The in-vitro performance of invasive mechanical ventilators in lung model

Objective To evaluate the technical performance and patient-ventilator synchronization of different invasive mechanical ventilators. Methods Six ventilators were tested using the ASL5000 active lung simulator. Ventilators were categorized by air supply type: central (Dräger V600, Maquet Servo-u, Mindray SV800) and turbine-based (Savina 300, SV300, Resvent RS300). The measured parameters included tidal volume (VT), plateau pressure (Pplat), positive end-expiratory pressure (PEEP), peak pressure (Ppeak), time to reach 90% of inspiratory pressure (T (90%)), triggering delay (DT), and leak compensation. Ventilators were evaluated in volume assist-control (V-A/C), pressure assist-control (P-A/C), and pressure support ventilation (PSV) modes under acute respiratory distress syndrome (ARDS) and chronic obstructive pulmonary disease (COPD) conditions using ASL5000™ lung simulator, with or without intentional leak (4.4 L/min). For each ventilator under these different conditions, we analyzed pressurization accuracy, VT accuracy, inspiratory muscle effort, and response efficiency. Results The pressurization accuracy of ventilators with central air supply did not differ significantly from that of turbine-driven ventilators during V-A/C and P-A/C ventilation, irrespective of spontaneous breathing or air leakage. The mean absolute errors of target VT were 8.9% (V600), 10.3% (Servo-U), 14.4% (SV800), 4.6% (Savina300), 18.8% (SV300), and 19.9% (RS300), and ventilators with central air supply generally have better VT accuracy, except for Savina300 ( P <0.05). In V-A/C with different triggers and leaks, Savina 300 showed comparable stability and accuracy to central air supply ventilators in the ARDS lung model. Significant differences in VT accuracy and PEEP were observed among ventilators (P<0.05). During PSV, V600 and Servo-u exhibited shorter response efficiency than SV800 under identical simulated patient effort (P<0.05), suggesting faster and easier patient support. Conclusions The Savina 300 alone matched or exceeded central air supply models in pressurization and VT accuracy. In terms of inspiratory trigger performance, the V600 and Servo-u demonstrated better patient-ventilator synchrony than the SV800 under PSV mode.