Dark tarry stools containing decomposing blood are known as:

Dark tarry stools containing decomposing blood are referred to as melena. This term specifically describes the appearance of the stools which is a result of bleeding that has occurred in the upper gastrointestinal tract. When blood moves through the digestive system, it undergoes a process of digestion and enzymatic breakdown, leading to the characteristic dark color and tarry consistency.

This condition often suggests that the bleeding source is relatively proximal to where the blood is exited as stool, which can include conditions such as gastric ulcers or varices. Understanding terms like melena is crucial for EMTs, as it helps in assessing the patient's condition and the potential risks associated with gastrointestinal bleeding. Recognizing symptoms accurately can be critical in prioritizing care and informing subsequent medical treatment.