Fluid Overload in Pediatric Acute Respiratory Distress Syndrome after Allogeneic Hematopoietic Cell Transplantation

The aim of the study is to examine the relationship between fluid overload (FO) and severity of respiratory dysfunction in children post-hematopoietic cell transplantation (HCT) with pediatric acute respiratory distress syndrome (PARDS). This investigation was a secondary analysis of a multicenter retrospective cohort of children (1month to 21 years) post-allogeneic HCT with PARDS receiving invasive mechanical ventilation (IMV) from 2009 to 2014. Daily FO % (FO%) and daily oxygenation index (OI) were calculated for each patient up to the first week of IMV (day 0 = intubation). Linear mixed-effect regression was employed to examine whether FO% and OI were associated on any day during the study period. In total, 158 patients were included. Severe PARDS represented 63% of the cohort and had higher mortality (78 vs. 42%, p <0.001), fewer ventilator free days at 28 (0 [IQR 0–0] vs. 14 [IQR 0–23], p <0.001), and 60 days (0 [IQR 0–27] v. 45 [IQR 0–55], p <0.001) relative to non-severe PARDS. Increasing FO% was strongly associated with higher OI (p <0.001). For children with 10% FO, OI was higher by nearly 5 points (adjusted β 4.6, 95% CI [2.9, 6.3]). In subgroup analyses, the association between FO% and OI was strongest among severe PARDS (p <0.001) and during the first 3 days elapsed from intubation (p <0.001). FO% was associated with lower PaO2/FiO2 (adjusted β −1.92, 95% CI [−3.11, −0.73], p = 0.002), but not mean airway pressure (p = 0.746). In a multicenter cohort of children post-HCT with PARDS, FO was independently associated with oxygenation impairment. The associations were strongest among children with severe PARDS and early in the course of IMV.