LAUSR

BACKGROUND Retroperitoneal hemorrhage (RPH) is a rare and severe complication in patients undergoing extracorporeal membrane oxygenation (ECMO). Clinical diagnosis is difficult. CASE SUMMARY Three cases of RPH patients with corona virus disease-19 (COVID-19) were included in this study. All three suffered from respiratory failure, were treated with veno-venous or veno-arterial-venous ECMO, and experienced RPH during ECMO treatment. Two of the COVID-19 cases were diagnosed after the patients experienced abdominal pain. The other patient exhibited decreases in the ECMO circuit flow rate and hemoglobin level. Two cases were treated by transcatheter arterial embolization, and one was treated conservatively. The hemorrhage in each of the three cases did not deteriorate. Satisfactory treatment results were achieved for the three patients because of prompt diagnosis and treatment. CONCLUSION Although the incidence of RPH during ECMO treatment is low, the risk is increased by anticoagulant use and local mechanical injury. If declines in blood flow velocity and hemoglobin are detected, RPH should be considered, and prompt aggressive therapy should be started.