Analysis of the correlations between ultrasound-assessed diaphragm function and pulmonary function

This study aimed to explore diaphragm parameters measurable using ultrasound and analyse their correlations with pulmonary function to comprehensively assess their clinical value.

Patients diagnosed with pulmonary nodules or tumours at the thoracic surgery department of Gaozhou People's Hospital between August 2023 and June 2024 were included. Ultrasound assessments of diaphragm function were performed, measuring parameters such as diaphragm excursion, maximum excursion, thickness, thickening fraction, contraction velocity, excursion-time index, rapid shallow breathing index, thickening rapid shallow breathing index, and shear modulus. Pulmonary function tests, including forced expiratory volume (FEV₁), forced vital capacity (FVC) and FEV₁/FVC, were conducted. Bilateral hemidiaphragm parameters were compared, and their correlations with pulmonary function parameters were analysed.

A total of 79 patients (43 men and 36 women), with a mean age of 63.08 ± 11.76 years were included. Pulmonary function parameters were as follows: FEV₁: 2.01 ± 0.73 L, FVC: 2.58 ± 0.78 L, and FEV₁/FVC: 0.77 ± 0.11. Statistically significant differences were observed in bilateral hemidiaphragm parameters: diaphragm thickness at end-inspiration (DTei), diaphragm thickness at end-expiration (DTee), and the average and minimum diaphragm shear moduli at end-expiration (DSMe-avg and DSMe-min), while other diaphragm parameters showed no significant differences. Diaphragm excursion, diaphragm excursion-time index, and diaphragm rapid shallow breathing index were correlated with FEV₁ and FVC. During expiration, diaphragm shear modulus showed no significant correlation with pulmonary function parameters, whereas certain diaphragm shear modulus values exhibited weak correlations during inspiration.

Ultrasound technology offers a multifaceted approach to assess diaphragm function, encompassing parameters such as excursion amplitude, morphological changes, change velocity, stiffness, and elasticity, thereby demonstrating promising potential in diaphragm evaluation. Additionally, in studies correlating ultrasound-evaluated diaphragm function with pulmonary function, diaphragm excursion-time index and diaphragm rapid shallow breathing index have been found significant and worthy of further research.

Not applicable.