Identifying modifiable variables to reduce the risk of patient cardiovascular collapse during emergency intubation

Tracheal intubation is a high-risk procedure commonly performed in critically ill patients who are suffering from severe respiratory problems and requiring support to breathe.

The International Observational Study to Understand the Impact and Best Practices of Airway Management in Critically Ill Patients (INTUBE) was conducted to gain a better understanding of the complications experienced by critically ill patients undergoing intubation in intensive care units (ICUs), emergency departments and wards.

INTUBE is the largest study of intubations in critically ill patients ever conducted, including 2964 patients, from 197 sites, in 29 countries across five continents.

Cabrini researcher Associate Professor David Brewster (pictured), Deputy Director of Intensive Care at Cabrini Health and the Clinical Dean for the Monash University Clinical School, was the national coordinator for the INTUBE study in Australia and New Zealand, and a co-author of the publications.

The INTUBE 2021 JAMA publication put a spotlight on the severity and frequency of intubation complications. Concerningly, the results showed more than 40% of patients suffer a lifethreatening complication during intubation. A new publication from the INTUBE study has now looked further into periintubation cardiovascular instability/collapse events (events occurring within 10 minutes of intubation), the predominant complication experienced by patients undergoing emergency intubation in the original JAMA study.

Cardiovascular instability/collapse covers a broad range of medical events, defined as sudden loss of effective blood flow due to cardiac and/or peripheral vascular factors that may reverse spontaneously (e.g. vasovagal syncope) or require an intervention (e.g. cardiac arrest).

The new INTUBE study outlines that peri-intubation cardiovascular instability/collapse was an extremely common occurrence, experienced by 1199 of 2760 patients (43.4%), and placed patients at almost a triple risk of death in ICU or within

28 days of an ICU stay. To identify variables that could be modifiable to improve outcomes, they characterised the most common factors that were associated with cardiovascular instability/collapse events. Risk factors were found to be older age, higher heart rate, lower systolic blood pressure, lower oxygen saturation as measured by pulse oximetry/FIO2 before induction and the use of propofol as an induction agent. While many of these factors are not modifiable, the use of propofol is a potentially modifiable intervention. Propofol is a common sedative agent known to provide excellent intubation conditions without the use of neuromuscular blocking agents. The current study suggests that using propofol to intubate critically ill patients should be reconsidered.