A COMPARATIVE STUDY OF PHENYLEPHRINE, MEPHENTERMINE AND NOREPINEPHRINE IN THE TREATMENT OF HYPOTENSION DURING SPINAL ANAESTHESIA FOR CAESAREAN SECTION

Background: Post-spinal hypotension is a common complication during caesarean sections under spinal anaesthesia, necessitating effective management protocols. Previous studies have explored various vasopressors, such as norepinephrine, phenylephrine, and mephentermine, to control this condition, but comparative effectiveness and safety remain under investigation. Objective: This study aims to compare the efcacy and safety of mephentermine, phenylephrine, and norepinephrine in managing hypotension during spinal anesthesia for caesarean sections. Method: A total of 114 patients undergoing elective caesarean sections were randomly assigned to three groups, Group P (phenylephrine 100 mcg IV), Group M (mephentermine 6 mg IV), and Group N (norepinephrine 6 mcg IV). Blood pressure, heart rate, and neonatal outcomes (APGAR scores) were monitored and recorded at various intervals. Each group consisted of 38 patients. The primary outcome was the maintenance of mean arterial blood pressure, while secondary outcomes included heart rate, number of bolus doses required, and APGAR scores of the newborns. Data were analyzed using the Statistical Package for Social Sciences (SPSS) version 21.0. Observations were described in terms of proportions, and statistical analysis was performed using chi-square tests and Student's t-tests where applicable. A p-value of less than 0.05 was considered statistically signicant. Age group distribution, mean age, and mean weight among the groups were compared using chi-square and ANOVA tests, respectively, with detailed results indicating no signicant differences across groups in these parameters. Results: The norepinephrine group exhibited quicker blood pressure control compared to the other groups. The mean blood pressure was higher in the norepinephrine group, with signicant differences observed in diastolic and systolic blood pressure across the study period. The phenylephrine group reported higher rates of bradycardia, while the mephentermine group showed higher incidences of tachycardia. APGAR scores were statistically similar across all groups, indicating no signicant difference in neonatal outcomes. Conclusion: Norepinephrine demonstrated superior efcacy in blood pressure management with fewer incidences of bradycardia and comparable neonatal outcomes, making it a preferable choice over phenylephrine and mephentermine for treating post-spinal hypotension during caesarean sections.