The morbidity rate of Stanford A type Acute Aortic Dissection（AAD） has been increasing, about 5-10/100,000* per year. Emergency surgery has been the main treatment for Acute Aortic Dissection, however perioperative mortality rate can be as high as 15~30%. Acute lung injury (ALI) is one of the main complications that happen during the perioperative period, which by itself covers 30%-50% of the overall mortality rate. Both domestic and foreign countries lack researches on risk factors, pathogenesis, disease progression and outcome of ALI, which happen during the perioperative period of Acute Aortic Dissection patients.

This topic study follow projects in the preoperative of Acute Aortic Dissection'surgery

1. hemodynamic changes (aortic dissection resulting in acute aortic regurgitation, cardiac tamponade and proximal high blood pressure)
2. ischemia - reperfusion injury of aortic dissection distal organ
3. Aortic intima-media exposure cause coagulation / fibrinolytic system function disorder
4. systemic inflammatory response syndrome; use relevant clinical radiographic parameters, indicators of respiratory mechanics (oxygenation index and lung injury index) and biochemical indicators.

To discuss risk factors and possible mechanisms of ADD patients with pre-operative ALI and observe their influences on the progress and prognosis of AAD, to explore early intervention in the preoperative for possible risk factors and mechanisms and to evaluate their influences on the prognosis, to achieve the purpose of reducing AAD perioperative mortality of ALI and medical expenses.

Inclusion Criteria:

• AAD patients within 48 hrs of onset who are prepared for aortic surgery
• Age between 18 and 70
• Willing to sign the informed consent

Exclusion Criteria:

• A history of chronic respiratory disease before onset
• A history of chronic heart failure or coronary heart disease before onset
• A history of chronic liver or kidney dysfunction before onset
• Severe central nervous system syndrome after admission
• Refuse to sign the informed consent