3D Printed Multi-Patient Ventilator Adapter

The 3D printing of an adapter to connect multiple patients to single ventilator is a concept that has been floating around in the news over the past few weeks. Conceptually, the setup is simple, use two 4-way splitters to connect the inspiratory and expiratory limbs of a ventilator to 4 intubated patients. Although the implementation and management of patients ventilated in this manner is not as simple. The first mention of this concept comes from a 2006 article from the Journal of Academic Emergency Medicine entitled “A single ventilator for multiple simulated patients to meet disaster surge.” The first reported implementation occurred in 2017 when Emergency Physicians at Sunrise medical center in Las Vegas successfully placed two patients on a single ventilator after an influx of intubated patients overwhelmed their ED during the Las Vegas Shootings.

Currently, at least one hospital in New York is attempting to place multiple patients on single ventilators during the COVID-19 crisis. It seems unlikely that this technique will be successful in patient with severe lung disease; however, there are groups that are working on more complex valve systems to make the process function better.

Here is my video discussing the 3D printing of a simple Multi-Patient Ventilator adapter:

Here is a great article from PulmCrit discussing the mechanics of performing multi-patient ventilation:

The General Public Does Not Understand How Surgical Gloves Work.

A large pet peeve of mine is seeing the general public use surgical gloves incorrectly as a means of infection control and protection. I most commonly see gloves being worn by grocery checkout attendants and by law enforcement. Gloves offer little direct protection from day to day interactions and provide a false sense of security that prevents the wearer from performing hand hygiene as frequently as they should.

In order to protect oneself and prevent the spread of infection, an individual needs to clean their hands between each interaction with a new individual. The typical use of gloves by non-medical individuals involves continuing to wear the same gloves for hours or even days at a time. Every time the wearer touches a new surface, object, or person, their gloves pick up whatever was there; when they touch the next surface, object, or person with those gloves, they transfer it and facilitate the spread of disease.

In addition to spreading the disease to others, most people subconsciously touch their clothing and face constantly throughout the day and since they have interacted with hundreds of people with their gloves, its like hundreds of people have touched them.

When I care for a patient in the operating room I use hand sanitizer, don gloves, interact with my patient or dirty equipment, remove my gloves, then use hand sanitizer again before I can interact with a clean environment again. Although we seem pretentious when we do it, we should constantly be reminding the people that wear gloves in public, to change their practice. Grocery workers and law enforcement such as the TSA are facilitating the spread of disease to countless people every day though ignorance of basic hand hygiene techniques.

Here’s a video I made addressing similar concerns over every day, seeing dozens of people wearing surgical gloves in public during the COVID-19 crisis:

3D Printed HEPA Filter Adapter for 3M 6000 Series Respirators

**Disclaimer: Personal protective equipment (PPE) for use in the medical field is extensively tested and FDA approved; any non-FDA approved PPE should be used only in emergency situations when no FDA approved device is available. The information provided here should be considered educational in nature and not medical advice.

The spread of COVID-19 in the US has revealed a severely inadequate supply of personal protective equipment, especially N95 masks. The dwindling supply has lead some healthcare providers to search for creative solutions for respiratory protection. One emerging method is to purchase a reusable 3M 6000 series respirator for use in the hospital environment, however, the cost of replacement filters is high and availability of all N95 filter types is low. With the CDC currently recommending that masks be disposed of after every COVID patient interaction, the cost and availability of replacement filters makes use of these masks impractical.

Small HEPA filters are inexpensive, in high availability, and filter 0.3 micron particles with greater efficiency (> 99.9 %) than N95 masks (95%), making them at least as safe as CDC recommended masks. To utilize these filters I designed and 3D printed an adapter cassette to use inexpensive Roomba vacuum HEPA filters with a 3M 6000 series respirator. With the filter, PLA Filament, and silicone sealant, the final product comes to a total of about $3 each. I also propose that one mask port be capped with a 3D printed cover so only one filter needs to be used with each patient interaction.

In this video I discuss the design, assembly, and testing of a 3D printed cassette to adapt inexpensive HEPA filters to a reusable respirator:

If you would like to replicate this project here are the items that you will need:
1. Filter Cassette 3D Models
2. 3M 6000 Series Respirator
2. HEPA Filters
3. Silicone Sealant
4. Quick drying adhesive

List of tools that you will need:
1. 3D Printer
2. Clamp