DLCO

The carbon monoxide transfer factor (english transfer factor of the lung for carbon monoxide, DLCO ) is a medical measure of the diffusion capacity of the lungs, that is, for gas exchange between blood and air in the alveoli. It is part of the usual lung function measurements. For example requests the current S3 guideline for lung cancer that is determined prior to surgical removal of a lung of DLCO ( it should be at least 60% of the standard amount ).

To assess the lung function of both parameters of ventilation (spirometry ) and the diffusion must be determined in order to detect obstructive and restrictive disorders can. To put it simply remains DLCO with pure respiratory disorders such as bronchial asthma normal, but decreases with disorders of the pulmonary alveoli membrane such as sarcoidosis, alveolitis or emphysema.

Since the oxygen concentration in the blood can be determined only with difficulty, is used for the measurement of CO as well soluble in the blood test gas that does not exist. In common Einatemzugmethode the patient breathes, a test gas having 0.2% carbon monoxide as deeply as possible, and then stops for 10 seconds, the air to. The during this time dissolved in the blood CO concentration can be determined from the exhaled gas. The unit is mmol / min / kPa; practically, however, the percentage deviation from the norm of healthy subjects is given. In the used low concentration of CO acts to health.

The carbon monoxide transfer factor was first proposed in 1957 by the Cambridge physiologist Francis John Worsley Roughton ( 1899-1972 ) as a function parameter.

Swell

• R. Kramme: medical technology. Springer 2006, ISBN 3540341021, pp. 120-122.