Gender Differences in Defibrillator Practices in Out-of-Hospital Cardiac Arrest.

OBJECTIVES: Disparities remain in survival after out-of-hospital cardiac arrest (OHCA) for women compared to men. Our objective was to evaluate differences in automated external defibrillator (AED) use before Emergency Medical Services (EMS) arrival and time from arrival to initial EMS defibrillation by EMS-assessed gender (women or men). METHODS: This was a secondary analysis of adult non-traumatic, EMS-treated OHCA cases in the Portland Cardiac Arrest Epidemiologic Registry from 2018 to 2021. Emergency Medical Services-witnessed cardiac arrests were excluded and the primary outcomes were pre-EMS AED application and the time from EMS arrival to first defibrillation among patients in a shockable rhythm at first rhythm assessment without pre-EMS AED application. We examined pre-EMS AED application rates overall and separately for law enforcement, in cases where they were on-scene before EMS without a lay bystander AED applied, and lay responders, in cases where law enforcement had not applied an AED. We used multivariable logistic and linear regressions to adjust for potential confounders, including age, arrest location, witness status, bystander CPR, year, and time from dispatch to EMS arrival. We accounted for clustering by county of arrest using a mixed-effects approach. RESULTS: Of the 3,135 adult, EMS-treated non-traumatic OHCAs that were not witnessed by EMS, 3,049 had all variables for analysis, of which 1,011 (33.2%) were women. The adjusted odds (adjusted odds ratio [95% CI]) for any pre-EMS placement of an AED was significantly higher for men compared to women (1.40 [1.05-1.86]). These odds favoring men remained when examining law enforcement AED application (1.89 [1.16-3.07]), but not lay bystander AED application (1.19 [0.83-1.71]). Among patients still in arrest on EMS arrival, with a shockable initial EMS rhythm, and without pre-EMS AED application, the time from EMS arrival on-scene to initial defibrillation was significantly longer for women compared to men (+0.81 min [0.22-1.41 min]). CONCLUSIONS: Women with OHCA received lower rates of pre-EMS AED application and delays in initial EMS defibrillation compared to men.

Utilization and Effect of Direct Medical Oversight during Out-of-Hospital Cardiac Arrest.

STUDY OBJECTIVE: Direct medical oversight (DMO), where emergency medical services (EMS) clinicians contact a physician for real-time medical direction, is used by many EMS systems across the United States. Our objective was to characterize the recommendations made by DMO during out-of-hospital cardiac arrests (OHCA) and to determine their effect on EMS transport decisions and patient outcomes. METHODS: This is a secondary analysis of DMO call recordings from OHCA cases in the Portland, Oregon metropolitan area from January 1, 2018 to February 28, 2021. Data extracted from the audio recordings were linked to OHCA cases in the Portland Cardiac Arrest Epidemiologic Registry (PDX Epistry). The primary outcomes are recommendations made by DMO: transport, continued field resuscitation, or termination of resuscitation (TOR). Secondary outcomes include EMS transport decisions, survival to hospital admission, and survival to hospital discharge. We used descriptive statistics, unpaired t-tests, and chi-square tests as appropriate for data analysis. RESULTS: There were 239 OHCA cases for which DMO was contacted by EMS. The median time from EMS arrival to DMO contact was 25.6 min, and EMS requested TOR for 72.0% of patients. Compared to patients where EMS requested further treatment advice, patients for whom EMS requested TOR had poor prognostic signs including older age, asystole as an initial rhythm, and lower rates of transient return of spontaneous circulation prior to DMO call compared with cases where EMS did not request TOR. DMO recommended transport, continued field resuscitation, or TOR in 21.8%, 18.0%, and 60.2% of patients, respectively. Of the 239 patients, 59 (24.7%) were ultimately transported by EMS to the hospital, 14 (5.9%) survived to admission, and only 1 patient (0.4%) survived to hospital discharge and had an acceptable neurologic outcome (Cerebral Performance Category score of 2). CONCLUSIONS: Patients for whom EMS contacts DMO for further treatment advice or requesting field TOR after prolonged OHCA resuscitation have poor outcomes, even when DMO recommends transport or further resuscitation, and may represent opportunities to reduce unnecessary DMO contact or patient transports. More research is needed to determine which OHCA patients benefit from DMO contact.

Outcomes with Tibial and Humeral Intraosseous Access Compared to Peripheral Intravenous Access in Out-of-Hospital Cardiac Arrest.

BACKGROUND: The optimal initial vascular access strategy for out-of-hospital cardiac arrest (OHCA) remains unknown. Our objective was to evaluate the association between peripheral intravenous (PIV), tibial intraosseous (TIO), or humeral intraosseous (HIO) as first vascular attempt strategies and outcomes for patients suffering OHCA. METHOD: This was a secondary analysis of the Portland Cardiac Arrest Epidemiologic Registry, which included adult patients (≥18 years-old) with EMS-treated, non-traumatic OHCA from 2018-2021. The primary independent variable in our analysis was the initial vascular access strategy, defined as PIV, TIO, or HIO based on the first access attempt. The primary outcome for this study was the return of spontaneous circulation (ROSC) at emergency department (ED) arrival (a palpable pulse on arrival to the hospital). Secondary outcomes included survival to: admission, discharge, and discharge with a favorable outcome (Cerebral Perfusion Category score of ≤2). We conducted multivariable logistic regressions, adjusting for confounding variables and for clustering using a mixed-effects approach, with prespecified subgroup analyses by initial rhythm. RESULTS: We included 2,993 patients with initial vascular access strategies of PIV (822 [27.5%]), TIO (1,171 [39.1%]), and HIO (1,000 [33.4%]). Multivariable analysis showed lower odds of ROSC at ED arrival (adjusted odds ratio [95% CI]) with TIO (0.79 [0.64-0.98]) or HIO (0.75 [0.60-0.93]) compared to a PIV-first strategy. These associations remained in stratified analyses for those with shockable initial rhythms (0.60 [0.41-0.88] and 0.53 [0.36-0.79]) but not in patients with asystole or pulseless electrical activity for TIO and HIO compared to PIV, respectively. There were no statistically significant differences in adjusted odds for survival to admission, discharge, or discharge with a favorable outcome for TIO or HIO compared to the PIV-first group in the overall analysis. Patients with shockable initial rhythms had lower adjusted odds of survival to discharge (0.63 [0.41-0.96] and 0.64 [0.41-0.99]) and to discharge with a favorable outcome (0.60 [0.39-0.93] and 0.64 [0.40-1.00]) for TIO and HIO compared to PIV, respectively. CONCLUSIONS: TIO or HIO as first access strategies in OHCA were associated with lower odds of ROSC at ED arrival compared to PIV.

Prehospital Drug Assisted Airway Management: An NAEMSP Position Statement and Resource Document.

Airway management is a critical intervention for patients with airway compromise, respiratory failure, and cardiac arrest. Many EMS agencies use drug-assisted airway management (DAAM) - the administration of sedatives alone or in combination with neuromuscular blockers - to facilitate advanced airway placement in patients with airway compromise or impending respiratory failure who also have altered mental status, agitation, or intact protective airway reflexes. While DAAM provides several benefits including improving laryngoscopy and making insertion of endotracheal tubes and supraglottic airways easier, DAAM also carries important risks. NAEMSP recommends:DAAM is an appropriate tool for EMS clinicians in systems with clear guidelines, sufficient training, and close EMS physician oversight. DAAM should not be used in settings without adequate resources.EMS physicians should develop clinical guidelines informed by evidence and oversee the training and credentialing for safe and effective DAAM.DAAM programs should include best practices of airway management including patient selection, assessmenct and positioning, preoxygenation strategies including apneic oxygenation, monitoring and management of physiologic abnormalities, selection of medications, post-intubation analgesia and sedation, equipment selection, airway confirmation and monitoring, and rescue airway techniques.Post-DAAM airway placement must be confirmed and continually monitored with waveform capnography.EMS clinicians must have the necessary equipment and training to manage patients with failed DAAM, including bag mask ventilation, supraglottic airway devices and surgical airway approaches.Continuous quality improvement for DAAM must include assessment of individual and aggregate performance metrics. Where available for review, continuous physiologic recordings (vital signs, pulse oximetry, and capnography), audio and video recordings, and assessment of patient outcomes should be part of DAAM continuous quality improvement.

The Association Between the Number of Prehospital Providers On-Scene and Out-of-Hospital Cardiac Arrest Outcomes.

Objective: The ideal number of emergency medical services (EMS) providers needed on-scene during an out-of-hospital cardiac arrest (OHCA) resuscitation is unknown. Our objective was to evaluate the association between the number of providers on-scene and OHCA outcomes. Methods: This was a secondary analysis of adults (≥18 years old) with non-traumatic OHCA from a 10-site North American prospective cardiac arrest registry (Resuscitation Outcomes Consortium) including a 2005-2011 cohort and a 2011-2015 cohort. The primary outcome was survival to hospital discharge. We calculated the median number of EMS providers on-scene during the first 10 minutes of the resuscitation and used multivariable logistic regression adjusting for age, sex, witness status, bystander CPR, arrest location, initial rhythm, and dispatch to EMS arrival time. Results: There were 30,613 and 41,946 patients with necessary variables in the 2005-2011 and 2011-2015 cohorts, respectively. Survival to hospital discharge (95% CI) was higher with 9 or more providers on-scene (17.2% [15.8-18.5] and 14.0% [12.6-15.4]) compared to 7-8 (14.1% [13.4-14.8] and 10.5% [9.9-11.1]), 5-6 (10.0% [9.5-10.5] and 8.5% [8.1-8.9]), 3-4 (10.5% [9.3-11.6] and 9.3% [8.5-10.1]), and 1-2 (8.6% [7.2-10.0] and 8.0% [7.1-9.0]) providers for the 2005-2011 and 2011-2015 cohorts, respectively. In multivariable logistic regressions, compared to 5-6 providers, there were no significant differences in survival to hospital discharge for 1-2 or 3-4 providers, while having 7-8 (adjusted odds ratios (aORs) 1.53 [1.39-1.67] and 1.31 [1.20-1.44]) and 9 or more (aORs 1.76 [1.56-1.98] and 1.63 [1.41-1.89]) providers were associated with improved survival in both the 2005-2011 and 2011-2015 cohorts, respectively. Conclusions: The presence of seven or more prehospital providers on-scene was associated with significantly greater adjusted odds of survival to hospital discharge after OHCA compared to fewer on-scene providers.

Fatal Sodium Nitrite Poisoning: Key Considerations for Prehospital Providers.

Sodium nitrite is a powerful oxidizing agent that causes hypotension and limits oxygen transport and delivery in the body through the formation of methemoglobin. Clinical manifestations can include cyanosis, hypoxia, altered consciousness, dysrhythmias, and death. The majority of reports on sodium nitrite poisonings have been the result of unintentional exposures. We report a case of an intentional fatal overdose of sodium nitrite. A 17-year-old female reportedly drank approximately one tablespoon of sodium nitrite in a self-harm attempt. The patient was hypotensive and cyanotic upon EMS arrival. The patient decompensated rapidly into a bradycardic arrest during transport despite intubation, push-dose epinephrine, and intravenous fluid resuscitation. In the Emergency Department (ED), she received methylene blue and packed red cells but could not be resuscitated despite a prolonged effort. EMS professionals should consider sodium nitrite toxicity in patients with a suspected overdose who present with a cyanotic appearance, pulse oximetry that remains around 85% despite oxygen, and dark brown blood seen on venipuncture. Early prehospital contact with the Poison Control Center and ED prenotification in poisoned patients is encouraged.

The 2019 Core Content of Emergency Medical Services Medicine.

On March 13, 2019 the EMS Examination Committee of the American Board of Emergency Medicine (ABEM) approved modifications to the Core Content of EMS Medicine. The Core Content is used to define the subspecialty of EMS Medicine, provides the basis for questions to be used during written examinations, and leads to development of a certification examination blueprint. The Core Content defines the universe of knowledge for the treatment of prehospital patients that is necessary to practice EMS Medicine. It informs fellowship directors and candidates for certification of the full range of content that might appear on certification examinations.

Role of Guideline Adherence in Improving Field Triage.

OBJECTIVE: To compare the sensitivity of current field triage practices for identifying high-risk trauma patients to strict guideline adherence, including changes in triage specificity, ambulance transport patterns, and trauma center volumes. METHODS: This was a pre-planned secondary analysis of an out-of-hospital prospective cohort of injured children and adults transported by 44 EMS agencies to 28 trauma and non-trauma hospitals in 7 Northwest U.S. counties from January 1, 2011 through December 31, 2011. Outcomes included Injury Severity Score (ISS) ≥16 (primary) and early critical resource use. Strict adherence of the triage guidelines was based on evidence in the EMS chart for patients meeting any current field triage criteria, calculated with and without strict interpretation of the age criterion (<15 or >55 years). Due to the probability sampling nature of the cohort, strata and weights were included in all analyses. RESULTS: 17,633 injured patients were transported by EMS (weighted to represent 53,487 transported patients), including 3.1% with ISS ≥16 and 1.7% requiring early critical resources. Field triage sensitivity for identifying patients with ISS ≥16 increased from the current 66.2% (95% CI 60.2-71.7%) to 87.3% (95% CI 81.9-91.2%) for strict adherence without age and to 91.0% (95% CI 86.4-94.2%) for strict adherence with age. Specificity decreased with increasing adherence, from 87.8% (current) to 47.6% (strict adherence without age) and 35.8% (strict adherence with age). Areas under the curve (AUC) were 0.78, 0.73, and 0.72, respectively. Results were similar for patients requiring early critical resources. We estimate the number of triage-positive patients transported each year by EMS to an individual major trauma center (on average) to increase from 1,331 (current) to 5,139 (strict adherence without age) and to 6,256 (strict adherence with age). CONCLUSIONS: The low sensitivity of current triage practices would be expected to improve with strict adherence to current triage guidelines, with a commensurate decrease in triage specificity and an increase in the number of triage-positive patients transported to major trauma centers.

An Evidence-based Guideline for the air medical transportation of prehospital trauma patients.

BACKGROUND: Decisions about the transportation of trauma patients by helicopter are often not well informed by research assessing the risks, benefits, and costs of such transport. OBJECTIVE: The objective of this evidence-based guideline (EBG) is to recommend a strategy for the selection of prehospital trauma patients who would benefit most from aeromedical transportation. METHODS: A multidisciplinary panel was recruited consisting of experts in trauma, EBG development, and emergency medical services (EMS) outcomes research. Representatives of the Federal Interagency Committee on Emergency Medical Services (FICEMS), the National Highway Traffic Safety Administration (NHTSA) (funding agency), and the Children's National Medical Center (investigative team) also contributed to the process. The panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology to guide question formulation, evidence retrieval, appraisal/synthesis, and formulate recommendations. The process followed the National Evidence-Based Guideline Model Process, which has been approved by the Federal Interagency Committee on EMS and the National EMS Advisory Council. RESULTS: Two strong and three weak recommendations emerged from the process, all supported only by low or very low quality evidence. The panel strongly recommended that the 2011 CDC Guideline for the Field Triage of Injured Patients be used as the initial step in the triage process, and that ground emergency medical services (GEMS) be used for patients not meeting CDC anatomic, physiologic, and situational high-acuity criteria. The panel issued a weak recommendation to use helicopter emergency medical services (HEMS) for higher-acuity patients if there is a time-savings versus GEMS, or if an appropriate hospital is not accessible by GEMS due to systemic/logistical factors. The panel strongly recommended that online medical direction should not be required for activating HEMS. Special consideration was given to the potential need for local adaptation. CONCLUSIONS: Systematic and transparent methodology was used to develop an evidence-based guideline for the transportation of prehospital trauma patients. The recommendations provide specific guidance regarding the activation of GEMS and HEMS for patients of varying acuity. Future research is required to strengthen the data and recommendations, define optimal approaches for guideline implementation, and determine the impact of implementation on safety and outcomes including cost.

An Evidence-based Guideline for prehospital analgesia in trauma.

BACKGROUND: The management of acute traumatic pain is a crucial component of prehospital care and yet the assessment and administration of analgesia is highly variable, frequently suboptimal, and often determined by consensus-based regional protocols. OBJECTIVE: To develop an evidence-based guideline (EBG) for the clinical management of acute traumatic pain in adults and children by advanced life support (ALS) providers in the prehospital setting. Methods. We recruited a multi-stakeholder panel with expertise in acute pain management, guideline development, health informatics, and emergency medical services (EMS) outcomes research. Representatives of the National Highway Traffic Safety Administration (sponsoring agency) and a major children's research center (investigative team) also contributed to the process. The panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology to guide the process of question formulation, evidence retrieval, appraisal/synthesis, and formulation of recommendations. The process also adhered to the National Prehospital Evidence-Based Guideline (EBG) model process approved by the Federal Interagency Council for EMS and the National EMS Advisory Council. RESULTS: Four strong and three weak recommendations emerged from the process; two of the strong recommendations were linked to high- and moderate-quality evidence, respectively. The panel recommended that all patients be considered candidates for analgesia, regardless of transport interval, and that opioid medications should be considered for patients in moderate to severe pain. The panel also recommended that all patients should be reassessed at frequent intervals using a standardized pain scale and that patients should be re-dosed if pain persists. The panel suggested the use of specific age-appropriate pain scales. CONCLUSION: GRADE methodology was used to develop an evidence-based guideline for prehospital analgesia in trauma. The panel issued four strong recommendations regarding patient assessment and narcotic medication dosing. Future research should define optimal approaches for implementation of the guideline as well as the impact of the protocol on safety and effectiveness metrics.

Out-of-hospital cardiac arrest outcomes when law enforcement arrives before emergency medical services.

BACKGROUND: Law enforcement (LE) professionals are often dispatched to out-of-hospital cardiac arrests (OHCA) to provide early cardiopulmonary resuscitation (CPR) and automated external defibrillator (AED) application with mixed evidence of a survival benefit. Our objective was to comprehensively evaluate LE care in OHCA. METHODS: This is a secondary analysis of adults with non-traumatic OHCA not witnessed by EMS and without bystander AED use from 2018-2021. Our primary outcome was survival with Cerebral Perfusion Category score ≤ 2 (functional survival). Our exposures included: LE On-scene Only (without providing care); LE CPR Only (without applying an AED); LE Ideal Care (ensuring CPR and AED application). Our control group had no LE arrival before EMS. We performed multivariable logistic regression analyses adjusting for confounders and stratified our analyses by patients with and without bystander CPR. RESULTS: There were 2569 adult, non-traumatic OHCAs from 2018-2021 meeting inclusion criteria. There were no differences in the odds of functional survival for LE On-scene Only (adjusted odds ratio [95% CI]: 1.28 [0.47-3.45]), LE CPR Only (1.26 [0.80-1.99]), or LE Ideal Care (1.36 [0.79-2.33]). In patients without bystander CPR, LE Ideal Care had significantly higher odds of functional survival (2.01 [1.06-3.81]) compared to no LE on-scene, with no significant associations for LE On-scene Only or LE CPR Only. There were no significant differences by LE care in patients already receiving bystander CPR. CONCLUSIONS: LE arrival before EMS and ensuring both CPR and AED application is associated with significantly improved functional survival in OHCA patients not already receiving bystander CPR.

The association of early naloxone use with outcomes in non-shockable out-of-hospital cardiac arrest.

STUDY OBJECTIVE: Evaluate the association between early naloxone use and outcomes after out-of-hospital cardiac arrest (OHCA) with initial non-shockable rhythms. METHODS: This study was a secondary analysis of data collected in the Portland Cardiac Arrest Epidemiologic Registry, a database containing details of emergency medical services (EMS)-treated OHCA cases in the Portland, Oregon metropolitan region. Eligible patients had non-traumatic OHCA with an initial non-shockable rhythm and received naloxone by EMS or law enforcement prior to IV/IO access (exposure group). The primary outcome was ROSC at emergency department (ED) arrival. Secondary outcomes included survival to admission, survival to hospital discharge, and cerebral performance category score ≤2 at discharge (good neurologic outcome). We performed multivariable logistic regressions adjusting for age, sex, arrest location, witness status, bystander interventions, dispatch to EMS arrival time, initial rhythm, and county of arrest. RESULTS: There were 1807 OHCA cases from 2018 to 2021 meeting eligibility criteria, with 57 receiving naloxone before vascular access. Patients receiving naloxone prior to vascular access attempts had higher adjusted odds (aOR [95% CI]) of ROSC at any time (2.14 [1.20-3.81]), ROSC at ED arrival (2.14 [1.18-3.88]), survival to admission (2.86 [1.60-5.09]), survival to discharge (4.41 [1.78-10.97]), and good neurologic outcome (4.61 [1.74-12.19]). CONCLUSIONS: Patients with initial non-shockable OHCA who received law enforcement or EMS naloxone prior to IV/IO access attempts had higher adjusted odds of ROSC at any time, ROSC at ED arrival, survival to admission, survival to discharge, and good neurologic outcome.

Variation in prehospital use and uptake of the national Field Triage Decision Scheme.

BACKGROUND: The Field Triage Decision Scheme is a national guideline that has been implemented widely for prehospital emergency medical services (EMS) and trauma systems. However, little is known about the uptake, modification, or variation in field application of triage criteria between trauma systems. OBJECTIVE: To describe and compare the use of field triage criteria by EMS personnel in six regions, including the timing of guideline uptake and the use of nonguideline criteria. METHODS: This was a retrospective cohort study of injured children and adults transported by 48 EMS agencies to 105 hospitals (trauma centers and non-trauma centers) in six Western U.S. regions from 2006 through 2008. We used probabilistic linkage to match patient-level prehospital information from multiple sources, including EMS records, base-hospital phone communication records, and trauma registry data files. Triage criteria were evaluated individually and grouped by "steps" (physiologic, anatomic, mechanism, and special considerations). We used descriptive statistics to compare the frequency of triage criteria use (overall and between regions) and to evaluate the timing of guideline uptake across multiple versions of the guidelines. RESULTS: A total of 260,027 injured patients were evaluated and transported by EMS over the three-year study period, of whom 46,414 (18%) met at least one field triage criterion and formed the primary sample for analysis. The three most common criteria cited (of 33 in use) were EMS provider judgment (26%), age <5 or >55 years (10%), and Glasgow Coma Scale (GCS) score <14 (9%). Of the 33 criteria in use, five (15%) were previously retired from the guidelines and seven (21%) were never included in the guidelines. 11,048 (24%) patients had more than one criterion applied (range 1-21). There was large variation in the type and frequency of criteria used between systems, particularly among the nonphysiologic triage steps. Only one of six regions had translated the most recent guidelines into field use within two years after release. CONCLUSION: There is large variation between regions in the frequency and type of field triage criteria used. Field uptake of guideline revisions appears to be slow and variable, suggesting opportunities for improvement in dissemination and implementation of updated guidelines.

A national assessment of the roles and responsibilities of training officers.

INTRODUCTION: Since the inception of emergency medical services (EMS), individuals have assumed the role of "training officer" without a clear and concise description of the responsibilities inherent in this position. Furthermore, EMS system leaders rely heavily on these individuals to implement changes within an EMS system and to ensure the competency of practicing out-of-hospital professionals. The limited understanding of and research in training officer roles highlight the need for study in this area. OBJECTIVES: Specific objectives of our study were to describe demographic and work-life characteristics of training officers, estimate the number of hours spent on specific training officer tasks in a typical week, and determine methods of training officer appointment and education received after appointment. METHODS: This was a questionnaire-based cross-sectional census analysis of all training officers in the National Registry of Emergency Medical Technicians (NREMT) database. This questionnaire contained items related to demographics, work-life characteristics, and specific roles and responsibilities of training officers. Descriptive statistics, chi-square, and Mann-Whitney U tests were utilized to assess specific differences among training officers. RESULTS: Over 2,500 individuals responded to this questionnaire (2,528/4,956). The majority of the respondents were male (79.0%), held a full-time salaried position (64.9%), and were of nonminority status (93.4%). Individuals reported an overall median number of years worked in EMS of 19.0 (standard deviation [SD] = 8.7, range = 0-45) and a median of 4.0 years of serving as a training officer (SD = 5.1, range = 0-33), and planned to serve as a training officer for a median of 10.0 years (SD = 7.6, range = 0-50). The highest median numbers of hours spent on specific training officer tasks in a typical week were for providing patient care (median = 8.0, SD = 18.1); developing, delivering, and accounting for continuing education (median = 5.0, SD = 9.8); department administration (median = 5.0, SD = 12.8); and performing run reviews (median = 3.0, SD = 6.4). CONCLUSION: The role of the training officer in ensuring the continued competence of the EMS professional has not been delineated in this paper, and future efforts should seek to answer this research question. Key words: emergency medical services; training officers; system administration.

Survival by time-to-administration of amiodarone, lidocaine, or placebo in shock-refractory out-of-hospital cardiac arrest.

BACKGROUND: Amiodarone and lidocaine have not been shown to have a clear survival benefit compared to placebo for out-of-hospital cardiac arrest (OHCA). However, randomized trials may have been impacted by delayed administration of the study drugs. We sought to evaluate how timing from emergency medical services (EMS) arrival on scene to drug administration affects the efficacy of amiodarone and lidocaine compared to placebo. METHOD: This is a secondary analysis of the 10-site, 55-EMS-agency double-blind randomized controlled amiodarone, lidocaine, or placebo in OHCA study. We included patients with initial shockable rhythms who received the study drugs of amiodarone, lidocaine, or placebo before achieving return of spontaneous circulation. We performed logistic regression analyses evaluating survival to hospital discharge and secondary outcomes of survival to admission and functional survival (modified Rankin scale score ≤ 3). We evaluated the samples stratified by early (<8 min) and late administration groups (≥8 min). We compared outcomes for amiodarone and lidocaine compared to placebo and adjust for potential confounders. RESULTS: There were 2802 patients meeting inclusion criteria, with 879 (31.4%) in the early (<8 min) and 1923 (68.6%) in the late (≥8 min) groups. In the early group, patients receiving amiodarone, compared to placebo, had significantly higher survival to admission (62.0% vs. 48.5%, p = 0.001; adjusted OR [95% CI] 1.76 [1.24-2.50]), survival to discharge (37.1% vs. 28.0%, p = 0.021; 1.56 [1.07-2.29]), and functional survival (31.6% vs. 23.3%, p = 0.029; 1.55 [1.04-2.32]). There were no significant differences with early lidocaine compared to early placebo (p > 0.05). Patients in the late group who received amiodarone or lidocaine had no significant differences in outcomes at discharge compared to placebo (p > 0.05). CONCLUSIONS: The early administration of amiodarone, particularly within 8 min, is associated with greater survival to admission, survival to discharge, and functional survival compared to placebo in patients with an initial shockable rhythm.

The core content of emergency medical services medicine.

On September 23, 2010, the American Board of Medical Specialties (ABMS) approved emergency medical services (EMS) as a subspecialty of emergency medicine. As a result, the American Board of Emergency Medicine (ABEM) is planning to award the first certificates in EMS medicine in the fall of 2013. The purpose of subspecialty certification in EMS, as defined by ABEM, is to standardize physician training and qualifications for EMS practice, to improve patient safety and enhance the quality of emergency medical care provided to patients in the prehospital environment, and to facilitate integration of prehospital patient treatment into the continuum of patient care. In February 2011, ABEM established the EMS Examination Task Force to develop the Core Content of EMS Medicine (Core Content) that would be used to define the subspecialty and from which questions would be written for the examinations, to develop a blueprint for the examinations, and to develop a bank of test questions for use on the examinations. The Core Content defines the training parameters, resources, and knowledge of the treatment of prehospital patients necessary to practice EMS medicine. Additionally, it is intended to inform fellowship directors and candidates for certification of the full range of content that might appear on the examinations. This article describes the development of the Core Content and presents the Core Content in its entirety.

Development of a clinical decision rule for the early prediction of Shock-Refractory Out-of-Hospital cardiac arrest.

BACKGROUND: Nearly half of ventricular fibrillation or ventricular tachycardia (VF/VT) out-of-hospital cardiac arrest (OHCA) patients receive three or more shocks, often referred to as refractory VF/VT. Our objective was to derive a clinical decision rule (CDR) for the early stratification of patients into risk categories for refractory VF/VT. METHODS: We included adults with non-traumatic OHCA in the Resuscitation Outcomes Consortium Epistry (2011-2015) with ≥ 1 EMS shock. We used Classification and Regression Tree analysis for CDR building using variables known at initial EMS rhythm analysis including age, sex, witness, location, bystander interventions, initial EMS rhythm, obvious non-cardiac etiology, and dispatch to arrival times. The outcome was refractory VF/VT (≥3 shocks). We calculated sensitivity, specificity, area under the receiver operating curve (AUROC), and odds ratios (OR). The rule was validated using the Portland Cardiac Arrest Epidemiologic Registry (2018-2020). RESULTS: There were 17,140 eligible patients and 8,146 (47.5%) had refractory VF/VT. The optimal CDR (AUROC = 0.671) defined three groups: high-risk were any patients requiring an EMS shock after a bystander AED shock; moderate-risk were any non-EMS witnessed arrests with shockable initial EMS rhythms; and the remainder were low-risk. Refractory VF/VT increased across the low (30.7%), moderate (58.5%) and high-risk (84.8%) groups. Compared to low-risk, being moderate-risk or higher (OR [95% CI]:3.37 [3.16-3.59]; sensitivity 72.7%; specificity 55.9%) or high-risk (OR:12.63 [9.89-16.13]; sensitivity 5.4%; specificity 99.1%) had higher odds of refractory VF/VT. Results was similar in the validation cohort (n = 765, AUROC = 0.672). CONCLUSIONS: Patients at higher risk for refractory VF/VT can be identified early in EMS care.

Secondary Creep Analysis of FG Rotating Cylinder with Exponential, Linear and Quadratic Volume Reinforcement.

Creep is an irreversible time-dependent deformation in which a material under constant mechanical stress and elevated temperature for a considerably prolonged period of time, starts to undergo permanent deformation. Creep deformation occurs in three stages namely, primary, secondary and tertiary. Out of these three stages, secondary or steady state creep is particularly an area of engineering interest as it has almost a constant creep rate. Creep deformation plays a significant role in understanding effective service life of an engineering component working under high temperature conditions as such components such as super-heater and re-heater tubes and headers in a boiler, jet engines operating at temperature as high as 1200 ∘C, usually experience a failure or rupture due to creep phenomenon. Design engineers keep a close attention on working stress conditions and elevated temperature under which an engineering component is expected to work as these conditions determine the onset of creep behavior in an engineering component. By recognizing the parameters of material response to creep behavior, engineers can analyse the useful service life and hazardous working conditions for an engineering components. Recognizing the creep phenomenon as high temperature design limitation, ASME Boiler and Pressure Vessel Code have provided guidelines on maximum allowable stresses for materials to be used in creep range. One of the criteria for determination of allowable stresses is 1% creep deformation of material in 100,000 h of service. Thus, the study of creep behavior in engineering components pertaining to high stress and temperature working conditions is very important as it affects the reliability and performance of the engineering components. The aim of our study is to understand the behavior of secondary creep deformation so that an advanced reinforced functionally graded material with better creep resistance, can be designed. In this paper, a secondary creep analysis of functionally graded (FG) thick-walled rotating cylinder under internal and external pressure is conducted. The novelty of the model intends to specify secondary creep stresses and strains by employing exponential, linear and quadratic volume reinforcement for SiCp ceramic in Al metal matrix in radial direction. This will help us to understand the effect of volume reinforcement in FG cylinder under internal/external pressure and rotating centrifugal body force by obtaining secondary creep stresses and strains. The response of the FG cylinder with isotropic material is analyzed and the solution for stress-strain rates in radial and tangential directions are obtained in closed form. Comparison of steady state creep stresses and strains under exponential, linear and quadratic volume reinforcement profiles are discussed and presented graphically.

Developing a statewide emergency medical services database linked to hospital outcomes: a feasibility study.

BACKGROUND: Statewide emergency medical services (EMS) data linked to outcomes are critical for promoting high-quality emergency care; however, many states do not have such a resource. OBJECTIVE: To demonstrate the feasibility of creating such a statewide database using a one-month pilot sample. METHODS: This was a prospective cohort study of all EMS patient encounters throughout Oregon during May 2008. Eighty-three National EMS Information System (NEMSIS) variables were obtained from EMS agencies via electronic or paper charts. We reformatted raw data, mapped NEMSIS fields, entered hard-copy records, and uploaded data files to a statewide electronic medical records platform. Records from transport and nontransport (first-responder) agencies caring for the same patients were matched using probabilistic linkage, then linked to three statewide outcome databases (Oregon Hospital Discharge Database [OHDD], Oregon Trauma Registry [OTR], and Oregon Department of Transportation [ODOT] Crash File) using similar methodology. We estimated population-adjusted case ascertainment by county and used descriptive statistics to characterize the process. RESULTS: During the one-month period, we collected 27,474 EMS records in 36 (100%) counties from 106 (77%) licensed transport agencies and 10 nontransport agencies, representing 20,673 persons. There were 3,302 admission record matches, 285 trauma registry matches, and 392 crash record matches. Overall, 3,979 hospital outcomes were matched to EMS records for 80 (75%) transport and six (60%) first-responder agencies. Median per-agency match rates were 16.3% for OHDD (interquartile range [IQR] 8.3-22.2%, range 0-56.5%), 0.9% for OTR (IQR 0-2.5%, range 0-60.0%), and 1.6% for ODOT (IQR 0-3.5%, range 0-23.1%). CONCLUSION: Developing a statewide EMS database linked to hospital outcomes is feasible. The processes used in this study and match rate estimates may provide a template for other states to follow, enhancing opportunities for outcomes-based EMS research and EMS quality assurance efforts.