Tracking a New Way to Prevent Ventilator-Associated Pneumonia
Healthcare-associated infections come in so many forms, affecting so many different populations of patients, that it can be difficult to come up with comprehensive plans to address each and every one. Some common types include urinary tract infections and surgical-site infections, both of which can introduce dangerous (not to mention expensive) complications when a patient is trying to get back on their feet following a procedure or a hospital stay.
Another healthcare-acquired infection that wreaks havoc on patients is ventilator-associated pneumonia. As the name suggests, ventilator-associated pneumonia, or VAP, is “associated with prolonged duration of mechanical ventilation and ICU stay.” A study published in the NIH’s PubMed Central database sought to provide a high-level overview of VAP, examining its rates, prevention methods, diagnosis and treatment, and more. The authors wrote that “prevention of VAP is based on minimizing the exposure to mechanical ventilation and encouraging early liberation.”
Incidence rates “vary greatly based on the studied population,” seeming to affect patients with cancer and major traumatic injury more than other populations, as well as those with COPD. Steps taken to diagnose the disease begin with clinical suspicion, and a number of scores have been suggested in an attempt to make diagnosis more precise. The most common diagnostic tool for VAP is the “Clinical Pulmonary Infection Score,” or CPIS, but studies have found that using this tool “may be associated with undue antibiotic use due to its low specificity.” Another issue in diagnosing the disease is that many of the criteria used to identify VAP are not specific, and “can often be observed in the many conditions that mimic VAP.”1
VAP can also lead to more severe outcomes in patients. A study in Nature Communications said that “reported mortality rates for VAP span a wide range (24–76%); however, attributing mortality solely to VAP is complex due to the severity of underlying illnesses and diagnostic heterogeneity within ICU populations. VAP can lead to the development of septic shock or acute respiratory distress syndrome if the treatment is delayed or inappropriate. VAP results in substantial antibiotic prescription pressure, accounting for half of all antibiotics used in the ICU.” However, “the prolific use of antibiotic therapy contributes to a vicious cycle of increasing multidrug-resistant (MDR) pathogens and mortality. Treatment failure increases the risk of mortality and may occur in a third to two-thirds of VAP cases, with inappropriate antibiotic use the most common cause.”2
As mentioned earlier, the surest way to prevent VAP is to attempt to move the patient out of intubation as quickly as possible, or to use less-intensive methods. However, since that’s sometimes simply not an option, it is imperative to search for other ways to reduce incidence rates of the disease. Enter a team from Michigan Medicine, who developed a “soft, antimicrobial mouthguard that absorbs secretions before harmful bacteria can reach the lungs.”3
Healthcare Purchasing News reached out to Michigan Medicine and was able to speak with Dr. J. Scott VanEpps, MD, PhD, associate professor of emergency medicine, University of Michigan Health, who was part of the interdisciplinary team that developed the mouthguard.
How significant of a threat does ventilator-associated pneumonia pose to patients?
VanEpps: 1 in 10 patients on a ventilator will get ventilator-associated pneumonia. That comes out to over 75,000 patients each year.
Who is most at risk of acquiring a severe case of VAP?
VanEpps: The risk of VAP increases each day the patient remains intubated and on mechanical ventilation. Other risks include patients with immune suppression or prolonged hospitalization.
How does the mouthguard work to prevent VAP?
VanEpps: Bacteria-laden saliva pools in the back of the throat, forms biofilms on the breathing tube, and ultimately leaks into the lower respiratory tract causing pneumonia. Most of the bacteria come from the gingiva, or gums. The mouthguard reduces the risk of VAP by absorbing that saliva from around the gingiva and teeth and rapidly killing the bacteria. In essence the device captures and kills VAP causing bacteria in the oral cavity before they reach the lungs.
How was the mouthguard workshopped and how did the idea come about?
VanEpps: The mouthguard was developed by combining the ideas of absorbing the saliva that carries the bacteria to the lungs and the rapid killing of the bacteria in place.
Are human trials forthcoming / have they happened already?
VanEpps: We are designing the first human trials now.
Does the mouthguard hold potential for working to prevent other HAIs?
VanEpps: While VAP is the most expensive HAI to treat, the mouthguard could immediately be leveraged to reduce healthcare-associated pneumonia even in patients without breathing tubes or respirators. More broadly, the material science used in the technology could be adapted for other medical devices such as catheters or prosthetics.
Are the mouthguards easily sterilized? How can patients be protected from infections spread by the mouthguard itself?
VanEpps: The mouthguards come sterilized like any other medical device. However, they are disposable. Specifically, they are placed in the mouth for only 12 hours and then replaced with a fresh one.
How does the timeline look for integration in hospitals / with patients?
VanEpps: We anticipate completion of first clinical trials and obtaining FDA approval in 2-4 years.
Another Michigan Medicine Development
At the Weil Institute at the University of Michigan, researchers are developing other tools to help prevent infections across the healthcare spectrum beyond healthcare-associated infections. Another such tool, the so-called “Micro-Gas Chromatography” or Micro-GC, utilizes a breathalyzer-type device to enable rapid COVID diagnosis at the bedside.
This device is backed by studies that affirm its efficacy. The team was granted a “$2 million grant from the National Institutes of Health to test their device’s ability to detect and monitor COVID-19 breath markers. They defined four sets of VOCs [volatile organic compounds] that were able to distinguish between COVID-19 and non-COVID illness. However, when the team applied the same VOCs in a setting of presumed [Covid variant] Omicron, sensitivity decreased drastically. They undertook additional biomarker searchers and defined new VOCs to discern between Omicron and Delta, Omicron and non-COVID illness, and between patients with COVID-19 and non-COVID illness regardless of variants.”
The tool was able to “detect COVID-19 infected patients (regardless of variant) from non-COVID patients with a sensitivity of 89.4%, a specificity of 91.0%, and an accuracy of 90.2%. This performance was shown to be close to that of RT-PCR tests (the gold standard) and better than many rapid antigen tests.”4
This same technology was later expanded to include a diagnostic tool to “quickly and accurately diagnose acute respiratory distress syndrome (ARDS) and subsequently track its progress.” By using the breathalyzer-type device, the researchers hope to “gain fundamental insights into the presence and dynamics of VOCs/VICs in exhaled breath which present as inflammatory and metabolic markers of ARDS pathophysiology. Most importantly, the portable GC technology will bring molecular diagnostics to the bedside, enabling earlier initiation of ARDS treatments that improve outcomes, as well as novel trajectory monitoring to inform prognosis and downstream critical-care decision-making.”5
Again, there are so many massively prevalent conditions and infections to prevent against that it feels overwhelming in the aggregate. Faced with so many different ailments, however, innovation continues to ensure specific and simple care and treatment, making the lives of clinicians and their patients easier.
References:
-
Papazian, Luther, et al. "Ventilator-associated pneumonia in adults: a narrative review." Intensive Care Medicine. Mar 2020. https://pmc.ncbi.nlm.nih.gov/articles/PMC7095206/
-
Howroyd, Fiona et al. "Ventilator-associated pneumonia: pathobiological heterogeneity and diagnostic challenges." Nature Communications. July 2024. https://www.nature.com/articles/s41467-024-50805-z#Sec1
-
Jimenez, Danielle. "Stopping a $40,000 infection with a $40 device." https://www.michiganmedicine.org/health-lab/stopping-40000-infection-40-device
-
"Meet Micro-Gas." MAX Magazine. Spring 2024. https://issuu.com/weil-institute/docs/max_magazine_-_spring_2024/9
-
Murphy, Kate. "U-M Team receives NIH grant for collaborative research to speed ARDS diagnosis." https://medresearch.umich.edu/news-release/u-m-team-receives-nih-grant-collaborative-research-speed-ards-diagnosis