Autopsy Histopathologic Lung Findings in Patients Treated With Extracorporeal Membrane Oxygenation

Extracorporeal membrane oxygenation (ECMO) is increasingly used in the treatment of respiratory and cardiac failure, but data describing lung histopathology in ECMO recipients are limited.

To examine pulmonary histopathologic findings in patients who underwent venovenous (VV) ECMO for pulmonary reasons or venoarterial (VA) ECMO for cardiac indications shortly before death, and to determine if the pulmonary changes provided insights into therapy that may prevent complications and improve outcome.

We conducted a retrospective study of lung autopsies, from VV and VA ECMO recipients and patients with acute respiratory distress syndrome (ARDS) and non-ECMO treatment, between 2008 and 2020 in Silesia Center for Heart Diseases in Zabrze, Poland.

Among 83 ECMO patients (42-64 years; men, 57 [68.7%]), the most common histopathologic findings were bronchopneumonia (44 [53.0%]), interstitial edema (40 [48.2%]), diffuse alveolar damage (DAD; 32 [38.6%]), hemorrhagic infarct (28 [33.7%]), and pulmonary hemorrhage (25 [30.1%]). DAD was associated with longer ECMO treatment and longer hospital stay. The use of VV ECMO was a predictor of DAD in patients with ARDS and undergoing ECMO, but it also occurred in 21 of 65 patients (32.3%) in the VA ECMO group, even though VA ECMO was used for heart failure.

Although DAD was significantly more common in lung autopsies of VV ECMO patients, one-third of VA ECMO patients had histopathologic changes characteristic of ARDS. The presence of DAD in lung autopsies of patients treated with VA ECMO indicates that in these patients, protective lung ventilation should be considered.