Extracorporeal membrane oxygenation in patients with hematologic malignancies: a systematic review and meta-analysis

Hematological malignancies (HM) have been, until recently, viewed as contraindications to extracorporeal membrane oxygenation (ECMO) due to bleeding and infectious complications. However, conflicting literature regarding whether ECMO should be used for patients with HM still exists. We conducted a random effects meta-analysis to investigate the outcomes of patients with HM on ECMO. We searched Medline, Embase, Scopus, and Cochrane through 10 October 2021. Risk of bias and certainty of evidence were assessed using the JBI checklists and GRADE approach respectively. Thirteen observational studies (422 patients with HM, 9778 controls without HM) were included. The pooled in-hospital mortality for patients with HM and those with hematopoietic stem cell transplants for HM indications needing ECMO were 79.1% (95%CI: 70.2-86.9%) and 87.7% (95%CI: 80.4-93.8%), respectively. Subgroup analyses found that mortality was higher in adults than children (85.1% vs 67.9%, p_interaction = 0.003), and in Asia compared to North America and Europe (93.8% vs 69.6%, p_interaction < 0.001). Pooled ECMO duration was 10.0 days (95%CI: 7.5-12.5); pooled ICU and hospital lengths of stay were 19.8 days (95%CI: 12.4-27.3) and 43.9 days (95%CI: 29.4-58.4) respectively. Age (regression coefficient [B]: 0.008, 95%CI: 0.003-0.014), proportion of males (B: 1.799, 95%CI: 0.079-3.519), and ECMO duration (B: - 0.022, 95%CI: - 0.043 to - 0.001) were significantly associated with higher mortality. In-hospital mortality of patients with HM who needed ECMO was 79.1%, with better outcomes in children, and in North America and Europe. ECMO should not be regarded as routine support therapy in these patients but can be carefully considered on a case-by-case basis.