Hypoxia and Medicine

What technologies allow the measurement of oxygen saturation and carbon dioxide concentrations in blood?

Describe and explain the conditions in which these technologies are used.

Public Comments

1. A pulse oximeter clips onto your finger - or other 'thin' areas where blood vessels run close to the surface of the skin (earlobe, toe) - and passes light through the finger to a receptor on the other end. Since haemoglobin, when attached to oxygen is bright red, it would absorb a certain differing amount of light to deoxygenated haemoglobin which is a darker red. The technology uses the variation in light reaching the receptor to measure oxygen saturation. As it uses light for measurement, it cannot be used in excessively bright areas. Arterial Blood Gas is a test using blood taken from an artery - i.e. blood moving away from the heart and usually oxygenated. It uses a machine to calculate the oxygen saturation and co2 concentration in the blood. It cannot be used to constantly monitor these measurements (eg. in surgery), and there are also criteria to meet in order to receive an accurate reading (cooler blood, no bubbles etc).