Acute Aortic Syndrome (AAS) is a common feature of acute aortic wall events, including aortic dissection, intramural hematoma, aortic ulceration and aortic trauma, and occurs in up to 35 cases per 100,000 cases per year between the ages of 65 and 75 years. Ulinastatin has antiinflammatory activity and suppresses the infiltration of neutrophils and the release of elastase and chemical mediators from neutrophils. Recent studies have shown that ulinastatin may be cytoprotective against ischemia-reperfusion injury in the liver, kidney, heart, and lung. The authors aim to examine the association between decreased release of inflammatory response to urinary trypsin inhibitor treatment and decreased myocardial and lung injury after acute aortic syndrome surgery.

Inclusion Criteria:

• The patients are conformed to 2010 ACC/AHA guidelines for the diagnosis and treatment of thoracic aortic disease (TAD) within two weeks of onset;
• Patients with type a acute aortic syndrome confirmed clinically and radiologically and planning to undergo aortic surgery were enrolled.
• The patients' age of 18 years or older.
• Agree to participate in the study and sign the informed consent.

Exclusion Criteria:

• Patients allergic to Ulinastatin;
• Lactating women and pregnant women;
• Patients with mental diseases;
• Refuse to participate in this study and refuse to sign the informed consent.