THE PERITONEAL EQUILIBRATION TEST IN CHILDREN

Eight children, aged 15 months to 17 years 9 months, maintained by con tinuous ambulatory peritoneal dialysis (CAPD)/continuous cycling perit oneal dialysis and nine adults, aged 20-59 years, managed by CAPD were compared using a standardized peritoneal dialysis protocol, the perit oneal equilibration test (PET). The peritoneal glucose concentration t ended to equilibrate with the serum glucose more rapidly in children, but the percentage of the glucose load absorbed was not different betw een the two age groups. There was an inverse trend between the percent age of glucose absorbed and age in children. Peritoneal creatinine cle arance scaled to surface area in children was significantly less than that of the adults; however, the clearances became similar when adjust ed for body weight. Peritoneal creatinine clearance scaled to surface area bore a positive and significant relationship to age which, when e xpressed per kilogram body weight, disappeared. Children had a signifi cantly higher dialysate/plasma (D/P) creatinine ratio after the first 2 h of the PET, but this ratio approached unity by 4 h and was not dif ferent from adults. The fractional change in the creatinine D/P ratio during the PET was not different between the two age groups. Drain vol ume adjusted to surface area was significantly less in children than a dults. This difference was reversed when drain volume was factored by weight. Similarly drain volume scaled to surface area demonstrated a s ignificant and positive relationship to age, which disappeared when dr ain volume was expressed per kilogram body weight. Ultrafiltration, wh ether factored by weight or scaled to surface area, did not differ bet ween the two groups. The post-PET residual volume corrected for body w eight was significantly larger in the children, but bore no relationsh ip to age. It is possible that this larger residual volume in children functions as a tidal volume enhancing solute equilibration.