The accuracy of a continuous volumetric balancing system in pediatric continuous renal replacement therapy

In pediatric continuous renal replacement therapy (CRRT) patients, accurate ultrafiltration (UF) measurement is essential, as both over- and under-UF may result in suboptimal outcomes. Traditionally, CRRT has relied on scale-based UF measurements; however, the recent development of a continuous volumetric balancing system has allowed for the advent of scale-less CRRT.

To assess the accuracy of the volumetric balancing system, we designed a continuously measuring digital scale, which accounted for dialysate use and collected effluent, allowing us to independently measure UF volume and compare it with the machine reported UF volume.

In four low weight (6.9-16.7 kg) pediatric CRRT patients, we measured the UF volume over 20 separate runs, comprising a total of 318 hours. Over this time, the total measured UF volume was 50,550 mL ± 296 mL, whereas the total reported UF volume was 50,733 mL, a difference of 183 mL ± 296 mL (0.6 ± 0.9 ml/h), or 0.4 ± 0.6%. For each patient, over 48-112 hours per patient, the differences between the total measured and total reported UF volumes ranged from -7.8 ± 1.7 ml/h to +9.7 ± 1.8 ml/h, or -6.0 ± 1.3% to +5.4 ± 1.0%.

In low-weight, pediatric CRRT patients, the scale-less continuous volumetric balancing system delivers accurate ultrafiltration.