Clinical Research Directory

Inclusion Criteria: 1. Age ≥ 18 years old 2. Accept VA-ECMO or VV-ECMO 3. the ECMO team believes that systemic anticoagulation is necessary and that APTT should be maintained at 40-60s. 4. sign the informed consent form Exclusion Criteria: 1. previous history of allergy to heparin or bivalirudin 2. previous diagnosis of heparin-induced thrombocytopenia. 3. the pre-random ECMO assistance time is more than 48 hours. 4. pregnant female 5. have participated in this study before. 6. the researchers believe that there are other factors that are not suitable to participate in this study.