The characteristic presentation of patients with upper gastrointestinal bleeding is
Oct 13, 2022
Source: Cainiu Health
Dr. Zhao Haiming
Introduction
A common characteristic manifestation in patients with upper gastrointestinal bleeding is melena. This typically occurs when ferrous ions from blood combine with sulfides in the intestine to form iron sulfide. If the bleeding volume is large, and the blood has not been mixed with gastric acid, pepsin, or gastrointestinal contents, the patient may vomit bright red blood or dark red clots. If blood loss reaches approximately 15% of total blood volume, shock may occur.
The characteristic manifestations in patients with upper gastrointestinal bleeding typically include melena, hematemesis, and shock.
1. Melena
In patients with upper gastrointestinal bleeding, melena is a relatively common manifestation when the amount of bleeding is small. It usually occurs when ferric ions in the blood are reduced to ferrous ions by gastric acid or pepsin, then combine with sulfides in the intestine to form iron sulfide, resulting in black, tarry stools.
2. Hematemesis
If the bleeding volume is large and rapid, and the blood has not been mixed with gastric acid or pepsin or food in the gastrointestinal tract, or if the bleeding site is located above the pylorus, patients may vomit fresh red blood or dark red clots.
3. Shock
If the bleeding volume is substantial, patients may experience symptoms such as palpitations, fatigue, and dizziness. When blood loss reaches approximately 15% of total blood volume, orthostatic hypotension may occur, leading to visual obscurations or syncope. As the condition progresses, signs of shock such as pallor, tachycardia, and even mental apathy may develop.
