Will EEs Be the Heroes of the Global Ventilator Shortage?

As the coronavirus continues to spread, hospitals around the world face a severe shortage of ventilators that alleviate respiratory distress. New York could be short by about 15,000 ventilators to treat the most severe cases, according to The New York Times. In these uncertain times, even carmakers are starting to make ventilators and face masks to help out during the crisis. 

A quick search of ventilators shows that there are many makers around the world who try to build a basic ventilator using readily available materials or 3D-printed parts. Some of these projects are open source to solicit help from experts and enthusiasts all over the world.

In this article, we’ll briefly look at some of these open-source projects. Some of the projects we assessed in this article include OpenLung BVM Ventilator, the Low-Cost Open Source Ventilator or PAPR, the Rice OEDK Design (or ApolloBVM), and OxyGEN, among others. 

We’ll also take a look at the general challenges that a low-budget open-source ventilator project might face.

 

A Few Open-Source Ventilator Projects

Many of the open-source ventilator projects attempt to achieve a very basic operation: blowing a certain volume of air at a specific rate. This is not all that a commercial ventilator performs. For example, ventilators monitor the patient’s breathing status and adjust the ventilation operation when the patient attempts to recover his or her normal breathing. Although the open-source ventilator projects cannot replace a commercial ventilator, they are still worth discussing.

Many of the open-source projects use a low-cost bag valve mask (BVM) as the core of their design. A BVM is a hand-held device that can provide positive pressure ventilation to patients who cannot breathe. 

 

A bag valve mask. Image used courtesy of Indiamart

 

Normally, the bag of the BVM is manually compressed to push air into the patient’s lungs. However, open-source ventilator projects are trying to devise an automated compression mechanism. An automated BVM can somehow act as a simple ventilator. The image below shows one of these add-on devices that mimics the hand compression of a BVM. 

 

An example of an automated BVM proposed in the ApolloBVM project. Image used courtesy of Rice University

 

This device can specify the breathing frequency (slow, medium, and fast) and the volume of the air that is pushed into the patient’s lungs. Another design based on a similar concept is shown here:

 

Concept from the open-source OpenLung project. Image used courtesy of GitHub and OpenLung BVM Ventilator

 

The following image shows another design that is based on the operation of a low-cost CPAP (continuous positive airway pressure). This project converts the CPAP blower into a rudimentary non-invasive pressure support ventilator.

 

Design based on CPAP devices. Image used courtesy of Github

 

Now, let’s take a look at the general challenges that a low-budget open-source ventilator project might face.

 

Ventilator Design: A Multidisciplinary Project

Building a ventilator is a multidisciplinary project that requires collaborative efforts of medical professionals, electronics engineers, and mechanical engineers.

Sufficient experience in these three fields can significantly accelerate the design and evaluation of the product and lead to a more reliable outcome. In addition to expertise in these fields, a project manager is ideally required to act as a middleman between team members. 

The design team should discuss the different aims and features of the product and determine the most crucial ones. Based on this prioritization, the different design trade-offs can be appropriately dealt with.

The main goal of designing an open-source ventilator is providing patients with a low-cost product suitable for low-resource settings. However, we know that cost is not everything, especially when we are designing a medical device. Without considering different aspects of the design, we might end up with an unsafe product that will only be used as a last resort for a patient who lacks certified equipment.

 

The Challenges of Designing a Medical Device

As Robert Keim discusses in his article on the ethics of an engineer's involvement in treating chronic illness, engineers may feel a lot of pressure when designing medical devices because that product will be used to save the life of a human being. The other side of that coin is that a malfunctioning product could severely harm the patient.

That’s why the product should pass several tests before being commercially available. In fact, medical device manufacturers have to heavily invest in tests and quality control of their products. This investment becomes an important factor in the final product cost. 

In the case of designing a ventilator, a precision synthetic lung along with accurate gas-flow analysis is required to completely evaluate the ventilator performance and hopefully remove sources of malfunction. The synthetic lung should allow us to experiment with a wide range of calibrated lung compliance and airway resistance settings.

 

Adult lung simulator. Image used courtesy of Michigan Instruments

 

Being adjustable, the test lung will allow us to replicate hundreds of healthy and diseased lung conditions. Unfortunately, synthetic lungs and accurate gas flow analyzers are not instruments that most engineers can get their hands on. Not having access to the appropriate instruments poses a challenge for designing a reliable ventilator. 

 

Tight Budget

As discussed above, designing a ventilator is challenging because it is a multidisciplinary project that requires expensive and comprehensive tests. Many of the open-source projects that we find on the internet have a very tight budget. This further reduces the odds of success for these projects. 

 

Open-Source Ventilators: Approve or Discourage?

A commercial ventilator falls around $5,000 at a minimum and is the result of the collaboration of a large group of scientists. Successful brands have heavily invested to improve their designs over the years. They have the time to redesign and debug their ventilators based on the feedback of clinicians using their devices in real-world situations.

Obviously, many of the open-source ventilator projects we find on the internet are not at all comparable with a commercial ventilator. However, I believe that there is merit in building these projects. These are attempts from caring people to alleviate the COVID-19 pandemic and might have the potential to save many lives.

The open-source approach is the fastest and most affordable way to gather and digest the information that is out there. It allows us to share our ideas with experts from other disciplines and learn from each other’s experiences. These projects might not be perfect at this stage but they may inspire us to take action and improve the available designs.  

 

A Life-Saving Endeavor

In this article, we briefly looked at some of the open-source ventilator projects. We also took a look at the general challenges that such low-budget ventilator projects might face.

The design of a ventilator is challenging because it is a multidisciplinary project that requires expensive and comprehensive tests. Many of the open-source projects that we find on the internet have a very tight budget. This further reduces the odds of success for these projects.

However, these attempts are valuable because they aim to solve the severe ventilator shortages in hospitals and may potentially save many lives.

 

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What are your thoughts on the open-source ventilator movement? Have you perused any of these projects yourself? Share your comments below.