Clinical Comparative Study of Effect of Two Different Doses of Phenylephrine on Spinal Induced Hypotension during Cesarean Section

Background and Aims: During Cesarean section, hypotension occurs in the most of parturients, following spinal anesthesia. This prospective observational study was undertaken to determine the efficacy of two different Bolus Doses of Phenylephrine for Prevention of Spinal-Induced Hypotension during Cesarean Section.

Materials and Methods: A total of 120 parturients undergoing cesarean section were divided into two groups of group A and group B with sixty in each group. Group A received phenylephrine 75 mcg IV bolus, while Group B received phenylephrine 100 mcg IV bolus, immediately after giving spinal anesthesia. For the next 20 minutes, systolic blood pressure (SBP), diastolic blood pressure (DSP), mean arterial pressure (MAP), and heart rate (HR) were recorded every 2 minutes, and APGAR scores at 1 and 5 minutes were recorded.

Results: There was no difference between the two groups in terms of preventing hypotension, with 16.6% in Group A and 16.6% in Group B. In the first 2–6 minutes, however, the rise in systolic pressure in Group B was higher than in Group A. Group B (46.66 %) had a higher rate of bradycardia than Group A (25 %).

Conclusion: Both phenylephrine dosages were equally effective in preventing hypotension following spinal anesthesia. However, Prophylactic bolus dose of phenylephrine 75 mcg was found to be effective for the management of spinal-induced hypotension and should be preferred over 100 mcg which causes significant bradycardia and reactive hypertension.