Effects of intravenous midazolam during spinal anaesthesia for caesarian section

Abstract

Background: Spinal anaesthesia for caesarian section is associated with hypotension, bradycardia, and nausea and vomiting. The study was done to evaluate the safety and efficacy of sub hypnotic dose of midazolam in prevention of intraoperative complication of caesarian section under spinal anaesthesia. Methods: In this study one group of women (N=250) received midazolam 0.02 mg /kg bolus immediately after delivery of baby and 0.01 mg/kg half hourly. Equal number of women who received placebo was taken as control group. Intraoperative emetic episodes, scores of sedation and mephentermine consumption were recorded. Results: Proportions of intraoperative nausea and vomiting were 12% and 51% in midazolam and control groups respectively (p<0.0001). To maintain the haemodynamic stability the requirement of mephentermine was significantly less in midazolam receiving women (p<0.0001). Twelve women of control group and no women of midazolam group required atropine. The number of patients that required tramadol 50 mg or more for chest pain, shoulder pain and headache was significantly lesser in midazolam group than in control group (p<0.001). Oxygen supplementation was necessary for more number of women of midazolam group (14%) than of control group (2.8%). Conclusions: Sub hypnotic doses of midazolam are safe and significantly reduce the incidence and severity of hypotension, bradycardia, nausea, vomiting and chest pain during caesarian section under spinal anaesthesia. Routine supplementation of oxygen may be necessary when midazolam is used.