TaskList

To Do's (aka. things I could use help with):

• I had a long conversation with a pulmonologist to discuss the critical features of a proper ventilator and trade offs. Here are my notes. If you know someone with domain expertise, I would like confirmation that my take away notes are reasonable since this will drive priorities on engineering effort/conversations.
• Develop a simple low-cost sensor configuration for tidal volume measurement. Real ventilators have a "loop display" that is volume/pressure which provides an indicator of lung compliance
• Alarms for out of target (too low, too high) or out of target range flow/volume.
• Design modifications to recapture exhaust to minimze addition viral spread. This only works in already "dirty" environments, where there is likely already airborne droplets containing virus - such as quarnateened spaces or other negative air pressure environments.
• Develop Arduino compatible algorithms to align blower cycle to the breathing cycle by looking at backpressure load on the blower, or very simple air pressure sensor that can be inserted into the output of the pump. For ease of developing algorithms see Jupyter notebook with data visualization.
• Solutions to prevent the system from becoming unsafe if power is lost. It's not obvious to me on how to do this. Ideas are welcome.
• Develop a low-cost simple minute volume sensor/approximator. Here is some information about the downsides of being over/under on target volume. Critical care seems to want up to 10-12L/Min.

Completed To Do's

• Done - Most equipement has a 22mm I.D. and 24mm OD. Westmed and Qosina are distubutor options with online catalogs - Get access to of the appropriate measurements for ET, and dual circuit ventilator tubes. I don't yet understand the off the self options tube for managing inspirary/expiratory flow. In particular how expiratory flow is prevented from going down the inspiratory circuit, and how inspiratory IPEP/EPAP doesn't create flow out the expiratory circuit.
• Done - Functionality of low cost blower demonstrated in Tracked Issue by @adamcullen Thanks, Adam! - Test with a simple inflator pump and achieve the same pressure control.
• Done - wiki page for filter adapter - A 3D model for an inline air filter with link to common filter supply such as this.
• Done - AirBreak - Figure out how to reprogram an existing BiPAP. If this operating mode is helpful, there's a large number of these devices already in the field which could be enabled. I don't have good stats on the popularity of different makes/models. There could be on the order of a 1M devices worldwide?
• Done** - IMT Analytics has calibrated test lungs that are available in the low hundreds of dollars. - Test lung sourcing/research. Example high end one from Michigan Instruments.
• Paused - Have a contact, but don't want to compete with medial components right now. Alternative components need engineering verification - A supply chain person that can help us find good suppliers of parts, if there is desire to make these. I don't have a supply chain setup. The few parts I have on hand may not be easily sourcable in any volume quickly.