[Oscillo-resistometry in bicycle ergometry stress]

With the aid of a Siregnost FD 5, modified with a reference resistance of 2 kPa/l/s, measurements of the oscillatory airway resistance were carried out in 16 healthy subjects and 22 patients with asthma aged between 7 and 22 years, during and after physical exercise. As a consequence of increasing turbulent flow, in the case of the patients with healthy airways, a significant increase in the airway resistance (RmOS) occurred under conditions of physical exercise, which was due to the most part to an increase in the phase angle. Initial measurements with the custo vit suggest that the used reference resistance in the FD 5 is responsible for this. In the case of asthmatic patients, the average increase in RmOS was more marked. However, two groups of patients were differentiable: in the first group, under conditions of exercise, a decrease in the initially slightly elevated airway resistance occurred, while in the other patient group the airway resistance remained unchanged at a high level, even after exercise. In two patients, marked obstruction occurred on conclusion of the exercise examination. In one of the subjects with supposedly healthy airways, a bronchospasm developed during physical exercise and made it necessary to abandon the examination. Thus, there can be no doubt as to the clinical relevance of such measurements during and after physical exercise.