Introduction: Pulmonary embolism (PE) is rare in the pediatric population. While outcomes for pediatric PE have been described, minimal data exists defining risk factors for extracorporeal life support (ECLS). Methods: Retrospective review of patients massive/submassive PE presenting to a quaternary children’s hospital from 2016-2022. Clinical variables were collected to assess risk stratification, process timelines, and overall outcomes. Results: Twenty-five patients presented with critical PE (64% females, median age 17 years (14.9, 17.7), median BMI 27) PE risk factors included: a family history of thrombosis (33%), personal history of DVT (50%), and a history of oral contraceptive use (44%). Median pulmonary embolism severity index (PESI) score was 57. All 25 patients underwent catheter-directed thrombolysis (CDT). ECLS was required in 9/25 (36%) for refractory cardiogenic shock and were distributed between three PE risk categories (high=2, intermediate=3, low=4). Pre-CDT variables did not differ between the ECLS and nonECLS groups, including PESI score, right ventricular dilation/strain, or serologic markers of cardiac output. Compared to the non-ECLS group, ECLS patients were more likely to require vasoactives pre-CDT (44% vs 6%, p=0.04) and have higher mean pulmonary artery pressures (52mmHg vs 36mmHg, p=0.004). The ECLS group required more ICU days (15 vs 2.5 days, p=0.004) and longer hospital length of stay (17 vs 5 days, p=0.018). Two deaths occurred in the cohort, both due to neurologic injury. Conclusions: One third of pediatric patients who presented with massive/sub-massive PE required ECLS support due to right ventricular failure. These patients were more likely to require vasoactives pre-CDT and demonstrate higher mean PA pressures. However, standard methods of risk stratification used in adults were unable to predict the degree of critical illness in pediatric patients. Further evaluation of pre-CDT variables is needed to hone risk stratification in this rare yet life threatening event.
VanCleve et al. (Sun,) studied this question.