Pilot study on the effect of tourniquet use on sufentanil pharmacokinetics.
OBJECTIVE
To test our hypothesis that sequestration of sufentanil can occur during surgery when a pneumatic tourniquet is used.


METHODS
Prospective, randomized study.


METHODS
Operating room and recovery room of a university hospital.


METHODS
16 ASA physical status I and II patients scheduled for orthopedic surgery with pneumatic tourniquet use.


METHODS
Patients were randomized to three groups. Sufentanil was given intravenously at 0.5 microg kg(-1) bolus at the same time that a constant infusion was started at 0.5 microg kg h(-1). In Group 1, continuous infusion of sufentanil was stopped when the tourniquet was released (n = 6). In Group 2, continuous infusion of sufentanil was stopped 15 minutes after tourniquet release (n = 6). In Group 3, as a control group, the sufentanil bolus was started after tourniquet inflation (n = 4).


METHODS
Plasma sufentanil concentrations were determined by radioimmunoassay. To compare pharmacokinetic results, a simulation of the sufentanil plasma concentrations was achieved.


RESULTS
Exsanguination and inflation of the pneumatic tourniquet had no significant effect on pharmacokinetic results. In 75% of patients, a significant increase in sufentanil plasma concentration occurred between 30 and 60 minutes after tourniquet deflation in all three groups, probably as a result of patient mobilization. One respiratory distress event occurred in a Group 2 patient following extubation at 55 minutes after the end of the sufentanil infusion. The rebound of sufentanil concentration was higher in Group 2; it may be due to a reduced effect of the restoring circulation in the ischemic leg by a prolonged infusion after tourniquet deflation.


CONCLUSIONS
Using a pneumatic tourniquet induces transient changes in the pharmacokinetics of sufentanil. These changes may have clinical relevance during the first hour after tourniquet release.
Estebe
J P
JP
Service d'Anesthésie-Réanimation Chirurgicale 2, Centre Hospitalier Régional et Universitaire, Rennes, France.
Le Corre
P
P
Levron
J C
JC
Le Moing
J P
JP
Le Naoures
A
A
Ecoffey
C
C
D000328:Adult; D018686:Anesthetics, Intravenous / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D010865:Pilot Projects; D011446:Prospective Studies; D011863:Radioimmunoassay; D017409:Sufentanil / Q000493:pharmacokinetics*; D014111:Tourniquets
D018686:Anesthetics, Intravenous; D017409:Sufentanil