CAPILLARY BLOOD VERSUS ARTERIAL OR VENOUS-BLOOD FOR TACROLIMUS MONITORING IN LIVER-TRANSPLANTATION

Tacrolimus has been found to be useful in clinical solid organ transpl antation, A very careful monitoring of the tacrolimus levels and dose adjustments are essential, at least in the immediate post-liver transp lantation situation. However, quite often after liver transplantation, patients have limited venous access for daily monitoring of tacrolimu s levels, When the blood is sampled from a multilumen central venous c atheter, used also for intravenous administration of tacrolimus, false ly elevated concentrations of tacrolimus have been observed, The prese nt study examines the concentration of tacrolimus in capillary blood s amples obtained from finger stick and compares its concentrations in s imultaneously drawn samples from arterial line, peripheral venous punc ture, and multilumen centrally placed venous catheter from the port us ed for tacrolimus infusion and the port not used for tacrolimus infusi on, Ten adult post-liver transplantation recipients were studied. Whol e blood concentration of tacrolimus in capillary blood was comparable to that of arterial blood, as well as to that of peripheral venous blo od samples (r(2) = 0.99; P = 0.72). Concentrations of tacrolimus in ve nous blood drawn from the port of the multilumen catheter used for int ravenous tacrolimus infusion were 3-23 times higher (P = 0.0015), whil e the concentrations of venous blood drawn from the port not used for tacrolimus infusion were 1.7-4.5 times higher (P = 0.016), as compared with arterial, capillary, or peripheral venous whole blood concentrat ions.