Changes in Peritoneal Equilibration Test Values during Long-Term Peritoneal Dialysis in Peritonitis-Free Children

Little is known about the changes in peritoneal equilibration test (PET) values in children on long-term peritoneal dialysis (PD). In the present study, a PET was carried out every 6 months in 39 children (mean age 8.8 ± 5.5 years) undergoing PD for 6 to 85 months (mean 36.9 ± 23.1 months). Patients experiencing peritonitis were excluded. Both D/P creatinine (dialysate-to-plasma ratio of creatinine at 4 hours) and D/D0glucose (ratio of dialysate glucose at 4 hours’ dwell time to dialysis glucose at 0 dwell time) were measured 195 times in this series of patients. No remarkable change was found for D/P creatinine or D/D0glucose during the first 24 months of PD but thereafter, D/P creatinine increased gradually and D/D0glucose decreased gradually. Mean D/P creatinine increased significantly after the first 24 months of PD: from 0.66 ± 0.12 during the first 24 months, to 0.70 ± 0.09 after 25 months and more of PD ( p = 0.0051). Mean D/D0glucose decreased significantly after 24 months of PD: from 0.42 ± 0.09 during the first 24 months, to 0.38 ± 0.08 after 25 months and more of PD ( p = 0.0015). The most significant change for both D/P creatinine and D/D0glucose occurred after 24 months of PD. It seems reasonable to consider the mean PET values at 24 months of PD as the standard PET values.

Peritoneal Dialysis Prescription for Neonates

Despite the major advances in the management of renal failure, the mortality and morbidity rates remain higher in neonates than in older children. But, in most of the cases, effective peritoneal dialysis is possible, giving these neonates a chance of life. In infants and neonates, peritoneal permeability seems to be in a hyperpermeable state, perhaps only related to the volume of the instilled dialysate. Practical peritoneal prescriptions in neonates have to be balanced between either short dwell times optimizing ultrafiltration or long dwell times optimizing the diffusive process and blood purification. The recommendations for peritoneal dialysis in neonates usually admitted are short dwell times, one hour or less, adapted to ultrafiltration need, and small instilled dialysate volumes, 10 20 mL/kg initially, to avoid raised intra-abdominal pressure. Age-related particular risks are hyponatremia and hypophosphatemia.

Standard peritoneal permeability analysis in children

Peritoneal transport characteristics in children on peritoneal dialysis (PD) has been reported to be different compared to adults. However, various test methods can influence this difference. Thirty-one standard peritoneal permeability analyses (SPA) were performed in 18 PD children with a median (range) age of 9.8 yr (2 to 19) and a median duration of PD of 2.6 yr (0.19 to 6.8). The median mass transfer area coefficient (MTAC) for creatinine was 9.6 ml/min per 1.73 m(2) (4.4 to 18.0), and for urea 17.3 ml/min per 1. 73 m(2) (12.2 to 22.8). The median dialysate to plasma creatinine ratio (D/P(Cr)) was 0.69 (0.44 to 0.92), the glucose absorption 59% (23 to 75), and the D/D(0) for glucose 0.38 (0.23 to 0.62). The median clearance of beta(2)-microglobulin was 923 microl/min per 1. 73 m(2) (366 to 1828), of albumin 103 microl/min per 1.73 m(2) (55 to 211), of IgG 48 microl/min per 1.73 m(2) (20 to 105), and of alpha(2)-macroglobulin 12 microl/min per 1.73 m(2) (5 to 49). No correlation was found between these results and age or PD time. The restriction coefficient for macromolecules indeed increased with duration of PD treatment (r = 0.38, P = 0.03). The median transcapillary ultrafiltration rate was 1.2 ml/min per 1.73 m(2) (-0. 01 to 2.8), the net ultrafiltration rate 0.2 ml/min per 1.73 m(2) (-1.97 to 1.82), and the effective lymphatic absorption rate 1.04 ml/min per 1.73 m(2) (-0.06 to 2.91). When corrected for body surface area, no differences were found in peritoneal fluid and solute transport characteristics between children and adults. No effect of time on PD on the transport parameters was found in a cross-sectional analysis, except for an increase of the restriction coefficient to macromolecules. This finding is similar to observations in adults. Therefore, the present study showed no evidence for the common belief that the peritoneal membrane in children is different from that in adult patients.