Impulse oscillometry (IOM) is the latest modification of forced oscillation method, which does not require inforced exhalations. In the literature there is evidence of the possibility of using IOM in the diagnosis of obstructive disorders of central and peripheral respiratory tract. At the same time, the sensitivity and specificity of this method require further study.

AIM OF STUDY

Analysis of capabilities of IOM in the diagnosis of dysfunctions of bronchopulmonary system and the identification of most informative test indicators that correlate with spirometry, bodyplethysmography (BPG) parameters.

MATERIALS AND METHODS

78 patients with bronchial asthma (BA) of moderate severity allergic genesis were examined. In all patients, control over BA was not achieved. The comparison group consisted of 40 healthy patients, not suffering from respiratory diseases.

RESULTS

The IOM indices were in significant correlation with most spirometry and BPG parameters. In 55 (70%) patients, the parameters of absolute frequency dependence — Delta (Rrs5 — Rrs20) were increased. In 69% of cases in BA patients, an increase in the area under the Xrs curve was observed in the frequency range from 5 Hz to resonance frequency (AX), in 40% of patients, the values of respiratory impedance component Rrs5 and reactance deltaXrs5 did not differ from the values in comparison group.

CONCLUSIONS

During spirometry, airway obstruction was detected in 22 (28%) patients, according to BPG — in 46 (59%), when using IOM method — in 58 (74%). The most informative for detecting violations of the ventilation function of lungs are the IOM parameters Delta (Rrs5 — Rrs20), Delta (Rrs% Rrs20) and RF. The IOM method may be more informative in the diagnosis of early obstructive disorders.