title: Use of patient-controlled analgesia with alfentanil for extracorporeal shock wave lithotripsy.
abstract: OBJECTIVE
  To compare the efficacy of patient-controlled analgesia (PCA) to physician-controlled analgesia in patients undergoing extracorporeal shock wave lithotripsy (ESWL).
  
  
  METHODS
  Prospective, randomized trial.
  
  
  METHODS
  New Jersey Kidney Stone Treatment Center at Robert Wood Johnson University Hospital, New Brunswick, NJ.
  
  
  METHODS
  62 ASA I, II, and III patients undergoing ESWL.
  
  
  METHODS
  The control group (n = 29) received physician-controlled analgesia with continuous infusions (0.75 mcg/kg/min) and intermittent boluses (5 mcg/kg) of alfentanil. PCA patients (n = 33) initially received alfentanil 0.5 mcg/kg followed by a continuous background infusion (0.2 to 0.5 mcg/kg/min) and self-administered alfentanil (3 to 5 mcg/kg) with a 5-minute lockout period. Bolus doses and infusion rates were determined by patient comfort and cardiorespiratory response to alfentanil.
  
  
  RESULTS
  Prior to the procedure, the patients completed two questionnaires (State-Trait Anxiety Inventory and Multidimensional Health Locus of Control Scales). During ESWL, blood pressure, heart rate, respiratory rate, oxygen saturation, end-tidal CO2, and pain and sedation levels were measured at 0, 800, 1,600, 2,400, and 3,000 shock waves. The total doses of alfentanil administered were calculated. PCA patients received 31% less alfentanil than control group patients (p < 0.0001). Patients with more preoperative anxiety required larger doses of alfentanil (p < 0.05). The pain level was slightly higher in the patients receiving PCA (p > 0.05) but most patients reported either no or only mild pain. Side effects from the therapy, such as nausea and vomiting, were either not present or were mild in both groups, with one patient (3% to 4%) in each group reporting mild nausea. Both patients and urologists were very satisfied with the pain management in both groups.
  
  
  CONCLUSIONS
  PCA is a useful alternative to physician-controlled analgesia during ESWL since it provides equivalent pain control while using less alfentanil.
authors.affiliation: Department of Anesthesia, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson School of Medicine, New Brunswick 08903-0019, USA.
authors.forename: H I
authors.initials: HI
authors.lastname: Kortis
authors.forename: D W
authors.initials: DW
authors.lastname: Amory
authors.forename: B K
authors.initials: BK
authors.lastname: Wagner
authors.forename: R
authors.initials: R
authors.lastname: Levin
authors.forename: E
authors.initials: E
authors.lastname: Wilson
authors.forename: A
authors.initials: A
authors.lastname: Levin
authors.forename: D E
authors.initials: DE
authors.lastname: Pitchford
authors.forename: P
authors.initials: P
authors.lastname: Pollak
mesh_terms: D000328:Adult; D015760:Alfentanil / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D008096:Lithotripsy; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012646:Self Administration; D011795:Surveys and Questionnaires
chemical_list: D015760:Alfentanil