To determine the association of venovenous extracorporeal membrane oxygenation (VV-ECMO) initiation with changes in vasoactive-inotropic scores (VISs) in children with pediatric acute respiratory distress syndrome (PARDS) and cardiovascular instability.
Retrospective cohort study.
Single academic pediatric ECMO center.
Children (1 mo to 18 yr) treated with VV-ECMO (2009–2019) for PARDS with need for vasopressor or inotropic support at ECMO initiation.
Measurements and Main Results:
Arterial blood gas values, VIS, mean airway pressure (mPaw), and oxygen saturation (Spo2) values were recorded hourly relative to the start of ECMO flow for 24 hours pre-VV-ECMO and post-VV-ECMO cannulation. A sharp kink discontinuity regression analysis clustered by patient tested the difference in VISs and regression line slopes immediately surrounding cannulation. Thirty-two patients met inclusion criteria: median age 6.6 years (interquartile range [IQR] 1.5–11.7), 22% immunocompromised, and 75% had pneumonia or sepsis as the cause of PARDS. Pre-ECMO characteristics included: median oxygenation index 45 (IQR 35–58), mPaw 32 cm H2o (IQR 30–34), 97% on inhaled nitric oxide, and 81% on an advanced mode of ventilation. Median VIS immediately before VV-ECMO cannulation was 13 (IQR 8–25) with an overall increasing VIS trajectory over the hours before cannulation. VISs decreased and the slope of the regression line reversed immediately surrounding the time of cannulation (robust p < 0.0001). There were pre-ECMO to post-ECMO cannulation decreases in mPaw (32 vs 20 cm H2o, p < 0.001) and arterial Pco2 (64.1 vs 50.1 mm Hg, p = 0.007) and increases in arterial pH (7.26 vs 7.38, p = 0.001), arterial base excess (2.5 vs 5.2, p = 0.013), and SpO2 (91% vs 95%, p = 0.013).
Initiation of VV-ECMO was associated with an immediate and sustained reduction in VIS in PARDS patients with cardiovascular instability. This VIS reduction was associated with decreased mPaw and reduced respiratory and/or metabolic acidosis as well as improved oxygenation.