COMPARISON OF INTRAVENOUS BOLUS PHENYLEPHRINE, EPHEDRINE AND MEPHENTERMINE FOR MAINTENANCE OF ARTERIAL PRESSURE DURING SPINAL ANAESTHESIA IN CAESAREAN SECTION

BACKGROUND Caesarean section under spinal anaesthesia is commonly associated with hypotension, which can be detrimental to mother and foetus. It is the responsibility of the anaesthesiologist to ensure stable arterial blood pressure throughout surgery to avoid any decrease in maternal organ blood flow and placental insufficiency. Due to the absence of definitive evidence showing absolute clinical benefit of one over the other, especially in emergency and high-risk caesarean sections, we did examine the effect of intravenous bolus doses of vasopressor agents for maintenance of arterial pressure during spinal anaesthesia in caesarean section today. MATERIALS AND METHODS Vasopressors are the cornerstone in treatment of hypotension during spinal anaesthesia. Phenylephrine, alpha 1 agonist, ephedrine and mephentermine, a direct and indirect acting sympathomimetic can be used to increase the arterial blood pressure. The present study aims to compare the effect of phenylephrine, ephedrine and mephentermine for maintenance of arterial blood pressure. RESULTS The study shows that three vasopressors can be used for the indication of hypotension. The clinical outcomes like neonatal Apgar score, incidence of nausea and vomiting and other adverse events were comparable with both the vasopressors. Phenylephrine however has the advantage of decreased heart rate and requirements of lesser amount and more efficacy at maintaining the arterial blood pressure. The systolic blood pressure was significantly higher with phenylephrine 6 minutes after administration compared to mephentermine. CONCLUSION Mephentermine should be avoided in patients in whom increased heart rate may be undesirable. Phenylephrine seems to be a better choice for the treatment of hypotension during spinal anaesthesia.