[Adaptation parameters in non-invasive mechanical ventilation. Experimental comparative study]

Area of Science:

• Biomedical Engineering
• Respiratory Physiology
• Medical Device Technology

Background:

• Non-invasive mechanical ventilation (NIV) units are critical for respiratory support.
• Effective triggering mechanisms are essential for patient-ventilator synchrony and comfort.
• Evaluating the performance of different NIV units is vital for clinical selection.

Purpose of the Study:

• To compare the pressure and flow triggering response of six non-invasive mechanical ventilation units.
• To assess ventilator performance across simulated normal, obstructive, and restrictive lung models.
• To identify ventilators with optimal triggering characteristics for patient adaptation.

Main Methods:

• Utilized a lung simulator to model different respiratory conditions.
• Recorded analog signals for volume, pressure, and flow using a Mingograph 34 polygraph.
• Calculated key parameters including negative trigger pressure, trigger time, and peak inspiratory flow cycling.

Main Results:

• Respironics STD20 (RR) and Puritan Bennet 335 (PB) exhibited the best trigger response (pressure < -1 cmH2O, trigger time < 100 ms).
• Vintil+ (VP) showed the poorest response.
• RR cycling closely matched standard parameters (5-25% peak inspiratory flow), while other units showed deviations.

Conclusions:

• The Respironics STD20 (RR) unit demonstrated the most consistent and homogeneous behavior across all studied parameters.
• Optimal trigger response is a key factor influencing patient adaptation to mechanical ventilation.
• Findings provide valuable data for selecting NIV units that enhance patient-ventilator synchrony.