[The pharmacokinetics of cisplatin and its influence on renal functions based on different infusion methods]

The pharmacokinetics of cisplatin, together with its renal toxicity in relation to different infusion methods were examined. The subjects were 21 in-patients suffering from pulmonary carcinoma treated by anti-neoplastic agents including cisplatin. The patients included 12 given a 5-division dosage, 5 cases given 24-hour continuous infusion, 6 given 12-hour continuous infusion, and 7 given 6-hour continuous infusion. Cisplatin was determined as the concentrations of Pt in plasma and non-protein-bound Pt. Also, as indices of renal function, NAG in urine together with beta 2-microglobulin were examined. No substantial difference could be found in Pt concentration in plasma upon completion of the respective infusion methods. A dual-phase attenuation curve was obtained after the completion of infusion and the half-life period of the beta-phase was around 200 hours. With respect to non-protein-bound Pt concentrations, the 5-division dosage showed the highest value, which was considered to be a temporary phenomenon, while with continuous infusion, the shorter the infusion period, the higher the value became. With respect to the amount of NAG excreted in urine, 12-and 6-hour continuous infusion showed the higher value in comparison with the others in terms of the maximum value and the total amount. With regard to beta 2-microglobulin, 6-hour continuous infusion showed the highest value. The above results therefore suggest that in continuous infusion, the shorter the infusion period the greater the degree of renal tubule injury, and that particularly, 6-hour continuous infusion will possibly cause dysfunction of the renal tubules.