Intrapulmonary Percussive Ventilation

1. Intrapulmonary Percussive Ventilation Carl W. Israel*, Tim Weaver*, James Grotting*, Joshua Gess^, Ryan Winter^, Dr. Paul King* *Department of Biomedical Engineering, Vanderbilt University ^Department of Mechanical Engineering, Vanderbilt University INTRODUCTION CIRCUIT DESIGN PROTOTYPE DESIGN Bulk Flow Respiration Percussive Ventilation • Pressure Regulators Specified to withstand maximum pressure of wall inlet (50 psi) Optimize cost and precision • MicroKing Air Control Valve Operating schematics 0-100 Hz 0-125 psi Provides oscillating characteristic • SureVent Emergency Transport Ventilator Supplies bulk flow ventilation characteristic Portable, Inexpensive, Hands-free • Outgoing Air Fed to endotracheal tube • Power Supply 12 V, 500 mA Power Supply • Lung Volume During Emergency Respiration • The average human has a total lung capacity of 4-6 liters • Even at vital capacity, about 25% of the lung volume remains (residual volume) • Residual volume can allow chemicals or other foreign substances to remain in the lung • CMOS 4047 Astable/Monostable Multivibrator • CMOS 4040 Ripple-carry Binary Counter/divider • 2N2222 Transistor • C1, R1 can be adjusted to obtain different frequencies • Percussive Ventilation Promotes Fluidic Mixing • Shorter bursts of air create a turbulent atmosphere • Fresh air mixes with residual volume • Clean air reaches alveoli more quickly • Allows for oxygen to be more efficiently absorbed • Waste gases are removed more efficiently CONCLUSIONS • Intrapulmonary percussive ventilation has many benefits over traditional ventilation. Currently the devices that provide percussive ventilation are extremely effective, but also extremely expensive. After constructing and testing our prototype, we determined that percussive ventilation can be provided at a much cheaper cost than is currently available. Even after adding costs incurred during a potential FDA approval process, the cost of our device would be much less than that of the incumbent design. Although frequency adjustability is compromised with our device, we have found that a frequency at or around 8 Hz is most effective, and is the most common setting for percussive ventilators. As mentioned in our future work and recommendations section, there are many improvements that can be made to our device that would increase its portability, ruggedness, and overall operational quality. A device which could provide percussive ventilation at a relatively low price could prove to be a great asset in the medical field. Overall, we have achieved our goal of constructing a inexpensive, functional ventilation system. PROJECT OBJECTIVES PROTOTYPE PERFORMANCE • Incumbent Design: Percussionaire VDR4 • High-frequency percussive ventilator • Incorporates air busts with bulk flow ventilation • Very expensive (~$10,000) • Project Goals: • Design and prototype an emergency ventilation system • Test performance of prototype • Mimic current intrapulmonary percussive ventilators • Bulk Flow Characteristic Bulk flow ventilation not typical, but these aspects are easily adjusted with Surevent • Percussive Flow Characteristic Obtained best result when device was oscillating at 8 Hz • Circuit Performance Poor quality components caused inconsistent operation • Other Observations Some air leakage at tubing joints caused pressure inconsistencies Tubing sizes could be varied to improve performance • Design Parameters: • Inexpensive • Durable • Independent of User • Portable FUTURE WORK & RECOMMENDATIONS • Apply for and obtain FDA approval • Continue safety testing • Machine custom parts to decrease size and increase portability and performance • Incorporate specialized, smaller, more precise regulators • Incorporate battery power source for increased portability • Remodel circuit to allow for adjustability of frequency • Replace circuit casing with a more durable, rugged box • Market device MARKET AND COST OVERVIEW Estimated Project Deployment Costs • Surevent Mechanical Ventilator ($60.00) • Tubing and Fittings ($15.00) • Solenoid Valve ($30) • Circuitry ($5.00) • Power Supply ($20.00) • Pressure Regulators ($40.00) TOTAL COST: $170.00 Who benefits from IPV? • Neonates with retained endobronchial secretions and/or with diffuse atelectasis • Children with mechanical breathing limitations • Patients with: cystic fibrosis, fibrocystic lung disease, cor pulmonale, chronic bronchitis, acute and chronic obstructive pulmonary diseases • Burn patients with pulmonary involvement • Post surgical patients with retained endobronchial secretions • Patients with chemical pneumonias secondary to aspiration or ineffective process SAFETY CONSIDERATIONS • Future work to improve safety Ensure the regulator valves are functional and properly set Addition of real-time pressure gauge, O2, and CO2 detector Water proof to prevent short circuit • Replace/sanitize components after each use Entire device is easily replaced. However, individual components can be sanitized if an efficient sanitizing method is developed. • Designsafe Analysis After Designsafe analysis, the highest risk for the patient is improper use of the device. • Power Failure In the case of power failure, the Surevent system would continue to work, allowing the patient to receive bulk flow ventilation ACKNOWLEDGEMENTS • Dr. Paul King • Associate Professor of Biomedical Engineering • Dr. Bob Galloway • Professor of Biomedical Engineering • Dr. Michael Goldfarb • Associate Professor of Mechanical Engineering • Dr. Franz Baudenbacher • Assistant Professor of Biomedical Engineering • Dr. Mark A. Stremler • Assistant Professor of Mechanical Engineering • Kevin Fite • Research Associate of Mechanical Engineering