Non-invasive ventilation for acute respiratory failure: Pressure support ventilation vs. pressure-controlled ventilation

Background: The best ventilator mode for patients receiving non-invasive ventilation (NIV) has not been clarified. This study compared the effectiveness of two pressure-targeted modes, i.e., pressure support ventilation (PSV) and pressure-controlled ventilation (PCV), in patients receiving NIV. Methods: This was a prospective multicentre observational study of NIV use for acute respiratory failure (ARF) in adult patients. We compared the two pressure-targeted modes in terms of NIV success and complication rates. Results: Among 176 patients receiving NIV, 88 patients were included in the study (PCV mode, n=29; PSV mode, n=59). The study population had a median age of 73.0 years and median body mass index of 20.8 kg/m2. The applied inspiratory positive airway pressure (IPAP) was higher in patients with PCV than in those with PSV [18.0 cmH2O (15.0-20.5 cmH2O) vs. 15.0 cmH2O (12.0-17.0 cmH2O), respectively, P=0.001]. More patients with PCV received sedatives and experienced dry mouth than those with PSV; however, the incidences of large leaks were low in both groups (n=5 vs. n=2, respectively). With regard to NIV outcomes, 24 (27.2%) patients experienced NIV failure and 13 (14.8%) died in hospital. PSV mode was a significant factor for NIV success [odds ratio (OR), 2.303; 95% confidence interval (CI), 1.216 to 4.360] in multivariate analyses and this association remained significant in a 1:1 matched cohort (n=29 per group). Conclusions: In contrast to PCV mode, PSV mode was significantly associated with NIV success in the intensive care unit setting, particularly when large leaks were not a major concern. Nevertheless, further well-designed multicenter, protocol-driven randomized controlled trials are warranted.