The pharmacokinetics of intravenously adminstrered lidocaine were studied in 5 normal patients withno renal disease and 4 patients with end-stage renal failue during anesthesia. In both group of patinets, the half life, the volume of distribution and clearance were not significantly different. However, valuses were altered in comparison with those of subjuc without anesthesia. This alteration of parameters is thought to be the effect of reduced hepatic blood flow due to potent anestheics grugs. Our understanding of lidocaine pharmacokinetics in patients with chronic renal failure during anesthesia suggests that these patients can safely receive a normal loading and maintenanece dose with close monitoring for signs of lidocaine toxicity. even though the total plasma concentration may be within the therapeutic range.