To Compare the Effects of IV Bolus Doses Phenylephrine, And Ephedrine Injection in Maintaining Arterial Blood Pressure During Spinal Anesthesia for Cesarean Sections-A Randomized Comparative Study

Abstract

Spinal anesthesia is the preferred anesthetic approach for cesarean sections due to its benefits for both the mother and fetus. However, hypotension is a common and potentially harmful complication. Phenylephrine (PE) is frequently used as a vasopressor to manage hypotension during spinal anesthesia, but it can cause maternal sinus bradycardia. This study aimed to compare two strategies for maintaining arterial blood pressure during cesarean delivery: a 20 mcg bolus of phenylephrine followed by a 10 mcg/min infusion (Group P) versus a 6 mg bolus of ephedrine followed by a 0.1 mg/min infusion (Group E). A total of 100 pregnant women scheduled for elective or emergency cesarean sections under spinal anesthesia were randomly assigned to either Group P or Group E. Systolic blood pressure was well-maintained in both groups during the first 20 minutes. After this period, Group P’s blood pressure stabilized towards basal values, while Group E's remained slightly above basal levels—a statistically significant difference (p < 0.005). Diastolic blood pressure fell in both groups, but Group E maintained slightly higher levels than Group P. Group P had a 24% incidence of bradycardia requiring atropine, while no such cases were observed in Group E. Despite these differences, overall maternal arterial blood pressure was effectively maintained in both groups, with no significant difference in uterine tone or bleeding levels.