The clinical manifestations of upper gastrointestinal bleeding mainly depend on the amount and speed of the patient's bleeding. Clinically, vomiting blood and black stool are characteristic manifestations of upper gastrointestinal bleeding. Secondly, if the patient has a large amount of bleeding, it can lead to a rapid decrease in circulating blood volume and subsequent peripheral circulatory failure. Patients may experience dizziness, palpitations, fatigue, and even fainting. At this point, it is crucial to actively replenish blood volume and stop the bleeding, and provide symptomatic treatment. Thirdly, blood tests can reveal signs of hemorrhagic anemia in patients. Fourthly, after gastrointestinal bleeding, patients generally develop a low fever within 24 hours, which must be actively managed.