Disposable vs. conventional NPPV in acute respiratory acidosis
Ertugrul Demir, Meltem Songur Kodik, Ozlem Inci, Ilhan Uz, Mehmet Birkan KorganAbstract
Objectives
Acute respiratory acidosis requires ventilatory support. Noninvasive positive pressure ventilation (NPPV) may be delayed in crowded emergency settings. Disposable systems may offer advantages, but evidence remains limited.
Methods
This prospective, single-center observational study included adults with acute respiratory acidosis requiring NPPV from September 2024 to April 2025. Patients received conventional ventilator-based NPPV or a disposable oxygen-driven bilevel CPAP/NPPV system according to clinician decision. The primary outcome was 60-min arterial pH; secondary outcomes included physiological responses, intubation, and 24-h mortality.
Results
Of 323 screened patients, 204 were analyzed: 100 conventional and 104 disposable-system patients. After adjustment for baseline imbalances, 60-min arterial pH did not differ significantly between groups; HC3 robust-standard-error and BCa-bootstrap sensitivity analyses gave the same inference. Intubation and 24-h mortality were similar. Exploratory longitudinal analyses suggested improvement in pH and PaCO 2 , but these findings were hypothesis-generating.
Conclusions
Because device allocation was not randomized and the groups differed at baseline in disease-severity variables, these data do not support a reliable efficacy comparison between the two systems and should not be interpreted as evidence of equivalence or superiority. Larger randomized or rigorously controlled studies are needed to clarify the role of disposable noninvasive ventilation in acute hypercapnic respiratory acidosis.