Inclusion Criteria:  ECMO time ≥1 day Aged older than16 years old and less than 70 years old  Exclusion Criteria:  coma deep sedation muscle relaxation (RAAS-3-5) Active bleeding deep vein thrombosis High dose of vasoactive drugs unstable vital signs Acute stage of myocardial infarction (within 2d) Malignant arrhythmia pregnancy