MAC Pediatric & Obstetric Anesthesia 2 — Questions and Answers
Question 1: Which drug is contraindicated in patients susceptible to malignant hyperthermia?
- Propofol
- Nitrous oxide
- Succinylcholine (Correct answer)
- Fentanyl
Correct answer: Succinylcholine
Succinylcholine is a known trigger for malignant hyperthermia and is absolutely contraindicated in susceptible patients.
Question 2: What is the treatment of choice for malignant hyperthermia?
- Beta-blockers IV
- Dantrolene sodium IV (Correct answer)
- Calcium gluconate IV
- Magnesium sulfate IV
Correct answer: Dantrolene sodium IV
Dantrolene sodium prevents calcium release from the sarcoplasmic reticulum, halting the hypermetabolic crisis of malignant hyperthermia.
Question 3: What spinal level should be achieved for effective first-stage labor analgesia with an epidural?
- T10-L1 (Correct answer)
- T4-T8
- L1-L3
- T6-T10
Correct answer: T10-L1
A T10-L1 sensory block covers the uterus and cervix, providing effective analgesia during the first stage of labor.
Question 4: What is the primary risk of using neuraxial opioids for labor analgesia?
- Fetal heart rate changes only
- Maternal respiratory depression and pruritus (Correct answer)
- Permanent spinal cord injury
- Uterine hyperstimulation
Correct answer: Maternal respiratory depression and pruritus
Neuraxial opioids can cause maternal respiratory depression and pruritus due to opioid receptor activation and potential systemic absorption.
Question 5: Which obstetric emergency most urgently requires immediate operative delivery?
- Mild preeclampsia at term
- Umbilical cord prolapse (Correct answer)
- Gestational diabetes
- Mild oligohydramnios
Correct answer: Umbilical cord prolapse
Cord prolapse causes fetal compression and hypoxia requiring immediate delivery, often necessitating urgent general anesthesia if neuraxial isn't established.
Question 6: Which vasopressor is preferred for treating obstetric spinal hypotension based on uteroplacental blood flow effects?
- Ephedrine
- Phenylephrine (Correct answer)
- Dopamine
- Norepinephrine
Correct answer: Phenylephrine
Phenylephrine preserves uteroplacental blood flow better than ephedrine in most obstetric cases and is now preferred for treating spinal hypotension in cesarean delivery.
MAC Pediatric & Obstetric Anesthesia 2
Which drug is contraindicated in patients susceptible to malignant hyperthermia?