Secondary Logo

Journal Logo

Effect of clonidine on propofol and remifentanil TCI titrated as a function of PRST score, BIS, and the A-line ARX index (AAI) in morbidly obese patients during laparoscopic gastric by-pass


Langlet, E.; Nkiko, G.; Lauwick, S.; Kaba, A.; Joris, J.

European Journal of Anaesthesiology (EJA): June 12th, 2010 - Volume 27 - Issue 47 - p 154

Department of Anaesthesiology and Intensive Care, CHU Liège, University of Liège, Liège, Belgium

Background and Goal of Study: Intravenous clonidine reduces intraoperative requirements of anaesthetic agents, which is particularly welcome in morbidly obese patients. Mechanisms of this sparing effects remain controversial : haemodynamic control vs. direct anaesthetic effect.1We investigated the effects of clonidine on propofol (PROP) and remifentanil (REMI) requirements in morbidly obese patients during laparoscopic gastric by-pass (LGBP) using PRST score, BIS, and A-line ARX index (AAI)2.

Materials and Methods: After IRB approval and informed consent 34 morbidly obese patients scheduled for LGBP were included in this study. Anaesthesia consisted of PROP and REMI TCI. Before the induction of anaesthesia patients were randomly allocated in two groups: Clonidine 4 g/kg of IBW in 10 min then 2 g/kg/h during 1 h or Saline. PROP is titrated to keep BIS around 50, and REMI to maintain PRST < 3 and AAI < 30. PRST, BIS, AAI, and the effect site concentrations of PROP and REMI were recorded at skin incision (T1), enteroenteral anastomosis (T2), gastric stapling (T3), gastro-intestinal anastomosis (T4). Data (mean ± SD) were analyzed using ANOVA. P<0.05 = statistically different.

Results and Discussion: Demographic data, PRST scores, BIS, AAI, and haemodynamics were similar in both groups. Effect site concentrations of PROP [table 1] and REMI [table 2] were significantly less in clonidine group (respectively P=0.029 et P=0.05).

Table 1

Table 1

Table 2

Table 2

Conclusion(s): This study demonstrate that Clonidine decreases PROP and REMI requirements by a hypnotic and analgesic effects. These sparing effects are independent on haemodynamic properties of clonidine.

Back to Top | Article Outline


1 Wallace A. Curr Opinion Anaesthesiol 2006; 19:411-17.
    2 Bonhomme V. et coll., BJA 2006; 96:353-60.
      © 2010 European Society of Anaesthesiology