COMPARISON OF PROPHYLACTIC ANGIOTENSIN-II VERSUS EPHEDRINE INFUSION FOR PREVENTION OF MATERNAL HYPOTENSION DURING SPINAL-ANESTHESIA

OBJECTIVE: Our purpose was to study the efficacy of ephedrine versus a ngiotensin II prophylactic infusions to counter maternal hypotension t hat occurs during spinal anesthesia at cesarean delivery. STUDY DESIGN : Healthy pregnant women undergoing elective repeat cesarean delivery at term with spinal anesthesia were randomized either to a control gro up (n = 10) or to one of two prophylactic infusion groups: angiotensin II (n = 10) or ephedrine (n = 10). Prophylactic infusions were titrat ed to a maternal diastolic blood pressure 0 to 10 mm Hg above baseline . Maternal and fetal blood samples for angiotensin II levels and acid- base status were obtained. Student's t test, chi(2), and analysis of v ariance were used. RESULTS: Mean arterial pressures were maintained af ter spinal anesthesia in the ephedrine and angiotensin II groups but d ecreased (p < 0.05) in the control group. Maternal angiotensin II leve ls rose with angiotensin II infusions but were unaltered in the other groups. Umbilical artery and vein angiotensin II levels were unaltered by angiotensin II infusions. Mean umbilical artery blood pH was lower (p < 0.05) in the ephedrine group than in the angiotensin II and cont rol groups. CONCLUSIONS: In the healthy term fetus there is an advanta ge in using angiotensin II to maintain maternal blood pressure during regional anesthesia.