Simulations Can Reveal Deficiencies in PPE Coverage

By Linda Carroll

April 02, 2020

(Reuters Health) - Simulations to test the effectiveness of personal protective equipment (PPE) may reveal shortcomings in both the equipment and in the manner that PPEs are used, a new study suggests.

Canadian researchers testing PPEs in an airway-management simulation scenario found the equipment they were using might not adequately protect medical personnel caring for a real patient with COVID-19, according to the report in the Canadian Journal of Anesthesiology.

With the help of a mannequin that could "cough" up a mixture containing Glo Germ powder, the study team ran a series of simulations involving different types of protective attire. The Glo Germ powder is a product designed to mimic the spread of microorganisms.

The powder was brushed onto the surface of the simulation mannequin and also loaded into the mannequin's nostrils. While healthcare providers were working on the mannequin, it coughed up droplets containing the powder. When the providers wore reusable yellow gowns that were permeable to liquid, six out of six had visible soilage on their scrubs beneath their gowns.

During one simulation, an airway assistant wearing a disposable Advancement of Medical Instrumentation level-3 surgical gown showed no contamination of the scrubs beneath the gown, but there was significant contamination on that provider's neck, on the base of the wrist, and on the lower pants and shoes.

"While skin contamination is not a method of transmission for the severe acute respiratory syndrome coronavirus-2 responsible for causing COVID-19, these areas of soilage increase the risk for self-contamination (e.g., during doffing) via mucous membranes," write the authors, led by Dr. Shannon Lockhart, of the department of anesthesiology at St. Paul's Hospital and the University of British Columbia in Vancouver.

The study authors did not respond to requests for comment.

Contamination could also occur while providers disrobed, Dr. Lockhart and her team found. The researchers suggested that the doffing process be adjusted to the types of PPEs used, and it must be practiced, they said.

In their simulations, Glo Germ was found on faces, necks, forearms and shoes after participants disrobed.

The new study underscores the importance of practicing with simulations, said Dr. Jennifer Arnold, a neonatologist and medical director of simulation at Johns Hopkins All Children's Hospital in Baltimore.

"One critical message is that identification of the proper PPE coverage is key to protection and testing this with simulation is a safe and effective way to optimize safety for our clinicians," Dr. Arnold said in an email. "Additionally, this article demonstrates the challenge of performing effective donning and doffing procedures"

Even for a simulation expert, some of the findings were unexpected.

"I was surprised to learn just how much contamination of exposure particles can occur in areas we don't think of covering - the neck, the feet," Dr. Arnold said.

While the article was aimed at anesthesiologists, anyone providing care for patients with COVID-19 can learn from it, said Dr. Paul Phrampus, a professor in the department of emergency medicine and director of the Winter Institute for Simulation, Education and Research (WISER) at the University of Pittsburgh.

"What's nice about it is it informs the entire medical community that when these procedures are being done, you need to pay strict attention to what PPE is recommended and also to the procedures for putting on and, most important, the procedures for taking off since this is when most contaminate themselves."

"As a simulation professional as well as a practicing physician, I would like to continue to advocate for simulation centers to be doing these kinds of studies to inform us as we move forward during these trying times," Dr. Phrampus said.

Dr. Phrampus and his team have been running through simulations themselves.

"All day yesterday and today we were looking at system sequences involved in the intubation of patients - who goes in the room and when, choreographing movements," he said. "We probably ran the drill 20 times to refine the sequences so that we do them better and safer."

SOURCE: Canadian Journal of Anesthesia, online March 27, 2020.