Effect of ketamine on intraoperative nausea and vomiting during elective caesarean section under spinal anaesthesia: A placebo-controlled prospective randomized double blinded study

PurposeThe well documented maternal and fetal safety following spinal anaesthesia in caesarean section (CS) makes it the preferred anaesthetic technique. Intraoperative nausea and vomiting in parturients subjected to CS under spinal anaesthesia is a major drawback of the technique. Post-spinal hypotension, the sympathetic blockade and associated relative vagal hyperactivity in addition to intraoperative visceral pain are the most important underlying factors behind the high rate of IONV during spinal anaesthesia. Ketamine has a unique sympathomimetic and vagolytic criteria that may help in reducing the incidence of IONV secondary to spinal-induced hypotension. This study was an attempt to evaluate the effect of ketamine on the IONV in parturients subjected to elective CS under spinal anaesthesia.Patients and methodsTwo hundred twenty-nine patients were randomly allocated into two equal groups: the ketamine group; in which 0.5 mg/kg was infused intravenously in 20 min and the placebo group; in which normal saline was infused. The two groups were given subarachnoid block with local anaesthetic hyperbaric 0.5% bupivacaine and intrathecal fentanyl.ResultsIV infusion of ketamine was associated with significant reduction in the incidence of intraoperative nausea and hypotensive episodes.ConclusionThis study demonstrated a beneficial effect of IV infusion of ketamine on IONV in parturients subjected to elective CS under spinal anaesthesia.