Influence of remifentanil on Cp50 of propofol given by target-controlled fusion for loss of consciousness
- VernacularTitle:靶控输注瑞芬太尼或芬太尼对术前病人异丙酚镇静作用的影响
- Author:
Yun XUE
;
Xinmin WU
- Publication Type:Journal Article
- Keywords:
Propofol;
Piperidines;
Fentanyl;
Drug delivery systems;
Conscious sedation
- From:
Chinese Journal of Anesthesiology
1995;0(10):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective The aim of this prospective randomized study was to compare the effects of remifentanil (R) and fentanyl (F) given by target-controlled infusion (TCI) on the Cp50 of TCI propofol for loss of consciousness ( LOC ) . Methods Sixty-four ASA 1 or II patients aged 20-55 yr undergoing elective cholecystectomy or mastectomy under general anesthesia were enrolled in this study. Their BMI ranged from 18-30 kg?m-2. The patients were randomly allocated to one of four groups with 16 patients in each group: (1) propofol alone (P), (2) P + remifentanil (Cp = 4 ?g?L-1 ) (R4), (3) P + remifentanil (Cp = 7 ?g?L 1 ) (R7) and (4) P + fentanyl (Cp = 4?g?L-1 ) (F). The patients were unpremeditated. Anesthesia was induced with remifentanil or fentanyl and propofol both given by TCI. The plasma concentration (Cp) of remifentanil and fentanyl were fixed in each group. The Cp50 of propofol for LOC was determined by up-and-down sequential trial. Cp of propofol was set at 1.25, 1.50, 1.80, 2.16, 2.59, 3.11, 3.73 and 4.48 mg?L-1 . If a patient did not go to sleep at a certain Cp of propofol, the next patient was tested at a higher concentration conversely if the patient went to sleep a lower concentration was tested in the next patient. The BIS values and hemodynamic changes were recorded before induction and at LOC (no response to verbal command and loss of eyelash reflex). The TCI pump was controlled by pharmacokinetic models developed by Marsh (propofol) Minto ( remifentanil) and Shafer ( fentanyl) . Results The Cp of propofol for LOC in group P was 3.48 mg ? L-1 , significandy higher than that in group F (2.31 mg ? L -1 ), group R4 (2.11 mg?L-1) and group R7 (1.76mg?L-1 ) (P
