Fluid overload before continuous hemofiltration and survival in critically ill children: a retrospective analysis

Abstract

Objective: Continuous venovenous hemofiltration (CVVH) is used for renal replacement and fluid management in critically ill children. A previous small study suggested that survival was associated with less percent fluid overload (%FO) in the intensive care unit (ICU) before hemofiltration. We reviewed our experience with a large series of pediatric CVVH patients to evaluate factors associated with outcome.

Design: Retrospective chart review.

Setting: Tertiary children's hospital.

Patients: CVVH pediatric ICU patients from November 1997 to January 2003.

Interventions: None.

Measurements and main results: %FO was defined as total fluid input minus output (up to 7 days before CVVH for both hospital stay and ICU stay) divided by body weight. One hundred thirteen patients received CVVH; 69 survived (61%). Multiple organ dysfunction syndrome (MODS) was present in 103 patients; 59 survived (57%). Median patient age was 9.6 yrs (25th, 75th percentile: 2.5, 14.3). Median %FO was significantly lower in survivors vs. nonsurvivors for all patients (7.8% [2.0, 16.7] vs. 15.1% [4.9, 25.9]; p =.02] and in patients with > or =3-organ MODS (9.2% [5.1,16.7] vs. 15.5% [8.3, 28.6]; p =.01). The Pediatric Risk of Mortality Score III at CVVH initiation also was associated with survival in these groups, but by multivariate analysis, %FO was independently associated with survival in patients with > or =3-organ MODS (p =.01).

Conclusions: Survival in critically ill children receiving CVVH in this large series was higher than in previous reports. CVVH survival may be associated with less %FO in patients with > or =3-organ MODS. Prospective studies are necessary to determine whether earlier use of CVVH to control fluid overload in critically ill children can improve survival.