PATIENT-CONTROLLED SEDATION AND ANALGESIA DURING SWL

Sixty unpremedicated outpatients undergoing elective extracorporeal sh ockwave lithotripsy (SWL) using a Dornier MPL 9000 lithotripter were r andomly assigned to receive either propofol-alfentanil (PA group; N = 30) or midazolam-alfentanil (MA group; N = 30) by a patient-controlled analgesia (PCA) device for sedation and analgesia, Although pain inte nsity scores were lower after 20 minutes and sedation was more pronoun ced in the MA group, both drug regimens produced satisfactory sedation and analgesia and allowed the maximum number of shockwaves to be give n, Alfentanil consumption was less in the MA group (P < 0.05), Both gr oups were hemodynamically stable, The patients in the MA group had slo wer ventilation rates, lower oxygen saturation, and higher end-tidal c arbon dioxide levels, Use of MA was associated with more episodes of o xygen desaturation to < 90% (30% vs, 11%; P < 0.05). One patient in th e PA group and three patients in the MA group developed bradypnea (<10 breaths/min), Patient satisfaction was very high with the two sedativ e-analgesic techniques, Propofol and midazolam, when given in combinat ion with alfentanil using a PCA pump, may provide safe, effective anal gesia and sedation during lithotripsy. Patient-controlled sedation and analgesia may provide optimal conditions for SWL of urinary tract sto nes and is a useful alternative to other forms of anesthesia and analg esia.