Accurate dry weight assessment is difficult in pediatric hemodialysis patients but is essential to prevent chronic fluid overload, hypertension, and cardiovascular morbidity. A noninvasive monitoring (NIVM) of hematocrit-guided ultrafiltration algorithm was studied prospectively in 20 pediatric hemodialysis patients. The algorithm targeted the first 50% of total goal ultrafiltration to be removed during the first hour of dialysis with a maximum blood volume change of 8 to 12% per hour. The second 50% was removed during the remaining treatment time with a maximum blood volume change of 5% per hour. Data that were collected at baseline and 6 mo included weight, BP, number of antihypertensive medications, 24-h ambulatory BP monitoring (ABPM), echocardiogram, and ultrafiltration-associated symptoms. Sixteen of 20 enrolled patients completed the study. No difference was seen between baseline and 6-mo weight, predialysis casual BP, nighttime ABPM, or left ventricular mass index. There was a decrease in postdialysis casual systolic BP, daytime ABPM, number of antihypertensive medications prescribed, and rate of intradialytic events related to ultrafiltration (all P < or = 0.05). Adoption of a standardized NIVM-guided algorithm led to (1) improved ABPM profiles, (2) decreased antihypertensive medication burden, and (3) decreased ultrafiltration-associated symptoms. Wider use of NIVM-guided ultrafiltration may decrease cardiovascular morbidity in pediatric hemodialysis patients.