Impact of major bleeding and thrombosis on 180-day survival in patients with severe COVID-19 supported with veno-venous extracorporeal membrane oxygenation in the United Kingdom: a multicentre observational study

Bleeding and thrombosis are major complications in patients supported with extracorporeal membrane oxygenation (ECMO). In this multicentre observational study of 152 consecutive patients (>= 18 years) with severe COVID-19 supported by veno-venous (VV) ECMO in four UK commissioned centres during the first wave of the COVID-19 pandemic (1 March to 31 May 2020), we assessed the incidence of major bleeding and thrombosis and their association with 180-day mortality. Median age (range) was 47 years (23-65) and 75% were male. Overall, the 180-day survival was 70 center dot 4% (107/152). The rate of major bleeding was 30 center dot 9% (47/152), of which intracranial bleeding (ICH) was 34% (16/47). There were 96 thrombotic events (63 center dot 1%) consisting of venous 44 center dot 7% [68/152 of which 66 center dot 2% were pulmonary embolism (PE)], arterial 18 center dot 6% (13/152) and ECMO circuit thrombosis 9 center dot 9% (15/152). In multivariate analysis, only raised lactate dehydrogenase (LDH) at the initiation of VV ECMO was associated with an increased risk of thrombosis [hazard ratio (HR) 1 center dot 92, 95% CI 1 center dot 21-3 center dot 03]. Major bleeding and ICH were associated with 3 center dot 87-fold (95% CI 2 center dot 10-7 center dot 23) and 5 center dot 97-fold [95% confidence interval (CI) 2 center dot 36-15 center dot 04] increased risk of mortality and PE with a 2 center dot 00-fold (95% CI1 center dot 09-3 center dot 56) risk of mortality. This highlights the difficult balancing act often encountered when managing coagulopathy in COVID-19 patients supported with ECMO.