Abstract
Introduction: Pneumonia often leads to impaired airway clearance and reduced oxygenation. Conventional physiotherapy has limited benefits, whereas newer approaches such as cough assist devices may play a more effective role in secretion clearance and improvement of oxygenation status.
Objectives: This study aimed to comparatively evaluate the effect of a cough assist device versus physiotherapy on hemodynamic status and oxygen saturation (O2 Sat) in patients with pneumonia.
Materials and Methods: This double-blind clinical trial study was conducted on patients with pneumonia undergoing mechanical ventilation (MV) at Firouzgar hospital in Tehran from July 2025 to February 2026. A total of 92 eligible patients were enrolled and randomly assigned to two groups: an intervention group (cough assist device, 45 patients) and a control group (chest physiotherapy, 47 patients). Hemodynamic indices (heart rate and respiratory rate) were monitored using cardio–pulmonary monitoring, and arterial blood gas (ABG) parameters (PCO2 , pH, O2 Sat, and HCO₃⁻) were measured to assess gas exchange and acid–base balance. Outcomes were evaluated at three time points; before the intervention, one day after the intervention, and two days after the intervention, and the results were compared between the two groups using statistical tests.
Results: The findings indicated that, compared with physiotherapy, the cough assist device improved arterial O2 Sat status, leading to increased O2 Sat, improved pH, and reduced PCO2 (P<0.05), whereas no significant differences were observed between the two groups in HCO3 levels or hemodynamic indices such as heart rate and respiratory rate (P>0.05).
Conclusion: The results indicate that, compared with chest physiotherapy, cough assist devices can significantly improve arterial O2 Sat status and pH balance in mechanically ventilated patients with pneumonia, without adverse effects on hemodynamic stability. These findings support the integration of cough assist devices as a safe and effective adjunct in respiratory care in the intensive care unit (ICU).
Trial Registration: The trial protocol was approved by the Iranian Registry of Clinical Trials with code (IRCT20251111067960N1), and ethical code from Iran University of Medical Sciences (IR.IUMS.FMD. REC.1404.198).