DVM Anesthesia and Pain Management 2 — Questions and Answers
Question 1: Which opioid is MOST appropriate for providing intraoperative analgesia in a dog undergoing a painful orthopedic procedure?
- Butorphanol
- Morphine (Correct answer)
- Buprenorphine
- Tramadol
Correct answer: Morphine
Morphine is a full mu-opioid agonist providing superior analgesia for painful procedures compared to the partial agonist buprenorphine or the mixed agonist-antagonist butorphanol.
Question 2: A cat develops bronchospasm immediately after induction with ketamine and is placed on oxygen. What is the MOST likely contributing factor?
- Hypersensitivity to ketamine's preservative
- Excessive salivation causing airway obstruction
- Ketamine-induced laryngospasm in cats (Correct answer)
- Inadequate premedication with a benzodiazepine
Correct answer: Ketamine-induced laryngospasm in cats
Cats are particularly prone to laryngospasm, and ketamine increases salivary and bronchial secretions, predisposing them to airway obstruction.
Question 3: Which monitoring parameter BEST reflects the adequacy of ventilation during general anesthesia?
- SpO2 via pulse oximetry
- End-tidal CO2 (EtCO2) (Correct answer)
- Mean arterial pressure
- Heart rate
Correct answer: End-tidal CO2 (EtCO2)
EtCO2 directly reflects alveolar ventilation and CO2 elimination, making it the best indicator of ventilation adequacy.
Question 4: A horse under general anesthesia develops hypotension (MAP < 60 mmHg). After ensuring adequate depth of anesthesia, what is the FIRST-LINE treatment?
- Epinephrine IV bolus
- Dobutamine CRI
- Increase isoflurane concentration
- IV crystalloid fluid bolus (Correct answer)
Correct answer: IV crystalloid fluid bolus
IV fluid bolus is the first-line intervention to restore preload and correct anesthesia-induced vasodilation or hypovolemia before adding inotropes.
Question 5: Which local anesthetic has the LONGEST duration of action when used for a peripheral nerve block?
- Lidocaine
- Mepivacaine
- Bupivacaine (Correct answer)
- Procaine
Correct answer: Bupivacaine
Bupivacaine has the longest duration of action among commonly used local anesthetics, typically lasting 4–8 hours for nerve blocks.
Question 6: During an anesthetic episode, a dog's EtCO2 suddenly drops from 45 to 15 mmHg while heart rate and blood pressure remain stable. What is the MOST likely cause?
- Pulmonary thromboembolism
- Esophageal intubation
- Disconnection of the breathing circuit (Correct answer)
- Malignant hyperthermia
Correct answer: Disconnection of the breathing circuit
A sudden near-zero EtCO2 with stable cardiovascular parameters strongly suggests a circuit disconnect, as no CO2 is sampled from the patient.
Question 7: Which drug class is used as a constant rate infusion (CRI) to provide balanced anesthesia and reduce inhalant requirements via the concept of multimodal analgesia?
- Phenothiazines
- NMDA receptor antagonists (Correct answer)
- Loop diuretics
- Anticholinergics
Correct answer: NMDA receptor antagonists
NMDA receptor antagonists such as ketamine CRI reduce the MAC of inhalants and prevent central sensitization as part of multimodal analgesia.