Internal bleeding detection technique

2002/06/07 Carton Virto, Eider - Elhuyar Zientzia

• Medikuntza

Internal bleeding is very difficult to detect and, in most cases, is only detected when it is too late to do anything. When internal bleeding occurs, the body contracts the veins to ensure that the blood reaches the vital organs with enough pressure. Therefore, at first a decrease in blood pressure is not appreciated. The sudden drop occurs when 25% to 30% of blood has been lost, and in many cases it is too late.

Chris Gregory, head of Sarnoff, believes the new device can quickly and easily detect bleeding. He says the amount of oxygen the eye takes from the blood reflects
the amount of blood in the circulatory system. The blood that is pumped through the artery of the eye is a blood rich in oxygen, with an oxygenation level always close to 95%, regardless of whether there is bleeding or not. And the tissues of the eye always
consume the same amount of oxygen. But when there is less blood available, that is, when it is bleeding, the tissues will take more oxygen from the blood and therefore the blood less oxygen from the vein of the eye will return to the circulatory system. Remember that the arteries carry clean blood (full of oxygen and nutrients) and the veins dirty blood (less oxygen and full of waste).

The device designed by the company Sarnoff is able to detect the oxygen level of the actual blood mentioned. For Chris Gregory, lowering oxygen would indicate bleeding.

The device uses laser and four-color light to measure. Blue and green light emitting lasers are used to detect eye veins and differentiate arteries and veins. Two other lasers emit red and infrared light and are used to measure oxygen levels. Oxygen-rich blood is redder than minimal, so they absorb light emitted by lasers differently. A microcomputer processes the data and provides a real artery and oxygen levels.

Knowing that there is bleeding, it is only necessary to detect its location by X-rays and put the appropriate treatment. These treatments are often successful if they are known to be given. The company Sarnoff is now manufacturing a portable device, since the first ones are too large.