[Comparison of the effect of CPAP+PPS mode and CPAP+ASB mode in weaning on acute exacerbation of chronic obstructive pulmonary disease patients].

Objective: To investigate the effect of different appropriate modes of weaning from mechanical ventilation (MV) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD).

Methods: Patients with AECOPD and mechanically ventilated by orotracheal intubation, suitable for continuous positive airway pressure+proportional pressure support (CPAP+PPS) and CPAP+assisted spontaneous breath (ASB) ventilation mode for weaning from MV, admitted to intensive care unit (ICU) of Tianjin Third Central Hospital form January 1st, 2016 to December 31st, 2017 were enrolled. When the patients recovered to spontaneous respiration and down regulation of ventilator support frequency to 10 bpm, they were taken ventilator weaning in CPAP+PPS and CPAP+ASB mode according to the random number table method, respectively. Basic characteristics, ventilator parameters, the incidence of high man-machine confrontation (man-machine confrontation index > 10%) and clinical outcomes (ventilator weaning time, which was defined as the time from randomization to successful weaning from MV, ventilator weaning failure times, the duration of MV, the length of ICU stay and the length of hospital stay) were compared between the two groups.

Results: Eighty-seven AECOPD patients were selected, 44 in CPAP+ASB group and 43 in CPAP+PPS group. There was no significant difference in gender, age, acute physiology and chronic health evaluation II (APACHE II), sequential organ failure score (SOFA), Glasgow coma score (GCS), Charsen index and the highest arterial blood carbon dioxide partial pressure (PaCO), the lowest arterial oxygen partial pressure (PaO) and tidal volume (VT) at the time of onset between the two groups. Compared with CPAP+ASB group, incidence of high man-machine confrontation was significantly decreased in CPAP+PPS group [9.30% (4/43) vs. 27.27% (12/44), P = 0.027], and the airway occlusion pressure (P0.1) was significantly decreased [cmHO (1 cmHO = 0.098 kPa): 2.21±0.83 vs. 2.63±0.94, P = 0.032], and the failure rate of the first spontaneous breathing trial (SBT) was significantly decreased [6.98% (3/43) vs. 22.73% (10/44), P = 0.039], ventilator weaning time, the length of ICU stay and the length of hospital stay were significantly shortened [ventilator weaning time (hours): 12.73±14.23 vs. 50.64±38.11, the length of ICU stay (hours): 254.53±108.06 vs. 344.93±124.95, the length of hospital stay (days): 18.53±7.59 vs. 26.64±11.22, all P < 0.05]. However, there was no significant difference in PaCO, duration of MV, ICU mortality and hospital mortality between the two groups.

Conclusions: Compared with CPAP+ASB ventilation mode, CPAP+PPS ventilation mode can reduce respiratory muscle load, promote respiratory function recovery, and reduce the occurrence of man-machine confrontation, which is beneficial to AECOPD patients taking ventilator weaning, and can significantly shorten the ventilator weaning time of patients and further shorten the hospitalization time.