Machine determining oxygenation factor in living tissue - measures extraction ratio between oxygen in blood and oxygen use

摘要

The system determines the level of tissue oxygenation by calculating the balance, or 'extraction ratio' - ER- between available oxygen or 'oxygen flux' and the oxygen use by the tissues - VO2. The techniques involves the measurement of the strong binding between haemoglobin and oxygen. The oxygen flux is calculated by multiplying the heart output rate, or 'heart minute volume' by the proportion - CACO2- of oxygen in arterial blood. The extraction ratio, ER is then calculated by dividing the oxygen use figure - VO2 by the oxygen flux. The application contains no technical details of the construction or operation of the machine.