Checklists for Tracheal Intubation of Critically Ill Adults

Checklist use is almost ubiquitous in life, helping us to remember tasks, groceries, and other commonly forgotten items in our daily routine. High-stakes scenarios that involve potential risk, such as piloting an aircraft, include checklists to ensure the consistent performance of agreed-on essential items that are vital for safe operation. Checklists for these items are also performed among multiple people involved in the operation to create an environment of teamwork and communication. Tracheal intubation of critically ill adults is a high-stakes procedure associated with a number of complications, such as cardiovascular collapse¹ and hypoxemia²: has a number of preparatory items experts agree should always be performed; and requires a team to safely perform the procedure.³ This procedural environment has been, therefore, hypothesized to benefit from checklist use.

In this issue, Turner et al⁴ report a systematic review and meta-analysis of 10 observational studies and 1 randomized clinical trial on the association of preparatory procedural checklist use before tracheal intubation of critically ill adults with the primary outcome of mortality. Secondary outcomes included first-attempt success, esophageal intubation, hypotension, cardiac arrest, and hypoxic events. Use of a preintubation checklist was not associated with a reduction in the primary outcome of mortality or any secondary outcome except for a reduction in hypoxic events in all 11 studies. However, this association with fewer hypoxic events was no longer statistically significant when limiting the analysis to studies at low risk of bias.

The authors should be commended on their work and willingness to subject checklist use to research rather than assuming that this intervention works without asking the question. There is no commonly agreed-on primary outcome in tracheal intubation research, with outcomes including first-attempt success, which is likely more proceduralist centered than patient centered, and cardiopulmonary collapse and mortality. Although mortality is often chosen as the primary outcome, it is difficult to understand any biologically plausible mechanism in which a preprocedural checklist to prepare for a 2-minute procedure, on average,^1-3 would have any mechanistic association with mortality. However, the authors also analyzed procedural- and possibly patient-centered outcomes found no consistent association. In addition, the robustness of the meta-analysis was limited by the predominance of observational studies and the exclusion of a commonly cited observational study⁵ of an intubation bundle, which was associated with decreased cardiopulmonary collapse but was not applied in the form of a checklist.

Two consistent patterns exist in the checklist medical literature. First, when added to care environments where there is a low baseline performance of the checklist items, checklists are commonly associated with improved outcomes. Surgical safety checklists⁶ may be the best example of this pattern. Second, when checklists are added to care environments where the performance of the items is already high, an association with improved outcomes is usually not observed.^3,7 How are we to interpret the checklist for tracheal intubation literature and this meta-analysis given these patterns? Checklist use for tracheal intubation in environments where items are already commonly performed probably does not have a large association with procedural- or patient-centered outcomes. What remains unknown is whether the use of a preintubation checklist improves outcomes in limited resource or limited procedural experience environments. This is an important unanswered question because intubation occurs millions of times a year and often in environments without ample resources or experienced operators. It is also unknown which items should be included in a preparatory checklist to improve outcomes. The randomized clinical trial of checklist use for tracheal intubation³ was the only study included in the meta-analysis in which checklist items were created using an iterative process of guideline recommendations, expert recommendations, and consideration of the time-sensitive environment of intubating critically ill adults. In addition, this meta-analysis could not definitively answer the question of whether there is a small association with outcomes such as mortality because the 95% CI for the point estimate of the association of checklist use with mortality included the potential for small reductions or increases in mortality.

Practitioners who hold a prior belief that checklist use improves important outcomes during tracheal intubation should not be distressed by these data. The teaching of tracheal intubation, as with most procedures, still involves at least a verbal checklist performed between an experienced instructor and inexperienced trainee. However, if the experienced instructor is the operator performing tracheal intubation, these data suggest neither the instructor nor the patient would significantly benefit from performing a preintubation checklist.

Published: July 2, 2020. doi:10.1001/jamanetworkopen.2020.9511

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2020 Janz DR. JAMA Network Open.

Corresponding Author: David R. Janz, MD, MSc, University Medical Center New Orleans, 2000 Canal St, New Orleans, LA 70112 (david.janz@lcmchealth.org).

Conflict of Interest Disclosures: None reported.