Assessment of midazolam, fentanyl, or neostigmine as an adjuvant to bupivacaine spinal anaesthesia

ABSTRACT

The aim of this study is to evaluate the postoperative analgesic and side effects of intrathecal midazolam, fentanyl, and neostigmine on bupivacaine spinal blockade. A total of 60 patients undergoing lower limb surgery were randomized to one of four groups. All patients received 10mg hyperbaric bupivacaine plus 2ml of the test drug intrathecally [1T]. The control group [B] received saline as the test drug. The midazolam group [BM] received 2mg midazolam, the fentanyl group [BF] received 20ug fentanyl, and the neostigmine group [BN] received 25ug neostigmine. Extent and duration of sensory and motor blockade were evaluated. Adequacy of analgesia and incidence of adverse effects were also recorded. The groups were demographically similar. The time required for first rescue postoperative analgesic was shorten in the control group compared to the other groups [p<0.001]. The frequency of postoperative analgesic intake was significantly more in control group [p<0.001]. Preoperative sedation was noted to be significantly higher in midazolam group. More patients in fentanyl group reported pruritus, whereas more patients in neostigmine group experienced nausea and vomiting than did the other groups. The mixtures of midazolam-bupivacane, fentanyl-bupivacaine, or neostigmine-bupivacaine intrathecally lengthened postoperative analgesic duration and reduce analgesic consumption postoperative, however making choice between the three drugs, side effects related to each one must he considered and careful monitoring is mandatory