DVM Anesthesia and Pain Management 4 — Questions and Answers
Question 1: Which inhalant anesthetic agent has the LOWEST blood-gas partition coefficient among those currently used in veterinary medicine?
- Halothane
- Isoflurane
- Sevoflurane
- Desflurane (Correct answer)
Correct answer: Desflurane
Desflurane has the lowest blood-gas partition coefficient (0.42), resulting in the fastest induction and recovery, though it is rarely used in veterinary practice.
Question 2: A goat is anesthetized for rumenotomy. Which unique physiologic concern requires special positioning and management?
- Risk of hypoglycemia from fasting
- Regurgitation and aspiration due to forestomach contents (Correct answer)
- Tachycardia from rumen gas pressure
- Hypercalcemia from calcium mobilization
Correct answer: Regurgitation and aspiration due to forestomach contents
Ruminants are highly prone to regurgitation and passive reflux under anesthesia; head elevation and rapid intubation with a cuffed tube are essential to prevent aspiration.
Question 3: Which analgesic modality is MOST appropriate for managing chronic osteoarthritis pain in a senior dog with concurrent renal insufficiency?
- Meloxicam long-term at full dose
- Gabapentin as an adjunct analgesic (Correct answer)
- Aspirin at anti-inflammatory doses
- Corticosteroids at immunosuppressive doses
Correct answer: Gabapentin as an adjunct analgesic
Gabapentin is renally excreted but is generally safer than NSAIDs in patients with renal insufficiency; NSAIDs reduce renal prostaglandins and can worsen renal function.
Question 4: During an isoflurane anesthetic in a cat, the vaporizer dial reads 2.5% but the EtCO2 is 60 mmHg. What is the MOST appropriate immediate intervention?
- Increase isoflurane to deepen the plane
- Manually ventilate or increase ventilator rate to correct hypoventilation (Correct answer)
- Administer doxapram as a respiratory stimulant
- Decrease the oxygen flow rate on the circuit
Correct answer: Manually ventilate or increase ventilator rate to correct hypoventilation
EtCO2 of 60 mmHg indicates hypoventilation; the correct response is to assist or control ventilation to normalize CO2, not to change anesthetic depth.
Question 5: What is the PRIMARY reason acepromazine is contraindicated as the sole sedative in a dog with suspected pheochromocytoma?
- It potentiates opioid-induced respiratory depression
- It blocks alpha-1 receptors, causing vasodilation that unmasks catecholamine hypertension (Correct answer)
- It lowers the seizure threshold
- It causes direct myocardial depression
Correct answer: It blocks alpha-1 receptors, causing vasodilation that unmasks catecholamine hypertension
Acepromazine's alpha-1 blockade can precipitate a hypertensive crisis in pheochromocytoma patients by unmasking the unopposed beta-adrenergic effects of catecholamine surges.
Question 6: A 12-year-old dog with mitral valve disease (MMVD) requires anesthesia for tooth extraction. Which induction protocol is MOST appropriate?
- Mask induction with isoflurane for rapid control
- Propofol IV titrated to effect after premedication (Correct answer)
- Ketamine/diazepam IV combination
- Thiopental IV bolus
Correct answer: Propofol IV titrated to effect after premedication
Propofol titrated IV allows careful dose adjustment to minimize cardiovascular depression in a compromised patient; mask induction causes stress and uncontrolled changes in depth.
Question 7: Which statement BEST describes the concept of 'preemptive analgesia' in veterinary pain management?
- Administering analgesics only after the patient shows pain behaviors
- Providing analgesia before a noxious stimulus to reduce central sensitization and postoperative pain (Correct answer)
- Using the highest safe dose of analgesics during surgery regardless of procedure
- Replacing general anesthesia with local blocks for all procedures
Correct answer: Providing analgesia before a noxious stimulus to reduce central sensitization and postoperative pain
Preemptive analgesia involves giving analgesics before a painful stimulus to prevent wind-up and central sensitization, resulting in lower postoperative pain scores.
DVM Anesthesia and Pain Management 4
Which inhalant anesthetic agent has the LOWEST blood-gas partition coefficient among those currently used in veterinary medicine?