Premedication with sublingual buprenorphine for out-patient arthroscopy: reduced need for postoperative pethidine but higher incidence of nausea.

The effect of preoperative sublingual buprenorphine (B) on postoperative pain (VAS), the need for postoperative opioid injections and on time to discharge, was evaluated in a prospective randomised double-blind study. Forty ASA I-II patients scheduled for arthroscopy of the knee received premedication with 0.4 mg buprenorphine (group B) and 42 patients were given placebo (group P). Postoperatively, pethidine was given to patients with pain. Three of the 40 patients in group B vs 11 of the 42 in group P received pethidine (P < 0.05). In group B, however, 13 of the 40 patients complained of nausea, prolonging median time to discharge from 155 to 255 minutes (P < 0.05). In group P, 3 of the 42 patients were nauseated, P < 0.01, compared with group B. Time to discharge did not differ between the groups in patients without nausea. The median respiratory rate was significantly lower in group B, but no patient required ventilatory support. In conclusion, premedication with sublingual buprenorphine cannot be recommended for this procedure. It reduces the need for postoperative injections of pethidine but increases the incidence of postoperative nausea which prolongs the recovery time. Careful monitoring is also mandatory because of the possibility of respiratory depression.