NAVLE Canine Medicine and Surgery 3 — Questions and Answers
Question 1: A 6-year-old male Dachshund presents acutely with inability to walk in the hind limbs and deep pain perception is absent bilaterally. MRI confirms a thoracolumbar Hansen type I disc extrusion at T13-L1. What is the most critical prognostic indicator?
- Duration of clinical signs before surgery
- Body weight of the patient
- Presence or absence of deep pain perception (Correct answer)
- Degree of spinal cord swelling on MRI
Correct answer: Presence or absence of deep pain perception
Presence or absence of deep pain perception is the single most important prognostic factor; dogs with intact deep pain have >90% recovery rates while those without have significantly lower rates.
Question 2: A dog presents with polydipsia, polyuria, and a urine specific gravity of 1.006. A water deprivation test is performed; after 8 hours the USG remains 1.007. Following ADH administration, USG rises to 1.022. What is the diagnosis?
- Primary (psychogenic) polydipsia
- Nephrogenic diabetes insipidus
- Central diabetes insipidus (Correct answer)
- Renal medullary washout
Correct answer: Central diabetes insipidus
Response to exogenous ADH (desmopressin) with concentration of urine confirms the kidneys can respond, indicating deficient ADH production from the pituitary — central diabetes insipidus.
Question 3: Which breed is most predisposed to developing dilated cardiomyopathy (DCM) and typically presents with atrial fibrillation as its most common arrhythmia?
- Cavalier King Charles Spaniel
- Doberman Pinscher
- Boxer
- Irish Wolfhound (Correct answer)
Correct answer: Irish Wolfhound
Irish Wolfhounds have a very high prevalence of DCM and, due to their large atrial mass, are particularly prone to atrial fibrillation as a complicating arrhythmia.
Question 4: A 2-year-old intact male Rottweiler presents with a swollen, painful, warm prepuce. On examination, a mass is visualized within the prepuce that cannot be reduced. What is this condition called?
- Paraphimosis (Correct answer)
- Phimosis
- Balanoposthitis
- Priapism
Correct answer: Paraphimosis
Paraphimosis is the inability to retract an exposed penis back into the prepuce, causing engorgement, swelling, and risk of ischemia requiring urgent treatment.
Question 5: A dog is suspected to have toxicosis from xylitol ingestion 30 minutes ago. Which clinical signs would you expect first?
- Acute renal failure and anuria
- Hypoglycemia and seizures (Correct answer)
- Hemolytic anemia and methemoglobinemia
- Hepatic necrosis and coagulopathy
Correct answer: Hypoglycemia and seizures
Xylitol causes rapid insulin release in dogs leading to profound hypoglycemia within 30-60 minutes; hepatic necrosis can occur later with larger doses.
Question 6: A 10-year-old female Labrador Retriever presents with a history of panting, pot-bellied appearance, bilateral symmetrical alopecia, and PU/PD. Urine cortisol:creatinine ratio is elevated. Which test best differentiates pituitary-dependent from adrenal-dependent hyperadrenocorticism?
- Low-dose dexamethasone suppression test (LDDST)
- High-dose dexamethasone suppression test (HDDST) (Correct answer)
- ACTH stimulation test
- Urine cortisol:creatinine ratio
Correct answer: High-dose dexamethasone suppression test (HDDST)
The HDDST suppresses cortisol by >50% in most pituitary-dependent cases because the tumor retains some feedback sensitivity, while adrenal tumors do not suppress.
Question 7: A 5-year-old Beagle is presented with an acute abdomen and radiographs reveal a markedly distended stomach with gas and a 'double bubble' appearance. Which surgical procedure is performed to prevent recurrence after gastric decompression?
- Gastropexy (Correct answer)
- Pyloroplasty
- Gastrectomy
- Fundoplication
Correct answer: Gastropexy
Gastropexy permanently adheres the stomach to the right abdominal wall, preventing future rotation and recurrence of gastric dilatation-volvulus (GDV).
NAVLE Canine Medicine and Surgery 3
A 6-year-old male Dachshund presents acutely with inability to walk in the hind limbs and deep pain perception is absent bilaterally.
MRI confirms a thoracolumbar Hansen type I disc extrusion at T13-L1.
What is the most critical prognostic indicator?