Out-of-Hospital Intubation Trends Through the Coronavirus Disease 2019 Pandemic

"Dead or Alive?" Assessment of the Binary End-of-Event Outcome Indicator for the NEMSIS Public Research Dataset

OBJECTIVES

The National Emergency Medical Services Information System (NEMSIS) provides a robust set of data to evaluate prehospital care. However, a major limitation is that the vast majority of the records lack a definitive outcome. This study aimed to evaluate the performance of a recently proposed method ("MLB" method) to impute missing end-of-EMS-event outcomes ("dead" or "alive") for patient care reports in the NEMSIS public research dataset.

METHODS

This study reproduced the recently published method for patient outcome imputation in the NEMSIS database and replicated the results for years 2017 through 2022 (n = 686,075). We performed statistical analyses leveraging an array of established performance metrics for binary classification from the machine learning literature. Evaluation metrics included overall accuracy, true positive rate, true negative rate, balanced accuracy, precision, F1 score, Cohen's Kappa coefficient, Matthews' coefficient, Hamming loss, the Jaccard similarity score, and the receiver operating characteristic/area under the curve.

RESULTS

Extended metrics show consistently good imputation performance from year-to-year but reveal weakness in accurately indicating the minority class: e.g., after adjustments for conflicting labels, "dead" prediction accuracy is 77.7% for 2018 and 61.8% over the six-year NEMSIS sub-sample, even though overall accuracy is 98.8%. Slight over-fitting is also present.

CONCLUSIONS

This study found that the recently published MLB method produced reasonably good "dead" or "alive" indicators. We recommend reporting of True Positive Rate ("dead" prediction accuracy) and True Negative Rate ("alive" prediction accuracy) when applying the imputation method for analyses of NEMSIS data. More attention by EMS clinicians to complete documentation of target NEMSIS elements can further improve the method's performance.

Longitudinal Changes in Emergency Medical Services Advanced Airway Management

Importance

Identifying longitudinal changes in advanced airway management by emergency medical services (EMS) is crucial for understanding practice patterns and optimizing care.

Objective

To examine the longitudinal trends in endotracheal intubation (ETI) and supraglottic airway (SGA) utilization in a national EMS cohort.

Design, Setting, and Participants

This retrospective cross-sectional study analyzed 2011 to 2022 data from the ESO Data Collaborative, a national database of US prehospital electronic health records. The study included all 911 EMS events in which advanced airway management was attempted. Data were analyzed from November 2022 to January 2024.

Exposures

Advanced airway management attempts, including ETI, SGA, and surgical airways.

Main Outcomes and Measures

The annual percentage of ETI and SGA attempts, stratified by underlying condition (cardiac arrest, nonarrest medical, nonarrest trauma, pediatrics).

Results

Among 47.5 million EMS activations, 444 041 (mean [SD] age, 60.6 [19.8] years; 273 296 [61.5%] men) involved advanced airway management, including 305 584 (68.8%) that used ETI and 200 437 (45.1%) that used SGA. The overall incidence was 9.3 per 1000 EMS events. In the cardiac arrest cohort from 2011 to 2022, EMS events with ETI attempts decreased from 2470 of 2831 (87.3%) to 40 083 of 72 793 (55.1%) and those with SGA attempts increased from 711 of 2831 (25.1%) to 44 386 of 72 793 (61.0%). In the pediatric subset, there were similarly large decreases in ETI attempts, from 117 of 182 EMS events (97.3%) to 1573 of 2307 EMS events (68.2%), and increases in SGA attempts, from 11 of 182 EMS events (6.6%) to 1058 of 2307 EMS events (45.9%). In the nonarrest medical and nonarrest trauma cohorts, ETI attempts decreased and SGA attempts increased but to a much lower extent.

Conclusions and Relevance

In this national cross-sectional study of EMS care episodes, there were marked shifts in advanced airway management practices, with the increased use of SGA and decreased use of ETI. These observations highlight current trends in EMS airway management practices.

Association Between Emergency Medical Service Agency Intubation Rate and Intubation Success

STUDY OBJECTIVE

Airway management is a crucial part of out-of-hospital care. It is not known if the rate of overall agency intubation attempts is associated with intubation success. We sought to evaluate the association between agency intubation attempt rate and intubation success using a national out-of-hospital database.

METHODS

We conducted a retrospective secondary analysis of the ESO Data Collaborative from 2018 to 2019, and included all adult cases with an endotracheal intubation attempt. We calculated the number of intubations attempted per 100 responses, advanced life support responses, and transports for each agency. We excluded cases originating at health care facilities and outliers. We used multivariable logistic regression to evaluate the association between agency intubation attempt rate and 1) intubation success and 2) first-pass success. We adjusted for confounders.

RESULTS

We included 1,005 agencies attempting 58,509 intubations. Overall, the intubation success rate was 78.8%, and the first-pass success rate was 68.5%. Per agency, the median rate of intubation attempts per 100 emergency medical service responses was 0.8 (interquartile range 0.6 to 1.1). Rates of intubation attempts per 100 responses (adjusted odds ratio [aOR] 1.7; 95% confidence interval [CI] 1.6 to 1.8), advanced life support responses (aOR 1.18; 95% CI 1.16 to 1.20), and transports (aOR 1.21; 95% CI 1.18 to 1.22) were all associated with intubation success. These relationships were similar for first-pass success but with smaller effect sizes.

CONCLUSION

Higher agency rates of intubation attempts were associated with increased rates of intubation success and first-pass success.