Comparison of intravenous sedative-analgesic techniques for outpatient immersion lithotripsy.

Fifty-three unpremedicated outpatients undergoing elective extracorporeal shock wave lithotripsy using an unmodified Dornier HM-3 lithotriptor received one of two different intravenous sedation-analgesia techniques. Both intravenous midazolam-alfentanil and fentanyl-propofol techniques produced conditions comparable to those achieved with epidural anesthesia during immersion lithotripsy. Of the two sedative-analgesic techniques, midazolam-alfentanil was associated with greater intraoperative amnesia (81% vs 38%), whereas fentanyl-propofol produced less cardiorespiratory depression and fewer postoperative side effects (e.g., pruritus). Compared with a standard epidural anesthesia technique, the mean anesthesia and recovery times were significantly shorter with the two intravenous sedation-analgesia techniques (57-62 min vs 105 min and 143-147 min vs 199 min, respectively). These data suggest that combinations of either midazolam and alfentanil or fentanyl and propofol are viable alternatives to epidural anesthesia for outpatient immersion lithotripsy.