Perform US of diphragm during all spontaneous breathing trials and afer extubation every 72 hours until ICU discharge.
Patient supine with 30 degrees HOB elevation.
Use 4-2 probe on area between rib 8 and rib 9, midaxillary line, directed cranially (oblique transverse section)
Identify diaphragm in 2D mode based on phrenicopleural fascia (a bright curved line).
Visualize right hemidiaphragm on transhepatic section trough kidney and L hemidiaphragm on transsplenic section.
Measure diaphragmatic movement directly in 2D mode.
Measure diaphragmatic excusrsion in M-mode using beam directed perpendicular to diaphragmatic line during inspiration. (Excursion is measured as distance in mm between point A at beginning of inspiration and point B at end of inspiration.
Obtain 3-4 measurements each evaluation and record best value.
performed into a coronal plan. The ultrasound scan used in the present study was Philips Envisor Series.
Definition of DD
Diaphragmatic dysfunction was defined, during quiet breathing, as a diaphragmatic excursion of 11 mm or less in 2D mode17 and of 10 mm or less on the right and 11 mm or less on the left in M-mode.15 Ultrasound results from the most trained examiner (LFM) were considered as the reference for DD diagnosis.