A comparison of different doses of spinal levobupivacaine combined with S-ketamine and clonidine for elective cesarean section: a prospective, randomized, and double-blind study

ObjectivesThis study aimed to investigate the block characteristics and adverse effects of using different doses of spinal plain levobupivacaine combined with S-ketamine and clonidine during cesarean section.Patients and methodsThis prospective, randomized, controlled, double-blind clinical trial was conducted on 120 female patients scheduled for elective cesarean section. Patients were randomly assigned into three equal groups: group I received 10 mg of levobupivacaine 0.5% along with 12.5 mg of S-ketamine and 25 μg of clonidine intrathecally; group II received 7.5 mg of levobupivacaine 0.5% along with 12.5 mg of S-ketamine and 25 μg of clonidine intrathecally; and group III received 5 mg of levobupivacaine 0.5% intrathecally along with 12.5 mg S-ketamine and 25 μg clonidine. Hemodynamic parameters, the onset of the sensory block, the level of the sensory blockade, duration of the sensory block, the motor blockade and duration of the motor blockade, the quality of intraoperative analgesia, and the occurrence of side effects were recorded.ResultsComparison of onset and duration of sensory block did not reveal any significant differences among the groups. Duration of motor blockade and the time to first analgesic request was significantly longer in group I than in groups II and III, and it was significantly longer in group II than in group III. The incidence of intraoperative nausea, vomiting, pruritus, and shivering was comparable in all groups. As regards hypotension, there was a significant reduction in its incidence in group III compared with groups I and II. As regards bradycardia, there was a significant reduction in its incidence with decreasing dose of levobupivacaine (group III showed the least incidence).ConclusionSpinal anesthesia using small doses of levobupivacaine with a combination of S-ketamine and clonidine was effective in cesarean section both intraoperatively and postoperatively with less adverse effects.