Low dose spinal anaesthesia for caesarean section in parturients having pregnancy induced hypertension: Effect on haemodynamicre sponse and vasopressor requirement: A prospective randomized double blind case control study

Abstract

Currently, the safety of spinal anaesthetic techniques is well established for caesarean section in pregnancy induced hypertension (PIH) patient. Addition of fentanyl to local anaesthetic allows achievement of adequate anaesthesia with lower dose of local anaesthetic in spinal anaesthesia, thereby reducing the occurence of hypotension and need for vasopressor. A prospective, randomized, double blind, case control study was carried out in 80 parturients having PIH undergoing caesarean section in spinal anaesthesia were randomized into 2 groups depending on intrathecal drug received by them as Group C (Conventional dose group- received hyperbaric bupivacaine 10 mg)and Group L{low dose group, hyperbaric bupivacaine (7.5 mg) with fentanyl (25 mcg)} and compared regarding sensory- motor block characteristics, incidence of hypotension (fall in MAP > 25% from baseline) vasopressor requirement Phenylephrine and Ephedrine. Patient in Group L had significantly less number of hypotension episodes as compared to Group C(20 vs 31, p= 0.011). Hence vasopressor requirement was also significantly less in Group L than in Group C [Phenylephrine (1600 mcg vs 2500 mcg, p=0.044), Ephedrine (66 mg vs 18 mg, p= 0.030)].Low dose spinal anaesthesia using 7.5 mg hyperbaric bupivacaine with 25 mcg fentanyl seems to be superior alternative to conventional dose of 10 mg hyperbaric bupivacaine for caesarean section in parturients having pregnancy induced hypertension, because it was associated with better hemodynamic stability, reduced vasopressor requirement.