title: Use of alfentanil for in vitro fertilization oocyte retrieval.
abstract: OBJECTIVE
  To determine alfentanil levels with a specific radioimmunoassay in serum and ovarian follicular fluid.
  
  
  METHODS
  Observational study.
  
  
  METHODS
  University hospital.
  
  
  METHODS
  14 ASA status I women undergoing oocyte retrieval for in vitro fertilization.
  
  
  METHODS
  General anesthesia was induced with alfentanil 15 micrograms/kg and midazolam 2 mg and maintained with alfentanil 0.5 mg, 60% nitrous oxide (N2O) in oxygen (O2) and midazolam up to a total of 4 mg. Oocyte retrieval was performed using a transvaginal ultrasound guided technique, 34 to 36 hours after human chorionic gonadotrophin administration.
  
  
  RESULTS
  Mean procedure time for oocyte retrieval was 18 +/- 2.4 (SEM) minutes. All patients were fully awake within 5 minutes and all patients except one were able to move from the operating table to the stretcher with minimal help. Mean total protein concentration in the follicular fluid was 3.8 +/- 0.4 mg%. Maximal serum alfentanil concentrations (Cmax) were attained 5 minutes after start of the procedure (tmax) and were 92 +/- 20 ng/ml. In contrast, alfentanil concentrations in the follicular fluid increased constantly throughout the procedure up to 8.9 +/- 0.8 ng/ml at 15 minutes. Clinical pregnancy rate was 3 of 14 patients.
  
  
  CONCLUSIONS
  It is evident that during the oocyte retrieval procedure, the alfentanil concentrations in the follicular fluid are about ten-fold smaller than the serum alfentanil concentrations at the same time points. Similar pharmacokinetics have been shown when propofol was used as anesthetic. The low accumulation of alfentanil in the follicular fluid increases the attractiveness of alfentanil for anesthesia during oocyte retrieval for in vitro fertilization.
authors.affiliation: Department of Anesthesiology and Critical Care Medicine, Hadassah University Hospital, Jerusalem, Israel.
authors.forename: S C
authors.initials: SC
authors.lastname: Shapira
authors.forename: S
authors.initials: S
authors.lastname: Chrubasik
authors.forename: A
authors.initials: A
authors.lastname: Hoffmann
authors.forename: N
authors.initials: N
authors.lastname: Laufer
authors.forename: A
authors.initials: A
authors.lastname: Lewin
authors.forename: F
authors.initials: F
authors.lastname: Magora
mesh_terms: D000328:Adult; D015760:Alfentanil / Q000097:blood / Q000493:pharmacokinetics; D000768:Anesthesia, General; D018686:Anesthetics, Intravenous / Q000097:blood / Q000493:pharmacokinetics; D001794:Blood Pressure / Q000187:drug effects; D005260:Female; D005307:Fertilization in Vitro; D015571:Follicular Fluid / Q000378:metabolism; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D009865:Oocytes; D011863:Radioimmunoassay
chemical_list: D018686:Anesthetics, Intravenous; D015760:Alfentanil