Obstetric Anesthesia Flashcards

What is the preferred anesthetic technique for cesarean delivery in most elective cases?

Answer: Spinal anesthesia

Spinal anesthesia is preferred for elective cesarean delivery because it provides rapid onset, dense block, avoids airway instrumentation, and allows the mother to remain awake.

At approximately what gestational age is an obstetric patient considered to have a full stomach and at increased aspiration risk during anesthesia?

Answer: 14 weeks

From approximately 14 weeks gestation, progesterone-induced lower esophageal sphincter relaxation and uterine compression of the stomach increase aspiration risk.

Which vasopressor is currently recommended as the first-line treatment for spinal hypotension during cesarean delivery?

Answer: Phenylephrine

Phenylephrine is the first-line vasopressor for spinal hypotension in obstetrics because it maintains uteroplacental blood flow better than ephedrine and is associated with less fetal acidosis.

What dermatome level of sensory blockade is required for adequate spinal anesthesia during cesarean delivery?

Answer: T4

A sensory block to T4 (nipple line) is required for cesarean delivery to cover peritoneal manipulation and uterine exteriorization.

Which local anesthetic is most commonly used for spinal anesthesia in obstetric patients undergoing cesarean delivery?

Answer: Bupivacaine 0.75% hyperbaric

Hyperbaric bupivacaine 0.75% is the most widely used spinal local anesthetic for cesarean delivery due to its reliable dense block, predictable spread, and long duration.

What physiological change in pregnancy most significantly decreases the MAC requirement for volatile anesthetic agents?

Answer: Elevated progesterone levels

Elevated progesterone levels during pregnancy decrease MAC requirements for volatile anesthetics by approximately 25-40% through CNS depressant effects.

What is the most common cause of maternal mortality directly related to obstetric anesthesia in developed countries?

Answer: Failed or difficult airway management

Failed or difficult airway management during general anesthesia remains the leading direct anesthesia-related cause of maternal mortality due to airway changes in pregnancy.