BCSE - Basic and Clinical Sciences Examination Principles of Anesthesia Questions and Answers

Question 1

Which of the following factors would most likely DECREASE the Minimum Alveolar Concentration (MAC) of an inhalant anesthetic?

Accepted Answer

Administration of an opioid premedication

Answer

Hyperthermia

Answer

Hypernatremia

Answer

Use of CNS stimulants like ephedrine

Question 2

During a canine exploratory laparotomy under general anesthesia, the capnograph reading abruptly drops from 40 mmHg to 5 mmHg, accompanied by sudden hypotension and tachycardia. Which of the following is the most likely cause?

Accepted Answer

A massive pulmonary thromboembolism

Answer

Esophageal intubation

Answer

Exhaustion of the CO2 absorbent

Answer

Anesthetic machine leak

Question 3

Anesthetized hypotension in a healthy patient, defined as a mean arterial pressure (MAP) below 60 mmHg, is most commonly caused by which of the following?

Accepted Answer

Peripheral vasodilation and myocardial depression from anesthetic agents

Answer

Inadequate surgical stimulation

Answer

Excessive intravenous fluid administration

Answer

Hypoventilation leading to hypercarbia

Question 4

A veterinarian needs to provide standing sedation for a 650 kg dairy cow. When choosing to use xylazine, an alpha-2 adrenergic agonist, which of the following statements is most accurate?

Accepted Answer

Cattle are highly sensitive to xylazine, requiring approximately one-tenth the dose used in horses.

Answer

Cattle are highly resistant to xylazine, requiring doses 10 times higher than those for horses.

Answer

The primary, FDA-approved reversal agent for xylazine in cattle is atipamezole.

Answer

Xylazine provides potent sedation in cattle but has no analgesic properties.

Question 5

What is the primary function of the soda lime granules within the canister of a rebreathing anesthetic circuit?

Accepted Answer

To chemically absorb exhaled carbon dioxide.

Answer

To absorb waste anesthetic gas, preventing environmental pollution.

Answer

To humidify the inspired gases to prevent desiccation of the airways.

Answer

To vaporize the liquid anesthetic into a gas for delivery to the patient.

Question 6

Which of the following best describes the mechanism of action for local anesthetics such as lidocaine and bupivacaine?

Accepted Answer

They block voltage-gated sodium channels, preventing nerve impulse propagation.

Answer

They activate potassium channels, leading to hyperpolarization of the nerve membrane.

Answer

They antagonize NMDA receptors at the level of the spinal cord.

Answer

They irreversibly destroy the myelin sheaths along the axons.