الفهرس 
Mechanical VentilationOnly 14 pages are availabe for public view
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Abstract
Weaning is the process of decreasing the amount of support that the patient receives from the mechanical ventilator, so the patient assumes a greater proportion of the ventilatory effort. Traditional methods of weaning include spontaneous breathing trials (SBTs), progressive decreases in the level of pressure support during pressure support ventilation (PSV), and progressive decreases in the number of ventilator-assisted breaths during intermittent mandatory ventilation (IMV) Cardiogenic pulmonary edema has been recognized as a frequent cause of weaning failure. A spontaneous breathing trial (SBT) induced an elevation in the left ventricular filling pressure (LVFP), which plays a key role in weaning failure. Tissue Doppler is a technique that directly measures myocardial velocities. The early diastolic mitral annulus velocity (Ea) has been shown to be a relatively load independent measure of myocardial relaxation. When Ea is combined with pulsed Doppler mitral flow in early diastole E, the resulting E/Ea ratio closely correlated with the measured invasive LVFP.