Asynchronies in NIV With External Gas

The procedure was performed in the patient's room during his or her hospital stay to avoid additional visits for study participation. The patient was placed in the supine position, and the usual ventilator interface was placed in a single-limb system, along with the commercial ventilator to be studied. The ventilator model were evaluated at bedside in random order. The parameters of the ventilator were the same as those that the patients used at home (that is, unlike the bench study, the sensitivity of the trigger was not modified). A external polygraph was used to moritor the study, with the incorporation of thoracic and abdominal bands and parasternal electromyography, to better evaluate asynchronies, in addition to pulse oximetry control. The ventilation periods were 1 minute (without gas, gas, without gas). This sequence was performed twice in each group of established conditions.