Oral slow release dextromethorphan premedication provides a pethidine spare effect on posthemorrhoidectomy pain...

In our previous study, we had demonstrated that intramuscular (i.m.) dextromethorphan (DM) could provide a preemptive analgesic effect and improve postoperative pain management. Regrow is a long-duration slow-release oral dextromethorphan available for clinical use with good patient compliance. The present study was designed to examine whether oral regrow may also offer the same preemptive analgesic effect as i.m. DM does in postoperative pain management.

Seventy-five patients, ASA status I and II, scheduled for hemorrhoidectomy were included and randomly assigned to the control and study groups. In the control group patients received placebo orally 8 h before surgical incision. In the study group, patients received regrow orally either 120 mg (R-120) or 240 mg (R-240) 8 h before skin incision. Pethidine (1 mg/kg, i.m.) was given for postoperative pain relief on demand. The time to first pethidine injection, total pethidine consumption, worst pain score, and pethidine-related side effects were recorded for two days.

The times to first pethidine injection were 5.4 +/- 3.1, 6.5 +/- 3.5 and 12.7 +/- 5.7 h in the control, R-120 and R-240 groups, respectively. Total pethidine consumptions were 150 +/- 12, 132 +/- 11.8 and 82 +/- 12.5 mg in the control, R-120 and R-240 groups, respectively. The worst visual analog scale pain scores were respectively 7.2 +/- 0.4, 6.9 +/- 0.2 and 5.5 +/- 0.4 in the control, R-120 and R-240 groups during the 2-day observation. Five and three patients suffered pethidine-related side effects in the control and R-120 groups, respectively.

This study revealed that premedication of oral regrow 240 mg provided a preemptive analgesic effect, thus reducing the severity of postoperative pain and pethidine requirement in post-hemorrhoidectomy patients.