BIDMC, LHMC Participate in Multicenter Randomized Clinical Trial Likely To Change Procedure for Patients Requiring Emergency Tracheal Intubation

Trial Identified Method That Prevents Hypoxemia During Emergency Tracheal Intubation

BOSTON – In critically ill adults undergoing emergency tracheal intubation, hypoxemia (low levels of oxygen in the blood) increases the risk of cardiac arrest and death.

In current clinical care, most critically ill adults receive supplemental oxygen prior to the start of a procedure to increase the content of oxygen in the lung and decrease the risk of hypoxemia during the tracheal intubation procedure, a practice known as preoxygenation.

Beth Israel Deaconess Medical Center (BIDMC) and Lahey Hospital & Medical Center (LHMC), both part of  Beth Israel Lahey Health, were investigatory sites in a Department of the Defense-funded trial comparing the two most commonly used methods of preoxygenation prior to tracheal intubation: preoxygenation with noninvasive ventilation and preoxygenation with an oxygen mask. Alon S. Dagan, MD, an emergency medicine physician, was the lead investigator for BIDMC.

The Pragmatic Trial Examining Oxygenation Prior to Intubation (PREOXI) study showed that the noninvasive ventilation method (a way to support breathing by using a tight-fitting respiratory mask connected to a BPAP — bilevel positive airway pressure — machine) reduced the risks associated with the intubation procedure. Prior to this trial, international guidelines stated that preoxygenation with either noninvasive ventilation or an oxygen mask is acceptable — guidance that results of this trial are likely to change.

The multicenter, randomized trial was conducted in 24 emergency departments and intensive care units in the United States. Susan Stempek, MBA, MMSc, PA-C, in the Division of Pulmonary & Critical Care Medicine, was the lead investigator for LHMC.

Critically ill adults undergoing tracheal intubation were randomly assigned to two groups: preoxygenation using noninvasive ventilation or preoxygenation using an oxygen mask.

The investigators hoped that preoxygenation with non-invasive ventilation would prevent hypoxemia during intubation, defined as an oxygen saturation less than 85 percent during the interval between induction and 2 minutes after tracheal intubation.

In the 1,301 patients enrolled, hypoxemia occurred in 57 of the 624 patients (9.1 percent) in the noninvasive ventilation group and 118 of the 637 patients (18.5 percent) in the oxygen mask group. Further, it appeared that by preventing hypoxemia during tracheal intubation, preoxygenation with non-invasive ventilation also prevented cardiac arrest, the most feared complication of tracheal intubation, which occurred in one patient (0.2%) in the noninvasive ventilation group and seven patients (1.1%) in the oxygen mask group.

"It is rare that we find a simple intervention that has such a large and direct impact on patient safety," said Dagan, who led the trial for BIDMC. "These results will make a real difference in the treatment of critically ill patients."

"These findings are of major importance because, when implemented systematically, the incidence of hypoxemia during emergency tracheal intubation will be reduced in a clinically meaningful way," said Stempek, the site principal investigator at LHMC. "Participating in trials like this and acting on what we learn is one way we are improving safety for our patients in across clinical settings."

"More than 1.5 million critically ill adults undergo emergency tracheal intubation each year in the United States," said Jonathan Casey, MD, MSCI, assistant professor of Medicine in the Division of Allergy, Pulmonary and Critical Care Medicine at Vanderbilt University Medical Center and a senior principal investigator in the trial. "Hypoxemia occurs during 10 percent to 20 percent of those tracheal intubations in the emergency department or intensive care unit and may lead to cardiac arrest and death. Our study found that among critically ill adults undergoing tracheal intubation, preoxygenation with noninvasive ventilation decreases the incidence of hypoxemia during intubation compared to preoxygenation with an oxygen mask."

Kevin Gibbs, MD, the first author on the study and a critical care medicine physician at Wake Forest School of Medicine, said, "Applying these results to clinical care by routinely using noninvasive ventilation for preoxygenation before tracheal intubation has the potential to prevent tens of thousands of patients each year from experiencing hypoxemia and cardiac arrest."

The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of the US Government.