Sonographic Diaphragm Function in AECOPD

"Sonographic parameters of the diaphragm:~* Thickening Fraction (TF); (Diaphragm thickness end-inspiration- Diaphragm thickness end-expiration) / Diaphragm thickness end-expiration. (continuous variable).~* Diaphragm end-expiratory thickness: Diaphragm thickness at end-expiration (continuous variable)~* Diaphragm excursion (DE): diaphragm inspiratory amplitude during deep breathing (continuous variable)."