['We evaluated the efficacy of intraarticular sufentanil in the prevention of postoperative pain after day-case arthroscopic procedures. Sixty patients were randomly assigned to receive either intraarticular sufentanil, 5 or 10 microg, and saline IV, or intraarticular saline and sufentanil 5 microg IV (control). All study medication was administered in a double-blinded fashion. Postoperatively and the day after surgery, pain levels at rest and during movement (i.e., active flexion of the knee), measured by a visual analog scale, were significantly lower in the Sufentanil groups compared with the Control group. Moreover, intraarticular sufentanil significantly reduced the postoperative consumption of analgesics. The time until discharge from the postanesthesia care unit (assessed by the Aldrete score) was significantly shorter in the patients receiving sufentanil intraarticularly. There were no significant differences between the two Sufentanil groups either in the intensity of postoperative pain or in discharge times from the postanesthesia care unit. We conclude that intraarticular sufentanil in arthroscopic knee procedures is a simple, effective, safe and well-tolerated analgesic technique for outpatients undergoing arthroscopic procedures. Increasing the dose sufentanil from 5 to 10 microg intraarticularly offered no additional advantage. Intraarticular sufentanil (5-10 microg) administration improves postoperative management after day-case diagnostic arthroscopic knee procedures.'] Does intraarticular sufentanil administration facilitate recovery after day-case knee arthroscopy?