Obstetric Anesthesia & Analgesia Flashcards

Neonatal respiratory depression following intrathecal opioid administration is MOST associated with which agent and timing?

Answer: Fentanyl administered >4 hours before delivery

Intrathecal fentanyl given early in labor can reach peak systemic fetal levels at 4+ hours, but clinical neonatal depression is rare; morphine's delayed peak is the greater concern for late respiratory depression.

Which of the following BEST describes the mechanism of action of remifentanil as a labor analgesic?

Answer: Ultra-short-acting mu agonist metabolized by plasma esterases, self-administered by PCA

Remifentanil is an ultra-short-acting mu opioid agonist hydrolyzed by nonspecific plasma esterases, making PCA dosing feasible with rapid offset between contractions.

A parturient with a history of spinal fusion at L3-L5 requires neuraxial analgesia. The BEST alternative approach is:

Answer: Caudal epidural analgesia

Caudal epidural analgesia via the sacral hiatus avoids the fused lumbar segments and can provide effective labor analgesia when standard lumbar approaches are anatomically impossible.

Which of the following statements about oxytocin administration during cesarean is MOST accurate?

Answer: Oxytocin bolus causes transient vasodilation and hypotension; slow infusion is preferred

Rapid IV oxytocin bolus causes vasodilation, tachycardia, and hypotension due to vascular smooth muscle relaxation; a slow infusion or small divided bolus minimizes these effects.

In the setting of amniotic fluid embolism (AFE), the initial treatment priority is:

Answer: Cardiopulmonary resuscitation and management of right heart failure and coagulopathy

AFE management is supportive: CPR for cardiac arrest, vasopressors and inotropes for right heart failure, and correction of DIC with blood products are the immediate priorities.

Which drug used to treat postpartum hemorrhage is ABSOLUTELY contraindicated in a patient with hypertension?

Answer: Methylergonovine maleate

Methylergonovine causes intense vasoconstriction and is absolutely contraindicated in hypertension, preeclampsia, and Raynaud's phenomenon due to risk of severe hypertensive crisis.

When using a combined spinal-epidural (CSE) technique for labor analgesia, which statement about the 'needle-through-needle' technique is correct?

Answer: The spinal needle is passed through the epidural needle after epidural space identification

In the needle-through-needle CSE technique, the epidural space is identified first, then a longer spinal needle is passed through the epidural needle to reach the intrathecal space.