Analysis the Vocs in Upper GI Bleeding Patients

This project aims to collect the exhaled breath of patients with acute upper gastrointestinal bleeding clinically, divide them into large, small and no bleeding groups according to the results of gastroscopy, analyze the characteristics of volatile organic compound components in exhaled breath, construct a discriminant model, and then analyze the sensitivity and specificity, and the target sensitivity and specificity reach more than 0.7, and formulate diagnostic criteria.