Comparison of Passive Leg Raising and Intravenous Phenylephrine as Prophylaxis in the Prevention of Hypotension After Spinal Anaesthesia in Elective Caesarean Section: A Randomized Controlled Trial.

Background and objectives Post-spinal hypotension (PSH) is most commonly encountered in patients undergoing lower-segment caesarean section (LSCS). Passive leg raising (PLR) has been attempted in septic shock to predict fluid responsiveness. PLR is a novel and less-tried manoeuvre to prevent PSH in patients undergoing LSCS. This study aimed to compare the efficacy of PLR and prophylactic phenylephrine infusion in preventing PSH. Methods With the Ethical Committee's approval and patient consent, this randomized controlled trial included 180 parturients undergoing elective LSCS. The effects of PLR and phenylephrine infusion were compared. Parturients in the leg elevation group received leg raising approximately 30 cm from the horizontal position with a wooden block for three minutes. Parturients in the phenylephrine group received phenylephrine infusion at 100 µg/minute for three minutes following subarachnoid block. Those in the control group did not receive any intervention. Baseline systolic and diastolic blood pressure and heart rate were recorded every minute for three minutes and then every three minutes until the delivery of the foetus. Fetal appearance, pulse, grimace, activity and respiration (APGAR) score were noted at the first and fifth minute following birth. Any episodes of hypotension, hypertension or bradycardia were recorded. Results The incidence of hypotension was maximum in the control group (n = 23, or 38.3%), followed by the phenylephrine group (n = 4, or 6.7%) and least in the leg elevation group (n = 3, or 5.0%). The difference in the incidence rates was statistically significant (p < 0.05). The incidence rates of hypertension and bradycardia were not significant in any of the groups. The neonatal outcome was the same in all three groups. Conclusion PLR is a better alternative to prophylactic phenylephrine infusion in preventing PSH.