Some Background

Emergency intubation is inherently high-risk, particularly in resource-limited settings. The BARCO study—the first multicenter airway registry in Brazil—aimed to determine the frequency of major adverse events (MAEs) during emergency department intubation and their impact on 28-day mortality. While the findings don’t break new ground, they reinforce a critical, global truth: the peri-intubation period is dangerous. A 2021 international study across 29 countries highlighted this same reality. BARCO builds on that foundation, underscoring the urgent need to improve preparation, planning, and training for this high-stakes procedure.

What Was This Study About?

This prospective cohort enrolled 2,846 adult patients from 18 emergency departments between March 2022 and April 2024. MAEs were defined as any of the following occurring within 30 minutes of intubation:

• Severe hypoxemia (SpO₂ < 80%)
• New hemodynamic instability (e.g., SBP < 65 mmHg, vasopressor requirement)
• Cardiac arrest

Key Takeaway:

A major adverse event complicates one in three emergency department intubations in Brazil, most commonly hemodynamic instability. These events significantly increase the risk of death. First-pass success is strongly protective.

What Did They Find?

• MAEs occurred in 32.3% of intubations.
  • Hemodynamic instability: 20.0%
  • Severe hypoxemia: 12.5%
  • Cardiac arrest: 3.5%
• 28-day mortality was 45.1%
  • With MAEs: 57.6%
  • Without MAEs: 39.2%
• First-pass success was 74.3%
  • First-pass success reduced the risk of MAEs (aOR 0.52)
  • Each additional attempt significantly increased the risk of hypoxemia (aOR 2.28)

Practice-Changing Implications?

Potentially. While observational, this study reinforces several critical concepts:

• First-pass success is protective. Structured training, bougies or VL, and proactive planning should be standard.
• Optimize physiology before you begin. A high shock index and lower pre-intubation SpO₂ were strong predictors of MAEs.
• Checklists work. Their use correlated with fewer complications (aOR 0.75).
• Experience matters. First-year residents performed nearly half of first attempts, and more experienced operators had better outcomes.

Strengths and Weaknesses of the Study

Strengths:

• Large, multicenter design across diverse hospital types increases generalizability, especially in low- and middle-income countries (LMICs).
• Prospective data collection with dedicated observers reduces recall bias.
• Robust statistical methods, including multivariable regression, sensitivity analyses, and use of E-values, enhance credibility.
• Focus on a high-risk, underrepresented population in global airway research.

Weaknesses:

• No post-discharge follow-up, so some mortality data may be underestimated.
• Limited capnography use (22%), which could influence complication detection.
• Operator experience and center volume were not deeply explored, limiting insights into system-level contributors.
• Few anesthesiologists were involved (only 3 first-pass attempts), which limits comparison across specialties.
• Generalizability may be limited to other ED or ICU settings in high-income countries.

Bottom Line

The BARCO study underscores a simple but urgent message: complications are common and deadly, but many are preventable. With better preparation, training, and tools, we can reduce MAEs—even in the most resource-constrained settings.

Want to raise your airway game? Prioritize first-pass success, anticipate potential physiological issues, and never skip your checklist.

Related Learning

If this review sparked your interest, don’t stop here—take your training further by exploring The Physiologically Difficult Airway at The Protected Airway Collaborative. This focused content dives deep into managing the high-risk physiology behind these critical intubations, offering practical strategies to improve outcomes when the stakes are highest. Check it out here: The Physiologically Difficult Airway.