carbon monoxide diffusing capacity


Also found in: Acronyms, Wikipedia.

carbon monoxide diffusing capacity

A clinical test which provides an objective measure of lung function. It reflects the lung's ability to take up an inhaled nonreactive test gas—e.g., carbon monoxide (CO)—which binds to haemoglobin with such a high affinity that virtually all of the CO reaches the alveolar space. The CO crosses the alveolar air-blood barrier, reaching the red cells, binds to haemoglobin and is removed with the exhaled gas.