ABSTRACT

Unfortunately spinal morphine is associated with high incidence of pruritus and emetic symptoms which can limit its use. The aim of this study was to compare the efficacy of preoperative oral Gabapentin versus tropisetron on postoperative nausea and vomiting after major abdominal surgery under combined spinal and general anesthesia.

Ninety patients randomly assigned into three groups 30 patients each; group Control received placebo, group Gabapentin received 600 mg of gabapentin and group Tropisetron received 5 mg tropisetron orally 2 hours before surgery. Frequency and severity of PONV, pruritus, pain severity, time to first request of rescue analgesic and incidence of side effects were recorded in the 1st 24 hours postoperative.

Incidence of PONV in Gabapentin and Tropisetron group decreased compared to Control group (p<0.05). Incidence of pruritus deceased in Gabapentin group compared to Control group (p = 0.03). Pain score in Gabapentin group was reduced at 2, 6, 12, 18 and 24 hours postoperative compared to Control group (P <0.05). The time to 1st request of rescue analgesia was prolonged in Gabapentin group compared to Control and Tropisetron group (P <0.05). There was no difference in the incidence of adverse effect in the three groups.

Prophylactic use of 600 mg of gabapentin or 5 mg tropisetron orally reduce the incidence of post operative nausea and vomiting induced by intrathecal morphine. Also gabapentin reduce the incidence of post operative itching and led to a decrease in postoperative analgesic requirement and pain scores