Fundamentals & Core Concepts Flashcards

Which receptor subtype mediates the analgesic effects of opioids at the spinal cord level?

Answer: Mu (μ) receptor

Mu (μ) receptors are the primary mediators of spinal analgesia, respiratory depression, and euphoria produced by opioids.

The Fick principle for cardiac output calculation requires measurement of which variables?

Answer: Oxygen consumption, arterial O2 content, and venous O2 content

The Fick principle states that cardiac output equals oxygen consumption divided by the arteriovenous oxygen content difference.

Which property of local anesthetics determines their potency?

Answer: Lipid solubility

Lipid solubility is the primary determinant of local anesthetic potency, as it determines membrane penetration and receptor binding affinity.

During inhalation anesthesia, the blood:gas partition coefficient primarily determines:

Answer: Speed of induction and recovery

A lower blood:gas partition coefficient means less agent must dissolve in blood before equilibrium with alveolar gas is achieved, resulting in faster induction and recovery.

Which of the following best describes the mechanism of action of non-depolarizing neuromuscular blocking agents?

Answer: Competitive antagonism at the nicotinic acetylcholine receptor

Non-depolarizing NMBAs competitively block nicotinic acetylcholine receptors at the motor end plate without activating them.

The oxygen-hemoglobin dissociation curve shifts to the RIGHT in the presence of:

Answer: Increased 2,3-DPG and acidosis

Increased 2,3-DPG, acidosis (Bohr effect), hypercapnia, and elevated temperature shift the curve rightward, decreasing hemoglobin's oxygen affinity and facilitating O2 delivery to tissues.

Which phase of hepatic drug metabolism involves conjugation reactions such as glucuronidation?

Answer: Phase II reactions

Phase II metabolism involves conjugation reactions (glucuronidation, sulfation, acetylation) that typically increase drug water solubility for renal excretion.