3.6.7 Devices and techniques that limit iatrogenic blood loss

Read through these techniques. Then have a look at the map at the foot of the page and see how they fit into the context of blood conservation.

It has been estimated that patients can lose up to 1.3 litres of blood during a hospital stay because of extensive taking of samples.  These techniques can significantly reduce the quantity of blood taken for testing.  Iatrogenic means "adverse effects caused by the treatment by the physician". The term implies that the effects could be avoided by proper and judicious care.

        Transcutaneous oximeter

Transcutaneous monitoring offers an effective, non-invasive, and continuous monitoring of pO₂ (partial pressure of oxygen) and pCO₂ (partial pressure of C0₂.)

        Pulse oximeter

A device that monitors the amount of oxygen carried by the haemoglobin in red blood cells. In bloodless medicine, any blood a patient loses is not replaced by transfusion, so it is extremely important to monitor how much oxygen the patient's body is receiving from the remaining blood.

The principle of pulse oximetry is based on the red and infrared light absorption characteristics of oxygenated and deoxygenated haemoglobin. Oxygenated haemoglobin absorbs more infrared light and allows more red light to pass through. Deoxygenated (or reduced) haemoglobin absorbs more red light and allows more infrared light to pass through. Red light is in the 600-750 nm wavelength light band. Infrared light is in the 850-1000 nm wavelength light band.

        Microsampling equipment

Using electrochemistry, analyzers can perform a complete range of common blood tests from only 3-5 drops of blood.

        Essential tests only

Reducing the number of tests to only the immediate, essential tests reduces the volume of blood needed for samples.

        Multiple tests per sample

        Smaller samples (paediatric-sized tubes)