Primary aim
diaphragmatic dysfunction
DYSFUNCTION
Every morning, between 10 and 11 a.m., we used the Philips CX 50 ultrasound machine with a linear probe (5–12 MHz) to measure diaphragm thickness. The probe was placed perpendicular to the skin in the zone of apposition between the mid-axillary or antero-axillary line, in the 8th to 11th intercostal spaces. We measured diaphragm thickness perpendicular to the direction of the fibres between the pleural and peritoneal membranes, but not including the membranes. As previously described [If the SBT failed, and the decision to extubate was delayed, the value used for the analysis was that measured on the day of the extubation. Based on the results of our meta-analysis on the predictive values of the DTF on weaning failure, we defined diaphragmatic dysfunction as a DTF < 30% and considered a DTF of 20% to indicate severe dysfunction [