Analysis of Stroke Care Among 2019-2020 National Emergency Medical Services Information System Encounters

Evaluating the feasibility of prehospital point-of-care EEG: The prehospital implementation of rapid EEG (PHIRE) study

Background

Point-of-care electroencephalography (EEG) devices can be rapidly applied and do not require specialized technologists, creating new opportunities to use EEG during prehospital care. We evaluated the feasibility of point-of-care EEG during ambulance transport for 911 calls.

Methods

This mixed-methods study was conducted between May 28, 2022 and October 28, 2023. Emergency Medical Services (EMS) clinicians identified eligible individuals, provided emergent treatment, applied EEG, and obtained an EEG recording during ambulance transport. Eligible patients were aged 6 years or older and evaluated for seizure, stroke, or altered mental status. EMS clinicians completed a survey and a brief phone interview following every enrollment. Two epileptologists reviewed EEG recordings for interpretability and artifact.

Results

There were 34 prehospital encounters in which EEG was applied. Patients had a mean age of 69 years, and 15 (44%) were female. EEG recordings had a median duration of 10 min 30 s. It took EMS clinicians an average of 2.5 min to apply the device and begin EEG recording. There were 14 (47%) recordings where clinicians achieved a high-quality connection for all 10 electrodes and 32 (94%) recordings that were sufficient in quality to interpret. There were 24 (71%) recordings with six or more channels free of artifact for 5 min or more. All clinicians agreed or strongly agreed that the device was easy to use.

Conclusion

Among real-world prehospital encounters for patients with neurologic symptoms, point-of-care EEG was rapidly applied and yielded EEG recordings that could be used for clinical interpretation, demonstrating the feasibility of point-of-care EEG in future prehospital care.

Emergency Medical Services Compliance With Prehospital Stroke Quality Metrics Is Associated With Faster Stroke Evaluation and Treatment

BACKGROUND

Emergency medical services (EMS) is an important link in the stroke chain of recovery. Various prehospital quality metrics have been proposed for prehospital stroke care, but their individual impact is uncertain. We sought to measure associations between EMS quality metrics and downstream stroke care.

METHODS

This is a retrospective analysis of a cohort of EMS-transported stroke patients assembled through a linkage between Michigan's EMS and stroke registries. We used multivariable regression to quantify the independent associations between EMS quality metric compliance (dispatch within 90 seconds of 911 call, prehospital stroke screen documentation [Prehospital stroke scale], glucose check, last known well time, maintenance of scene times ≤15 minutes, hospital prenotification, and intravenous line placement) and shorter door-to-CT times (door-to-CT ≤25), accounting for EMS recognition, age, sex, race, stroke subtype, severity, and duration of symptoms. We then developed a simple EMS quality score based on metrics associated with early CT and examined its associations with hospital stroke evaluation times, treatment, and patient outcomes.

RESULTS

Five thousand seven hundred seven EMS-transported stroke cases were linked to prehospital records from January 2018 through June 2019. In multivariable analysis, prehospital stroke scale documentation (adjusted odds ratio, 1.4 [1.2-1.6]), glucose check (1.3 [1.1-1.6]), on-scene time ≤15 minutes (1.6 [1.4-1.9]), hospital prenotification ([2.0 [1.4-2.9]), and intravenous line placement (1.8 [1.5-2.1]) were independently associated with a door-to-CT ≤25 minutes. A 5-point quality score (1 point for each element) was therefore developed. In multivariable analysis, a 1-point higher EMS quality score was associated with a shorter time from EMS contact to CT (-9.2 [-10.6 to -7.8] minutes; P<0.001) and thrombolysis (-4.3 [-6.4 to -2.2] minutes; P<0.001), and higher odds of discharge to home (adjusted odds ratio, 1.1 [1.0-1.2]; P=0.002).

CONCLUSIONS

Five EMS actions recommended by national guidelines were associated with rapid CT imaging. A simple quality score derived from these measures was also associated with faster stroke evaluation, greater odds of reperfusion treatment, and discharge to home.

Sex differences in acute ischemic stroke presentation are a matter of infarct location

INTRODUCTION

Recognition of stroke by Emergency Medical Services (EMS) is critical to initiate rapid emergency department treatment. Most prehospital stroke screening tools rely heavily on presentation with the classic symptoms of facial droop, speech changes, unilateral weakness. However, women may be less likely to present with classic symptoms and may also have different distributions of stroke by anatomical location. This study seeks to determine the association between biological sex, presentation with classic symptoms, and the location of the infarcted tissue.

METHODS

This is a retrospective cohort study. Data from electronic health records were extracted for patients with acute ischemic stroke who presented via EMS to a single Comprehensive Stroke Center between January 1, 2018 and December 31, 2020. We used descriptive statistics characterize the cohort. Multivariable logistic regression identified factors associated with classic symptom presentation (facial droop, speech changes, and/or unilateral weakness). Biological sex, location of the infarct, stroke etiology, age and the interaction between sex and infarct location were assessed as covariates.

RESULTS

There were 364 (58.6%) males and 257 (41.1%) females with an acute ischemic stroke included in this study. EMS documented one or more classic symptoms in 125 (72.3%) males and 161 (67.9%) females. There were no baseline differences in infarct location or presentation with classic symptoms as documented by EMS comparing males and females. Multivariate logistic regression found no association between biological sex and presentation with classic symptoms (Odds Ratio 1.08; 95% CI 0.58 to 1.55) after controlling for age, stroke location, etiology of stroke or the interaction between sex and infarct location. Presence of an anterior circulation infarct compared to posterior circulation infarct was positively associated with a classic presentation to EMS (Odds Ratio 3.41; 95% CI 2.15 to 5.41).

CONCLUSIONS

This study found no difference in the frequency of patient presentation with classic stroke symptoms based on biological sex alone, nor a significant different in distribution of infarcts between males and females. Infarct location (i.e., involving the anterior circulation) was associated with a classic presentation. This suggests that the likelihood of presenting with classic stroke symptoms is not influenced by sex, but rather the location of the infarct.

Prehospital Stroke Care Part 1: Emergency Medical Services and the Stroke Systems of Care

Acute stroke care begins before hospital arrival, and several prehospital factors are critical in influencing overall patient care and poststroke outcomes. This topical review provides an overview of the state of the science on prehospital components of stroke systems of care and how emergency medical services systems may interact in the system to support acute stroke care. Topics include layperson recognition of stroke, prehospital transport strategies, networked stroke care, systems for data integration and real-time feedback, and inequities that exist within and among systems.