title: Patient-controlled analgesia with alfentanil for outpatient lithotripsy.
authors.forename: J
authors.initials: J
authors.lastname: Mackenzie
mesh_terms: D015760:Alfentanil; D000556:Ambulatory Surgical Procedures; D016058:Analgesia, Patient-Controlled; D006801:Humans; D007669:Kidney Calculi / Q000628:therapy; D008096:Lithotripsy
chemical_list: D015760:Alfentanil