Objective: Measurement of mass transfer area coefficients (MTAC) in children of different sizes to determine if solute transport varies with age and to compare with published adult values.
Design: Mass transfer area coefficients calculated from prospectively collected data in 28 selected patients.
Participants: All children starting maintenance peritoneal dialysis at the Hospital for Sick Children. Selected patients were also studied if hospitalized for unrelated reasons.
Results: Mean MTAC values for creatinine and glucose were 4.0 and 4.5 mL/min, respectively, both considerably lower than adult values. When scaled per 70 kg body weight, these results were greater, and when scaled per 1.73 m2 surface area, they were lower than reported adult values. The MTAC/kg body weight was inversely correlated to age.
Conclusions: Solute transport in children is directly related to age and does not approach adult values until later childhood. However, more rapid transport per unit body weight is observed in children and may reflect an increased effective peritoneal surface area.