As hospital administrators and public health officials scramble to meet a shortage of ventilators for Covid-19 patients, teams of doctors, engineers, and DIYers are filling some gaps by modifying breathing machines that are relatively plentiful, such as those used to treat sleep apnea. This technological fix is happening at the same time as a bubbling medical debate among physicians over whether too many coronavirus patients are being placed on traditional ventilators that some argue may do more harm than good.
A team of UC Berkeley engineering students designed and built a conversion kit to retrofit several thousand sleep apnea machines that have been donated to a volunteer group in the Bay Area called Ventilators SOS. The modified devices are helpful for patients who are improving or have milder symptoms, saving ventilators for severely ill patients who are battling advanced respiratory failure.
Plus: What it means to “flatten the curve,” and everything else you need to know about the coronavirus.
“This is a simple device,” says Ajay Dharia, a pulmonary specialist at Mills Peninsula Medical Center in Burlingame, California, who is helping coordinate the volunteer effort along with medical researchers and technicians at UC Berkeley and UCSF. “The type of patient for us to treat is someone with milder disease or people who have been on a ventilator for a long time and are recovering. If someone who has been on a ventilator for 14 days, which is what we are seeing now with many patients, and you can shorten it to 10 days, then someone else can use the ventilator.”
Meanwhile, Massachusetts General Hospital in Boston and Emory University Medical Center in Atlanta are also modifying sleep apnea machines to prepare for an expected shortage of ICU ventilators. Emory is preparing for an April 20 projected peak of coronavirus patients, and is facing a shortage of somewhere between 500 to 1,000 ICU beds in the Atlanta area, according to Chris Martin, a pulmonary care physician at Emory University School of Medicine. While they don’t need any extra ventilators right now, they are preparing by converting some sleep apnea machines. “We realize that we need to adjust and adapt,” Martin says. “We have gone through the process to inventory and make sure they are ready and have all the supplies and connectors.”
Devices that have already been approved for hospital use, such as anesthesia and sleep apnea machines, don’t need extra certification to treat Covid-19 patients, according to an FDA emergency use authorization issued March 24.
There are two types of sleep apnea machines. The bi-level positive airway pressure, or BiPAP, machine pushes oxygen into the lungs of patients through a face mask or nose tube. Carbon dioxide is removed from the lungs at a lower pressure level, making it easier for patients to breathe at night. A second kind of device, the constant positive airway pressure (CPAP) machine, only has one pressure setting and is less flexible, but is also smaller, cheaper (about $500), and easier to use. In contrast, a mechanical ventilator typically used in a hospital to help patients in respiratory distress uses a flexible tube placed inside the throat to fill the lungs with air and in effect breathe for the patient. It can cost upwards of $50,000.
Read all of our coronavirus coverage here.
As the epidemic has gripped New York, several hundred coronavirus patients are crammed inside Mount Sinai’s intensive care units, surgical suites, and regular hospital rooms. Tesla founder Elon Musk sent several hundred BiPAP machines to the hospital in late March, and Dr. Hooman Poor, a pulmonary and critical care physician at New York’s Mount Sinai Medical Center, was part of a team that figured out how to reconfigure them with a few off-the-shelf parts. They added a filter to the exhaust valve so virus particles expelled from the patient’s lungs don’t endanger hospital workers and an alarm system to warn nurses when a patient might be in trouble.
Poor says they haven’t yet had to deploy modified sleep apnea machines turned ventilators, but just knowing they are ready is a big relief. “The one situation that terrifies me is having to make a decision with two patients and one ventilator and having to decide who gets it,” says Poor. “Having these extra machines reduces the chance I would have to make that decision.”
Hospitals in New York, Chicago, and Boston are also repurposing anesthesia gas machines that are normally only used during surgical procedures, according to Mary Dale Peterson, president of the American Society of Anesthesiologists and a pulmonary pediatric physician at Driscoll Children’s Hospital in Corpus Christi, Texas.
Peterson says that many hard-hit hospitals are doing the best they can as ventilators run short, but we shouldn’t forget that medical workers need to be trained on new machines, or repurposed ones. “Under normal conditions, you would want enough time for enough testing and vetting, time to train the staff on how to manage those ventilators, because on every piece of machinery you have to learn where the buttons are,” Peterson says. “But we are not dealing with ideal conditions. I’m hoping we are getting through the crisis without having to resort to things that are totally brand new or haven’t been tested.”
The ventilator shortage has also attracted novel designs that still must get approval from the FDA before being used on patients. A Mississippi doctor built a breathing bag from parts he bought at a local hardware store, while a team of Rice University engineering students designed an automated breathing bag that can be used by first responders or emergency room doctors that can be built with 3D printed parts for about $150.
“Maybe you have a hospital that runs out of ventilators, or someone in an ER needs to be intubated,” says Rohith Ramachandra Malya, an assistant professor of medicine at Baylor School of Medicine who advised the Rice University students. “Rather than pulling someone off an existing ventilator, this device buys you time.”
At the same time that doctors and engineers are coming up with new breathing machine designs, some medical experts are beginning to question whether doctors are putting too many coronavirus patients on hospital ICU ventilators. In social media and online discussions, some emergency medicine physicians suggest that existing Covid-19 protocols may need to change and that with some patients, ventilators may do more harm than good. They say that some patients have low blood oxygen levels that trigger the use of a ventilator according to existing medical protocols, even if the patients are not gasping for air or having heart problems.
This debate played out this week on an episode of the MedScape podcast, in which John Whyte, chief medical officer of the WebMD website interviewed New York emergency room physician Cameron Kyle-Sidell. Kyle-Sidell said he’s noticing that many of his coronavirus patients are in a state of hypoxia, or low oxygen, a condition similar to what happens to hikers or skiers who get altitude sickness. Most of the time, when patients hit that level of hypoxia, they can barely talk, but he spoke about a patient who could, and who said she did not want a breathing tube.
“So she asked that we put it in at the last minute possible,” Kyle-Sidell said during the MedScape podcast interview. “It was this perplexing clinical condition: When was I supposed to put the breathing tube in? When was the last minute possible? All the instincts as a physician—like looking to see if she tires out—none of those things occurred. It’s extremely perplexing. But I came to realize that this condition is nothing I’ve ever seen before.”
Kyle-Sidell noted that a group of Italian ER doctors had also described this phenomenon in a March 30 letter to The American Journal of Respiratory and Critical Care Medicine describing Covid-19 patients who had functioning lungs and could still breathe on their own, but who were suffering from low oxygen levels that could kill them. Kyle-Sidell and the Italian doctors both argue that it might be better to avoid putting Covid-19 patients on a ventilator for as long as possible, and use sleep apnea machines instead. Ventilators work by forcing air into the body under pressure. Over time, this pressure eventually damages tiny air sacs in the lungs, and can harm the patient just as much as the coronavirus that is attacking the entire respiratory system.
In New York, city health officials reported this week that 80 percent of Covid-19 patients placed on a respirator have died, according to the Associated Press. In Seattle, only one of the seven patients older than 70 who were put on a ventilator survived; just 36 percent of those younger than 70 did, according to a study published last month in The New England Journal of Medicine by researchers from the University of Washington, the Fred Hutchinson Cancer Research Center, the Virginia Mason Medical Center, and the Swedish Medical Center, all in Seattle.
Less-invasive machines, such as the BiPAP or anesthesia devices, may be a solution for patients whose lungs are not completely destroyed by Covid-19, but still need to maintain oxygen levels. At the same time, Poor says he and other frontline medical workers know they don’t have all the answers. “There isn’t a magic pill,” says Poor. “Hopefully we can figure out this disease better, because I can tell you we don’t understand this disease.”
WIRED is providing free access to stories about public health and how to protect yourself during the coronavirus pandemic. Sign up for our Coronavirus Update newsletter for the latest updates, and subscribe to support our journalism.
More From WIRED on Covid-19
- Why are some people getting so sick? Ask their DNA
- New Yorkers, once again at ground zero, in their own words
- Un-miracle drugs could help tame the pandemic
- WIRED Q&A: We are in the midst of the outbreak. Now what?
- What to do if you (or a loved one) might have Covid-19
- Read all of our coronavirus coverage here