surgery Flashcards
you are presented with a 6yo MN Golden Retriever with a 1cm dermal mass on lateral aspect of forelimb just above elbow. The owner reports the mass has been preset for 2-3 weeks and seems to fluctuate in size. You take some FNAs from the mass and cytology shows sheets of round cells with darkly staining cytoplasmic granules.
A) what is your tentative diagnosis
B) why might this lesion fluctuate in size
C) what would be your treatment of choice for this dog
D) what further investigations would you perform prior to this treatment
E) explain why you would advise the owner to send a sample for histo (1,1,1,3,4)
MCT
intermittent histamine release causes local inflammation
surgical excision possibly combined with radiotherapy or tyrosine kinase inhibitor.
FNA/biopsy of local LNs- prescapular, axillary,
Ultrasound liver and spleen, (no need to image lungs as very unlikely site of metatstasis), possible abdominal CT for mets, haematology and biochemistry for other systemic problems. Thorough clin exam of rest of body for other tumour sites.
confirm diagnosis as FNA may not be representative, grade tumour, check margins for total excision and need for revision or radiotherapy
A 6 year old male neutered springer spaniel has presented for a right sided TECA with lateral bulla osteotomy due to end stage otitis eterna/media.
A) describe 3 features of end stage otitis externa/media and list 2 other possible indications for TECA LBO surgery in dogs.
B) name two further investigations that may be indicated prior to TECA/LBO
C) discuss 3 potential (intraoperative, immediate post op or longterm post op) complications that are associated with this surgery including the mechanism that these would occur and any treatment options
D) describe the noicieptive stimulation induced by chronic ear infection and TECA surgery in dogs.
E) how could you minimise the perioperative pain experienced by this animal (5,2,9,5,9)
3 features-epithelial hyperplasia, dysplastic calcicifcation, increased apocrine gland activtity, decreased sebacous gland activity, eventual stenosis.
Other indications- neoplasia of the horizontal canal, failed lateral wall resection or vertical canal ablation, stenosis of the horizontal canal
further investigations- MRI, culture and sensitivity, BAER test (deafness), myrigiotomy
Complications- damage to the facial nerve leading to facial paralysis- time for the nerve to heal, may never heal depending on damage eye lubrication until recovers, wound dehisence due to drainage of infection or self excoriation, regular cleaning, buster collar bandage to immobilise, resolve external infection before surgery if possible, remove stitches and allow to heal by secondary intention if possible. vestibular syndrome from trauma to epitympanic recess, usulally esolves, nystagmus over days, head tilt within weeks, paraural absecess (may be years post due to residual epithelium or cartilage (surgical drainage/debridement)
pain- premedicate with morphine or pethidine, local anaesthetic in incision at end suyrgery, continue morphine and NSAIDS post op, ketamine, fentanyl CRI or bolus, local blocks
name 3 different types of feeding tube suitable for placement in the anorexic dog giving one advantage and one disadvantage for each.
following gastric or intestinal surgery in the dog how quickly should feeding be instigated and why? (9,3)
nasogastric oesophageal, gastric, duodenal, jejunal
Briefly describe what antibiotic regime you would use for the following surgical procedures, explaining your choice in each case with reference to the classification of the surgery.
A) FHNE
B) gastrotomy to remove FB
C) pyometra (2,4,6)
FHNE should be a clean surgery and thus require no antibiosis, however if there are factors during the surgery such as lots of people and movement that may increase the risk of wound contamination, cefquinome would be a good choice every 90 minutes during the surgery.
Gastrotomy could either be clean contaminated or contaminated depending on the amount of spillage from the GI tract, antibiosis during the procedure would be appropriate with potentiated amoxycillin. assuming minimal contamination, oral potentiated amoxycillin should be continued for 5 days post op, (IV if not eating.) Metronidazole should also be given for 5 days post op, to reduce inflammation in the gut and to cover anaerobic organisms.
Pyometra is a potentially dirty surgery as the uterus contains a large amount of infectious material and neutrophilic inflammation. Likely to be E. coli or Staph Aureus. The uterine wall is very friable, and can be at risk of rupture, especially with a closed pyo. The animal could be systemically ill with a bacteraemia, especially in a closed pyo. Antibiosis is definitely required with potentiated amoxycillin (augmentin) during the surgery every 90 mins and (if no complications), continue IV for 24- 48 hours then a 14 day course of oral potentiated ammoxycillin.
Describe with the help of simple digrams the Salter Harris classification of physeal fractures. Name three typical location for physeal fractures to occur as avulsion fractures and give three principles of physeal fracture repair. (6,3,3)
I - Straight across; II - Above; III - Lower; IV - Through; V - ; VI - Crushed/Rammed
Tibial Crest, Olecranon, Calcaneus, medial maleolus of tibia, patella
Immobilise, no movement between fragments; Perfect reduction; counteract avulsion force.
You take a VD radiograph for the BVA hip dysplasia scoring scheme.
A) Which information has to be visible on the final radiograph.
B) On your first film you see that the animal is rotated. Which anatomical structures do you assess to make that decision and how are they affected when the animal is rotated to the left?
C) Explain the term Bilabiation. (5,4,3)
Date, animal microchip/ID number, ruler, left/right marker, kennel club number.
Iliac wings and obturator foramen. Increased size of left iliac wing, reduced size of obturator foramen on left.
New bone formation on the cranial curvature of the cranial acetabular edge to create a new second lip.
- A 10-year-old MN DSH cat presents to your clinic as an emergency. The owners suspect a road traffic accident. The first thing that you notice about the cat is moderate dyspnoea.
a) What are your differential diagnoses for dyspnoea in this patient? (5 marks)
b) Discuss your initial stabilisation of this patient. (5 marks)
c) Describe your diagnostic approach to the respiratory problems of this cat. Include possible findings. (10 marks)
d) Discuss your surgical management of this case if a diaphragmatic hernia is diagnosed (10 marks).
A)- diaphragmatic hernia
- pulmonary contusions
- pneumothorax
- haemothorax
- fractured ribs
B) Briefly triage, assessing neurological, cardiovascular and respiratory status. Assuming the cat is not immediately critical-
Place the cat in an oxygen tent if possible and allow to calm down, handling dyspnoeic cats can lead to sudden collapse through hypoxia.
If the cat will tolerate it, I would try and place a pulse oximeter to analyse saturation.
When the cat appears less dyspnoeic (no mouth breathing, paroxysmal abdominal effort, exaggerated effort, tachypnoea, well saturated), I would perform a full clinical examination to look for other injuries and to assess the cardiovascular stability of the patient.
I would try and get IV access in case the patient needed fluid therapy for hypvolaemia (haemothorax), or collapsed, however causing the cat distress should be avoided.
If necessary/possible, I would try and provide some pain relief for the cat (buprenorphine).
- A 10-year-old MN DSH cat presents to your clinic as an emergency. The owners suspect a road traffic accident. The first thing that you notice about the cat is moderate dyspnoea.
a) What are your differential diagnoses for dyspnoea in this patient? (5 marks)
b) Discuss your initial stabilisation of this patient. (5 marks)
c) Describe your diagnostic approach to the respiratory problems of this cat. Include possible findings. (10 marks)
d) Discuss your surgical management of this case if a diaphragmatic hernia is diagnosed (10 marks).
A)- diaphragmatic hernia
- pulmonary contusions
- pneumothorax
- haemothorax
- fractured ribs
B) Briefly triage, assessing neurological, cardiovascular and respiratory status. Assuming the cat is not immediately critical-
Place the cat in an oxygen tent if possible and allow to calm down, handling dyspnoeic cats can lead to sudden collapse through hypoxia.
If the cat will tolerate it, I would try and place a pulse oximeter to analyse saturation.
When the cat appears less dyspnoeic (no mouth breathing, paroxysmal abdominal effort, exaggerated effort, tachypnoea, well saturated), I would perform a full clinical examination to look for other injuries and to assess the cardiovascular stability of the patient.
I would try and get IV access in case the patient needed fluid therapy for hypvolaemia (haemothorax), or collapsed, however causing the cat distress should be avoided.
If necessary/possible, I would try and provide some pain relief for the cat (buprenorphine).
- Full general history (including previous respiratory problems, or any nasal discharges, as well as any ongoing conditions)
- Specific history (when, did they see, how status of cat is changing)
- Full clinical examination (general), assess general stability of patient and look for other injuries, including those that may alter priorities.
- Specific clinical exam (respiratory auscultation, quiet- pneumothorax (ping?), haemothorax, palpate ribs gently, HR, RR,
- Monitoring equipment, pulse oximeter, possibly consider arterial blood gases, haematology, biochemistry for other electrolyte abnormalities etc
- Conscious radiographs or thorax and abdomen especially, looking for hernia, air, haemo, ribs, contusions.
- If that is not possible could attempt ultrasound for fluid, diaphragm, etc.
- thoracocentesis is possible if air or fluid suspected, and allows you to assess fluid type.
D)
- Write short notes on the following general anaesthetic agents with particular reference to their clinical use and systemic effects.
a) Isoflurane (6 marks)
b) Sevofluorane (6 marks)
Isoflurane- GABA agonist, inhalational anaesthetic agent, hydorcarbon, liquid with vapour at room temp, more potent, minimally metabolised (excreted in lungs largely unchanged), little effect on vital organs, but does cause vasodilation, marked decrease in respiratory rate
Sevofluorane- GABA agonist, faster onset and offset, easier to titrate, much more expensive, less potent, need higher MAC, mild decrease in cardiac contractility, increases RR, decreased tidal volume, bronchodilatory, can be used to induce, ONLY LICENSED FOR DOGS
- During an ovariectomy of a 2-year-old Labrador you notice some bleeding from the falciform ligament and the surface of the spleen following inadvertent scalpel penetration when opening the abdomen. You are considering surgical haemostasis.
a) Describe the main difference between monopolar and bipolar electrocautery and list one advantage of each method (4 marks)
b) Give two appropriate and different methods of haemostasis for the splenic incision (2 marks)
c) List two suture materials that have good knot security for ligation of the ovarian pedicle (2 marks)
d) Describe two manoeuvres that can be used to examine the ovarian pedicles for haemorrhage before abdominal closure (2 marks)
e) List how you would monitor this patient postoperatively if you suspect ongoing haemorrhage (2 marks)
Monopolar cautery involves an electric current between the instrument and a metal plate under the dog. It can be used for cutting as well as cautery, but risks burns to the animal where the current earths.
Bipolar cautery involves a current between two prongs on the instrument and provides more precise cautery, however it cannot be used for cutting. Doesn’t disturb other electrical body rhythms (like the heart) and can aid coagulation using pressure.
Pressure using swabs is an appropriate measure in this case assuming there are no obvious vessels to ligate or clamp. It needs to be applied for 5 minutes and can be aided by ice cold saline or phenylephrine soaked swabs.
An oxidised cellulose powder or dressing could be applied to the wound to aid haemostasis as it acts as a chemical aid to haemostasis and a sealant.
Suture materials with good knot security are often multifilament with low memory such as vicryl (polygalactin 910), polyester?
Duodenal manoeuvre, colic manoeuvre grab duodenum and move left to expose r pedicle, grab colon and move right to expose l pedicle
Regular TPR (min hourly) to assess for hypovolaemia including CRT, mms, monitor Pcv q 12 h, could perform quick abdominal ultrasound to look for fluid. Assess bleeding through wound onto primapore. Return to surgery and assess stumps if very worried.
- A 7-year-old cat presents with an aural mass which is confirmed on biopsy to be an aural polyp.
a) List two treatment options for an aural polyp in a cat (4 marks)
b) Give two indications for surgical treatment (4 marks)
c) Using diagrams demonstrate the difference between the middle ear in the cat and dog. (4 marks)
Pull with traction with or without steroids,destroys vascular supply, ventral bulla osteotomy.
Recurrent polyps or polyps with radiographically changes or neurological signs.
Cat has two compartments, larger ventromedial and smaller dorsolateral compartment that has he tympanic membrane. Connected by small fissure in the bone septum, sympathetic fibres run along the promontary hat is next to the bone septum that separates the compartments.
Name two general indications (4 marks) and the five basic principles for performing an arthrodesis (5 marks).
a)Which condition commonly occurs in large-breed dogs after a jump or a fall from a height and requires treatment with a carpal arthrodesis? (3 marks)
Chronic osteoarthritis/djd leading to pain in a joint with minimal movement.
Ligament instability leading to pain that can’t be fixed by conservative means.
Untreatable fractures
Chronic luxations
Partial neuro injuries
Debride cartilage
Place cancellous bone graft
Immobilise under compression
Stabilise at appropriate angle (plan prior to surgery on conscious animal)
Additional rigid external fixation until radiographically evidence of bony union
Hyperextension of the carpus leading to traumatic luxation of the carpus leading to damage of the palmar ligaments and a palmigrade stance. It may involve any or all of the antibrachiocarpal, middle carpal and carpo-metacarpal joints.
Explain how to insert a lag screw (10 marks) and which screw can be used as a lag screw? (2 marks)
A lag screw is a primary repair inserted into a larger hole than the screw so it only engages the far cortex causing inter fragmentary compression.
It follows the principle of drill measure tap screw. It is mainly used for metaphyseal and epiphyseal fragments (must be used with a plate in the diaphysis) it should be placed to neutralise any forces on the fragments and cause compression (generally at 90 degrees if there is no muscle forces). To do this a screw is measured, and a hole is drilled through the fragments with the same diameter of the core of the screw as the thread hole. Either a partially threaded screw is placed, or the near cortex is over drilled using a drill bit the same width as the threads on the screw.
A positive profile Imex screw is used that can be partially threaded (the distal end) or fully threaded.
Briefly describe the three phases of small intestinal wound healing and identify the time period when intestinal wound dehiscence and leakage is most likely to occur (6 marks).
b) List five reasons why healing may be more problematic in the oesophagus compared to the small intestine (5 marks).
c) Name the suture holding layer of the small intestine (1 mark).
A) Lag phase - 1-4 days, suture material results in a fibrin clot which holds the intestines together for the initial stage post surgery. Seals wound but little intrinsic strength, so delay in the proliferative stage means this can fail and then result in dehiscence days 2-5 post surgery.
Proliferative stage - days 3-14 post surgery, fibroblasts are recruited to the wound and begin to lay down collagen resulting in rapid gain in wound strength, 80% by day 14.
Maturation phase - day 14 to 180, reorganisation and remodelling of the collagen within the wound returns the layered structure of the intestinal wound to normal.
Factors that delay include compromise to the blood supply, traumatic surgical technique, inversion or eversion of the wound edges.
B) lack of serosa impairs wound healing, lack of omentum, segmental blood supply, respiratory and peristaltic movements, tension at surgical site.
C) submucosa
A 7 year old Bassett Hound presents with presumed ovarian remnant syndrome following ovariohysterectomy for pyometra 8 months previously:
a) List the clinical signs associated with this condition (3 marks)
b) Describe how you would make a definitive diagnosis (4 marks)
c) Briefly describe the treatment (3 marks)
d) How do you avoid this condition? (2 marks)
Comes into oestrus-intermittent bloody vaginal discharge, attracts entire males, behavioural change, occasional perineal alopecia.
Induction of ovulation using hCG can assist finding of remnant tissue.
Vaginal smear looking for cornification on cytology.
A blood test for estradiol if high levels can be a positive indication but low levels can be seen in the blood regardless and less accurate than vaginal smear.
When not in heat can give GnRH and look for progesterone.
Surgical removal- midline celiotomy, ovarian stump resection and removal of any suspect other parts of tissue. Routine closure.
Avoid by ensuring entire ovary removed during surgery (ensure can palpate entire ovary) and care not to drop any tissue in abdomen as removing.
Briefly describe the three phases of small intestinal wound healing and identify the time period when intestinal wound dehiscence and leakage is most likely to occur (6 marks).
b) List five reasons why healing may be more problematic in the oesophagus compared to the small intestine (5 marks).
c) Name the suture holding layer of the small intestine (1 mark).
lag phase- (days 0–4), in which the acute inflammatory response clears the wound of debris
proliferation phase- phase of fibroplasia (days 3–14), in which fibroblasts proliferate and immature collagen is laid down
maturation phase- (day 10 onwards), in which collagen remodels.
dehiscence most likely 2-5 days after surgery as the fibrin clot breaks down and the proliferation of granulation tissue hasn’t started.
- acidic reflux from stomach
- no serosa
- segmental blood supply no anastamoses
- constant swallowing and respiration movements
- lack of omentum
- tension at surgical site
submucosa is the suture holding layer
- You are presented with a 12 month old Pug that presents with cyanosis and inspiratory stridor. You suspect severe BOAS (Brachycephalic obstructive airway syndrome)
a) How would you initially manage this patient? (6 marks)
b) Describe in detail how you would investigate this patient once stable, giving reasons why and comparing with normal anatomy. (12 marks)
c) Select one surgical corrective technique and discuss how you would perform this including reference to complications (6 marks)
d) Discuss the difference between laryngeal paralysis and laryngeal collapse. Which of these conditions is this dog likely to have? Give your reasons.
(6 marks)
- triage airway, breathing, circulation, neurological status
- Give oxygen (via mask, nasal prongs, free pass, et tube if allows intubation, urinary catheter if cant pass tube)
- sedate if stressed, consider induction of GA to intubate and provide oxygen
- get IV access
- full oral and laryngeal examination using laryngoscope to assess laryngeal collapse
- give IV steroids, (and bronchodilators eg clenbuterol) to reduce inflammation and improve airway access.
Once stable, good physical exam including oral examination (ideally concious to assess laryngeal collapse but sedated/GA if necessary to avoid stress and decompensation). May need radiographs to assess trachea, pulmonary oedema, cardiomegaly and diaphragmatic hernia.
- often see stenotic nares
- elongated dorsal soft palate
- everted layngeal saccules
- tonisllar hypertrophy
- layngeal collapse
- pharyngeal hyperplasia
- hypoplastic trachea
- You are presented with a 12 month old Pug that presents with cyanosis and inspiratory stridor. You suspect severe BOAS (Brachycephalic obstructive airway syndrome)
a) How would you initially manage this patient? (6 marks)
b) Describe in detail how you would investigate this patient once stable, giving reasons why and comparing with normal anatomy. (12 marks)
c) Select one surgical corrective technique and discuss how you would perform this including reference to complications (6 marks)
d) Discuss the difference between laryngeal paralysis and laryngeal collapse. Which of these conditions is this dog likely to have? Give your reasons.
(6 marks)
- triage airway, breathing, circulation, neurological status
- Give oxygen (via mask, nasal prongs, free pass, et tube if allows intubation, urinary catheter if cant pass tube)
- sedate if stressed, consider induction of GA to intubate and provide oxygen
- get IV access
- full oral and laryngeal examination using laryngoscope to assess laryngeal collapse
- give IV steroids, (and bronchodilators eg clenbuterol) to reduce inflammation and improve airway access.
Once stable
A 7 year old Bassett Hound presents with presumed ovarian remnant syndrome following ovariohysterectomy for pyometra 8 months previously:
a) List the clinical signs associated with this condition (3 marks)
b) Describe how you would make a definitive diagnosis (4 marks)
c) Briefly describe the treatment (3 marks)
d) How do you avoid this condition? (2 marks)
Comes into oestrus-intermittent bloody vaginal discharge, attracts entire males, behavioural change, occasional perineal alopecia.
Induction of ovulation using hCG can assist finding of remnant tissue.
Vaginal smear looking for cornification on cytology.
A blood test for estradiol if high levels can be a positive indication but low levels can be seen in the blood regardless and less accurate than vaginal smear.
When not in heat can give GnRH and look for progesterone.
Surgical
- You are presented with a 12 month old Pug that presents with cyanosis and inspiratory stridor. You suspect severe BOAS (Brachycephalic obstructive airway syndrome)
a) How would you initially manage this patient? (6 marks)
b) Describe in detail how you would investigate this patient once stable, giving reasons why and comparing with normal anatomy. (12 marks)
c) Select one surgical corrective technique and discuss how you would perform this including reference to complications (6 marks)
d) Discuss the difference between laryngeal paralysis and laryngeal collapse. Which of these conditions is this dog likely to have? Give your reasons.
(6 marks)
.
- A 4 month-old puppy suffers a fracture of the lateral aspect of the humeral condyle.
a) Describe the aetiology of this fracture. (3)
b) What treatment principles should be followed for this type of fracture? (2)
c) Describe your pre-, intra-, and post-operative treatment plan for this dog. (10)
d) Suggest three specific paediatric anaesthetic considerations (3) and suitable methods in which each consideration can be managed. (6)
e) How would you provide multimodal intra-operative analgesia to this
animal (include suggestions on techniques and the drug you would administer; however, doses are NOT necessary)? (6)
A) Likely to be falling from a height as the force of the impact travels up the radius which then communicates with the lateral aspect of the humerus. This force causes it to fracture resulting in a Salter Harris type fracture, likely IV or II.
B) early surgery, articular integrity more important, careful surgery so be gentle, germinal cells on the epiphyseal fragment so be delicate, some can be done by external coaptation, implants need to minimally disrupt the physis, no implant that compresses the physis, remove when healed.
C) pre op - full clinical exam to assess for concurrent injuries, orthopaedic examination with neurological exam, radiographs mediolateral and craniocaudal, assess growth plate, classify and see if any other abnormalities present. Give opiate and non steroidal analgesia until the operation is undertaken and ensure the animal is stable. Use external coaptation to protect the leg if surgery is chosen. Maybe preoperative bloods if worried about the systemic status of the patient but can delay surgery until patient is stable.
Intra op - some salter Harris fractures can be adequately reduced with external coaptation, appropriate analgesia intraoperatively, two K wires and a tension band wire, screw across the fracture. Delicate surgery, hold leg up to relax muscles and allow for better reduction, have radiographs present in theatre. Intraoperative antibiosis of cefuroxime.
Post op - analgesia, radiographs and return to surgery if apposition or alignment not right. Protective melanin on surgical site. Short walks just for toilet 3-4x daily. Home in two days, strict cage rest, return in 4-6 weeks for radiographs to assess activity, alignment and apparatus. Can start increasing activity once fracture shows adequate healing. Check for premature growth plate closure, could lead to angular limb deformity.
D) hypothermia due to large surface area to body ratio - HME, hotdog, temperature monitoring, bubble wrap, hot hands if needed, monitor on recovery, return to pen once greater than 37.
Hypoglycaemia - young age, less glycogen reserves as liver immature and higher metabolic rate - wait until six hours before surgery before stopping food intake, check glucose before surgery and then during it if worried. Add dextrose to IVFT if low.
Reduced cardiovascular compensation, cannot increase stroke volume, only heart rate which gets reduced to anaesthetic drugs - use drugs that affect the cardiovascular system the least during the surgery.
E) model for multimodal analgesia includes Opiate to NSAID to local analgesia and then any adjuncts. I would use pethidine in my premed that would continue part way into the surgery, I would already have it on a non steroidal such as meloxicam, then during the surgery I would give it a brachial plexus nerve block. If this does not work I would have a fentanyl CRI or a ketamine CRI after giving an initial bolus of each if the local analgesia did not work. Finally, I would monitor the pain response with BP monitoring, hr and rr monitoring.
- You are asked by the senior partners of the small animal practice you are working in to evaluate their anaesthetic monitoring and suggest improvements. At present monitoring consists of a nurse who occasionally feels the animal’s pulse when they are passing the animal during the operation and in recovery. Why might this not be sufficient? Discuss how you would go about improving this. What monitors do you feel would give the best cost benefit and why? (30)
Not sufficient- doesnt allow you to track and respond to patterns, no information on depth, heart rate, BP, RR, paO2, so the first sign of a problem will be a change in the pulse (or worse a complete lack of pulse), that may not be noticed for a long period of time. Doesnt allow you to intervene early and solve problems before they become serious.
Recording- invaluble tool, very cheap, requires a nurse or SQP to do the recording, but they should be present anyway!
- You are presented with a 2 year-old neutered male terrier with acute onset vomiting. On clinical examination, the dog is dehydrated and jaundiced with a rapid respiratory rate and abdominal pain. A blood sample shows a normal haematology screen but marked elevation in hepatic enzymes.
a) What are your differential diagnoses for acute vomiting and acute marked elevation in liver enzymes? Please give two separate lists, one for vomiting (10) and one for marked increase in liver enzymes (5). Indicate which differentials are most likely in this case.
b) What emergency treatment would you institute in this case and what further work-up would you advise when the dog is clinically stable? (5)
c) Further work up, unusually, demonstrates that this dog has a ruptured diaphragm with a trapped liver lobe and gall bladder in the chest. You now want to perform surgery. List your main considerations for anaesthesia (5) and surgery (5) in this case.
Vomiting differentials: is it vomiting to begin with or is it regurgitation or pharyngeal retching.
Central - stimulation of chemoreceptor trigger zone e.g. By apomorphine, cardiac glycoside or toxins (uraemia, liver disease, bacterial toxins), metabolic disorders (ketoacidosis). Stimulation of the vomiting centre by CNS disease (neoplasia, inflammation, increased CSF pressure, epilepsy). Vestibular input. Stimulation by higher centres such as fear, stress or pain.
Gastric and intestinal disease - dietary indiscretion, diet change, over eating, toxins, infectious (parvovirus, adeno, distemper, panleucopaenia, FIP, lepto, salmonella, roundworms, hookworms), gastric FB, gd/v, motility disorders, haemorrhagic gastroenteritis.
Extra-abdominal - acute pancreatitis, acute hepatitis, acute renal disease/urinary tract obstruction/uraemia, pyometra, peritonitis.
Metabolic/endocrine - Addison’s, hypokalemia, hypercalcaemia, diabetic ketoacidosis, hyperthyroidism.
Raised liver enzymes:
Acute hepatocellular necrosis diseases - toxic like paracetamol, carprofen, diazepam, mebendazole, mercury. Infectious - CAV-1, neonatal herpes virus, bacterial. Endotoxaemia. Thermal. Metabolic - copper storage disease, infarction.
Acute hepatic necrosis - hypoxia, cholestasis, septicaemia, pancreatitis, IBD, infectious - FIP, salmonella, lepto, Clostridia, heroic his, toxoplasma, aspergillosis.
No necrosis - hepatic lipidosis in cats, diffuse neoplasia.
B) quick history on vaccination, worming, access to toxins, likely to eat a foreign body. Oxygen, little stress, fluids hartmanns, assess dehydration and hypovolaemia, replace fluids at 10ml/kg boluses until stable. Replace rest of dehydration over next 24 hours and account for vomiting loss. ABG for electrolytes and acid base, correct those that need correcting. Haem and biochem for added information. Then X-rays when stable, ultrasound of abdomen, potentially endoscopy depending on signs. Liver biopsy if suspicions lead that way and no obvious cause and coagulation times are normal. Anti vomiting drugs, gastroprotectants.
C) anaesthesia - liver compromise so hypoglycaemia, hypoproteinaemia, coagulations, detoxification of drugs etc, respiratory compromise, hypovolaemia and dehydration, surgery will enter the thorax, acid base as electrolyte abnormalities, may be hypoxaemic. Vomiting resulting in oesophagi this, potential regurgitation and aspiration pneumonia.
Surgery - liver lobe may need to be removed, will have to check for necrosis of gall bladder and liver, can remove upto 70% liver and the gall bladder if bile can still get out.
Diaphragm needs to be closed, will have to check integrity when closed with saline, adhesions may be present with liver.
Blood loss as near large blood vessels in the cranial abdomen. Coagulation times may be askew.
Reperfusion injury possible, do not untorse organs when removing them from the thoracic cavity.
Other organs may be affected and displaced, pancreatitis likely.
- What are the 4 commonest sites in the appendicular skeleton for osteosarcomas to occur? (4) List treatment options including prognosis (8).
Distal radius, proximal humerus, proximal and distal femur and tibia.
Two aims, either curative or palliative:
Palliative options - Euthanasia - most metastasised by time of diagnosis and cause a lot of pain so give analgesia and when too much euthanasia.
Radiotherapy - palliative radiotherapy to try and give more time.
Metronomic chemotherapy - carob plating and doxorubicin are the usual chemotherapy drugs.
Limb amputation due to fractures present but likely to spread already.
Curative - likely to have metastasised but if caught early it is possible:
Limb amputation or limb sparing surgery. Chemotherapy is usually needed.
- Construct a simple diagram depicting the principle components of haemostasis (individual clotting factors / cascade not required). (6) Briefly outline the clinical signs you might expect to result from a failure of primary haemostasis (3) and secondary haemostasis. (3)
1ry haemostasis - vWF binds to exposed basement membrane and collagen, leads to platelet adhesion leading to shape change leading to granule release of ADP and TxA2, this recruits more platelets and aggregation results in the platelet plug.
2ry haemostsis - tissue factor is released from fibroblasts and activation of vWF to initiate the extrinsic pathway of secondary haemostasis. This results in the cascade, and factor X activation resulting in thrombin activation. The thrombin causes amplification of the cascade due to activation of other clotting factors which then results in the propagation of fibrinogen conversion into fibrin leading to the fibrin clot and secondary haemostasis.
Clinical signs of primary - petechial and ecchymotic haemorrhages in skin, muscles and sclera, haematuria, occult blood in faeces, occ CNS bleeding.
Clinical signs of secondary - haemorrhage - bruising, abdominal haemorrhage, anaemia, haematuria, blood into intestines, death.
- A young healthy dog undergoing anaesthesia for a routine procedure suffers a cardiopulmonary arrest immediately following the administration of an induction agent. What is your immediate response in terms of basic life support? (12)
Stop providing any drugs (induction agent)
(THE)Call for help, check the time,
A Intubate (provide an airway, if cant get ET tube in, use urinary catheter to provide some oxygen)
B Provide IPPV using 100% oxygen (10bpm)
C Cardiovascular compressions (dog in lateral, 120-150
bpm)
Attach capnograph (1st choice), then ECG, then any extra monitoring (pulse ox, BP), assess as people swap over (5s max)
D Reverse any drugs if possible (atipamazole for alpha 2 agonists, naloxone for opiods, ensure no anaesthetic gases being used)
D If in Ventricular fibrillation (ONLY), consider defibrillation,
E consider epinephrine (mainly for vasoconstrictory effect), or atropine (inotropic effect). May take 5-10 minutes to have effect, care not to overdose. If no IV access (should have in this situation), can place down ET tube at 10x dose)
Continue compressions in rhythm of staying alive in two minute cycles, swapping the person to prevent them becoming tired and ineffective. Use capnograph to monitor efficiency of compressions. When capnorgraph C02 shoots up, stop as has own cardiovascular output.
If animal recovers, do not attempt surgery on it that day. Monitor closely to avoid re crash.
- What methods and techniques can be used to control acute bleeding during a surgical procedure? (12)
Pressure - digital with swabs, do not wipe and moist swabs better.
Haemostatic forceps - halstead, criles - smallest forceps capable of doing the job, curved forceps improve visibility, small superficial bleeds use the tips, deep bleeders use the jaw.
Ligation - use square or surgeon knot, correct number of throws, enough tension to prevent slippage, smallest size suture capable of doing the job, cut the end short (3mm).
Vascular clips - vessels upto 5mm, vessel should be dissected free from the surrounding tissue, diameter should be no more than two thirds or less than one third of the length of the clip, apply several mm from cut end of the vessel, veins and arteries should be clipped separately.
Electrocautery - Monopolar - less precision, more likely to get burns, can’t use in a wet field and small vessels only.
Bipolar - less current and does not pass through the patient, not in a wet field and larger vessels than Monopolar but not too large. Enteral which are bigger versions of bipolar and can cauterise up to 7mm.
Topical Haemostatic agents - liver, spleen, cancellous bone and others - collagen, cellulose, gelatin and wax.
A 10 year old neutered male Labrador retriever presents to you as an emergency because of sudden onset severe breathing difficulty during a walk. On clinical examination, the dog is very dyspnoeic with markedly increased respiratory sounds and cyanosis.
a. Describe your emergency assessment and immediate treatment of this case on admission. (4 marks)
b. What are your differential diagnoses for dyspnoea in this case? (6 marks)
c. Following stabilisation of the patient, briefly discuss the diagnostic steps you would undertake to confirm your clinical suspicion of laryngeal paralysis in this case. (10 marks)
d. Outline the possible treatment options for laryngeal paralysis. (5 marks)
Emergency assessment - airway, breathing, circulation etc.
Stabilisation - oxygen, cool, destress, sedation, IV steroids, emergency thoracocentesis, anaesthetise and et tube, temporary tracheostomy.
Ddx - laryngeal paralysis, tracheal collapse, inhaled foreign body, trauma, gd/v, anaphylaxis, laryngeal collapse, laryngitis, laryngeal neoplasia, cervical neoplasia, pneumonia, lung lobe torsion, atrial fibrillation, cardiac dysrhythmias, acute pancreatitis, addisonian episode.
History - previous surgery, polyneuropathy, classical signs.
Clinical examination including neurological exam - inspiratory strider, laryngeal strider, inspiratory dyspnoea, altered phonation, exercise intolerance, collapse, cyanosis, gagging/coughing, polyneuropathy signs.
CBC, serum biochemistry including electrolytes and serum T4.
Thoracic radiographs to rule out megaoesophagus, pulmonary disease, neoplasia.
Cervical radiographs - rule out neoplasia and assess calcification of laryngeal cartilages.
Direct laryngoscopy is gold standard and under very light plane of anaesthesia and watch for paradoxical movement. Ventral recumbency, narrow resting rima glottidis, oedema/erythema of the arytenoids, one or both arytenoids fail to abduct on inspiration, forced passive movement on expiration.
Ultrasound for talented radiographers.
Treatment options - once stable, medical or reduce weight, improve fitness, no excess exercise especially on hot days, treat hypothyroidism, steroids for polyneuropathy, walk with harness, fed moist food indefinitely.
Surgical, tie back - unilateral arytenoid lateralisation - permanent sutures from one side of arytenoid to cricoid and or thyroid cartilage.
For the following organs, briefly discuss the ideal properties of a suitable suture material and name one such material (2 marks for each).
a. skin b. small intestine c. oral mucosa d. muscle
Skin - needs to be as strong as the tissue and skin is one of the strongest tissue types, heals to sufficient strength in 7-10 days, want monofilament as less risk of tracking infection in and less tissue drag so less inflammation. Nylon.
Small intestine - weaker tissue, small suture wanted to protect and not cause too much inflammation, monofilament for less tissue drag and less infection risk. PDS
Oral mucosa - quite easy to pull through, not very strong but only need support for around a week as little support needed. Want something nonirritant due to location in the mouth, polygalactin 90 aka vicryl.
Muscle - supports itself after 15-20 days, absorbable needed, good blood supply, monofilament has less tissue drag. Polydiaxone.
a. Describe, with the aid of a diagram, the anatomy of the inguinal ring in the dog. (7 marks)
b. List the structures that normally pass through the inguinal ring in male dogs. (3 marks)
Two inguinal rings, the external and internal inguinal rings - external is formed as a hole in the aponeurosis of the external abdominal oblique and bordered by the ilio-posts muscle. Internal is a gap bordered cranially by internal abdominal oblique, dorsally by the inguinal ligament and prepublication tendon and ilio-psoas muscle. Bordered medically by the lateral border of rectus abdominus.
External inguinal ring - vaginal tunic and contents, external pudendal artery and vein, and genitofemoral nerve.
Internal inguinal ring - femoral vessels and nerve, iliopsoas.
Cruciate disease is a common orthopaedic problem in dogs.
a. Which three joint movements does the intact cranial cruciate ligament prevent? (3 marks)
b. List typical findings on orthopaedic examination of dogs with this problem: (5 marks)
c. Meniscal injury often accompanies cruciate disease – which meniscus is more commonly effected and why? (2 marks)
Inward rotation, cranial displacement of femur and mediolateral displacement.
Medial buttress, pain on manipulation, cranial drawer, tibial thrust, reduced range of movement, crepitus if secondary OA, swelling of joint capsule.
Medial meniscus as it has an extra ligamentous attachment to the medial collateral so restricted range of movement
Some pelvic fractures can be managed conservatively with cage rest. List criteria which should be considered when deciding whether pelvic fractures require surgical treatment and state why they are important (10 marks)
Affect weight bearing axis
Working or breeding dog
A 5 year old Flemish lop-eared rabbit is presented for major dental surgery. Describe the considerations you should take in to account when anaesthetising this patient (5 marks) and suggest an anaesthetic regime for this animal (5 marks).
.
In table form compare alfaxalone and propofol as anaesthetic agents in cats, considering both their physical properties and their effects on the animal.
(5 marks each drug)
.
Write short notes on the signalment (or predisposing factors), clinical signs and diagnosis of the following orthopaedic diseases:
a) Panosteitis
b) Shoulder osteochondrosis
c) Septic arthritis (10)
Panosteitis - 2mths to 5yrs, dogs only, GSD predisposed. 2-14days of acute lameness, often shifting, potentially associated with adipose bone marrow disease, degeneration of medullary adipocytes, increase in stromal cells and intra membranous ossification. See on radiography, thumb print on the bone of radio dense oval on the diaphyses of the long bones.
Shoulder OCD - failure of endochodreal ossification or abnormal differentiation of cartilage into bone resulting in thickened area of cartilage in epiphysis or metaphysis. Can fissure and detach resulting in osteochondrosis dissecans - 2nd most common location, giant breeds and collies, 4-8months, females more, shoulder muscle atrophy, pain on extension. Predisposing factors include high calories, increased calcium, ad lib feeding, genetic factor. Diagnosis on radiography or advanced imaging, most common site is the caudal humeral head which flattens or the caudal glenoid. Can see joint mice in the bicipital groove, thickened cartilage and subchondral bone defects, osteochondrosis fragments, peripheral osteophytes.
Septic arthritis - painful acute lameness of the one limb. Usually a local wound that has entered the joint, rarely hameatogenous. Puppies can get it from omphalophlebitis and usually have other septicaemia signs, adults have a local wound or rarely systemically ill etc. diagnosis by joint tap, increased neutrophils that may be degenerate, see bacteria is rare but possible, total protein is increased. Radiography may show widening of the joint.
You are presented with a five month old Labrador Retriever with a history of mild left thoracic limb lameness of three weeks’ duration. Palpation of the elbow region seems to be painful.
a) List the differential diagnoses in order of likelihood.
b) Outline your approach to the diagnosis of this case. (10)
1 - Elbow dysplasia with either an ununited anconeal process, medial compartment/coronoid precess disease, or osteochondrosis of the medial humeral condyle.
Subchondral cystic lesion; 2- over exertion and associated sprain/fatigue of the limb, 3- shoulder osteochondrosis, 4- bicipital groove tenosynovitis, muscle bruising, pad lesion, fracture of the sesamoid bones if present or one of the metacarpals of the paw.
History - trauma, diet, exercise, how did it start, given any meds, what have they done with him since, got better or worse, better or worse at certain times of the day?
Clinical exam - full systemic, then ortho and neuro, look all over etc.
Radiography - localised with clin exam, radiographs, contrast potentially into joint, look for change (describe).
Advanced imaging - CT, sclerosis more easily seen.
