On the flip side, blood that remains dark red even when it should be oxygen-rich might indicate problems with your hemoglobin. Conditions like carbon monoxide poisoning can change the way ...

Darker red blood may be a sign of bleeding in the small bowel or upper colon. Very dark or black-red blood often means there is bleeding in the stomach or other organs of the digestive system.

Although blood is a vital therapy for many patients, recent lessons from the bedside suggest that red blood cell transfusions may harbor a dark side. Red blood cell transfusion is associated with ...

Again, during your period, dark red period blood is totally normal – it’s blood that’s been in your vagina for longer and has oxidized as a result. But you should pay attention if you start ...

Dark red blood is drained from a patient’s body via a large tube inserted into their femoral vein in one leg. It is then passed through an artificial membrane in where it is oxygenated and ...