Sonography indicators of diaphragm and their correlation with spirometry data in healthy individuals: a prospective study

Abstract

OBJECTIVE: Revealing the correlation between sonography indicators of diaphragm performance and spirometry data of healthy persons. MATERIALS AND METHODS: The study was conducted at the Almazov National Medical Research Centre. The structural (thickness) and functional (thickening fraction and excursion of diaphragm) state of diaphragm of 50 healthy individuals (female — 30) was assessed with an ultrasound machine, and the spirometry characteristics of the external breathing apparatus were assessed with a ventilator. Afterwards the statistical and correlation analysis was conducted. RESULTS: It was possible to assess the thickness of diaphragm on both sides and the diaphragm excursion on the right in all subjects, the diaphragm excursion on the left — only in 20 % of subjects. Spirometry has been performed in all subjects. The obtained data are consistent with the literature. In particular, sonography and spirometry indicators of the healthy individuals are within reference values. Inspiratory muscles strength has also proved to be consistent with the literature data. Correlation analysis has revealed no statistically significant relationship between the examined sonography and spirometry parameters. In addition, no relation between age and sonography indicators of diaphragm has been found. There are weak statistically significant relations revealed between the structural and functional state of diaphragm and such anthropometric characteristics of the subjects as body mass and body mass index. CONCLUSIONS: Sonography indicators of diaphragm performance do not correlate or correlate poorly with spirometry data. There is no reason to use sonography of diaphragm in healthy individuals since it does not practically provide any additional information about the state of external respiratory apparatus.