Circulatory Responses to propofol-ketamine combination compared to propofol alone for sedation during spinal anaesthesia

The present study was undertaken to establish the efficacy of low dose ketamine infusion in combination with propofol in maintaining hemodynamic stability when used for sedation during spinal anaesthesia compared to propofol alone. Sixty adult with ASA physical status I and II patients undergoing urological procedures were studied after giving informed consent. Patients receiving spinal anaesthesia with 0.5% bupivacaine were randomly assigned to sedation with propofol - ketamine [Group I (n=30)] or propofol only [Group II (n=30)]. Group I patients received a loading dose of propofol (0.4 mg/kg) and ketamine (0.1 mg/kg) followed by a continuous infusion of low dose propofol (1.2 mg/kg/hr) and ketamine (9.3 mg/kg/hr) whereas group II patients received a bolus dose of propofol (0.5 mg/kg?) only followed by a continuous infusion of propofol (1.5 mg/kg/hr). Monitored parameters included: heart rate, systolic blood pressure, diastolic blood pressure and sedation scores rated on a five point scale. Parameters were recorded at baseline and at predetermined intervals of 5, 10, 15, 20, 25, 30, 45, 60, 75 and 90 minutes after spinal anaesthesia. Heart rate, systolic and diastolic blood pressure were all significantly higher in group I patients at various intervals as compared to group II patients. Sedation scores revealed no significant difference at the predetermined time intervals between the two groups. In conclusion, the propofolketamine combination confers hemodynamic stability during spinal anaesthesia as compared to Propofol alone.