Inclusion Criteria:  Patients who received cardiovascular surgery fulfilled three or more of the following criteria:  Pao2/Fio2 ratio less than or equal to 250mm Hg, Respiratory rate greater than or equal to 30 breaths/min, Blood urea nitrogen greater than 20mg/dL, WBC count < 4,000 cells/mm3 or >15 000 cells/mm3 not due to other causes, Core temperature < 36°C or >38.5°C, Receiving treatment with vasopressors at therapeutic doses after adequate fluid resuscitation, radiographic findings of new pulmonary infiltrate(s). Agree to participate in the study and sign the informed consent.  Exclusion Criteria:  Pregnant and lactating women. Allergic to Xuebijing and its ingredients, or have severe allergies. Mental illness with poor compliance. Severe primary disease (active pulmonary tuberculosis, asthma, cystic pulmonary fibrosis, pulmonary sarcoidosis, pulmonary interstitial fibrosis, unresectable tumors, blood diseases, Alzheimer s disease, or HIV). Participation in other clinical trials in the previous 30 days. Patients who are unsuitable for participation or unable to participate in this trial according to the judgment of the investigators (existing risk of potential medical disputes, and severe heart failure limiting the amount of liquid intake).