Faced with an extreme ventilator shortage, engineering students and tinkerers around the world are trying to come up with low-cost, DIY breathing machines. While clever and well-meant, most of these devices would be of little help to COVID-19 patients.
Demand for ventilators is just too high
Many COVID-19 patients need ventilators to help with breathing. Unfortunately, in places that the virus hit really hard, there just weren’t enough ventilators for the patients that needed them. The tragic scenes from countries like Italy may have been a major driving force behind the hunt for easy-to-build ventilators.
The art of the bodge
A quick search on the Internet reveals dozens of open-source ventilator designs that McGyver would be proud of. Most (if not all) are based around the bag valve mask (BVM):
Connecting this plastic bag with a tube that is inserted in patients’ trachea and pumping it delivers much needed air to patients’ lungs. Most designs come up with a clever way of automatically pressing and depressing the bag. Using everyday household items, these devices are usually very cheap and easy to produce, without the need of complex machining tools.
Homemade ventilators can only get you so far
Modern ventilators have many advanced features that help experts support patients’ breathing. These are just too advanced to be included in homemade ventilators:
| Feature | Medical Ventilator | McGyver Ventilators | Benefits |
| Pressure Control | ✔️ | ❌ | PC prevents the air being pushed too hard in patients’ lungs – causing severe lung damage. |
| Volume Control | ✔️ | ❌ / ✔️ | VC prevents too much air going into patients’ lungs – causing severe damage. |
| Patient-triggered breathing | ✔️ | ❌ | Supporting patient breathing instead of replacing it means that patients don’t have to be fully paralyzed. |
| Air heating and humidification | ✔️ | ❌ | Lungs are used to receiving warm and humid air thanks to our nostrils and trachea – this features mimics their function. |
| Positive End Expiration Pressure (PEEP) | ✔️ | ❌ | PEEP means that even at the end of expiration some pressure is still applied to patients’ lungs, keeping parts of the lung from collapsing. This is especially important in COVID-19. |
Without all these features, McGyver ventilators are nothing but extremely short-term solutions. Using them for anything longer than a day would actually cause more harm to patients than the virus itself! For a prototype ventilator that checks many of the boxes above, look no further than NASA’s emergency device
A ventilator is nothing without a person in charge
With factories around the world retooled to manufacture professional ventilators, it’s likely that the acute shortage of ventilators observed in the previous weeks will not happen again. Meanwhile, the world should focus on a much more pressing issue: the personnel that can actually make the most out of ventilators (intensive care physicians, respiratory therapists and nurses) is rapidly put out of action. Whether it is extreme burnout or actually coming down with the virus, the world may end up with too many ventilators, and not enough humans who know how to use them!