Long-term lung function recovery after ECMO versus non-ECMO management in acute respiratory failure: a systematic review and meta-analysis.

Background: Extracorporeal membrane oxygenation (ECMO) is increasingly employed to support lung function in patients with acute respiratory failure (ARF). However, the long-term outcomes of the approach have not been encouraging when compared to those of conventional mechanical ventilation. Further, the long-term effects of ECMO on lung function and recovery are unclear. For this review, we examined the long-term lung function outcomes of patients with ARF treated with and without ECMO.

Methods: We searched the Embase, CENTRAL, Web of Science, and PubMed sites for studies comparing long-term (≥ 6 months) pulmonary function test results in patients with ARF treated with and without ECMO published until January 2024. We conducted a meta-analysis for percentage predicted values.

Results: We included five studies. Our meta-analysis showed similar values of forced vital capacity (FVC%) (MD, 0.47; 95% CI, -3.56-4.50) and forced expiratory flow in the first second % (MD, 1.79; 95% CI, -2.17-5.75) in patients with ARF treated with or without ECMO. The FEV1/FVC % values were slightly higher in patients treated with ECMO than in those without ECMO (MD, 2.03; 95% CI, 0.01-4.04; p-value = 0.05). According to the meta-analysis, the values for total lung capacity % (MD, -3.20; 95% CI, -8.83-2.44) and carbon monoxide diffusion capacity % (MD, -0.72; 95% CI, -3.83-2.39) were also similar between patients undergoing ECMO and those without it.

Conclusion: The meta-analysis of a small number of studies with significant selection bias indicates that patients with ARF treated with ECMO may have comparable long-term pulmonary function recovery to those treated with conventional strategies. Further investigations including a larger number of patients and focusing on the long-term impact of ECMO are needed to supplement the current evidence.