ABSTRACT
INTRODUCTION: Growth retardation is a common problem in pediatric patients with chronic kidney disease. It is unknown if the growth of children on peritoneal dialysis (PD) can be augmented by more dialysis. METHODS: We studied the effect of various peritoneal adequacy parameters on delta height standard deviation scores (SDSs) and growth velocity z-scores in 53 children (27 males) on PD, who underwent 2 longitudinal adequacy tests at 9-month intervals. None of the patients were on growth hormone. Intraperitoneal pressure and standard KDOQI guidelines were compared to the outcome measures delta height SDS and height velocity z-scores, using univariate and multivariate tests. RESULTS: At the time of the second PD adequacy test, their mean age was 9.2 ± 5.3 years; mean fill volume was 961 ± 254 mL/m2; and median total infused dialysate volume was 5.26 L/m2/day (range 2.03-15.32 L). The median total weekly Kt/V was 3.79 (range 0.9-9.5), and the median total creatinine clearance was 56.6 (range 7.6-133.48) L/week, higher than previous pediatric studies. The delta height SDS was a median of -0.12 (range -2 to +3.95)/year. The mean height velocity z-score was -1.6 ± 4.0. The only relationships discovered were between the delta height SDS and age, bicarbonate, and intraperitoneal pressure, but not for Kt/V or creatinine clearance. CONCLUSION: Our findings highlight the importance of normalization of bicarbonate concentrations to improve height z-score.
ABSTRACT
Peritoneal equilibration test (PET) is the gold standard for evaluating peritoneal transport, and measurement of the drain volume after 4-h dwell time with glucose 4.25% is a simple means of evaluating failure of ultrafiltration. The study objective was to verify if the measurement of the volume drained after 4 h dwell of icodextrin at 7.5% (ICO), has a better correlation with the parameters of PET. Patients in a peritoneal dialysis program (N = 35) underwent three procedures: PET; determination of the drain volume after a 4-h dwell with glucose 4.25%; and determination of the drain volume after a 4-h dwell with ICO. Among patients who were classified as high transporters, the ultrafiltration volume was greater after ICO use. The ICO ultrafiltration volume correlated negatively with the ratio between the 4- and 0-h dialysate glucose concentrations (D4/D0 ratio, r = -0.579; P = 0.002), correlating positively with the dialysate-to-plasma ratio for creatinine (D/PCr ratio, r = 0.474; P = 0.002). For ICO, the area under the receiver operating characteristic curve was 0.867 and 0.792 for the D/PCr and D4/D0 ratios (P < 0.0001 and P = 0.004, respectively), compared with 0.738 and 0.710 for glucose 4.25% (P = 0.020 and P = 0.041, respectively). A cut-off volume of 141 mL discriminated high/high-average transporters from low/low-average transporters. Volume drained after ICO use better predicts peritoneal transport patterns than does that drained after the use of glucose 4.25%.
Subject(s)
Dialysis Solutions/pharmacokinetics , Icodextrin/pharmacokinetics , Peritoneal Dialysis , Peritoneum/physiology , Cross-Sectional Studies , Female , Humans , Male , Middle AgedABSTRACT
The peritoneal equilibration test (PET) is the most widespread method for assessing water and solute transport across the peritoneal membrane. This study compared three methods: traditional PET (t-PET), mini-PET, and modified PET (mod-PET). Non-diabetic adults (n=21) who had been on peritoneal dialysis (PD) for at least three months underwent t-PET (glucose 2.5%-4 h), mini-PET (glucose 3.86%-1 h), and mod-PET (glucose 3.86%-4 h) to determine dialysate-to-plasma concentration ratio (D/P) for creatinine and dialysate-to-baseline dialysate concentration ratio (D/D0) for glucose. Agreement between methods regarding D/P creatinine and D/D0 glucose was assessed using analysis of variance (ANOVA), Pearson's correlation coefficient, and Bland-Altman analysis. D/P creatinine differed between t-PET and mini-PET (P<0.001) and between mod-PET and mini-PET (P<0.01) but not between t-PET and mod-PET (P=0.746). The correlation of D/P creatinine with t-PET vs mod-PET was significant (r=0.387, P=0.009) but not that of t-PET vs mini-PET (r=0.088, P=0.241). Estimated bias was −0.029 (P=0.201) between t-PET and mod-PET, and 0.206 (P<0.001) between t-PET and mini-PET. D/D0 glucose differed between t-PET and mod-PET (P=0.003) and between mod-PET and mini-PET (P=0.002) but not between t-PET and mini-PET (P=0.885). The correlations of D/D0 glucose in t-PET vs mod-PET (r=−0.017, P=0.421) or t-PET vs mini-PET (r=0.152, P=0.609) were not significant. Estimated bias was 0.122 (P=0.026) between t-PET and mod-PET, and 0.122 (P=0.026) between t-PET and mini-PET. The significant correlation of D/P creatinine between t-PET and mod-PET suggested that the latter is a good alternative to t-PET. There was no such correlation between t-PET and mini-PET.
Subject(s)
Humans , Male , Female , Middle Aged , Peritoneal Dialysis/methods , Kidney Failure, Chronic/therapy , Peritoneum/metabolism , Biological Transport , Creatinine/blood , Glucose/analysis , Kidney Failure, Chronic/bloodABSTRACT
La evaluación de las características de transporte de solutos y agua del peritoneo es esencial para adecuar la prescripción dialítica en pacientes portadores de enfermedad renal crónica. Existen una serie de modelos para realizar esta evaluación. El test de equilibrio peritoneal (PET) evalúa la capacidad de transporte del peritoneo clasificando a los pacientes en 4 categorías de transportador: alto, promedio alto, promedio bajo y bajo. El short PET realiza la misma evaluación en solo 2 h, y ha sido validado en pacientes pediátricos. Por otro lado, el MiniPET otorga información adicional al evaluar la capacidad de transporte de agua libre por los poros ultrapequeños, y el Accelerated Peritoneal Examination Time (APEX) evalúa el punto de intersección de las curvas de equilibrio de urea y glucosa, y ha sido propuesto como el tiempo de permanencia óptimo para lograr una UF adecuada. Se analiza la información actual sobre estos métodos diagnósticos, en particular los últimos aportes de la literatura respecto al transporte de agua libre vía aquaporinas, que podrían representar una herramienta importante para optimizar el transporte de agua y solutos en pacientes en diálisis peritoneal crónica, en particular respecto al pronóstico cardiovascular.
An evaluation of the characteristics of peritoneal solute and water transport is essential to assess the suitability of prescribing dialysis in patients suffering from chronic renal disease. There are currently a series of models to perform this evaluation. The peritoneal equilibration test (PET) evaluates the peritoneal transport capacity, classifying the patients into four transport categories: high, high-average, low-average, and low. The short PET enables the same evaluation to be made in only 2 hours, and has been validated in paediatric patients. On the other hand, the MiniPET provides additional information by evaluating the free water transport capacity by the ultra-small pores, and the Accelerated Peritoneal Examination Time (APEX) evaluates the time when the glucose and urea equilibration curves cross, and has been proposed as the optimum dwell time to achieve adequate ultrafiltration. An analysis is presented on the current information on these diagnostic methods as regards free water transport via aquaporins, which could be an important tool in optimising solute and water transport in patients on chronic peritoneal dialysis, particularly as regards the cardiovascular prognosis.
Subject(s)
Humans , Child , Peritoneal Dialysis/methods , Aquaporins/metabolism , Renal Insufficiency, Chronic/therapy , Models, Biological , Biological Transport , Water/metabolism , Dialysis SolutionsABSTRACT
An evaluation of the characteristics of peritoneal solute and water transport is essential to assess the suitability of prescribing dialysis in patients suffering from chronic renal disease. There are currently a series of models to perform this evaluation. The peritoneal equilibration test (PET) evaluates the peritoneal transport capacity, classifying the patients into four transport categories: high, high-average, low-average, and low. The short PET enables the same evaluation to be made in only 2hours, and has been validated in paediatric patients. On the other hand, the MiniPET provides additional information by evaluating the free water transport capacity by the ultra-small pores, and the Accelerated Peritoneal Examination Time (APEX) evaluates the time when the glucose and urea equilibration curves cross, and has been proposed as the optimum dwell time to achieve adequate ultrafiltration. An analysis is presented on the current information on these diagnostic methods as regards free water transport via aquaporins, which could be an important tool in optimising solute and water transport in patients on chronic peritoneal dialysis, particularly as regards the cardiovascular prognosis.