Forderungen für die Funktionsdiagnostik: Minimal-Maximalprogramm

Summary

Summarizing I have in Fig. 1 listed schematically the methods needed for lung function measurements. As minimum programme for ventilation investigations there is required a method to measure the mechanics of respiration and to determine the various phases of vital capacity. By means of these methods it is possible to judge adequately the clinically important and frequent obstructive ventilation disturbances and its functional importance. In case of “restrictive” lung disease it is necessary — when an obstructive ventilation disturbance can be excluded — to register additionally static and dynamic compliance.

For diagnosing respiratory failure in case of ventilation abnormalities, the investigation programme has to be enlarged by blood-gas analysis at rest and during effort. This request is especially urgent in case of uncomplicated restrictive ventilation troubles if no sufficiently accurate methods are available to quantitatively estimate the ventilation disturbance. Blood-gas analyses should be made at rest as well as during effort. For clinical questioning it will be possible in some cases to forget about the determination of the diffusing capacity. The latter enables only an insight in the alveolocapillary gas-exchange, when, before, ventilation abnormalities were excluded.

To judge the pulmonary situation, one is dependent on the clinical findings including electrocardiogram and X-ray picture. The exclusion of a ventilation disturbance or of a pathological alteration of the blood-gases permits, however, a certain conclusion a posteriori regarding the perfusion conditions within the lungs on account of the close relationships between alveolar ventilation and circulation.