Pharmacokinetics of sufentanil in patients undergoing renal transplantation

Renal failure and chronic haemodialysis are often associated with alterations in fluid status and plasma proteins. These changes, in turn, may result in pharmacokinetic alterations in affected patients. The purpose of this study was to investigate the pharmacokinetics of sufentanil in chronic renal failure patients undergoing kidney transplantation. Ten male patients were studied. Following induction of anaesthesia each patient received sufentanil 2.0 micrograms.kg-1 IV with subsequent serial plasma sampling for drug measurement from one to 360 minutes. A biexponential equation provided the best fit of the sufentanil concentration data with mean +/- SEM distribution (alpha) and elimination (beta) half-lives of 2.9 +/- 1.3 and 176 +/- 87 minutes, respectively. The mean Vc and Vd beta values were 0.15 +/- 0.05 L.kg-1 and 0.85 +/- 0.16 L.kg-1, respectively; plasma drug clearance was 11.5 +/- 3.7 ml.kg-1.min-1. Mean values for K10, K12 and K21 were 0.15 +/- 0.06.min-1, 0.4 +/- 0.14.min-1 and 0.1 +/- 0.04.min-1, respectively. With the exception of Vd beta, these pharmacokinetic values are similar to those reported in previous studies in general surgical, elderly and burn patients. The Vd beta values observed in this study may have resulted from alterations in drug distribution or elimination following revascularization of the implanted kidneys. Nevertheless, it appears that modification of sufentanil doses is unnecessary in chronic renal failure patients undergoing renal transplantation.