Revista chilena de pediatría
versión impresa ISSN 0370-4106
AZOCAR P., Marta et al. Estimation of total body water using deuterium in children undergoing peritoneal dialysis. Rev. chil. pediatr. [online]. 2003, vol.74, n.5, pp. 504-510. ISSN 0370-4106. http://dx.doi.org/10.4067/S0370-41062003000500007.
Paedriatric peritoneal dialysis (PD) is the most frequent form of treatment for end stage chronic renal failure. The dialysis dose (Kt/V) needs to be adjusted periodically, which requires the estimation of total body water (TBW) using different methods or formulas. The ideal method is the use of isotopes oxygen -18 or D20 (deuterium), which are difficult to apply in the routine clinical situation. Objective: To estimate the TBW in children using deuterium and compare the results with those obtained using formulas commonly used in clinical practice. To calculate the dosis of dialysis according the TBW obtained using the formulas or with deuterium. Patients and methods: 8 children, 6 boys with a mean age of 6.6 years (range 4-14) undergoing CAPD. TBW was measured using a dilution method with deuterium according to the protocol of Plateau. A dose of 1-2 gms of 99.8% deuterium was used, and saliva samples collected at 0, 2, 3 and 4 hours post administration. The results were compared with the formulas of Mellits and Cheek and TBW= kg* 0.6. Statistical analysis was carried out using the Stata 7.0 program with a p value of 0.05 being significant. Results: TBW using deuterium was 2.9% lower than the value obtained using the formula of Mellits and Cheek, and 1.6% higher than the value obtained using the weight. The average value of Kt/V using a TBW based on the different methods was 2.08, 2.08 and 1.90 respectively (p = ns). Conclusions: The estimation of the TBW using different formulas is not significantly different to that using deuterium, permiting their routine use in clinical practice with an adequate level of confidence
Palabras clave : Total body water; perotoneal dialysis; deuterium.