The upper gastrointestinal system primarily refers to bleeding from the digestive system above the Treitz ligament. Therefore, if there is acute massive bleeding in the digestive tract, patients may present with symptoms such as vomiting blood and black stools. If the bleeding is significant and blood volume rapidly decreases, it can cause acute peripheral circulatory disorders, and may even be life-threatening. The causes of upper gastrointestinal bleeding include long-standing conditions like peptic ulcers, rupture of esophagogastric varices, acute erosive hemorrhagic gastritis, and stomach cancer, among others. If upper gastrointestinal bleeding occurs, patients should actively seek medical attention at major hospitals' gastroenterology departments, undergo relevant examinations, and receive prompt treatment.