In a 24-year-old primiparous woman undergoing an elective cesarean section with spinal anesthesia who develops hypotension after 5 minutes, the best initial treatment (best fetal pH) after ensuring adequate left uterine displacement would be

In a 24-year-old primiparous woman undergoing an elective cesarean section with spinal anesthesia who develops hypotension after 5 minutes, the best initial treatment (best fetal pH) after ensuring adequate left uterine displacement would be

• A. Phenylephrine
• B. Ephedrine
• C. Epinephrine
• D. 1000 mL D5LR

Answer: (A)

Spinal-induced hypotension after neuraxial anesthesia is best treated first by restoring maternal mean arterial pressure to improve uteroplacental perfusion. After placing the patient with left uterine displacement, a vasopressor that raises blood pressure quickly is ideal. Phenylephrine, a selective alpha-1 agonist, increases systemic vascular resistance and blood pressure rapidly without causing a detrimental rise in fetal metabolic demand. This tends to preserve fetal oxygenation and acid-base status, yielding a better fetal pH than alternatives that elevate heart rate or cardiac output. While a fluid bolus can help in some cases, relying on a large volume infusion alone is less reliable for correcting neuraxial hypotension and carries risks of fluid overload.

Spinal-induced hypotension after neuraxial anesthesia is best treated first by restoring maternal mean arterial pressure to improve uteroplacental perfusion. After placing the patient with left uterine displacement, a vasopressor that raises blood pressure quickly is ideal. Phenylephrine, a selective alpha-1 agonist, increases systemic vascular resistance and blood pressure rapidly without causing a detrimental rise in fetal metabolic demand. This tends to preserve fetal oxygenation and acid-base status, yielding a better fetal pH than alternatives that elevate heart rate or cardiac output. While a fluid bolus can help in some cases, relying on a large volume infusion alone is less reliable for correcting neuraxial hypotension and carries risks of fluid overload.