Clinical outcomes in critically ill children on extracorporeal membrane oxygenation with severe thrombocytopenia

Introduction As international guidelines suggest keeping the platelet count between 50 and 100 × 10 9 cells/L in children on extracorporeal membrane oxygenation (ECMO), platelet transfusions are administered to two-thirds of ECMO days, and up to 70% of these patients still bleed. We aim to describe outcomes in critically ill children who develop severe thrombocytopenia on ECMO. Methods Single-center retrospective study, enrolling critically ill children on ECMO admitted at Children’s Memorial Hermann, TX, between 1/2018 and 12/2022, with at least one platelet count below 50 × 10 9 cells/L (severe thrombocytopenia). Platelet counts were measured four times a day. We report platelet transfusion, bleeding, hemolysis, and clotting events within 6 h after transfusion, as well as ECMO duration and mortality. Results We enrolled 54 patients representing 337 ECMO days and 1190 platelet counts. Median weight was 3.7 kg and 54% were male. Severe thrombocytopenia was observed in 56% of platelet counts. Severe thrombocytopenia was not associated with bleeding in the subsequent 6 h (18% vs 20%, p = .95), but was associated with more frequent platelet transfusions (18% vs 11%, p = .001). There was no correlation between time spent with severe thrombocytopenia and the duration of ECMO (R 2 = 0.03). While the time spent with severe thrombocytopenia was not associated with on-ECMO mortality rate ( p = .36), there was an association with in-hospital mortality rate ( p = .003). Conclusions Our results indicate a restrictive platelet transfusion strategy is not associated with higher proportions of subsequent bleeding, duration of ECMO, or on-ECMO mortality rate. Multicenter studies are needed to evaluate further the appropriateness of this strategy.