Decreasing intra-dialytic morbid events and assessment of dry weight in children on chronic hemodialysis using non-invasive changes in hematocrit.

Abstract

Achieving dry weight after hemodialysis (HD) is critical as chronic fluid over-load can result in left ventricular hypertrophy, while small fluid shifts may result in intra-dialytic morbid events (IME). In the pediatric population, estimating dry weight can be difficult due to growth while on dialysis. Continuous non-invasive monitoring of the hematocrit (NIVM) has been proposed as a more accurate method of estimating dry weight. Fifteen pediatric patients on chronic HD (6 males and 9 females; mean age 11.4 ± 2.28 years) were included in an uncontrolled prospective study involving three phases. In phase 1, patients were observed for one month for their dry weight and frequency of IME. Phase 2 consisted of using NIVM-guided ultrafiltration algorithm for rate of blood volume (BV) reduction and post-dialysis refill, recommending an intra-dialytic reduction in BV of 8% in the first hour and <4% per hour thereafter and without significant post-dialytic vascular refill. Phase 3 comprised a one month period for comparing the results. IME decreased from 33 episodes per 180 sessions in phase 1 to 4 per 180 sessions during phase 3 (P = 0.04), without a significant difference in pre-systolic or post-systolic or mean BP before and after the intervention (all P >0.1). In phase 1, 40% of patients experienced no IME, 33% experienced one or two IME while 27% experienced more than two IME; during phase 3, 80% experienced no IME, 20% experienced one or two IME while no one experienced more than two IME. NIVM can serve as an objective method for determining dry weight as well as predicting and preventing IME in the pediatric population on maintenance HD.