title: Intravenous droperidol causes a reduction in the bispectral index in propofol-sedated patients during spinal anesthesia.
abstract: We investigated the effect of IV droperidol on the bispectral index (BIS) in conscious and propofol-sedated patients during spinal anesthesia. Thirty minutes after the induction of spinal anesthesia, 20 patients were given 2 mg of droperidol IV without administration of other sedatives (conscious group). Another group of patients were sedated with a propofol infusion to maintain BIS at 60 +/- 5 and were administered IV saline (placebo group; n = 20), droperidol 1 mg (dro-1 group; n = 20), or droperidol 2 mg (dro-2 group; n = 20) in a randomized order and in a double-blinded fashion. Although BIS remained the same in the conscious and placebo groups, it significantly decreased after administration of droperidol in the dro-1 and dro-2 groups. The decrease in BIS was significantly larger in the dro-2 group than in the dro-1 group. These results suggest that an antiemetic dose of droperidol enhances the hypnotic effect of propofol in a dose-dependent manner during spinal anesthesia.
  
  
  CONCLUSIONS
  An antiemetic dose of IV droperidol causes a decrease in the bispectral index in patients sedated with propofol during spinal anesthesia. We conclude that droperidol may enhance the hypnotic effect of propofol.
authors.affiliation: *Department of Anesthesiology, Sapporo Medical University School of Medicine; and †Division of Anesthesia, Obihiro Kosei Hospital, Japan.
authors.forename: Masayasu
authors.initials: M
authors.lastname: Nakayama
authors.forename: Noriaki
authors.initials: N
authors.lastname: Kanaya
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Ichinose
authors.forename: Shuji
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Namiki
mesh_terms: D000328:Adult; D000762:Anesthesia Recovery Period; D000775:Anesthesia, Spinal; D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D016292:Procedural Sedation; D004311:Double-Blind Method; D004329:Droperidol / Q000008:administration & dosage / Q000494:pharmacology*; D004569:Electroencephalography / Q000187:drug effects*; D005260:Female; D013509:Gynecologic Surgical Procedures; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006993:Hypnotics and Sedatives; D008875:Middle Aged; D015742:Propofol
chemical_list: D014150:Antipsychotic Agents; D006993:Hypnotics and Sedatives; D004329:Droperidol; D015742:Propofol