Extracorporeal Membrane Oxygenation Cannulation Timing in the Pediatric Myocarditis Population: An Exploratory Analysis From the Extracorporeal Life Support Organization Registry

OBJECTIVES:. Children presenting with acute myocarditis may experience rapid clinical deterioration requiring extracorporeal membrane oxygenation (ECMO); however, our understanding of best practices and timing of ECMO initiation are lacking. We explored the relationships between pre-cannulation factors and survival in this high-acuity patient population. DESIGN:. Retrospective review of a large international registry. Primary outcome was survival to hospital discharge, stratified by incident cardiac arrest (CA) prior to ECMO and time to cannulation after intubation. SETTING AND SUBJECTS:. The Extracorporeal Life Support Organization registry was queried for patients less than or equal to 18 years old receiving ECMO support for myocarditis between 2007 and 2018. Exclusion criteria included being nonindex runs, non-venoarterial ECMO or missing data points for main variables studied. INTERVENTIONS:. None. MEASUREMENTS AND MAIN RESULTS:. Population characteristics and survival were compared using t test, Wilcoxon rank-sum test, or Fisher exact test. Multivariable logistic regression was used for significant factors in the unadjusted logistic regression. Among 506 index ECMO runs in pediatric patients with myocarditis, survival for the cohort was 72%, with no difference between early and late eras (2007–2012 vs 2013–2018; p = 0.69). Survivors demonstrated higher pre-ECMO pH levels as well as shorter intubation-to-cannulation (ITC) times (3 hr [interquartile range (IQR)], 1–14 hr vs 6 hr [IQR, 2–20 hr]; p = 0.021). CA occurred within 24 hours prior to ECMO cannulation, including extracorporeal cardiopulmonary resuscitation, in 54% of ECMO runs (n = 273). Accounting for the interaction between pre-ECMO CA occurrence and ITC time, longer ITC time remained associated with lower survival for patients who did not experience a CA prior to ECMO, with adjusted odds ratio of 0.09 (IQR, 0.02–0.40; p = 0.002) for ITC time greater than or equal to 18 hours. CONCLUSIONS:. The results of this multicenter analysis of ECMO utilization and outcomes for pediatric myocarditis suggest that patients approaching ECMO cannulation who have not experienced CA may have better survival outcomes if cannulated onto ECMO early after intubation

RBC Transfusion Induced ST Segment Variability Following the Norwood Procedure

Objectives:. The transfusion of stored RBCs decreases nitric oxide bioavailability, which may have an adverse effect on vascular function. We assessed the effects of RBC transfusion on coronary vascular function by evaluating the relationship between myocardial oxygen delivery and demand as evidenced by ST segment variability. Design:. Retrospective case-control study. Setting:. Nine-hundred seventy-three–bed pediatric hospital with a 54-bed cardiovascular ICU. Patients:. Seventy-three neonates with hypoplastic left heart syndrome following the Norwood procedure, 38 with a Blalock-Taussig shunt and 35 with a right ventricle to pulmonary artery shunt. Interventions:. RBC transfusion. Materials and Main Results:. High-frequency physiologic data were captured 30 minutes prior to the initiation of (baseline) and during the 120 minutes of the transfusion. A rate pressure product was calculated for each subject and used as an indicator of myocardial oxygen demand. Electrocardiogram leads (aVL, V1, II) were used to construct a 3D ST segment vector to assess ST segment variability and functioned as a surrogate indicator of myocardial ischemia. One-hundred thirty-eight transfusions occurred in the Blalock-Taussig shunt group and 139 in the right ventricle to pulmonary artery shunt group. There was no significant change in the rate pressure product for either group; however, ST segment variability progressively increased for the entire cohort during the transfusion, becoming statistically significant by the end of the transfusion. Upon subgroup analysis, this finding was noted with statistical significance in the Blalock-Taussig shunt group and trending toward significance in the right ventricle to pulmonary artery shunt group. Conclusions:. We found a significant increase in the ST segment variability and evidence of myocardial ischemia temporally associated with RBC transfusions in neonates following the Norwood procedure, specifically among those in the Blalock-Taussig shunt group, which may impact immediate and long-term outcomes