The effect of a single dose of gabapentin on the rate of consumption of propofol and remifentanil during total intravenous anesthesia

Gabapentin (structural analog of GABA), is an antiepileptic drug that its preoperative administration results in postoperative pain reduction. Considering the hypnotic effect of propofol, which is mediated by its attachment to GABAA, this hypothesis was propounded that administration of gabapentin can probably decrease the need for propofol and remifentanil during total intravenous anesthesia. Fifty patients scheduled for elective laparoscopic cholecystectomy, were assigned into two equal groups (n=25) in this randomized double blinded clinical trial. Study group received oral gabapentin (1200mg), and control group received placebo 3hrs before operation. Premedication and induction of anesthesia were the same in all patients. For the maintenance of anesthesia, oxygen and nitrous oxide (50%-50% mixture) and propofol and remifentanil infusion were used. The rate of propofol infusion was adjusted to maintain BIS in the range of 40-60, and dose of remifentanil adjusted to maintain hemodynamic variables in the range of ±20% of baseline values. At the end of anesthesia the duration of anesthesia and the total amount of propofol and remifentanil used for every patient were recorded. The demographic parameters were similar in both groups (p>0.05). Doses of propofol and remifentanil used for study group were significantly lower than doses used for control group (p<0.01). The mean values of baseline systolic, diastolic, mean arterial, heart rates and BIS in the study group were lower than the corresponding values in the control group (p<0.05). This study showed that a single dose of gabapentin before operation can decrease the need for propofol and remifentanil in total intravenous anesthesia during laparoscopic cholecystectomy.