LAUSR

Learning Objectives: The time course and trajectory of right ventricular (RV) systolic function in pediatric ARDS (PARDS) are unknown. We assessed RV systolic function and evidence of pulmonary hypertension (PH) in serial transthoracic echocardiograms (echos) in PARDS patients. We hypothesized that new or persistent RV systolic dysfunction would be associated with worse patient outcomes. Methods: Single center, retrospective cohort study of patients with PARDS admitted between July 2012 and June 2016. Two clinically obtained and serial echos within the first 7 days of PARDS were analyzed for RV systolic function [tricuspid annular peak systolic excursion (TAPSE), RV global longitudinal strain (GLS), RV free wall strain (FWS), RV fractional area change (FAC)] and evidence of pulmonary hypertension (PH) by two investigators blinded to clinical information. Abnormal RV GLS and FWS were defined as ≤ -2 standard deviations below institutional controls. Nonparametric statistical analyses were performed. Covariates are presented as median (IQR). Results: Sixty-one PARDS patients had technically adequate serial echos during the study period [age 4.6 years (1.6–10.5); oxygenation index at 24 hours 8.0 (4.8–12.9); mortality 23%]. Time from PARDS diagnosis to first echo was 0.5 days (0.4–0.8) while the time from first to second echo was 2.1 days (1.3–3.2). When compared to patients with improved or normal RV function on second echo, patients with new or persistent RV dysfunction as measured by RV GLS had longer duration of mechanical ventilation in survivors (31.0 vs 10.5 days, p=0.01) and less ventilator free days at 28 days (0.0 vs. 17.0 days, P<0.01) but there was no difference in mortality (31% vs 18%, p=0.30). Neither new or persistent PH nor low TAPSE were associated with worse outcomes in this cohort. Conclusions: Within the first 7 days of PARDS, new or persistent RV systolic dysfunction as measured by RV GLS is associated with worse patient outcomes. Longitudinal echocardiographic assessment of RV systolic function may be important for risk stratification and identification of therapeutic targets in PARDS patients.