VTNE Anesthesia Management 3 — Questions and Answers
Question 1: What is the recommended endotracheal tube cuff inflation pressure to prevent tracheal damage in small animals?
- Less than 5 cmH2O
- Less than 20 cmH2O (Correct answer)
- Less than 50 cmH2O
- Greater than 30 cmH2O
Correct answer: Less than 20 cmH2O
Cuff pressure should be maintained below 20–25 cmH2O to prevent ischemic necrosis of the tracheal mucosa from excessive pressure.
Question 2: Which inhalant anesthetic has the highest blood:gas partition coefficient among those commonly used?
- Desflurane
- Sevoflurane
- Isoflurane
- Halothane (Correct answer)
Correct answer: Halothane
Halothane has the highest blood:gas partition coefficient (~2.4) among common inhalants, resulting in slower induction and recovery compared to newer agents.
Question 3: A dog's capnograph waveform shows an elevated baseline (above zero during inspiration). What does this indicate?
- Esophageal intubation
- CO2 rebreathing (Correct answer)
- Hypoventilation
- Endobronchial intubation
Correct answer: CO2 rebreathing
An elevated capnograph baseline indicates the patient is inhaling CO2, consistent with rebreathing due to exhausted CO2 absorbent or an incompetent expiratory valve.
Question 4: Which drug class is CONTRAINDICATED in patients with pheochromocytoma undergoing anesthesia?
- Opioids
- Benzodiazepines
- Acepromazine (Correct answer)
- Propofol
Correct answer: Acepromazine
Acepromazine blocks alpha-adrenergic receptors, which can unmask beta-adrenergic effects of catecholamines from a pheochromocytoma, causing severe hypotension and tachycardia.
Question 5: During equine anesthesia in dorsal recumbency, the horse develops hypoxemia despite 100% oxygen delivery. What is the most likely cause?
- Malignant hyperthermia
- Ventilation-perfusion mismatch (Correct answer)
- Carbon monoxide poisoning
- Equipment failure
Correct answer: Ventilation-perfusion mismatch
Dorsal recumbency in horses causes significant V/Q mismatch because the weight of abdominal organs compresses the dependent lung, impairing gas exchange.
Question 6: What is the primary mechanism by which opioids provide analgesia in veterinary patients?
- Blocking sodium channels in peripheral nerves
- Binding to mu, kappa, and delta receptors in the CNS and periphery (Correct answer)
- Inhibiting cyclooxygenase enzymes
- Blocking NMDA receptors
Correct answer: Binding to mu, kappa, and delta receptors in the CNS and periphery
Opioids primarily act by binding to opioid receptors (mu, kappa, delta) in the brain, spinal cord, and peripheral tissues to inhibit pain transmission.
Question 7: Which of the following is a sign of an excessively light plane of anesthesia in a dog?
- Absent palpebral reflex
- Mydriasis
- Slow, regular respirations
- Purposeful movement in response to stimulation (Correct answer)
Correct answer: Purposeful movement in response to stimulation
Purposeful movement in response to a surgical stimulus indicates the patient is too light and may be aware of pain; anesthetic depth should be increased.
VTNE Anesthesia Management 3
What is the recommended endotracheal tube cuff inflation pressure to prevent tracheal damage in small animals?