Design assessment and preliminary performance evaluation of a novel device for non-invasive emergency treatment of acute respiratory failure

Acute respiratory failure (ARF) requires rapid intervention to prevent patient deterioration and life-threatening complications. Early respiratory support through prehospital Continuous Positive Airway Pressure (CPAP) has been shown to improve ARF outcomes. However, existing CPAP devices present technical barriers for use in out-of-hospital emergency scenarios. This study presents the design and preliminary performance evaluation of a novel portable, ready-to-use CPAP device for out-of-hospital respiratory support. The device includes a blower providing steady air insufflation through a face mask, with Positive End-Expiratory Pressure (PEEP) regulated by two fixed-point PEEP valves. To identify optimized operational conditions ensuring target respiratory support, a lumped-parameter model (LPM) was developed to simulate device–patient interaction. Input data for the LPM included experimental characteristics of the device components. Simulations were conducted using breathing profiles representing varying ARF-like conditions and severity. Additionally, computational fluid dynamics (CFD) analysis was performed to assess the risk of CO 2 rebreathing through the mask. LPM simulations described the dynamic interaction between the breathing profile and device performances, and the consequent pressure and flow patterns during the respiratory cycle. Across all simulated conditions and device settings, PEEP remained close to the predefined target of 5 cm H 2 O without reaching critical thresholds, confirming design choices efficacy. CFD analysis indicated an end-expiratory residual CO 2 concentration of ~2%, suggesting a low risk of rebreathing between cycles. Our results confirmed the validity of our design solutions and suggest a potentially safe and efficient profile as a promising solution for early CPAP use in emergency settings.