A multi-institutional survey of current practices in critical care airway management has found that, among other revelations, video laryngoscopy is the primary choice as both the initial and backup device for routine and difficult airway management.
“Video laryngoscopy devices seem to be the primary modality chosen when it comes to airway management in the intensive care unit, and post-intubation low blood pressure is a frequent occurrence that is associated with poor outcomes,” Nathan Smischney, MD, an anesthesia intensivist at Mayo Clinic, Rochester, Minn., and the lead author of the study, said about the findings. Dr. Smischney presented the results at the Society of Critical Care Medicine’s (SCCM’s) 2016 Critical Care Congress (abstract 80).
What Is ICU Intubation Practice?
The purpose of the survey was to get some sense of institutions’ airway management and hemodynamic control strategies during intubation. Characterization of current ICU intubation practice is largely unknown, and intubation carried out in the ICU as compared with other settings can be associated with increased complications, the researchers explained, noting that critical care airway management cases experience high rates of cardiac arrest.
A nationwide representative group of clinicians performed a standardized 23-item survey. All data were obtained from the clinical providers at the 25 participating sites that actually performed the intubations. Respondents were asked about airway and hemodynamic management of intubations. Eleven sites responded: Minnesota, Wisconsin, Nebraska, Ohio, Arizona, Florida, North Carolina, Pennsylvania, Rhode Island, Massachusetts and Washington.
James DuCanto, MD, director of the Simulation Center at Aurora St. Luke’s Medical Center in Milwaukee, who was not involved in this study, commented that the airway management practices reflected in the survey were mixed.
For instance, most responding institutions (88%) have not adopted the use of checklists before invasive airway management, although the use of such checklists is now considered “state of the art,” Dr. DuCanto said.
“The use of checklists has not entered the culture of the critical care units surveyed to any great degree, despite recommendations of the WHO [World Health Organization] to utilize these cognitive aids to reduce medical errors,” Dr. DuCanto said. “The survey results suggest that the critical care units surveyed do not utilize the ASA [American Society of Anesthesiologists] difficult airway algorithm, nor the recent Difficult Airway Society algorithm, despite the simplicity and great utility of these algorithms.”
Role of Supraglottic Airway
“These algorithms suggest the use of supraglottic airways in the event of a failed intubation attempt as a method to reduce or eliminate the occurrence of critical hypoxemic events, which can also contribute to severe hypotensive events as well. The supraglottic airway can be utilized as a conduit for tracheal intubation as well,” Dr. DuCanto said. “The 20% of survey respondents who mentioned the use of flexible fiber optics may actually be utilizing supraglottic airways in many of those case scenarios.”
On the other hand, more than half (69%) of respondents reported a first attempt with video laryngoscopy equipment, which he called an important trend. When a difficult airway is encountered and the primary device has failed, 40% use video laryngoscopy followed by fiber-optic bronchoscopy (20%). Only 38% routinely practice cricothyroidotomy.
“This survey demonstrates a positive trend across United States critical care units for the use of video laryngoscopy for the initial first-pass attempt at airway management, and furthermore demonstrates the use of these devices for second attempts following a failed first attempt,” Dr. DuCanto said.
Ketamine and Propofol Preferred
The researchers also found that although most centers use etomidate and propofol for induction, most providers prefer to use ketamine and propofol. “This may be related to the finding that hypotension was the most common immediate complication indicated, with recent studies showing value in a ketamine-propofol admixture (“ketofol”) regarding a patient’s hemodynamic status,” said Dr. Smischney. “Ketamine and/or ketofol may have a role in preventing [hypotension]; thus it may be a preferred agent in this population.”
Regarding hemodynamic management, etomidate is used the most (100%) followed by propofol (90%), with fentanyl (88%) and midazolam (88%) as the most common adjuncts. However, most respondents preferred to use ketamine (90%) followed by propofol (90%), with a similar proportion of respondents using the above adjuncts. Ninety percent of respondents listed hypotension as the most immediate complication, with 55% using vasoactive agents.
Although the survey did not address why providers are not using ketamine even though they prefer it, Dr. Smischney said: “One could speculate that perhaps drug shortages/costs and lack of studies showing benefit of ketamine in ICU patients could be playing a role.”
Dr. Smischney said this finding was particularly relevant, as some evidence indicates worsened survival when etomidate is used for intubation in the critically ill.
“Choices regarding induction medication are largely based upon the combination of etomidate, fentanyl, propofol and midazolam,” Dr. DuCanto said. He noted that a general interest in the use of ketamine to improve intubating conditions and reduce the negative hemodynamic effect of sedative medication is in the “collective conscious” of the critical units surveyed. He said that mirrors international trends.
“If more studies are conducted on ketamine within the critically ill, more providers may be willing to use the medication, which may in turn translate into improved outcomes,” Dr. DuCanto said.
The most common reason for intubation was acute respiratory failure (76%), according to the researchers.
“Post-intubation hypotension has recently gained attention and has been shown to be associated with increased mortality,” Dr. Smischney said. “Several risk factors have been identified through the various studies, with some indicating certain medications as a risk factor. However, we are far from knowing the exact mechanisms at play.”
Dr. Smischney said efforts are underway to investigate the peri-intubation period more thoroughly among the critically ill, with more than 15 centers involved in the United States (see www.hemairregistry.org). “The investigators envision the creation of a national registry to better understand both hemodynamic and airway management in the ICU so as to improve the care delivered during this process.” The HEMAIR (HEModynamic and AIRway Consortium) study hopes to enroll 1,000 or more patients, with more than half already enrolled, he said.
Terming the study presented at SCCM “exploratory,” Dr. Smischney said making any recommendation is difficult because causation has not been demonstrated. “ However, the results indicate that more research needs to be done in this area, especially since post-intubation hypotension is common and recent studies have suggested a link between this and mortality in both the ICU and operating room,” he said.