VTNE Anesthesia Management 4 — Questions and Answers
Question 1: A rabbit is being anesthetized and develops respiratory arrest. What anatomical feature makes rabbits particularly prone to apnea under anesthesia?
- Large tidal volume
- Obligate nasal breathing and a narrow glottis (Correct answer)
- Absence of a laryngeal reflex
- High functional residual capacity
Correct answer: Obligate nasal breathing and a narrow glottis
Rabbits are obligate nasal breathers with a narrow glottis and strong laryngospasm reflex, making airway management and intubation challenging and apnea more common.
Question 2: Which reversal agent is used to antagonize the effects of medetomidine in dogs?
- Naloxone
- Flumazenil
- Atipamezole (Correct answer)
- Neostigmine
Correct answer: Atipamezole
Atipamezole is a selective alpha-2 adrenergic antagonist used to reverse the sedative and cardiovascular effects of medetomidine and dexmedetomidine.
Question 3: What does a PaO2 of 60 mmHg indicate in a patient breathing 100% oxygen?
- Normal oxygenation
- Mild hypoxemia
- Severe respiratory impairment (Correct answer)
- Acceptable for induction
Correct answer: Severe respiratory impairment
A PaO2 of 60 mmHg while breathing 100% oxygen indicates severe pulmonary dysfunction, as a normal patient should achieve PaO2 values of 450–600 mmHg.
Question 4: Which of the following best describes the role of a vaporizer in an anesthetic machine?
- It humidifies inspired gases to prevent airway drying
- It converts liquid anesthetic agent into a precise vapor concentration for delivery (Correct answer)
- It absorbs CO2 from exhaled gases
- It regulates oxygen flow from the tank
Correct answer: It converts liquid anesthetic agent into a precise vapor concentration for delivery
The vaporizer converts liquid inhalant anesthetic into a calibrated vapor concentration delivered to the patient via the breathing circuit.
Question 5: In a cat with hypertrophic cardiomyopathy (HCM), which anesthetic protocol component should be AVOIDED?
- Opioid premedication
- Tachycardia-inducing agents (Correct answer)
- Isoflurane maintenance
- Local nerve blocks
Correct answer: Tachycardia-inducing agents
Tachycardia reduces diastolic filling time in HCM patients, worsening obstruction and cardiac output; agents like ketamine or anticholinergics should be avoided.
Question 6: When performing a ring block for a digit surgery in a dog, which complication is most likely if epinephrine is included in the local anesthetic?
- Methemoglobinemia
- Ischemic necrosis of the digit (Correct answer)
- Systemic hypertension
- Prolonged motor blockade
Correct answer: Ischemic necrosis of the digit
Epinephrine causes vasoconstriction, which in end-arterial areas like digits can lead to ischemia and necrotic tissue damage.
Question 7: A patient undergoing general anesthesia develops bradycardia with a heart rate of 30 bpm. Which drug should be administered first?
- Lidocaine
- Atropine (Correct answer)
- Dobutamine
- Propranolol
Correct answer: Atropine
Atropine is the first-line anticholinergic agent used to treat anesthetic-induced bradycardia by blocking parasympathetic input to the heart.
VTNE Anesthesia Management 4
A rabbit is being anesthetized and develops respiratory arrest.
What anatomical feature makes rabbits particularly prone to apnea under anesthesia?