Acute Stroke: Current Evidence-based Recommendations for Prehospital Care

A comparative study on specialized services in pre-hospital emergencies in Iran and selected countries

The quality of emergency services is one of the indicators describing the health status of countries. Moreover, the specialization of services and targeted response to any accident or disease has been the priority of pre-hospital emergency operations in some leading countries. This study aimed to compare the special services provided in the emergency department of several selected countries. This was a comparative study that was done in Isfahan in 2022. Data were collected by reviewing the literature provided by libraries and emergency websites of selected countries. We selected countries based on the accessibility of information in two groups of developed countries and countries with the same income and population as Iran including Germany, France, The United States, Australia, Britain, Malaysia, and Turkey. Data were classified and compared based on staff, vehicles, and specialized services. Emergency staffs in most countries were of different skill and training levels. Ambulances varied in equipment types in various land, air, and sea forms and dimensions. Developed countries had more modern ambulances and equipment. France and Germany were operating more especially. Specialized teams are dispatched only in the United States and Germany. Existing studies have shown the adequacy and effectiveness of these teams in reducing complications and mortality and improving the prognosis of patients. The use of specialized teams appropriate to each emergency based on the specific and targeted response is effective in improving the prognosis of patients. The results of this study are suggested to beneficiaries to improve the quality of emergency care and reduce complications and potential causalities.

A systematic review and synthesis of global stroke guidelines on behalf of the World Stroke Organization

BACKGROUND

There are multiple stroke guidelines globally. To synthesize these and summarize what existing stroke guidelines recommend about the management of people with stroke, the World Stroke Organization (WSO) Guideline committee, under the auspices of the WSO, reviewed available guidelines.

AIMS

To systematically review the literature to identify stroke guidelines (excluding primary stroke prevention and subarachnoid hemorrhage) since 1 January 2011, evaluate quality (The international Appraisal of Guidelines, Research and Evaluation (AGREE II)), tabulate strong recommendations, and judge applicability according to stroke care available (minimal, essential, advanced).

SUMMARY OF REVIEW

Searches identified 15,400 titles; 911 texts were retrieved, 200 publications scrutinized by the three subgroups (acute, secondary prevention, rehabilitation), and recommendations extracted from most recent version of relevant guidelines. For acute treatment, there were more guidelines about ischemic stroke than intracerebral hemorrhage; recommendations addressed pre-hospital, emergency, and acute hospital care. Strong recommendations were made for reperfusion therapies for acute ischemic stroke. For secondary prevention, strong recommendations included establishing etiological diagnosis; management of hypertension, weight, diabetes, lipids, and lifestyle modification; and for ischemic stroke, management of atrial fibrillation, valvular heart disease, left ventricular and atrial thrombi, patent foramen ovale, atherosclerotic extracranial large vessel disease, intracranial atherosclerotic disease, and antithrombotics in non-cardioembolic stroke. For rehabilitation, there were strong recommendations for organized stroke unit care, multidisciplinary rehabilitation, task-specific training, fitness training, and specific interventions for post-stroke impairments. Most recommendations were from high-income countries, and most did not consider comorbidity, resource implications, and implementation. Patient and public involvement was limited.

CONCLUSION

The review identified a number of areas of stroke care where there was strong consensus. However, there was extensive repetition and redundancy in guideline recommendations. Future guideline groups should consider closer collaboration to improve efficiency, include more people with lived experience in the development process, consider comorbidity, and advise on implementation.

Emergency Medical Services Stroke Care Performance Variability in Michigan: Analysis of a Statewide Linked Stroke Registry

Background Emergency medical services (EMS) compliance with recommended prehospital care for patients with acute stroke is inconsistent; however, sources of variability in compliance are not well understood. The current analysis utilizes a linkage between a statewide stroke registry and EMS information system data to explore patient and EMS agency-level contributions to variability in prehospital care. Methods and Results This is a retrospective analysis of a cohort of confirmed stroke cases transported by EMS to hospitals participating in a statewide stroke registry. Using EMS information system data, the authors quantified EMS compliance with 6 performance measures derived from national guidelines for prehospital stroke care: prehospital stroke scale performance, glucose check, stroke recognition, on-scene time ≤15 minutes, time last known well documentation, and hospital prenotification. Multilevel multivariable logistic regression analysis was then used to examine associations between patient-level demographic and clinical characteristics and EMS compliance while accounting for and quantifying the variation attributable to agency of transport and recipient hospital. Over an 18-month period, EMS and stroke registry records were linked for 5707 EMS-transported stroke cases. Compliance ranged from 24% of cases for last known well documentation to 82% for documentation of a glucose check. The other measures were documented in approximately half of cases. Older age, higher National Institutes of Health Stroke Scale, and earlier presentation were associated with more compliant prehospital care. EMS agencies accounted for more than half of the variation in EMS prehospital stroke scale documentation and last known well documentation and 27% of variation in glucose check but <10% of stroke recognition and prenotification variability. Conclusions EMS stroke care remains highly variable across different performance measures and EMS agencies. EMS agency and electronic medical record type are important sources of variability in compliance with key prehospital performance metrics for stroke.

Human vs. Machine Learning Based Detection of Facial Weakness Using Video Analysis

Background

Current EMS stroke screening tools facilitate early detection and triage, but the tools' accuracy and reliability are limited and highly variable. An automated stroke screening tool could improve stroke outcomes by facilitating more accurate prehospital diagnosis and delivery. We hypothesize that a machine learning algorithm using video analysis can detect common signs of stroke. As a proof-of-concept study, we trained a computer algorithm to detect presence and laterality of facial weakness in publically available videos with comparable accuracy, sensitivity, and specificity to paramedics.

Methods and Results

We curated videos of people with unilateral facial weakness (n = 93) and with a normal smile (n = 96) from publicly available web-based sources. Three board certified vascular neurologists categorized the videos according to the presence or absence of weakness and laterality. Three paramedics independently analyzed each video with a mean accuracy, sensitivity and specificity of 92.6% [95% CI 90.1–94.7%], 87.8% [95% CI 83.9–91.7%] and 99.3% [95% CI 98.2–100%]. Using a 5-fold cross validation scheme, we trained a computer vision algorithm to analyze the same videos producing an accuracy, sensitivity and specificity of 88.9% [95% CI 83.5–93%], 90.3% [95% CI 82.4–95.5%] and 87.5 [95% CI 79.2–93.4%].

Conclusions

These preliminary results suggest that a machine learning algorithm using computer vision analysis can detect unilateral facial weakness in pre-recorded videos with an accuracy and sensitivity comparable to trained paramedics. Further research is warranted to pursue the concept of augmented facial weakness detection and external validation of this algorithm in independent data sets and prospective patient encounters.

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

OBJECTIVES

Emergency Medicine Service (EMS) providers play a pivotal role in early identification and initiation of treatment for stroke. The objective of this study is to characterize nationwide EMS practices for suspected stroke and assess for gender-based differences in compliance with American Stroke Association (ASA) guidelines.

MATERIALS AND METHODS

Using the 2019-2020 National Emergency Medical Services Information System (NEMSIS) Datasets, we identified encounters with an EMS designated primary impression of stroke. We characterized patient characteristics and EMS practices and assessed compliance with eight metrics for "guideline-concordant" care. Multivariable logistic regression modeled the association between gender and the primary outcome (guideline-concordant care), adjusted for age, EMS level of service, EMS geographical region, region type (i.e. urban or rural), and year.

RESULTS

Of 693,177 encounters with a primary impression of stroke, overall compliance with each performance metric ranged from 18% (providing supplemental oxygen when the pulse oximetry is less than 94%) to 76% (less than 90sec from incoming call to EMS dispatch). 2,382 (0.39%) encounters were fully guideline-concordant. Women were significantly less likely than men to receive guideline-concordant care (adjusted OR 0.82, 95% CI 0.75-0.89; 0.36% women, 0.43% men with guideline-concordant care).

CONCLUSIONS

A minority of patients received prehospital stroke care that was documented to be compliant with ASA guidelines. Women were less likely to receive fully guideline-compliant care compared to men, after controlling for confounders, although the difference was small and of uncertain climical importance. Further studies are needed to evaluate the underlying reasons for this disparity, its impact on patient outcomes, and to identify potential targeted interventions to improve prehospital stroke care.

Quality of stroke guidelines in low- and middle-income countries: a systematic review

OBJECTIVE

To identify gaps in national stroke guidelines that could be bridged to enhance the quality of stroke care services in low- and middle-income countries.

METHODS

We systematically searched medical databases and websites of medical societies and contacted international organizations. Country-specific guidelines on care and control of stroke in any language published from 2010 to 2020 were eligible for inclusion. We reviewed each included guideline for coverage of four key components of stroke services (surveillance, prevention, acute care and rehabilitation). We also assessed compliance with the eight Institute of Medicine standards for clinical practice guidelines, the ease of implementation of guidelines and plans for dissemination to target audiences.

FINDINGS

We reviewed 108 eligible guidelines from 47 countries, including four low-income, 24 middle-income and 19 high-income countries. Globally, fewer of the guidelines covered primary stroke prevention compared with other components of care, with none recommending surveillance. Guidelines on stroke in low- and middle-income countries fell short of the required standards for guideline development; breadth of target audience; coverage of the four components of stroke services; and adaptation to socioeconomic context. Fewer low- and middle-income country guidelines demonstrated transparency than those from high-income countries. Less than a quarter of guidelines encompassed detailed implementation plans and socioeconomic considerations.

CONCLUSION

Guidelines on stroke in low- and middle-income countries need to be developed in conjunction with a wider category of health-care providers and stakeholders, with a full spectrum of translatable, context-appropriate interventions.

Prehospital time of suspected stroke patients treated by emergency medical service: a nationwide study in Thailand

Background

This work was to study the prehospital time among suspected stroke patients who were transported by an emergency medical service (EMS) system using a national database.

Methods

National EMS database of suspected stroke patients who were treated by EMS system across 77 provinces of Thailand between January 1, 2015, and December 31, 2018, was retrospectively analyzed. Demographic data (i.e., regions, shifts, levels of ambulance, and distance to the scene) and prehospital time (i.e., dispatch, activation, response, scene, and transportation time) were extracted. Time parameters were also categorized according to the guidelines.

Results

Total 53,536 subjects were included in the analysis. Most of the subjects were transported during 06.00-18.00 (77.5%) and were 10 km from the ambulance parking (80.2%). Half of the subjects (50.1%) were served by advanced life support (ALS) ambulance. Median total time was 29 min (IQR 21, 39). There was a significant difference of median total time among ALS (30 min), basic (27 min), and first responder (28 min) ambulances, Holm P = 0.009. Although 91.7% and 88.3% of the subjects had dispatch time ≤ 1 min and activation time ≤ 2 min, only 48.3% had RT ≤ 8 min. However, 95% of the services were at the scene ≤ 15 min.

Conclusion

Prehospital time from EMS call to hospital was approximately 30 min which was mainly utilized for traveling from the ambulance parking to the scene and transporting patients from the scene to hospitals. Even though only 48% of the services had RT ≤ 8 min, 95% of them had the scene time ≤ 15 min.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12245-021-00361-w.

Potential accuracy of prehospital NIHSS-based triage for selection of candidates for acute endovascular stroke therapy

OBJECTIVE

Whether patients with acute stroke and large vessel occlusion (LVO) benefit from prehospital identification and diversion by emergency medical services (EMS) to an endovascular stroke therapy (EST)-capable center is controversial. We sought to estimate the accuracy of field-based identification of potential EST candidates in a hypothetical best-of-all-worlds situation.

METHODS

In Kaiser Permanente Northern California, all acute stroke patients arriving at its 21 stroke centers between 7:00 am and midnight from January 2016 to December 2019 were evaluated by teleneurologists on arrival. Initial National Institutes of Health Stroke Scale (NIHSS) score, presence of LVO, and referral for EST were obtained from standardized teleneurology notes. Factors associated with LVO were evaluated using generalized estimating equations accounting for clustering by facility.

RESULTS

Among 13,377 patients brought in by EMS with potential stroke, 7168 (53.6%) were not candidates for acute stroke interventions. Of the remaining 6089 cases, 2,573 (42.3%) had an NIHSS score >10, the cutoff with a higher association for LVO. Only 703 patients (27.3% with NIHSS score >10) were ultimately diagnosed with LVO and referred for EST. Across all NIHSS scores, only 884 (6.6%) suspected acute stroke patients had LVO and EST referral.

CONCLUSIONS

Even if field-based tools were as accurate as NIHSS scoring and predictions by stroke neurologists, only about 1 in 4 acute stroke patients diverted to EST-capable centers would benefit by receiving EST. Depending on geography and stroke center performance on door-to-needle time, many systems may be better served by focusing on expediting evaluation, treatment with intravenous thrombolysis, and transfer to EST-capable centers.

Video-Based Facial Weakness Analysis

OBJECTIVE

Facial weakness is a common sign of neurological diseases such as Bell's palsy and stroke. However, recognizing facial weakness still remains as a challenge, because it requires experience and neurological training.

METHODS

We propose a framework for facial weakness detection, which models the temporal dynamics of both shape and appearance-based features of each target frame through a bi-directional long short-term memory network (Bi-LSTM). The system is evaluated on a "in-the-wild"video dataset that is verified by three board-certified neurologists. In addition, three emergency medical services (EMS) personnel and three upper level residents rated the dataset. We compare the evaluation of the proposed algorithm with other comparison methods as well as the human raters.

RESULTS

Experimental evaluation demonstrates that: (1) the proposed algorithm achieves the accuracy, sensitivity, and specificity of 94.3%, 91.4%, and 95.7%, which outperforms other comparison methods and achieves the equal performance to paramedics; (2) the framework can provide visualizable and interpretable results that increases model transparency and interpretability; (3) a prototype is implemented as a proof-of-concept showcase to show the feasibility of an inexpensive solution for facial weakness detection.

CONCLUSION

The experiment results suggest that the proposed framework can identify facial weakness effectively.

SIGNIFICANCE

We provide a proof-of-concept study, showing that such technology could be used by non-neurologists to more readily identify facial weakness in the field, leading to increasing coverage and earlier treatment.

Pediatric respiratory distress: California out-of-hospital protocols and evidence-based recommendations

OBJECTIVES

Prehospital protocols vary across local emergency medical service (EMS) agencies in California. We sought to develop evidence-based recommendations for the out-of-hospital evaluation and treatment of pediatric respiratory distress, and we evaluated the protocols for pediatric respiratory distress used by the 33 California local EMS agencies.

METHODS

Evidence-based recommendations were developed through an extensive literature review of the current evidence regarding out-of-hospital treatment of pediatric patients with respiratory distress. The authors compared the pediatric respiratory distress protocols of each of the 33 California local EMS agencies with the evidence-based recommendations. Our focus was on the treatment of 3 main pediatric respiratory complaints by presentation: stridor (croup), wheezing < 24 months (bronchiolitis), and wheezing > 24 months (asthma).

RESULTS

Protocols across the 33 California local EMS agencies varied widely. Stridor (croup) had the highest protocol variability of the 3 presentations we evaluated, with no treatment having uniform use among all agencies. Only 3 (9.1%) of the local EMS agencies differentiated wheezing in children < 24 months of age, referencing this as possible bronchiolitis. All local EMS agencies included albuterol and epinephrine (intravenous/intramuscular) in their pediatric wheezing (asthma) treatment protocols. The least common treatments for wheezing (asthma) included nebulized epinephrine (3/33) and magnesium (2/33). No agencies included steroids in their treatment protocols (0/33).

CONCLUSION

Protocols for pediatric respiratory distress vary widely across the state of California, especially among those for stridor (croup) and wheezing in < 24 months (bronchiolitis). The evidence-based recommendations that we present for the prehospital treatment of these conditions may be useful for EMS medical directors tasked with creating and revising these protocols.

A Decision Support Method for Prehospital Emergency Care Based on Ranking the Importance of Physiological Variables

To the on-site nursing staff or field management in prehospital emergency care, it seems baffling to conduct more targeted checklist tests for a specific disease. To address this problem, we proposed a decision support method for prehospital emergency care based on ranking the importance of physiological variables. We used multiple logistic regression models to explore the effects of various physiological variables on diseases based on the area under the curve (AUC) value. We implemented the method on the intensive care database (i.e., the Medical Information Mart for Intensive Care (MIMIC-III) database) and explored the importance of 17 physiological variables for 24 diseases, both chronic and acute. We included 33,798 adult patients, using the full physiological dataset as experiment data. We ranked the importance of the physiological variables related to the diseases according to the experiments’ AUC value. We discussed which physiological variables should be considered more important in adult intensive care units (ICUs) for prehospital emergency care conditions. We also discussed the relationships among the diseases based on ranking the importance of physiological variables. We used large-scale ICU patient data to obtain a cohort of physiological variables related to specific diseases. Ranking a cohort of physiological variables is a cost-effective means of reducing morbidity and mortality under prehospital emergency care conditions.

Adult Patients with Respiratory Distress: Current Evidence-based Recommendations for Prehospital Care

INTRODUCTION

We developed evidence-based recommendations for prehospital evaluation and treatment of adult patients with respiratory distress. These recommendations are compared with current protocols used by the 33 local emergency medical services agencies (LEMSA) in California.

METHODS

We performed a review of the evidence in the prehospital treatment of adult patients with respiratory distress. The quality of evidence was rated and used to form guidelines. We then compared the respiratory distress protocols of each of the 33 LEMSAs for consistency with these recommendations.

RESULTS

PICO (population/problem, intervention, control group, outcome) questions investigated were treatment with oxygen, albuterol, ipratropium, steroids, nitroglycerin, furosemide, and non-invasive ventilation. Literature review revealed that oxygen titration to no more than 94-96% for most acutely ill medical patients and to 88-92% in patients with acute chronic obstructive pulmonary disease (COPD) exacerbation is associated with decreased mortality. In patients with bronchospastic disease, the data shows improved symptoms and peak flow rates after the administration of albuterol. There is limited data regarding prehospital use of ipratropium, and the benefit is less clear. The literature supports the use of systemic steroids in those with asthma and COPD to improve symptoms and decrease hospital admissions. There is weak evidence to support the use of nitrates in critically ill, hypertensive patients with acute pulmonary edema (APE) and moderate evidence that furosemide may be harmful if administered prehospital to patients with suspected APE. Non-invasive positive pressure ventilation (NIPPV) is shown in the literature to be safe and effective in the treatment of respiratory distress due to acute pulmonary edema, bronchospasm, and other conditions. It decreases both mortality and the need for intubation. Albuterol, nitroglycerin, and NIPPV were found in the protocols of every LEMSA. Ipratropium, furosemide, and oxygen titration were found in a proportion of the protocols, and steroids were not prescribed in any LEMSA protocol.

CONCLUSION

Prehospital treatment of adult patients with respiratory distress varies widely across California. We present evidence-based recommendations for the prehospital treatment of undifferentiated adult patients with respiratory distress that will assist with standardizing management and may be useful for EMS medical directors when creating and revising protocols.

Acute ischemic stroke: improving access to intravenous tissue plasminogen activator

INTRODUCTION

Since approval by the United States Food and Drug Administration in 1996, alteplase utilization rates for acute ischemic stroke have increased. Despite its efficacy for improving stroke outcomes, however, the majority of ischemic stroke patients still do not receive alteplase. To address this issue, different methods for improving access to alteplase have been tested with varying degrees of success.

AREAS COVERED

This article gives an overview of the recent approaches pursued to improve access to alteplase for acute ischemic stroke patients. Utilization of stroke systems of care, quality metrics, and quality-improvement initiatives to improve alteplase treatment rates are discussed. The implementation of Telestroke networks to improve access and timely evaluation by a stroke specialist are also reviewed. Lastly, this review discusses the use of neuroimaging techniques to identify alteplase candidates in stroke of unknown symptom onset or beyond the 4.5-h treatment window.

EXPERT COMMENTARY

Expanding access to alteplase therapy for acute ischemic stroke is a multi-faceted approach. Specific considerations based on region, population, and health-care resources should be considered for each strategy. Neuroimaging approaches to identify alteplase-eligible patients beyond the 4.5-h treatment window are a recent development in acute stroke care that holds promise for increasing alteplase treatment rates.

Validity of the Pediatric Early Warning Score and the Bedside Pediatric Early Warning Score in Classifying Patients Who Require the Resources of a Higher Level Pediatric Hospital

Introduction: The pediatric early warning score (PEWS) and the bedside pediatric early warning score (BPEWS) are validated tools that help determine the need for critical care in children with acute medical conditions. These tools could be used by EMS and have not been evaluated outside of the hospital. This study retrospectively tested the validity of these tools in the prehospital setting to identify children who needed a hospital with higher level pediatric resources. Methods: This was a multi-center retrospective validation of screening tools using prehospital and in-hospital data obtained from 3 EMS agencies. EMS patient records from April 1, 2013 to April 30, 2015 were used to identify subjects for this analysis. Pediatric patients were retrospectively classified using the PEWS based on the clinical information documented in the EMS medical record. Those with PEWS scores greater than 4 were matched to a subject with scores less than 4 based on age, gender, and paramedic primary impression. Hospital medical record review was then used to determine whether the patient required a hospital with higher level pediatric resources. These classifications were used to calculate sensitivity, specificity, and resultant 95% confidence intervals. The analysis was repeated for included subjects who had sufficient data to calculate BPEWS. Results: There were 386 patients enrolled. A PEWS ≥ 4 demonstrated a sensitivity of 62.8 (95% CI 53.6-71.4) and a specificity of 55.9 (95% CI 49.6-61.9) in identifying a patient who required a hospital with higher level pediatric resources. There were 44 pairs of patients that had sufficient EMS data documented to calculate a BPEWS. A BPEWS ≥ 7 demonstrated a sensitivity of 46.4 (95% CI 27.5-66.1) and a specificity of 76.7 (95% CI 64.0-86.6) to correctly classify a patient who required a hospital with higher level pediatric resources. Conclusion: In the prehospital setting neither PEWS nor BPEWS exhibited sufficient sensitivity for clinical use to accurately identify children who need a hospital with higher level pediatric resources. Further research should be conducted to identify variables that are captured by prehospital care providers and are associated with children who need a hospital with higher level pediatric resources.

Increased Access to and Use of Endovascular Therapy Following Implementation of a 2-Tiered Regional Stroke System

Background and Purpose—

We quantified population access to endovascular-capable centers, timing, and rates of thrombectomy in Los Angeles County before and after implementing 2-tiered routing in a regional stroke system of care.

Methods—

In 2018, the Los Angeles County Emergency Medical Services Agency implemented transport of patients with suspected large vessel occlusions identified by Los Angeles Motor Scale ≥4 directly to designated endovascular-capable centers. We calculated population access to a designated endovascular-capable center within 30 minutes comparing 2016, before 2-tiered system planning began, to 2018 after implementation. We analyzed data from stroke centers in the region from 1 year before and after implementation to delineate changes in rates and speed of administration of tPA (tissue-type plasminogen activator) and thrombectomy and frequency of interfacility transfer.

Results—

With implementation of the 2-tier system, certified endovascular-capable hospitals increased from 4 to 19 centers, and within 30-minute access to endovascular care for the public in Los Angeles County, from 40% in 2016 to 93% in 2018. Comparing Emergency Medical Services–transported stroke patients in the first post-implementation year (N=3303) with those transported in the last pre-implementation year (N=3008), age, sex, and presenting deficit severity were similar. The frequency of thrombolytic therapy increased from 23.8% to 26.9% (odds ratio, 1.2 [95% CI, 1.05–1.3]; P =0.006), and median first medical contact by paramedic-to-needle time decreased by 3 minutes ([95% CI, 0–5] P =0.03). The frequency of thrombectomy increased from 6.8% to 15.1% (odds ratio, 2.4 [95% CI, 2.0–2.9]; P <0.0001), although first medical contact-to-puncture time did not change significantly, median decrease of 8 minutes ([95% CI, −4 to 20] P =0.2). The frequency of interfacility transfers declined from 3.2% to 1.0% (odds ratio, 0.3 [95% CI, 0.2–0.5]; P <0.0001).

Conclusions—

After implementation of 2-tiered stroke routing in the most populous US county, thrombectomy access increased to 93% of the population, and the frequency of thrombectomy more than doubled, whereas interfacility transfers declined.

Prehospital supplemental oxygen for acute stroke - A retrospective analysis

OBJECTIVE

Brief early administration of supplemental oxygen (sO₂) to create hyperoxia may increase oxygenation to penumbral tissue and improve stroke outcomes. Hyperoxia may also result in respiratory compromise and vasoconstriction leading to worse outcomes. This study examines the effects of prehospital sO₂ in stroke.

METHODS

This is a retrospective analysis of adult acute stroke patients (aged ≥18 years) presenting via EMS to an academic Comprehensive Stroke Center between January 1, 2013 and December 31, 2017. Demographic and clinical characteristics obtained from Get with the Guidelines-Stroke registry and subjects' medical records were compared across three groups based on prehospital oxygen saturation and sO₂ administration. Chi-square, ANOVA, and multivariate logistic regression were used to determine if sO₂ status was associated with neurological outcomes or respiratory complications.

RESULTS

1352 eligible patients were identified. 62.7% (n = 848) did not receive sO₂ ("controls"), 10.7% (n = 144) received sO₂ due to hypoxia ("hypoxia"), and 26.6% (n = 360) received sO₂ despite normoxia ("hyperoxia"). The groups represented a continuum from more severe deficits (hypoxia) to less severe deficits (controls): mean prehospital GCS (hypoxia -12, hyperoxia - 2, controls - 14 p ≤ 0.001), mean initial NIHSS (hypoxia - 15, hyperoxia - 13, controls - 8 p < 0.001). After controlling for potential confounders, all groups had similar rates of respiratory complications and favorable neurological outcomes.

CONCLUSIONS

Hyperoxic subjects had no significant increase in respiratory complications, nor did they differ in neurologic outcomes at discharge when controlling for confounders. While limited by the retrospective nature, this suggests brief, early sO₂ for stroke may be safe to evaluate prospectively.

The role of the Cincinnati Prehospital Stroke Scale in the emergency department: evidence from a systematic review and meta-analysis

Introduction

Stroke is one of the leading causes of morbidity, disability, and mortality in high-income countries. Early prehospital stroke recognition plays a fundamental role, because most clinical decisions should be made within the first hours after onset of symptoms. The Cincinnati Prehospital Stroke Scale (CPSS) is a validated screening tool whose utilization is suggested during triage. The aim of this study is to review the role of the CPSS by assessing its sensitivity and specificity in prehospital and hospital settings.

Methods

A systematic review and a meta-analysis of the literature reporting the CPSS sensitivity and specificity among patients suspected of stroke were undertaken. Electronic databases were searched up to December 2018, and the quality assessment was carried out by using the Revised Quality Assessment of Diagnostic Accuracy Studies −2  (QUADAS-2).

Results

Eleven studies were included in the meta-analysis. Results showed an overall sensitivity of 82.46% (95% confidence interval [CI] 74.83–88.09%) and specificity of 56.95% (95% CI 41.78–70.92). No significant differences were found in terms of sensitivity when CPSS was performed by physicians (80.11%, 95% CI 66.14–89.25%) or non-physicians (81.11%, 95% CI 69.78–88.87%). However, administration by physicians resulted in higher specificity (73.57%, 95% CI 65.78–80.12%) when compared to administration by non-physicians (50.07%, 95% CI 31.54–68.58%). Prospective studies showed higher specificity 71.61% (95% CI 61.12–80.18%) and sensitivity 86.82% (95% CI 74.72–93.63) when compared to retrospective studies which showed specificity of 33.37% (95% CI 22.79–45.94%) and sensitivity of 78.52% (95% CI 75.08–81.60).

Conclusions

The CPSS is a standardized and easy-to-use stroke screening tool whose implementation in emergency systems protocols, along with proper and consistent coordination with local, regional, and state agencies, medical authorities and local experts are suggested.

A Retrospective Study Investigating: Factors associated with mode of arrival and emergency department management for patients with acute stroke

BACKGROUND

Presentation by ambulance to the emergency department is critical for stroke patients to receive time dependent treatments. However, little is known of the factors that influence presentation by ambulance.

METHODS

Retrospective analysis of all patients with an emergency department medical diagnosis of stroke who presented to one of three Victorian emergency departments over a three-year period (2011-2013). A multivariable model was used to investigate demographic characteristics (including triage assessment category, triage identified as stroke, time to CT, and time to diagnosis within the emergency department) as predictors of arrival by ambulance.

RESULTS

3548 stroke patients were identified; mean age was 70 years, 53% were males, and 92% had an ischemic stroke. Arrival by ambulance occurred in 71% (n=2509) with arrival by private transport accounting for 29% (n=1039) of patients. Factors significantly associated with arrival by ambulance were older age (p=<0.001), being born in Australia (p=<0.001), and speaking English in the home (p=0.003). Arrival by ambulance was independently associated with rapid stroke care in the emergency department, arrival within 2h from symptom onset, attending an advanced stroke service (access to thrombolysis), triaged for stroke, medical assessment within 25min and referral for CT within 45min.

CONCLUSION

In this Australian multicenter study, it was identified that patients who arrived by ambulance received faster acute stroke care within the emergency department. Public health education which targets patients who are younger and from a non-English speaking background is needed as these demographics were not associated with timely arrival by ambulance to the emergency department.

Altered Mental Status: Current Evidence-based Recommendations for Prehospital Care

Introduction

In the United States emergency medical services (EMS) protocols vary widely across jurisdictions. We sought to develop evidence-based recommendations for the prehospital evaluation and treatment of a patient with an acute change in mental status and to compare these recommendations against the current protocols used by the 33 EMS agencies in the State of California.

Methods

We performed a literature review of the current evidence in the prehospital treatment of a patient with altered mental status (AMS) and augmented this review with guidelines from various national and international societies to create our evidence-based recommendations. We then compared the AMS protocols of each of the 33 EMS agencies for consistency with these recommendations. The specific protocol components that we analyzed were patient assessment, point-of-care tests, supplemental oxygen, use of standardized scoring, evaluating for causes of AMS, blood glucose evaluation, toxicological treatment, and pediatric evaluation and management.

Results

Protocols across 33 EMS agencies in California varied widely. All protocols call for a blood glucose check, 21 (64%) suggest treating adults at <60mg/dL, and half allow for the use of dextrose 10%. All the protocols recommend naloxone for signs of opioid overdose, but only 13 (39%) give specific parameters. Half the agencies (52%) recommend considering other toxicological causes of AMS, often by using the mnemonic AEIOU TIPS. Eight (24%) recommend a 12-lead electrocardiogram; others simply suggest cardiac monitoring. Fourteen (42%) advise supplemental oxygen as needed; only seven (21%) give specific parameters. In terms of considering various etiologies of AMS, 25 (76%) give instructions to consider trauma, 20 (61%) to consider stroke, and 18 (55%) to consider seizure. Twenty-three (70%) of the agencies have separate pediatric AMS protocols; others include pediatric considerations within the adult protocol.

Conclusion

Protocols for patients with AMS vary widely across the State of California. The evidence-based recommendations that we present for the prehospital diagnosis and treatment of this condition may be useful for EMS medical directors tasked with creating and revising these protocols.

Variations in Cardiac Arrest Regionalization in California

Introduction

The development of cardiac arrest centers and regionalization of systems of care may improve survival of patients with out-of-hospital cardiac arrest (OHCA). This survey of the local EMS agencies (LEMSA) in California was intended to determine current practices regarding the treatment and routing of OHCA patients and the extent to which EMS systems have regionalized OHCA care across California.

Methods

We surveyed all of the 33 LEMSA in California regarding the treatment and routing of OHCA patients according to the current recommendations for OHCA management.

Results

Two counties, representing 29% of the California population, have formally regionalized cardiac arrest care. Twenty of the remaining LEMSA have specific regionalization protocols to direct all OHCA patients with return of spontaneous circulation to designated percutaneous coronary intervention (PCI)-capable hospitals, representing another 36% of the population. There is large variation in LEMSA ability to influence inhospital care. Only 14 agencies (36%), representing 44% of the population, have access to hospital outcome data, including survival to hospital discharge and cerebral performance category scores.

Conclusion

Regionalized care of OHCA is established in two of 33 California LEMSA, providing access to approximately one-third of California residents. Many other LEMSA direct OHCA patients to PCI-capable hospitals for primary PCI and targeted temperature management, but there is limited regional coordination and system quality improvement. Only one-third of LEMSA have access to hospital data for patient outcomes.

Is management of hyperglycaemia in acute phase stroke still a dilemma?

INTRODUCTION

Close monitoring of blood glucose levels during the immediate post-acute stroke phase is of great clinical value, as there is evidence that the risk of neurological deterioration is associated with both hyper- and hypoglycaemia. The aim of this review paper is to summarise the evidence on post-stroke blood glucose management and its impact on clinical outcomes, during the early post-acute stage.

FINDINGS

Post-stroke hyperglycaemia has been associated with increased cerebral oedema, haemorrhagic transformation, lower likelihood of recanalisation and deteriorating neurological state. Thus, hyperglycaemia during an acute stroke may result in poorer clinical outcomes, infarct progression, poor functional recovery and increased mortality rates. Although hypoglycaemia may also lead to poorer outcomes via further brain injury, it can be readily reversed by glucose administration. In most patients, the goal of regular treatment is euglycaemia and for acute-stroke patients, a reasonable approach is to target control of glucose level at 100-150 mg/dL.

CONCLUSION

Both hypoglycaemia and hyperglycaemia may lead to further brain injury and clinical deterioration; that is the reason these conditions should be avoided after stroke. Yet, when correcting hyperglycaemia, great care should be taken not to switch the patient into hypoglycaemia, and subsequently aggressive insulin administration treatment should be avoided. Early identification and prompt management of hyperglycaemia, especially in acute ischaemic stroke, is recommended. Although the appropriate level of blood glucose during acute stroke is still debated, a reasonable approach is to keep the patient in a mildly hyperglycaemic state, rather than risking hypoglycaemia, using continuous glucose monitoring.

Heads Up! A Novel Provocative Maneuver to Guide Acute Ischemic Stroke Management

BACKGROUND

A common dilemma in acute ischemic stroke management is whether to pursue recanalization therapy in patients with large vessel occlusions but minimal neurologic deficits. We describe and report preliminary experience with a provocative maneuver, i.e. 90-degree elevation of the head of bed for 30 min, which stresses collaterals and facilitates decision-making.

METHODS

A prospective cohort study of <7.5 h of acute anterior circulation territory ischemia patients with minimal deficits despite middle cerebral artery (MCA) or internal carotid artery (ICA) occlusive disease.

RESULTS

Five patients met the study entry criteria. Their mean age was 78.4 years (range 65-93). All presented with substantial deficits (median NIHSS score 11, range 5-22), but improved while in supine position during initial imaging to normal or near-normal (NIHSS score 0-2). MRA showed persistent M1 MCA occlusions in 4, critical ICA stenosis or occlusion in 1, and substantial perfusion-diffusion mismatch in all. To evaluate the potential for eventual collateral failure, patients were placed in a head of bed upright posture. Mean arterial pressure and heart rate were unchanged. Two showed no neurologic worsening and were treated with supportive care with excellent final outcome. Three showed worsening, including recurrent hemiparesis and aphasia at the 6th, recurrent aphasia at the 23rd, and recurrent hemineglect at the 15th upright minute. These 3 underwent endovascular recanalization therapies with successful reperfusion and excellent final outcome.

CONCLUSION

The 'Heads Up' test may be a useful, simple maneuver to assess the risk of collateral failure and guide the decision to pursue recanalization therapy in acute cerebral ischemia patients with minimal deficits despite persisting large cerebral artery occlusion.