Study On The Use Of Noninvasive Ventilation Immediately Following Early Extubation In Patients With Severe Acute Respiratory Distress Syndrome

Objective:To investigate the timing and value of noninvasive ventilation (NIV) as a weaning tool immediately after early extubation in patients with acute respiratory distress syndrome (ARDS). Methods:A randomized, prospective, controlled clinical study in a single center of a25-bed adult respiratory ICU in a university hospital was carried out in a23-month period. All consecutive adult patients with severe ARDS secondary to surgically managed diseases were recruited in our respiratory intensive care unit (ICU) according to strict inclusion and exclusion criteria. All patients underwent endotracheal intubation and were mechanically ventilated. Every12h during the first3days, the lung recruitment maneuver was performed during pressure control ventilation (PCV) with high pressure of20cmH2O and positive end-expiratory pressures (PEEP) of25or20cmH2O for2min. After lung recruitment, all patients were ventilated with synchronized intermittent mandatory ventilation (SIMV) or assistant/control ventilation (A/C), with tidal volumes (VT) of6-8ml/kg (ideal body weight) and PEEP15-25cmH20. When most acute infiltrating lesions had resolved on chest imaging, the oxygen index (PaO2/FiO2)≥200mmHg and <250mmHg under PEEP of8cmH2O and pressure support of12cmH2O, and on premature extubation, all patients were randomised into two groups:i) patients received noninvasive ventilation (NIV) immediately after extubation (sequential group); and ii) patients continued to undergo invasive mechanical ventilation via intubation or tracheostomy with an endotracheal tube (control group). The baseline data (gender, age, acute physiology and chronic health evaluation Ⅱ score, etc.) and the number of reintubations in the sequential group were recorded. The duration of invasive mechanical ventilation and total mechanical ventilation, ICU length of stay, the incidence of ventilator-associated pneumonia (VAP), and other indexes were analyzed between the two groups. Results:Fifty-three consecutive adult patients were enrolled (sequential group,26patients; control group,27). The period of endotracheal intubation was7.00(6.75,9.50)d and two patients (7.7%) experienced reintubation in sequential group. The baseline parameters did not significantly differ between the two groups (P>0.05). The duration of invasive mechanical ventilation [7.0(6.8,9.5) d vs.21(17,25) d], duration of total mechanical ventilation (18±4.1d vs.22±7.3d) and length of ICU stay (21±4.1d vs.28±8.1d) were significantly different between groups (all P<0.05). Conclusion:NIV immediately following early extubation facilitates the discontinuation of mechanical ventilation in selected patients with ARDS, in addition to reducing duration of total mechanical ventilation and the length of ICU stay.