title: Patient-controlled drug administration during local anesthesia: a comparison of midazolam, propofol, and alfentanil.
abstract: OBJECTIVE
  To evaluate the perioperative effects of alfentanil, midazolam, and propofol when administered using a patient-controlled analgesia (PCA) device during local anesthesia.
  
  
  METHODS
  Randomized, single-blind comparative study.
  
  
  METHODS
  Outpatient surgery center at a university teaching hospital.
  
  
  METHODS
  Ninety outpatients undergoing minor elective surgical procedures with local anesthetic infiltration were assigned to one of three treatment groups.
  
  
  METHODS
  After premedication with midazolam 1 mg intravenously (IV) and fentanyl 50 micrograms IV, patients were allowed to self-administer 2 ml bolus doses of either alfentanil 250 micrograms/ml, midazolam 0.4 mg/ml, or propofol 10 mg/ml at minimal intervals of 3 minutes to supplement a basal infusion rate of 5 ml/hr.
  
  
  RESULTS
  The total intraoperative dosages of alfentanil, midazolam, and propofol were 2.7 +/- 1.1 mg, 4.7 +/- 2.7 mg, and 114 +/- 42 mg, respectively, for procedures lasting 48 +/- 28 minutes to 51 +/- 19 minutes (means +/- SD). Propofol produced more pain on injection (39% vs. 4% and 6% in the alfentanil and midazolam groups, respectively). Episodes of arterial oxygen saturation less than 90% were more frequent with alfentanil (28%) than with midazolam (3%) or propofol (13%). Using the visual analog scale, patients reported comparable levels of discomfort, anxiety, and sedation during the operation in all three treatment groups. Postoperative picture recall was significantly decreased with midazolam versus alfentanil and propofol. Finally, postoperative nausea was reported more frequently in the alfentanil group (29%) than in the midazolam (10%) or propofol (18%) groups, contributing to a significant prolongation of the discharge time in the alfentanil-treated patients.
  
  
  CONCLUSIONS
  When self-administered as adjuvants during local anesthesia using a PCA delivery system, alfentanil, midazolam, and propofol were equally acceptable to patients. However, propofol and midazolam were associated with fewer perioperative complications than was alfentanil.
authors.affiliation: Department of Anesthesiology and Pain Management, University of Texas, Southwestern Medical Center, Dallas 75235-9068.
authors.forename: A F
authors.initials: AF
authors.lastname: Ghouri
authors.forename: E
authors.initials: E
authors.lastname: Taylor
authors.forename: P F
authors.initials: PF
authors.lastname: White
mesh_terms: D000328:Adult; D000368:Aged; D015760:Alfentanil / Q000008:administration & dosage*; D000556:Ambulatory Surgical Procedures; D016058:Analgesia, Patient-Controlled / Q000295:instrumentation*; D000772:Anesthesia, Local / Q000295:instrumentation*; D005260:Female; D006801:Humans; D008297:Male; D008874:Midazolam / Q000008:administration & dosage*; D008875:Middle Aged; D015742:Propofol / Q000008:administration & dosage*; D016037:Single-Blind Method
chemical_list: D015760:Alfentanil; D008874:Midazolam; D015742:Propofol