Cardiovascular Collapse During Intubation

Cardiovascular collapse is an uncommon but life-threatening complication that can occur during tracheal intubation, specifically within 5 to 60 minutes [1]. Current literature estimates the incidence of peri-intubation cardiac arrest to be between 0.5% and 4.2% [1]. However, some studies have cited the incidence to be as high as 20% to 25% [2]. Cardiovascular collapse is defined as hypotension (systolic blood pressure <65 mmHg), new vasopressor requirement, cardiac arrest, or death [1,2]. Given the seriousness of this complication, it is important for anesthesiologists and other relevant providers to understand strategies for prevention and effective management techniques. 

Relatively little is known about associated risk factors [2]. One 2020 study of 815 patients found that low systolic blood pressure at anesthesia induction, pre-intubation vasopressors, and patient age were independent predictors of cardiovascular collapse during intubation [2]. Similar results were found in a 2022 study that evaluated 5,130 patients [1]. It concluded that patients with systolic blood pressures < 90 mmHg before intubation had a higher risk of peri-intubation cardiac arrest [1]. Cardiogenic pulmonary edema as an indication for intubation and elevated lactate levels were also noted to be independent risk factors associated with cardiovascular collapse during intubation. 

One strategy to identify high-risk patients is to use risk scoring systems, like the Modified Warning Score (MEWS) [3]. MEWS has become a widely adopted clinical tool to identify patients at risk of in-hospital cardiac arrest [3]. To calculate a risk score, it considers routinely collected data, like systolic blood pressure, heart rate, respiratory rate, body temperature, and level of consciousness [3]. A higher score correlates with a higher risk of in-hospital death due to cardiac arrest [3]. 

Various approaches have been proposed to minimize the risk of cardiovascular collapse during intubation. Proper preoxygenation with high-flow oxygen for several minutes before intubation helps to extend the apnea time and improve oxygen reserve [4]. This technique, as discussed in the Journal of Intensive Care Medicine, has been shown to reduce the occurrence of hypoxemia during the procedure [4]. Efforts to ensure a successful first-attempt intubation also reduce the chance of life-threatening complications [4]. Video laryngoscopy allows for better visualization of the airway during intubation and has been associated with a decreased incidence of adverse events [4]. A prospective observational study comparing the use of direct laryngoscopy with conventional Macintosh blade to the video laryngoscope demonstrated that video laryngoscopy significantly increases the first-attempt intubation rate [4]. Therefore, it reduces the incidence of intubation-related complications, including cardiovascular collapse [4]. 

Cardiovascular collapse during intubation remains a rare but serious complication that warrants vigilance and preparedness from medical professionals [1]. By understanding the potential contributing factors and adopting evidence-based mitigation strategies, clinicians can reduce the risk of adverse events during this critical procedure [2,3]. Identifying high-risk patients, optimizing hemodynamics, and employing advanced intubation techniques like video laryngoscopy are essential steps toward improving patient outcomes [4].  

References 

1. Yang, T., Chen, K., Gao, S., & Lin, C. (2022). Risk factors associated with peri-intubation cardiac arrest in the emergency department. The American journal of emergency medicine, 58, 229-234. 

2. Halliday, S., Casey, J., Rice, T. et al. (2020). Risk factors for cardiovascular collapse during tracheal intubation of critically iii adults. Annals of the American Thoracic Society, 17(8), 1021-1024. 

3. Wang, A., Fang, C., Chen, S. et al. (2016). Periarrest Modified Early Warning Score (MEWS) predicts the outcome of in-hospital cardiac arrest. Journal of the Formosan medical association, 115(2), 76-82. 

4. De Jong, A., Myatra, S., Roca, O., & Jaber, S. (2022). How to improve intubation in the intensive care unit. Update on knowledge and devices. Intensive Care Medicine, 48(10), 1287-1298.