Luo L, et al. - This study was designed to evaluate the different impacts of ultrasound-assessed cardiac and diaphragm function on extubation outcomes in difficult-to-wean patients. Researchers found that respiratory failure within 48 h could be predicted with the help of the ratio (E/Ea) of mitral Doppler inflow velocity (E) to annular tissue Doppler wave velocity (Ea) (average) after spontaneous breathing trial (SBT). However, for predicting re-intubation within 1 week in the respiratory failure subgroup, diaphragmatic excursion (DE) (average) after SBT could be helpful.