Clearance and recovery calculations in hemodialysis: Application to plasma, red blood cell, and dialysate measurements for cyclophosphamide

Publisher Website
Google Scholar
Abstract
The hemodialyzability of cyclophosphamide [an immunosuppressant and antineoplastic agent] was investigated in 4 patients on long-term hemodialysis. Cyclophosphamide [100 mg] was given i.v. over 10 min before hemodialysis. Blood and dialysate samples were collected periodically during the 4 h dialysis and measured by GLC for cyclophosphamide. Dialysis clearance calculated by arterial-venous difference and actual drug recovery in dialysate averaged 104 ml/min, which is in the range of the metabolic clearance of 95 ml/min for the drug. The extraction efficiency of the hollow-fiber dialyzers averaged 40% for plasma and red blood cell (RBC) samples. A mean of 37% of the administered dose of cyclophosphamide was removed during hemodialysis. The half-life (t1/2) of the beta phase was 3.3 h in these patients during hemodialysis, a 49% reduction of the 6.5 h t1/2 reported in uremic patients. Because of the reduction in elimination t1/2, larger dialysis clearance than metabolic clearance, high extraction efficiency and significant drug removal during dialysis, cyclophosphamide apparently is dialyzable.

This publication has 2 references indexed in Scilit: