MEASUREMENT OF PERITONEAL-FLUID HANDLING IN CHILDREN ON CONTINUOUS AMBULATORY PERITONEAL-DIALYSIS USING AUTOLOGOUS HEMOGLOBIN

Objective: Previous measurements of peritoneal fluid handling in child ren treated by continuous ambulatory peritoneal dialysis (CAPD) were p erformed with human albumin as a fluid marker. A major disadvantage of this substance is that endogenous patient albumin enters the peritone al cavity during the dwell period. For this reason peritoneal fluid ki netics were measured in a group of children on CAPD, using autologous hemoglobin as a volume marker. Design: Autologous hemoglobin was added to dialysate containing 1.36% glucose as a volume marker. Marker clea rance (MC), which is presently the best available approximation of lym phatic absorption in the clinical setting, and transcapillary ultrafil tration (TCUF) were measured during a 4-hour dwell. Setting: Universit y hospital. Patients: Children on CAPD (N=9), with a median age of 8.1 years (range 2.1-13.2 years). Results: MC was 521+/-166 mL/4 hour/1.7 3 M2, which is high compared to the literature data on adult CAPD pati ents. TCUF was 519+/-92 mL/4 hour/1.73 M2, which is similar to data co ncerning adult patients. TCUF reached no maximum during the 4-hour dwe ll, and the deviation of the TCUF curve from linear was markedly less than usually seen in adult patients. Conclusions: MC in children treat ed with CAPD is higher when compared to the literature data on adults. Difficulties to achieve sufficient ultrafiltration in children could be caused by relatively small differences between MC and TCUF from the beginning to the end of the dwell.