(DURHAM, NC) A clinical trial led by Duke University School of Medicine casts doubt on the effectiveness of specialized breathing tubes to prevent pneumonia in patients who need emergency intubation, a life-saving procedure often depicted on medical dramas like “9-1-1," and “The Pitt.”
Specialized endotracheal tubes (ETTs) did not significantly outperform standard breathing tubes or improve patient recovery, according to results of the PreVent2 trial published Nov. 27 in Lancet Respiratory Medicine.
The findings could shift hospital practices and influence national guidelines on which breathing tube to use in emergency situations when patients struggle to breathe on their own.
“These specialized tubes were designed to reduce the risk of ventilator-associated pneumonia, but in the emergency setting, we didn’t see an added benefit,” said the study’s lead author Miriam Treggiari, MD PhD, an anesthesiologist and critical care specialist at Duke Health.
What are these tubes — and why do they matter?
The tubes in question are called PU-EVAC. They use a soft, flexible cuff and built-in suction channel, called a subglottic port, to prevent bacteria-laden fluids from leaking from the mouth and back of the throat into the airways — a major cause of ventilator-associated pneumonia (VAP).
VAP is a dangerous lung infection that can be fatal, especially in patients on breathing machines for long periods of time.
In theory, PU-EVAC tubes offer extra protection. But the new research found that, in the unpredictable environment of emergency care, the benefits did not hold up.
"These findings compel us to continue our search for better strategies to improve outcomes for patients who require mechanical ventilation. But it is clear the answer does not lie with ... subglottic secretion drainage," according to an accompanying editorial.
What the study found
Researchers enrolled 1,074 adult patients at Oregon Health and Science University and Yale New Haven Hospital who required intubation for acute respiratory failure. Half received the specialized PU-EVAC tube, while the other half got standard polyvinylchloride endotracheal tubes.
The trial was funded by the National Institutes of Health and led by Treggiari, and N. David Yanez, PhD, a professor in the Duke Department of Biostatistics and Bioinformatics and a member of the Duke Clinical Research Institute.
Here’s what they discovered:
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Infection rates were similar: 6% of patients using the specialized PU-EVAC tube developed suspected VAP, compared with 5% using the standard tube — not a meaningful difference.
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Overall infections: 8% with the special tubes versus 6% with standard ones.
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Long-term recovery: Among survivors, there were no big differences in throat injuries, thinking and memory problems or overall quality of life.
The trial followed patients for six months. About half did not survive and those who did had serious memory and decision-making issues similar to what is observed in patients with dementia.
The trial was conducted under special emergency research rules that allowed enrollment of critically ill patients without prior consent. While this allowed for a real-world, diverse snapshot of emergency care, it led to challenges in follow-up. Eighteen percent of patients declined to participate in later assessments.
Only 157 patients completed the six-month follow-up, making it hard to draw firm conclusions about quality of life or neurological outcomes.
The bigger issue: critical illness
Even with its limits, the study is the most in-depth look yet at breathing tubes used in emergency care, and its results could guide care across the country.
The U.S. Centers for Disease Control and Prevention say hospitals should consider using the specialized tubes for patients expected to need intubation for more than two or three days. But updated guidance from the Society for Healthcare Epidemiology of America has backed away from that advice, citing mixed evidence — including results from this study.
Beyond comparing tubes, the study highlights a deeper issue: how hard it can be to care for critically ill patients — and how many patients struggle long after leaving the hospital.
“The goal of this work is to improve outcomes for patients who go through some of the most difficult experiences imaginable,” Treggiari said. “Our findings point to an urgent need to better understand the long-term effects of critical illness.”
Additional authors: Emily S. Sharp, Tetsu Ohnuma, Elaine C. Fajardo, Ani Aydin, Shamsuddin Akhtar, Michael Kampp, Mona Hashemaghaie, Aartee Potnis, Tom Gugel, Jamarc Simon, Lazaro G. Curry, Karen Adams, Bhavin Darji, Soundari Sureshanand, Richard Hintz, Samantha N. Lorzano, and Chanel Johnson.
Funding: National Institutes of Health National Heart Lung and Blood Institute.