comparison of prophylactic infusion of phenylephrine with ephedrine for prevention of hypotension in elective cesarean section under spinal anesthesi: a randomized clinical trial

background: spinal anesthesia is an accepted technique in elective cesarean sections. however, hypotension, resulted from sympathectomy is a common problem, especially in pregnant women. prevention of this complication by sympathomimetic agents is of potential clinical significance. the aim of this study is to compare the effect of prophylactic infusion of phenylephrine versus ephedrine in the prevention of hypotension during spinal anesthesia in elective cesarean section. methods: eighty-three patients were enrolled in this study and randomly divided into three groups. group ph received phenylephrine infusion, group e received ephedrine infusion while group p were delivered placebo. vital signs (blood pressure, heart rate, and arterial oxygen saturation) were recorded throughout the surgery. maternal and neonatal perioperative complications were also controlled and recorded. results: there was an insignificant difference in demographic data between the groups. systolic and diastolic blood pressures were higher in the phenylephrine group than control, but not higher than the ephedrine group. maternal dysrhythmias were more common in ephedrine and phenylephrine groups than the control group. vomiting was more common in ephedrine group (p<0.05). in addition, the fifth-minute apgar score of neonates was higher in phenylephrine and ephedrine groups than the control group (p<0.05). neonates of phenylephrine group had less acidosis than the other groups. conclusion: prophylactic infusion of phenylephrine can effectively decrease spinal anesthesia related hypotension without any significant complication for mother or her fetus. trial registration number: irct2012120911700n1