Design and Implementation of a Computer-Controlled Hybrid Oscillatory Ventilator

Area of Science:

• Biomedical Engineering
• Respiratory Physiology
• Mechanical Ventilation

Background:

• Lung function and gas exchange can be improved in heterogeneous lungs using multifrequency oscillatory ventilation (MFOV).
• Conventional high-frequency oscillatory ventilation (HFOV) uses a single frequency, limiting potential benefits.
• A need exists for advanced ventilators capable of MFOV and other ventilation modes.

Purpose of the Study:

• To design and test a computer-controlled hybrid oscillatory ventilator.
• To enable multifrequency oscillatory ventilation (MFOV), high-frequency oscillatory ventilation (HFOV), conventional mechanical ventilation (CMV), and oscillometry.
• To evaluate the device's performance and efficacy in maintaining gas exchange.

Main Methods:

• Developed a computer-controlled hybrid oscillatory ventilator with an iterative spectral feedback controller.
• Tested the device's performance against commercial ventilators in volume-controlled mode.
• Validated oscillatory modes in a mechanical test lung (4–20 Hz, 5–30 cmH2O mean airway pressure).
• Conducted proof-of-concept experiments in a porcine model of acute lung injury.

Main Results:

• The device met performance standards of commercial ventilators in volume-controlled mode.
• Oscillatory ventilation modes met design specifications in a mechanical test lung.
• The ventilator successfully maintained adequate gas exchange in a porcine model of acute lung injury.
• The device demonstrated capability in generating diverse ventilation waveforms.

Conclusions:

• A novel hybrid oscillatory ventilator was successfully designed and tested.
• The device can generate various conventional and oscillatory ventilation waveforms.
• This technology holds potential for enhancing gas exchange and providing less injurious ventilation.