title: Safer colonoscopy with patient-controlled analgesia and sedation with propofol and alfentanil.
abstract: BACKGROUND
  The aim of this study was to assess the efficacy of patient-controlled analgesia and sedation with propofol/alfentanil for colonoscopy compared with continuous drug infusion and conventional nurse-administered medication.
  
  
  METHODS
  One hundred fifty patients undergoing colonoscopy on an outpatient basis were randomly assigned to 1 of 3 medication regimens. To maintain blinding, all patients were connected to an infusion pump. Group I patients could self-administer boluses of 4.8 mg propofol and 125 microg alfentanil without restriction. Group II patients received a continuous infusion with 0.048 mg/kg propofol and 0.12 microg/kg alfentanil per minute. Group III patients received intravenous premedication with 0.035 mg/kg midazolam and 0.35 mg/kg meperidine.
  
  
  RESULTS
  There were no differences between the groups with respect to pain (visual analogue scale) and procedure time. Patient-controlled analgesia and sedation with propofol/alfentanil (group I) resulted in less of an increase in the transcutaneous partial pressure of carbon dioxide (p = 0.0004) during colonoscopy and less of a decrease in mean arterial blood pressure (p = 0.0021) during recovery, as well as more complete recovery (p = 0.0019) after 45 minutes compared with conventional administration of midazolam/meperidine. Furthermore, patient-controlled analgesia and sedation yielded a higher degree of patient satisfaction than continuous infusion of propofol/alfentanil (p = 0.0033) or nurse-administered midazolam/meperidine (p = 0.0094).
  
  
  CONCLUSIONS
  Patient-controlled administration of propofol and alfentanil for colonoscopy may provide a better margin of safety than conventional administration of midazolam and meperidine and results in a higher level of patient satisfaction and shorter recovery.
authors: Division of Gastroenterology, Department of Internal Medicine, and the Institute of Anesthesiology, University Hospital of Zürich, Switzerland.
authors: D
authors: D
authors: Külling
authors: A C
authors: AC
authors: Fantin
authors: P
authors: P
authors: Biro
authors: P
authors: P
authors: Bauerfeind
authors: M
authors: M
authors: Fried
mesh_terms: D015760:Alfentanil; D016058:Analgesia, Patient-Controlled; D001794:Blood Pressure / Q000187:drug effects; D002245:Carbon Dioxide / Q000097:blood; D003113:Colonoscopy; D016292:Procedural Sedation; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008614:Meperidine; D008874:Midazolam; D008875:Middle Aged; D010147:Pain Measurement; D017060:Patient Satisfaction; D011292:Premedication; D015742:Propofol; D012449:Safety
chemical_list: D002245:Carbon Dioxide; D015760:Alfentanil; D008614:Meperidine; D008874:Midazolam; D015742:Propofol