Prophylactic angiotensin II infusion during spinal anesthesia for elective cesarean delivery

Area of Science:

• Obstetrics and Gynecology
• Anesthesiology
• Pharmacology

Background:

• Hypotension during regional anesthesia in obstetric patients is a clinical challenge.
• Angiotensin II is a potential alternative to traditional vasopressors due to potentially lower uterine vasoconstriction.
• This study investigated the efficacy and safety of prophylactic angiotensin II versus ephedrine infusion.

Purpose of the Study:

• To compare the effects of prophylactic angiotensin II and ephedrine infusions on maternal hemodynamics.
• To evaluate fetal status at delivery following administration of either angiotensin II or ephedrine.
• To determine the safety and efficacy of angiotensin II in managing spinal anesthesia-induced hypotension in parturients.

Main Methods:

• Fifty-four women undergoing elective cesarean delivery under spinal anesthesia were randomized.
• Participants received either continuous intravenous infusion of angiotensin II or ephedrine.
• Infusion rates were adjusted to maintain maternal systolic blood pressure between 90-100% of baseline.

Main Results:

• Maternal heart rate was significantly lower in the angiotensin II group compared to the ephedrine group (P < 0.001).
• Umbilical arterial and venous blood pH and base excess were significantly higher in the angiotensin II group (P < 0.05).
• Lower cumulative vasopressor doses were required in the angiotensin II group.

Conclusions:

• Angiotensin II infusion effectively maintained maternal systolic blood pressure during spinal anesthesia.
• Angiotensin II did not increase maternal heart rate and avoided fetal acidosis.
• Angiotensin II represents a promising vasopressor for managing hypotension in obstetric anesthesia.