Gun victims with massive blood loss and lung failure grabbed the emergency room of the Sunrise Hospital in Las Vegas in the late evening of October 1, 2017. A man opened fire at a music festival on the 32nd floor of the Mandalay Bay Hotel and sprayed more than a thousand rounds of ammunition into the crowd, injuring hundreds.
The hospital soon ran out of ventilators, machines that breathe for patients who cannot. Dr. Kevin Menes, an intensive care doctor, had several respiratory failure patients. Menes remembered that a colleague from his medical training had examined how several people can be connected to a single ventilator. When a respiratory therapist said to Menes, “We have no more ventilators,” I said, “It’s okay,” he later recalled. He asked for tubing and began dividing a machine’s oxygen flow into two patients to save their lives.
Now Menes’ provisional strategy could be adopted by desperate caregivers worldwide. With hospitals assuming that more COVID-19 patients arrive with respiratory arrest than ventilators to which they can be connected, the idea of using a ventilator for two or more patients has received widespread attention and support, even in two well-known hospitals in Manhattan.
However, interviews with intensive care physicians and a review of the medical literature show that connecting more than one person to the same ventilator is an emergency solution that can damage the patient’s lungs. At best, many doctors say, this is a last resort for patients who have stopped breathing on their own and have no other chance of survival.
A ventilator is designed in this way and can only be set for one patient at a time. Because two patients are unlikely to need oxygen at the same amount and pressure, one may get too little oxygen while the other receives too much oxygen, which in both cases will injure the lungs. The air hoses can also distribute contaminants between the patients. Because of these concerns, a major ventilator manufacturer and the American Association for Respiratory Care are preventing hospitals from connecting machines to multiple patients. Some hospitals are reluctant to try and look for other backup plans.
“This is not a panacea,” said Dr. Lewis Rubinson, chief medical officer at Morristown Medical Center in New Jersey and long-time intensive care physician. “We don’t want a solution that distracts, and that’s what it has become.”
Some see it not as a distraction, but as a lifesaver at a time when the U.S. health care system has approximately 160,000 ventilators. Less than half of most statistical models estimate that it is needed to treat seriously ill coronavirus patients. A YouTube video posted by an intensive care doctor in Detroit showing how up to four patients can be connected to a ventilator has been viewed more than 800,000 times in the past 10 days. A doctor in a rural hospital in Canada told reporters that he had doubled the number of patients he could breathe simultaneously by following the video’s instructions.
In New York City, where nearly 30% of the country’s coronavirus cases occur, intensive care units at New York’s Presbyterian Hospital and Columbia University’s Irving Medical Center are testing the use of split ventilation, Dr. Craig Smith, the hospitals. Chief surgeon said in a note to the staff this week. Smith praised the plans to provide multiple patients with a ventilator as an important innovation and wrote: “Today, technology forged in the crucible of mass trauma helps our medical colleagues treat COVID-19.”
New York governor Andrew Cuomo approved its use on Tuesday. “We go so far as to try an experimental process where we split the ventilators,” he said. “We use a ventilator for two patients. It’s difficult to do, it’s experimental, but we currently have no alternatives. “
Some hospitals are about to run out of ventilators. A New Jersey intensive care doctor who refused to identify herself or her employer said the facility was treating dozens of patients who had tested positive for COVID-19 while several dozen others were waiting for test results. A young patient arrived and tried to breathe. “Suddenly there was panic about where we would get the next ventilator from,” said the doctor. Finally a ventilator for the child was found.
A ventilator pumps oxygen into a patient’s airway when the lungs are too injured or sick to breathe alone. In COVID-19 patients, doctors and respiratory therapists usually first put tubing into the airways to provide oxygen to the lungs. Then they determine how often the machine breathes for the patient and how much oxygen it sends. Using sensors, the ventilator tracks everything about the breaths – their length, the resistance that the air exerts in the body, and how much the lungs expand and contract. Healthcare professionals use the information to determine if treatment is working and to make adjustments.
When multiple patients are connected, a ventilator becomes a blunt instrument. The tubes are set so that the air that the ventilator pumps out is divided into two or four tubes, each of which goes into a different set of lungs. It moves air in and out of every person, or at least tries. Doctors and therapists need to carefully choose which patients to mate and match them based on gender, height, and diagnosis.
This is very inaccurate, said Rubinson. Sick patients whose lungs are more resistant absorb less oxygen. Stronger patients take in more air, which can lead to their own problems. The machine cannot be adjusted and it is difficult for the intensive care staff to do so.
Early studies of whether ventilators could work on more than one patient included tests on artificial lungs that simulate the function of the actual lungs. In 2006, two emergency physicians at St. John’s Hospital and the Detroit Medical Center determined that one ventilator might not be available to provide a “major botulism outbreak” or other disaster for hospitals several artificial lungs would have enough ventilators, but could not determine whether there was sufficient oxygen or whether lung injuries were possible. A follow-up study in animals found that ventilators had difficulty distributing air evenly. There has never been a controlled human test.
The shortcomings are well known in most intensive care units. Even hospitals that include technology in contingency plans for COVID-19 plan to use it only as a last resort. “In a short-term scenario, this would be a potentially life-saving decision,” if a hospital runs out of ventilators, said Dr. Gregory Martin, head of intensive care at Grady Memorial Hospital in Atlanta.
“However, there is no way to decide how much oxygen or how much carbon dioxide to remove, or what size of breath to give to multiple patients on one ventilator,” Martin continued, adding, “We would not use this solution if we were really others Would have opportunities. “
At the University of California, San Francisco, intensive care units are working on ways to deal with a deficiency and avoid using multi-patient technology, said Dr. J. Matthew Aldrich, Executive Director for System Intensive Care. It has not been proven and “I am not aware of a successful deployment in such a situation.”
Anesthesia equipment in operating theaters has built in ventilators that could sometimes be used to treat intensive care patients, Aldrich said.
The American Association for Respiratory Care, which represents more than 40,000 respiratory therapists, is preventing hospitals from connecting two or more patients to a single ventilator, said Tim Myers, a senior executive at the association. The technique does not allow caregivers to ensure that patients receive the correct amount of air or to track their breathing.
“How do we know your lungs are getting better?” Myers said.
Hamilton Medical AG, one of the largest ventilator manufacturers, warns against multi-patient technology. “Ventilators use sensors to adapt ventilation to each individual patient. This is important in critically ill patients – like COVID-19 patients, ”said a spokeswoman for Hamilton Medical in a written response to questions. “If a ventilator had multiple patients, who should the ventilator adapt to?”
When a patient’s lungs resist airflow, they migrate to the other patients, who then receive more than their lungs need, and possibly more than they can tolerate, said Audrey Mak, a retired respiratory therapist in southern Texas.
“Suppose you have a balloon and you blow it all the way, the balloon is getting weak,” said Mak. “You can do the same with your lungs.”
Maya Miller contributed to the reporting