Efficacy of Phenylephrine in Preventing Hemodynamic Responses of Oxytocin during Elective Cesarean Section: A Randomized, Double-Blind, Controlled Trial

Abstract

This study compared hemodynamic changes and occurrence of complications following oxytocin administration with a prior injection of phenylephrine 100 μg or normal saline during elective cesarean section. Sixty-six healthy term parturients with uncomplicated, singleton pregnancy undergoing elective cesarean section under spinal anesthesia were studied. They received either intravenous phenylephrine 100 μg or normal saline before oxytocin 3 IU was administered over 30 seconds. Oxytocin dose was repeated depending on the adequacy of uterine tone. There was no significant change in systolic, diastolic, and mean arterial pressures during the initial 3 minutes following oxytocin administration in the phenylephrine group but a significant fall in mean and diastolic pressures in the saline group. Heart rate did not change significantly, and no significant complications occurred in either of the groups. To conclude, phenylephrine 100 μg administered before oxytocin injection maintained hemodynamic parameters better than normal saline injection during elective cesarean section.

Keywords

oxytocin - phenylephrine - cesarean section - hemodynamic changes - blood pressure

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