[The potentialities of capnography in the early diagnosis of obstructive ventilatory disorders]

A total of 52 subjects (27 normal persons not abusing tobacco-smoking and 25 tobacco-smokers without respiratory disorders) were examined for external respiration function. A study was also made of the capnography data. It has been demonstrated that the classical criteria of the functional disorders of ventilation (FVC, RFV1, RFV1/FVC, MPV) do not enable one to make an early diagnosis of the ventilatory alterations in subjects with a risk of the development of CNPD (in tobacco-smokers). Analysis of the last third of the forced expiration curve flow-volume appeared to be of great informative value. There was a marked correlation between the capnogram characteristics and external respiration function characterizing patency of the small bronchi. It is concluded that capnography can be used as a method for assessing bronchial patency. The most informative criteria of the capnogram are provided.