EDAIC Obstetric Anesthesia and Analgesia 3 — Questions and Answers
Question 1: What is the recommended left lateral tilt angle for a term pregnant patient undergoing general anesthesia to prevent aortocaval compression?
- 5-10 degrees
- 15-30 degrees (Correct answer)
- 45-60 degrees
- Full lateral decubitus
Correct answer: 15-30 degrees
Left lateral tilt of 15-30 degrees (typically using a wedge under the right hip) effectively displaces the gravid uterus off the aorta and inferior vena cava.
Question 2: A parturient receives magnesium sulfate for eclampsia prophylaxis. Which finding would prompt immediate magnesium discontinuation?
- Serum Mg 4-6 mEq/L
- Respiratory rate of 10/min (Correct answer)
- DTRs present but sluggish
- Urine output 35 ml/hr
Correct answer: Respiratory rate of 10/min
Respiratory rate below 12/min indicates respiratory depression from hypermagnesemia and requires immediate cessation and calcium gluconate administration.
Question 3: Which statement about remifentanil patient-controlled analgesia (PCA) for labor is CORRECT?
- It provides equivalent analgesia to epidural
- It carries risk of maternal apnea requiring monitoring (Correct answer)
- It is contraindicated in patients with prior opioid exposure
- It has no effect on the fetal heart rate tracing
Correct answer: It carries risk of maternal apnea requiring monitoring
Remifentanil PCA can cause maternal apnea and oxygen desaturation, requiring continuous SpO2 monitoring and 1:1 nursing care.
Question 4: In a patient with placenta previa requiring cesarean delivery, which anesthetic consideration is MOST important?
- Avoid all opioids
- Prepare for massive hemorrhage and have blood products ready (Correct answer)
- Regional anesthesia is absolutely contraindicated
- Avoid succinylcholine
Correct answer: Prepare for massive hemorrhage and have blood products ready
Placenta previa carries high risk of massive hemorrhage; large-bore IV access, crossmatched blood, and cell salvage should be prepared before incision.
Question 5: What is the most common cause of maternal death directly attributable to anesthesia in obstetrics?
- Local anesthetic systemic toxicity
- High spinal block
- Failed intubation with hypoxia (Correct answer)
- Pulmonary aspiration
Correct answer: Failed intubation with hypoxia
Failed or difficult intubation leading to hypoxia remains the leading anesthesia-related cause of maternal mortality, driving the preference for regional techniques.
Question 6: A postpartum patient develops a severe positional headache 24 hours after epidural placement. What is the definitive treatment?
- Oral caffeine 300mg
- Intravenous fluid bolus
- Epidural blood patch (Correct answer)
- Bed rest for 48 hours
Correct answer: Epidural blood patch
Epidural blood patch (injecting 15-20 ml autologous blood into the epidural space) has an ~85% success rate and is the definitive treatment for PDPH.
Question 7: Which uteroplacental characteristic is MOST relevant when selecting opioids for cesarean section spinal anesthesia?
- Molecular weight determines placental transfer
- Lipid solubility determines speed of placental transfer
- Protein binding prevents all placental transfer
- pH partitioning causes opioid trapping in fetal circulation (Correct answer)
Correct answer: pH partitioning causes opioid trapping in fetal circulation
Ion trapping occurs when fetal acidosis converts lipid-soluble opioids to ionized forms that cannot cross back, accumulating in fetal circulation.
EDAIC Obstetric Anesthesia and Analgesia 3
What is the recommended left lateral tilt angle for a term pregnant patient undergoing general anesthesia to prevent aortocaval compression?