Maximum Expiratory Pressure in Induced Cough as a Predictor of Extubation Failure in Intensive Care Unit Patients on Mechanical Ventilation Ready to Extubate. A Single-arm Open Clinical Trial.

After completing the spontaneous breathing trial (SBT), with the extubation decision defined by the physician in charge of the patient and maximal expiratory pressure (MEP) as usually measured greater than 30 centimeters of water (cmH2O). Following this, the patient was allowed to rest for 5 minutes in the same condition. With the patient in the supine position sitting 45 ° to 60 °, the closed suction catheter was removed, an elbow was placed at 90 ° and a bacterial filter in series with the endotracheal tube (ET), an adapter was also coupled with a outlet port to the aneroid pressure gauge. In series an inspiratory unidirectional valve was placed that did not allow expiration. Immediately 2 ml of physiological solution was slowly instilled through the port in the 90º elbow to trigger the cough reflex. The presence or absence of reflex cough and the MEP during induced cough (MEPic) value were verified.

As a safety method, the procedures were stopped if the patient presented signs of intolerance such as respiratory rate (RF)> 35 breaths per minute, saturation <90%, heart rate (HR)> 140 beats per minute or increase of 20 % of resting levels.