTOS 7-16: The lesion is located radiographically and the area to be biopsied is determined. The animal is placed under general anaesthesia. The skin over the biopsy site is clipped and the surgery site is prepared with a surgical scrub. The region is draped and an incision is made. Blunt dissection is used to reach the bone to be biopsied. The biopsy needle is inserted with its stylet in position through the incision and advanced through the overlying muscles to the bone. The stylet is removed once bone contact has been made. The instrument is rotated back and forth along its longitudinal axis to reach the required depth in the bone. The entire medullary cavity of the bone should be crossed. Once the desired depth is reached the instrument is rotated 360º in one direction several times. It is then rocked back and forth several times to break off the core. The end of the shaft is covered with the thumb to create a vacuum to hold the sample in and the instrument is gently removed. The sample is cleared from the shaft with a stylet. If using a jamshidi needle the shaft of the needle is cleared retrograde. Suture the skin as necessary. A light wrap can be applied to decrease the chances of haematoma formation. Post operative radiographs are made to confirm the location the biopsy sample was taken from. PHOTOS 17-18: The bone sample is transferred to a biopsy cassette for histopathology and measurement of the sample.
Critical care drugs
(2010-11-05T07:17:19Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-3: Ampoules are small, hermetically sealed glass or plastic containers which may contain medication for parenteral administration or semen for insemination. Pramalon and Ondansetron are antiemetics that are available in ampoules. PHOTO 4: A suspension is a preparation of undissolved substance in a liquid vehicle. Lacson syrup is an oral suspension used for the relief of constipation. PHOTO 5: Sodium bicarbonate is used as a gastric antacid and a systemic and urinary alkalinizer. It can also be used locally to remove mucus, exudates and scabs. Sodium bicarbonate is used for the alkalinization of urine in carnivores as it increases the elimination rate of long acting barbiturates. Administration of sodium bicarbonate to animals with lactic acidosis may improve tissue perfusion but risks causing overshoot metabolic alkalosis. PHOTO 6: LAXETTE [Medpro Pharmaceutica (Pty)Ltd] is a sweet-tasting, colourless to yellow-brown solution that is presented in 150mL and 500mL amber glass bottles or 2,5L amber or white plastic containers. 5mL of LAXETTE contain 3,3g lactulose. Lactulose is an osmotic cathartic that is normally used to prevent and treat hepatic encephalopathy in dogs, cats and birds by reducing blood ammonia concentration. It can also be used to treat chronic constipation in dogs, cats and reptiles. It is a synthetic derivative of lactose and cannot be digested by enzymes of the mammalian and probably not by the avian digestive tract. Upon reaching the colon, lactulose is metabolized by the gut bacteria forming organic acids and CO2.These acids cause a laxative effect by increasing osmotic pressure and drawing water into the intestinal lumen. Furthermore, it causes acidification of the colon content that in turn cause ammonia to migrate from the blood to the colon where it is excreted with the faeces. Adverse effects of the drug include flatulence, gastric distension, cramping and diarrhoea. This drug must be used cautiously in patients with pre-existing fluid and electrolyte imbalances and water should be made freely available to patients treated with this drug. Cats dislike the taste of lactulose making administration difficult. The drug is not readily absorbed by the gastrointestinal tract and most of it is excreted unchanged in the urine within 24 hours. Lactulose may also be known by the synonym lactulosum. PHOTO 7: Atropine (0.5 mg/mL and 10 mg/mL, Centaur) is a muscarinic receptor antagonist. Muscarinic receptor antagonists block the binding of acetylcholine to muscarinic receptor cholinergic receptors on smooth and cardiac muscle, gland cells, peripheral ganglia and the central nervous system. Atropine is a naturally occurring substance that can be found in the plants Atropa belladonna (deadly nightshade) and Datura stramonium (jimsonweed). It generally causes relaxation of bronchial, biliary and urinary tract smooth muscle but also has excitatory effects on the central nervous system. Effects of the substance are dose dependant. Small doses of atropine inhibit salivary and bronchial secretion and sweating. Increased doses cause pupils to dilate and blocks vagal effects to the heart leading thereby to increased heart rate. Larger doses inhibit micturition and decrease tone and motility of the gut and may even completely inhibit gastric motility and secretion. Atropine is often used as an addition to anaesthesia to increase heart rate and decrease respiratory and gastro-intestinal secretions. It can also be used as an antidote for organophosphate poisoning. Atropine should not be used in patients with glaucoma, intestinal ileus, gastroparesis or tachycardia. Certain species like the rabbit have an enzyme, atropine esterase, which allows these animals to rapidly metabolize the drug. PHOTO 8: SYNULOX® RTU is a schedule 4 broad spectrum antibiotic [Pfizer Laboratories (Pty)Ltd]. In vitro it is active against a wide range of clinically important gram-positive and gram-negative bacteria and it has been clinically shown to be effective in treating a wide range of disease conditions of cattle and small mammals. SYNULOX® RTU injection contains 35mg/mL clavulanic acid and 140mg/mL amoxicillin. Clavulanic acid is naturally produced by Streptomyces clavuligerus and competitively and irreversibly binds to beta-lactamases and penicillinases. Amoxicillin is penicillin that inhibits mucopeptide synthesis in the cell wall resulting in a defective barrier. After shaking the vial to suspend the active ingredients, it can be injected by the subcutaneous or intramuscular route. Clavulanic acid is moisture sensitive, so dry syringes must be used for injection. It is contra-indicated in known cases of hypersensitivity to penicillins and other related compounds and should not be used in rabbits, guinea pigs, hamsters or gerbils. SYNULOX® RTU injection is a smooth, off-white to pale buff coloured fluid presented in 50mL or 100mL clear glass vials. PHOTOS 9-11: The active ingredient found in Flagyl® Suspension (Aventis Pharmaceuticals) is metronidazole, an antibacterial and antiprotozoal agent. It is active against most obligate anaerobes and can be used to treat both enteric and systemic anaerobic infections. It does however, have no effect on aerobic bacteria. Metronidazole has been used extensively by veterinarians in the treatment of Giardia in dogs and cats. In addition, metronidazole has therapeutic activity against Entamoeba histolytica, Trichomonas and Balantidium coli. This drug is also effective against anaerobic osteomyelitis and can be used as preventive treatment for lower gastro-intestinal surgery. Although adverse effects of the drug are uncommon, vomiting, nausea and inappetence may occur. Cats often salivate profusely after administration. Metronidazole is also a potential teratogen and should therefore not be used during pregnancy, especially during early pregnancy, unless the benefits outweigh the potential risks to the foetus. This drug must be used with caution in animals with hepatic dysfunction. PHOTO 12: Intravenous administration of antibiotics may be necessary when a patient becomes critically ill or when an infection becomes life-threatening. PHOTO 13: Ulsanic suspension is used to relieve and prevent gastritis, reflux, oesophagitis and peptic ulcers in humans. Each 5ml contains 1g sucralfate, a compound used to prevent and treat gastric and intestinal ulceration and gastritis in animals. It is also commonly used by veterinarians to treat non-steroidal anti-inflammatory drug (NSAID) induced ulcers. Ulsanic suspension must be stored in a cool (below 25°C), dry place. PHOTO 14: The active ingredient found in Kortico is dexamethasone. Dexamethasone is a synthetic adrenal steroid with glucocorticoid activity and little mineralcorticoid activity. Dexamethasone can be used to induce parturition in many domestic species by administering it intramuscularly or subcutaneously during late gestation. Dexamethasone mimics the foetal cortisol and action on the placenta in the same fashion. Adverse effects are associated with long-term administration and are generally manifested as symptoms of hyperadrenocorticism. It can also retard growth in young, growing animals. PHOTO 15: Ropivicaine is a long acting local anaesthetic with a high efficacy and potency but lower central nervous system and cardiovascular system toxicity than other local anaesthetics. Ropivicaine is vasoconstrictive if injected at low concentrations and has vasodilating effects at higher concentrations.
Granulomatous meningoencephalitis
(2010-11-05T06:50:13Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
Granulomatous meningoencephalitis (GME) is an idiopathic inflammatory disease of the central nervous system of dogs and less commonly of cats. It is likely that GME is an autoimmune disease, although infectious and neoplastic causes have also been suggested. Three morphological forms of the disease have been described : an ocular form, a focal form and a diffuse (or disseminated) form. Cerebral spinal fluid may present pleocytosis of monocytes and lymphocytes, as well as mild protein elevation. Brain imaging may reveal multifocal lesions predominantly in the white matter of the central nervous system with the focal form of the disease, while brain parenchyma normally has a heterogeneous appearance in the diffuse form. GME is normally treated with corticosteroid immunosuppressive therapy with additional radiation therapy recommended for the focal form of the disease. Cyclosporine has also been successfully used to treat GME in some dogs. Prognosis of GME is generally poor, with survival times ranging from weeks to years.
Steroid responsive meningoencephalitis
(2010-11-05T06:47:49Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-2: Steroid responsive meningitis-arteritis (SRMA) is an immune mediated, inflammatory disease of the meninges and associated vasculature that is commonly documented in dogs. SRMA can occur in any breed of dog although some breeds like beagles, boxers, Bernese mountain dogs, Weimeraners and Nova Scotia duck tolling retrievers are more likely to be affected. Affected dogs may be seen to stand with an arched spine and be reluctant to walk as a result of pain. Furthermore, the dog may refuse to eat or drink unless the bowl is raised to head level. Two clinical forms of steroid responsive meningitis-arteritis are presented : a classical acute form and a less common chronic form. Typical symptoms of the acute form include hyperesthesia along the vertebral column, cervical rigidity, a stiff, hunched gait and fever. High immunoglobulin A concentrations in both serum and cerebral spinal fluid are typically found in affected dogs, and may aid in diagnosis. Polymorphonuclear pleocytosis, elevated protein and variable red blood cells are present in the cerebral spinal fluid (CSF). In severe cases, banded or segmented neutrophils may be observed in the CSF. Bacterial cultures will be negative and cervical vertebrate radiographs normally ruling out bacterial meningitis and damage to the cervical vertebrae. Dogs with acute SRMA that are treated with early anti-inflammatory and/or immunosuppressive therapy (Prednisone) generally recover well. Cerebral spinal fluid should be normal before discontinuing prednisone therapy. Additional immunosuppressive therapy like mycophenolate, azathioprine or cyclosporine may be required for the chronic form.
Bone marrow aspiration
(2010-11-05T06:44:59Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-2: The bone marrow biopsy needle is used to perform biopsies of bone marrow but not the bone. It has a large handle facilitating introduction of the needle into bone and a stylet to prevent tissue coring. PHOTOS 3-4: Bone marrow aspiration biopsy provides information on the condition and activity of the haemopoietic cells in bone marrow. Bone marrow aspiration biopsy is indicated in cases where there is obvious or suggested dysfunctioning of the haemopoietic system but there is insufficient change in peripheral blood to make a diagnosis. Conditions where a bone marrow evaluation is necessary include non regenerative anaemia, pancytopenia, neutropenia, thrombocytopenia, proliferative abnormalities, suspected malignancies and cell maturation problems. Bone marrow aspiration can be done with only light restraint and local anaesthetic. Bone marrow aspiration is a relatively safe procedure with very few contraindications. Bone marrow samples are used for the study of cell markers, cytogenetic study, ultrastructural examination, culture for microorganisms and to culture haemopoietic precursors for the preparation of histological sections. Bone marrow aspirates are the best samples for cytological examination. Bone marrow aspiration is especially useful for investigating suspected aplastic or hypoplastic anaemia, lymphoma, metastatic carcinoma and diseases of bone. The sites that are most commonly used for bone marrow aspiration in small animals are the head of the humerus and the wing of the ilium. It can be done with only light restraint and local anaesthetics. The skin directly over the selected site is clipped and cleaned with a surgical scrub. The area is anaesthetized using a local anaesthetic. An incision just large enough for the bone marrow aspiration needle to pass through is made. The needle is inserted and rotated into the bone. When the needle feels firmly inserted into the bone, the stylet is withdrawn and a plastic syringe is attached to the needle hub. Negative pressure is applied until a few drops of red bone marrow appear in the tip of the syringe. The syringe is removed and the stylet replaced, the needle is then repositioned for another aspiration attempt. The needle is withdrawn from the patient. Cytology smears are made right away to avoid clotting, the slides can be air dried and stained with any Romanowsky stain. Bone marrow samples can also be obtained via open biopsy under general anaesthetic. Complications of bone marrow aspiration are rare but cardiac and great vessel laceration may occur. Haemorrhage is uncommon but prolonged firm pressure may be necessary after the procedure to ensure bleeding stops in patients with bleeding disorders. Biopsy needles may break in patients that have osteosclerosis.
Neoplasia of the skin
(2010-11-05T06:42:39Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-5: Neoplasia of the skin and subcutaneous tissues are the most common tumours affecting dogs and there are several different types of neoplasia found in skin. Skin tumours are usually classified histologically as there are so many cutaneous structures that could be involved. Tumours are classified according to the tissue of origin and the level of malignancy. Mast cell tumours are the most common type of cutaneous tumour found in dogs. Schnauzers, Boston terriers and Labrador retrievers are some of the breeds that are predisposed to mast cell tumours. Cutaneous mast cell tumours arise from mast cells in the dermis and subcutaneous tissues. These tumours are often infiltrative and metastasize easily to bone marrow and other organs. Undifferentiated mast cell tumours are big, rapidly growing, ulcerated lesions. Hair loss and erythema are common. Mast cell tumours are diagnosed via fine needle aspiration cytology. Rowmanovsky and rapid haematologic type stains are used. Treatment is via surgical excision, radiation therapy or external beam radiotherapy. Poorly differentiated, metastatic mast cell tumours are fatal if there is not effective post surgical treatment. PHOTO 6: Eyelid neoplasms are common in older dogs and are usually benign. Eyelid masses can be resected but the eyelid structure must be restored after excision to maintain long-term ocular surface health. If the structure of the eyelid is damaged it may cause corneal exposure, irritation and ulceration. The most common eyelid neoplasms are sebaceous gland tumours, papillomas and melanomas. Papillomas are more common in younger dogs. Ocular papillomas may have papovavirus aetiology. Eyelid masses that are rapidly growing and ulcerated or are associated with corneal irritation should be resected as soon as possible. Histologically malignant eyelid tumours rarely metastasize and most eyelid tumours are histologically benign. Prognosis for most eyelid tumours is good as metastasis is rare and recurrence rates are low.
Oxygen therapy
(2010-11-05T06:40:58Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-5: Many critical illnesses can cause hypoxia to occur and oxygen supplementation may be necessary to improve oxygen delivery and to prevent lactic acidosis. A nasal cannula is the best way to supplement oxygen in conscious patients. Oxygen supplementation is an important management tool for critical conditions such as cardiopulmonary disease, sepsis, SIRS and head trauma. Nasal cannulas are easy to place, require minimal equipment and are well tolerated by patients. To place a nasal cannula, the patient's nasal passage is anaesthetized and the correct length of tube is measured from the nostril to the medial canthus of the eye. The lubricated tube is gently inserted into the ventral nasal meatus and is secured adjacent to the nostril with suture or staples. Sneezing and intolerance can be alleviated by reapplying the topical anaesthetic or pushing the nasal cannula into the nasopharyngeal region. An Elizabethan collar can be used to prevent the patient from dislodging the nasal cannula. A nasal cannula allows for prolonged oxygen delivery and permits access to the patient for examination and treatment purposes without losing the oxygen rich environment. A disadvantage of using a nasal cannula is that the fraction of inspired oxygen cannot always be determined accurately. The necessary oxygen flow rate is based on patient size, respiratory rate, respiratory pattern and the degree of open-mouth breathing. If a unilateral nasal cannula is used it should be replaced with a new cannula on the opposite side every 48 hours so as to reduce damage to the airway. Most animals tolerate the cannula well.
Emergency clinical examination
(2010-11-05T06:39:44Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTO 1: In an emergency clinical examination the first priority is to focus on the efficacy of oxygen delivery and assess the respiratory and cardiac systems. The airway must be cleared of any obstructions and artificial respiration applied if necessary. The respiratory and cardiovascular systems are examined by auscultation of the heart and lungs, palpation of venous distension and arterial pulse and evaluation of mucous membrane colour and capillary refill time. The heart rate and the strength of the pulse are important to take into account. The patient’s level of consciousness should be frequently assessed as a sign of neurologic and metabolic status. Temperature and hydration status should also be assessed. PHOTO 2: When several patients are presented simultaneously after being poisoned, the clinician needs to prioritize patient care. The process of sorting or prioritizing patient care when there are multiple patients requiring care is called triage. When a group of patients require emergency care, those that are not ambulatory are given the highest priority, with those that can walk by themselves but have breathing or circulatory problems receiving the second highest priority. Patients requiring triage include those arriving in emergency situations, patients being transferred to ICU and current ICU patients that deteriorate suddenly. Rapid assessment and triage should be completed as soon as possible after arrival of critically ill or injured animals. A quick assessment of history should be done. The ABCD approach is used in the primary survey of critical patients : airway, breathing, circulation and disability. A secondary survey is done once emergency therapy has been started. This includes a full physical examination and measurement of arterial blood pressure. PHOTO 3: Gastric lavage is the use of an orogastric tube for the administration or removal of small volumes of liquid and to remove toxic substances from the stomach. It is done when emesis has failed or is contraindicated or in cases where charcoal must be administered immediately. Gastric lavage is contraindicated when hydrocarbons or corrosive substances have been ingested. Gastric lavage is most effective within one to two hours after ingestion of the toxic substance. If the animal is conscious, gastric lavage is done under general anaesthesia and the patient is intubated to prevent aspiration. The patient is positioned in lateral recumbency with the thorax higher than the head. The right length of tube is measured from the tip of the nose to the last rib. The tube is gently placed down the oesophagus and correct placement is confirmed. Warm water or saline is infused into the tube to moderately extend the stomach and the fluid is then allowed to drain from the tube via gravity flow until clear fluid is returned. Activated charcoal may then be administered through the tube. PHOTO 4: Endotracheal intubation is the process of inserting a tube into the trachea. If the patient lacks adequate gag reflex due to neurologic disease, sedative administration or cardiopulmonary arrest, it requires immediate intubation to protect the airway. Endotracheal intubation provides a patent airway in patients with upper airway obstructions, protects against aspiration in patients without normal airway protection mechanisms and allows for the administration of oxygen, gaseous anaesthetics or positive pressure ventilation. Intubation is done by laryngeal visualization and inserting a cuffed endotracheal tube of the right size. Intubation is usually performed in a dog in sternal recumbency. Intubation may be difficult in dogs with upper airway obstruction or trauma. Preoxygenation is recommended before intubation of critical patients.
Epidurals
(2010-11-05T06:35:43Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
Epidurals can be used to administer analgesia to the caudal half of the body. Administration of analgesics into the epidural space provides decreased sensory and sympathetic pain. Opiods, phenocyclidines, α-agonists or non-steroidal anti-inflammatory drugs may be injected during epidural analgesia. Epidural anaesthesia is the injection of a local anaesthetic for complete motor blockade. Epidurals are used for caesarean sections, thoracostomy, pelvic or hind limb orthopaedic manipulations, amputations, abdominal procedures, tail or perineal procedures, diaphragmatic repair, pancreatitis, peritonitis and intervertebral disc disease (IVDD). Epidurals provide long lasting, quick onset of analgesia with few systemic side effects for medical surgical pain. It is also used as an alternative to general anaesthesia in animals that are high risk. Epidurals are performed at the lumbosacral junction as the spinal cord terminates cranial to this junction.
Blood sampling
(2010-11-05T06:32:28Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
Blood sampling can be done using a syringe and needle or a vacutainer kit. Blood collection is usually done from the jugular vein, but the cephalic vein may also be used. Blood sampling from the jugular can be done with the animal in a sitting position with its head twisted up to one side. The vein is raised by pressure, the needle is inserted into the vein and blood is withdrawn. When enough blood has been collected the pressure on the vein is released and the needle is withdrawn. Afterwards, pressure is applied to the punctured site.
Superficial pyoderma
(2010-11-05T06:30:26Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-2: Superficial pyoderma is a superficial bacterial infection of hair follicles and surrounding epidermis. It is usually secondary to an underlying cause such as allergies and endocrine diseases. Superficial pyoderma is characterized by focal to multifocal areas of papules, pustules, crusts, scales and epidermal collarettes. Circumscribed areas of erythema and alopecia with hyperpigmented centres may be present. Short coated dogs often have patchy alopecia giving a moth eaten appearance. In long coated dogs symptoms include a dull lustreless hair coat, scales and excessive shedding. Pruritis ranging from mild to severe may occur. The most common bacteria causing pyoderma in dogs is Staphylococcus intermedius. Treatment usually consists of systemic antibiotics and bathing with antibacterial shampoo containing chlorhexidine, ethyl lactate or benzoyl peroxide. The underlying cause should be identified and treated.
Osteosarcoma in dogs
(2010-11-05T06:27:51Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-2: Osteosarcoma is the most prevalent primary bone neoplasm in dogs. These neoplasms are mostly malignant and may cause death due to local infiltration or metastasis. They especially metastasize to the lungs in dogs. Osteosarcoma affects the appendicular or axial skeleton and occurs mostly in large and giant breed dogs. Some dogs are genetically predisposed to developing osteosarcomas. Appendicular osteosarcomas occur mostly in the metaphyses of the distal radius; femur or proximal humerus. Osteosarcomas are diagnosed radiographically and exhibit a lytic proliferative pattern in the affected bone. Pre-amputative diagnosis can be made by histopathological evaluation of bone biopsies. Amputation is the treatment of choice along with chemotherapy. If the owners of the animal understand the high risk of the animal dying of metastatic lung disease and if the clinical radiographic findings are suggestive of osteosarcoma, the limb can be amputated without histological diagnosis. An alternative to amputation is resecting the bone and using an allograft from a cadaver to replace the neoplastic bone. These animals are also treated with chemotherapy. The main complication of this limb sparing method is the development of osteomyelitis in the allograft which then makes amputation necessary.
Snake bite
(2010-11-05T06:26:53Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
Dogs are commonly bitten by snakes on the head and front legs. Factors affecting the toxicity of the snake bite include the victim’s size, pre-existing health, the site of the bite and the time between the bite and medical attention. The initial clinical signs of snakebite include local pain, swelling, petechiation, echymosis and discolouration of the skin in the area of the bite. The swelling may mask the bite wounds. Swelling of the head or front legs around the bite may cause regional circulatory changes which reduce venom uptake. Initial first aid in the case of snakebite should be to keep the patient quiet as exertion will speed the spread of the venom. The bite wound should be kept below heart level. Tracheostomy may be necessary in cases with severe head swelling as breathing may be compromised. Treatment of muscle tremors, seizures, cardiac arrhythmias and pulmonary oedema should be treated as the conditions manifest. Administration of anti-venom can reverse most symptoms of poisoning if it is available. The prognosis for snakebite depends on the type of snake involved, the severity of the envenomation and the rapidity of veterinary treatment.
Veterinary ICU equipment
(2010-11-05T06:26:09Z) University of Pretoria. Faculty of Veterinary Science. Dept. of Companion Animal Clinical Studies; Van Schoor, Mirinda
PHOTOS 1-3: A syringe driver is a type of infusion pump that are used in hospitals to administer small amounts of medication to a patients. PHOTOS 4-5: Infusion pumps are used in the ICU to administer fluid or medication directly into a patient’s circulatory system by means of a high but controlled pressure. The user simply enters the amount of fluid and the time the fluid needs to be delivered. PHOTO 6: Ventilators are used to assist critically ill patients with breathing. The goal is to provide adequate lung exchange without causing ventilator-induced lung injury. Three main breath patterns are recognised: continuous mandatory ventilation, continuous spontaneous ventilation and intermittent mandatory ventilation. Animals must be very carefully monitored during ventilation. PHOTO 7: A monitor allows the clinician to constantly monitor a patient's heart rate, blood pressure and other physiological components that provides information on the current state of the patient. PHOTO 8: In paediatrics incubators are used for sick puppies and kittens for external warming, oxygen supplementation and air humidification. Incubators can be used in critical care to increase the inspired oxygen concentration and allow observation and treatment of the patient at the same time. Incubators also humidify inspired gases and warm the patient. PHOTO 9: The veterinary laboratory is a place that is equipped to do diagnostic tests, to determine the severity of diseases and to assess patients’ responses to treatments.

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