Comparative Study Among Ephedrine, Norepinephrine and Phenylephrine Infusions to Prevent Spinal Hypotension During Cesarean Section. A Randomized Controlled Double-Blind Study

Background: Spinal anesthesia is the recommended technique in elective cesarean sections. Usage of vasopressors is more widely accepted as an effective method for decreasing postspinal hypotension than fluid loading. However, the ideal vasopressor to prevent spinal hypotension during cesarean section has been a subject of much debate. It should maintain maternal blood pressure and placental perfusion, with minimal adverse effect on fetus and mother. Aim: The primary aim was to compare the effect of prophylactic infusion of phenylephrine versus norepinephrine versus ephedrine in the prevention of postspinal hypotension in elective cesarean section. The secondary aim was to assess their effects on neonate. Methods: Seventy-five patients were enrolled in this study and randomly divided into three groups. Group P received phenylephrine infusion and group N received norepinephrine infusion, while group E received ephedrine infusion. The changes in mean arterial blood pressure and heart rate were recorded throughout the surgery. Maternal and neonatal perioperative complications were controlled and recorded. Results: MAP were higher in the ephedrine group than the phenylephrine and norepinephrine groups. Maternal tachycardia was significantly more common in ephedrine, and bradycardia was more common in phenylephrine group without significant difference. Nausea and vomiting were more common in ephedrine group. Neonatal acidosis was lesser in phenylephrine and norepinephrine groups than in the ephedrine group. Conclusion: Prophylactic infusion of phenylephrine and norepinephrine can be successfully used to prevent postspinal hypotension in parturient undergoing cesarean section with less drawbacks and fetal well-being than ephedrine.