The Use of Epinephrine for Out-Of-Hospital Treatment of Anaphylaxis

Abstract

The National Association of EMS Physicians (NAEMSP) believes that all levels of emergency medical services (EMS) providers should be allowed to carry and administer epinephrine for the treatment of anaphylaxis. This document is the official position of the NAEMSP.     

Epinephrine use and outcomes in anaphylaxis patients transported by emergency medical services

Background

Anaphylaxis is a potentially life-threatening allergic reaction that may require emergency medical system (EMS) transport. Fatal anaphylaxis is associated with delayed epinephrine administration. Patient outcome data to assess appropriateness of EMS epinephrine administration are sparse.

Objectives

The objectives of this study are to (1) determine the frequency of epinephrine administration in EMS-transported patients with allergic complaints, (2) identify predictors of epinephrine administration, and (3) determine frequency of emergency department (ED) epinephrine administration after EMS transport.

Methods

A cohort study was conducted from over 5 years. A total of 59 187 EMS transports of an Advanced Life Support (ALS) ambulance service were studied.

Results

One hundred and three patient transports for allergic complaints were analyzed. Fifteen patients received EMS epinephrine, and epinephrine was recommended for 2 additional patients who refused, for a total of 17 (17%) patients for whom epinephrine was administered or recommended. Emergency medical system epinephrine administration or recommendation was associated with venom as a trigger (29% vs 8%; odds ratio [OR], 4.70; 95% confidence interval [CI], 1.28-17.22; P = .013), respiratory symptoms (88% vs 52%; OR, 6.83; 95% CI, 1.47-31.71; P = .006), and fulfillment of anaphylaxis diagnostic criteria (82% vs 49%; OR, 3.50; 95% CI, 0.94-13.2; P = .0498). Four (4%) patients received epinephrine after ED arrival.

Conclusion

Low rates of epinephrine administration were observed. The association of EMS administration of epinephrine with respiratory symptoms, fulfillment of anaphylaxis diagnostic criteria, and low rate of additional epinephrine administration in the ED suggest that ALS EMS administered epinephrine based on symptom severity. Additional studies of EMS anaphylaxis management including ED management and outcomes are needed.     

Emergency Call Characteristics and EMS Dispatcher Protocol Adherence for Possible Anaphylaxis

Objective: Anaphylaxis is a medical emergency requiring prompt recognition and treatment with intramuscular epinephrine to optimize outcomes. To date, there is a paucity of data regarding the demographic characteristics of the subset of patients calling 9-1-1 for allergic reactions and the emergency medical services (EMS) dispatcher's adherence to national protocols for their response to a suspected allergic reaction. Methods: We conducted a retrospective review of dispatch calls to a local municipality that were dispatched with an impression of an “allergic reaction” or “difficulty breathing related to a suspected allergic reaction” from January 2016 to June 2016. Using a modified Delphi approach, the voice recordings of the calls were reviewed for EMS dispatcher adherence to the Medical Priority Dispatch System v12.2 (2012) triage questions and pre-arrival instructions for the Allergies/Envenomations and Breathing Problems protocols. The calls were further reviewed for demographic characteristics, symptomatology, history of allergy, suspected trigger of the current reaction, and use and availability of medications. Calls were also classified as to whether the patient met criteria for anaphylaxis. We calculated frequencies for categorical measures and medians with ranges for continuous measures. Results: A total of 146 calls met inclusion criteria. The median age of patients was 29 years (interquartile range 13, 52). 12.3% (n?=?18) of the calls reviewed were consistent with national standards for anaphylaxis. Food was the most commonly reported historical allergy, whereas medication accounted for the most commonly suspected trigger for the current symptoms. The EMS dispatcher asked about alertness, difficulty breathing, difficulty speaking, and color change in 39.7, 80.1, 12.3, and 2.7% of calls, respectively. While 56.2% of dispatchers inquired about a history of severe allergy, only 16.4% inquired about prescribed special injections. Conclusions: The majority of calls were not consistent with anaphylaxis, and EMS dispatchers rarely strictly followed the Medical Priority Dispatch System guidelines aimed at identifying anaphylaxis. Future studies would be beneficial to determine if our findings hold true in other EMS service areas.     

Syringe Administration of Epinephrine by Emergency Medical Technicians for Anaphylaxis

Objective: In recent years, the costs of epinephrine autoinjectors (EAIs) in the United States have risen substantially. King County Emergency Medical Services implemented the “Check and Inject” program to replace EAIs by teaching emergency medical technicians (EMTs) to manually aspirate epinephrine from a single-use 1 mg/mL epinephrine vial using a needle and syringe followed by prehospital intramuscular administration of the correct adult or pediatric dose of epinephrine for anaphylaxis or serious allergic reaction. Treatment was guided by an EMT protocol that required a trigger and symptoms. We sought to determine if the “Check and Inject” program was safely implemented by EMTs treating presumed prehospital anaphylaxis or serious allergic reaction. Methods: We conducted a prospective investigation of all cases treated as part of the “Check and Inject” program from July 2014 through December 2016 in suburban King County, Washington, and January 2016 through December 2016 within the city of Seattle. All cases were prospectively collected using a custom quality improvement data form completed by the first responding EMTs. Two physicians completed a structured review of each EMS medical record to determine if the EMTs followed the Check and Inject protocol and determine if epinephrine was clinically-indicated based on physician review. Results: Of the 411 cases eligible for analysis, EMTs followed the protocol appropriately in 367 (89.3%) cases. In the remaining 44 (10.7%) cases, the EMS incident report form failed to document either a clear inciting allergic trigger or an appropriate symptom from the protocol list. Physician review determined that epinephrine was clinically indicated in 36 of the 44 cases. Among the remaining 8 cases (1.9%) that did not meet protocol criteria and were not clinically-indicated based on physician review, none had a documented adverse reaction to the epinephrine. Conclusion: We observed that EMTs successfully implemented the manual “Check and Inject” program for severe allergic reactions and anaphylaxis in a manner that typically agreed with physician review and without any overt identified safety issues.     

Epinephrine use by emergency medical technicians for presumed anaphylaxis

Objective

The use of epinephrine for the treatment of anaphylaxis by emergency medical technicians (EMTs) has not been rigorously evaluated. The aim of this study was to determine whether first-tier EMTs use epinephrine safely and appropriately for anaphylactic reactions.

Methods

The study used a case-control design. Cases were persons treated by EMTs with epinephrine for presumed anaphylaxis from January 1, 2000, through January 31, 2003, in King County, Washington (n = 22). Controls were emergency medical services (EMS)-treated persons matched to cases by diagnosis category, patient age, fire department, and year, but who had not been administered epinephrine by EMTs (n = 44). Cases and controls were compared with regard to history, symptoms, and examination characteristics. In a second assessment, physicians blinded to treatment (case/control) status reviewed events to determine whether they would have treated the patient with epinephrine.

Results

When cases were compared with controls, cases were more likely to report a history of anaphylaxis (27% vs. 2%), upper airway symptoms (59% vs. 18%), and shortness of breath (77% vs. 27%). Cases were also more likely to have tachypnea (32% vs. 5%), hypotension (41% vs. 9%), decreased level of consciousness (32% vs. 2%), abnormal breath sounds (46% vs. 16%), and rash (50% vs. 23%) (p ≤ 0.01 for all comparisons). The physicians agreed with the EMTs' decisions regarding epinephrine use (or nonuse) in 86% (57/66) of events: 86% (19/22) in which the EMTs used epinephrine and 86% (38/44) in which the EMTs did not use epinephrine.

Conclusion

In this EMS system, the EMTs used epinephrine for presumed anaphylaxis in a discriminating manner that typically agreed with physician review.     

Prehospital Administration of Epinephrine in Pediatric Anaphylaxis

Anaphylaxis in the pediatric population is both serious and potentially lethal. The incidence of allergic and anaphylactic reactions has been increasing and the need for life saving intervention with epinephrine must remain an important part of Emergency Medical Services (EMS) provider training. Our aim was to characterize dosing and timing of epinephrine, diphenhydramine, and albuterol in the pediatric patient with anaphylaxis. In this retrospective chart review, we studied prehospital medication administration in pediatric patients ages 1 month up to 14 years old classified as having a severe allergic reaction or anaphylaxis. We compared rates of epinephrine, diphenhydramine, and albuterol given to patients with allergic conditions including anaphylaxis. In addition, we calculated the rate of epinephrine administration in cases of anaphylaxis and determined what percentage of time the epinephrine was given by EMS or prior to their arrival. Of the pediatric patient contacts, 205 were treated for allergic complaints. Of those with allergic complaints, 98 of 205 (48%; 95% CI 41%, 55%) had symptoms consistent with anaphylaxis and indications for epinephrine. Of these 98, 53 (54%, 95% CI 44%, 64%) were given epinephrine by EMS or prior to EMS arrival. Among the patients in anaphylaxis not given epinephrine prior to EMS arrival, 6 (12%; 95% CI 3%, 21%) received epinephrine from EMS, 10 (20%; 95% CI 9%, 30%) received diphenhydramine only, 9 (18%, 95% CI 7%–28%) received only albuterol and 17 (33%, 95% CI 20%–46%) received both albuterol and diphenhydramine. 9 patients in anaphylaxis received no treatment prior to arriving to the emergency department (18%, 95% CI 7%–28%). In pediatric patients who met criteria for anaphylaxis and the use of epinephrine, only 54% received epinephrine and the overwhelming majority received it prior to EMS arrival. EMS personnel may not be treating anaphylaxis appropriately with epinephrine.     

EMS Provider Determinations of Necessity for Transport and Reimbursement for EMS Response,Medical Care,and Transport: Combined Resource Document for the National Association of EMS Physicians Position Statements

Abstract

With increasing demands for emergency medical services (EMS), many EMS jurisdictions are utilizing EMS provider-initiated nontransport policies as a method to offload potentially nonemergent patients from the EMS system. EMS provider determination of medical necessity, resulting in nontransport of patients, has the potential to avert unnecessary emergency department visits. However, EMS systems that utilize these policies must have additional education for the providers, a quality improvement process, and active physician oversight. In addition, EMS provider determination of nontransport for a specific situation should be supported by evidence in the peer-reviewed literature that the practice is safe. Further, EMS systems that do not utilize these programs should not be financially penalized. Payment for EMS services should be based on the prudent layperson standard. EMS systems that do utilize nontransport policies should be appropriately reimbursed, as this represents potential cost savings to the health care system.     

Appropriate use of epinephrine in anaphylaxis

We are submitting a case-based presentation illustrating medical errors in the use of epinephrine for the treatment of anaphylaxis. Readers will learn from mistakes made by other emergency caregivers in treating anaphylaxis. The article will specifically review the recommended use of epinephrine in the management of anaphylaxis. Four patients are presented who were seen in consultation by our outpatient allergy service. In all 4 cases, the history was suggestive of an episode of anaphylaxis in which emergency care providers mismanaged treatment. In 2 cases, the patients required ICU care after improperly receiving intravenous epinephrine. In the remaining 2 cases, epinephrine use was either omitted or significantly delayed in its administration. Our presentation includes a review of consensus statements regarding the treatment of anaphylaxis with particular regard to the use of epinephrine. We hope that this information will help prevent similar errors from harming other patients.     

Termination of Resuscitation for Adult Traumatic Cardiopulmonary Arrest

Abstract

The National Association of EMS Physicians (NAEMSP) and the American College of Surgeons Committee on Trauma (ACS-COT) believe that emergency medical services (EMS) systems should have protocols that allow EMS providers to terminate resuscitative efforts for certain adult patients in traumatic cardiopulmonary arrest. This document is the official position of the NAEMSP and ACS-COT.     

Patient perceptions of epinephrine auto‐injectors: exploring barriers to use

Scand J Caring Sci; 2013; 27; 335–344 Patient perceptions of epinephrine auto‐injectors: exploring barriers to use Background: In recent years, government initiatives have proposed that patient self‐care should serve as a key resource in response to the anticipated increase in global demand for health care. However, if patients are to be empowered as self‐carers, barriers to engagement must be identified and overcome. Anaphylaxis is an increasingly common life‐threatening allergic reaction. Patients at risk of anaphylaxis are prescribed epinephrine auto‐injectors and play a crucial role in delivering their own care and management of this condition. One key recommendation is that patients routinely carry an epinephrine auto‐injector with them and deploy the device when needed. However, only a small proportion of patients that require epinephrine actually receive it. Objective: To explore the reasons why patients who have been prescribed epinephrine auto‐injectors fail to adhere to self‐care and management recommendations. Methods: In‐depth interviews with 15 adults who have been prescribed epinephrine auto‐injectors were carried out to explore the barriers that exist in the provision of effective self‐care and management of anaphylaxis. Results: Inconsistent health professional advice, perceived stigma of carrying a ‘weapon‐like’ device, poor device design and limited patient training were identified as barriers to carriage or use. Patients were reluctant to carry devices in public because of perceived and observed stigma and suspicion. They were happy to ignore expiry dates, and some participants were confident that the emergency services would provide them with the appropriate care they needed, and therefore, did not carry the device in urban areas. Conclusions and clinical implications: Improved training of patients, the public and health professionals around both the carriage and use of auto‐injectors are areas for urgent attention if improved levels of self‐care are to be attained. The design of epinephrine auto‐injectors should also receive attention as patients often fail to carry them owing to size and aesthetics.     

Cold Anaphylaxis: A Case Report

BackgroundCold anaphylaxis is a severe form of hypersensitivity reaction to cold temperatures. Such reactions include a spectrum of presentations that range from localized symptoms to systemic involvement. The condition can be acquired or heritable, although it may also be idiopathic. Treatment consists of second-generation H₁ antihistamines, epinephrine, and supportive care. Prevention involves avoidance of known triggers, most commonly cold immersion due to environment or water exposure.Case ReportWe report the case of a 34-year-old man with cold-induced urticaria/anaphylaxis who presented to our emergency department with hypotension and shortness of breath after exposure to cold air after getting out of a shower. He required two doses of intramuscular epinephrine and was ultimately started on an epinephrine infusion. He was admitted to the intensive care unit for anaphylaxis monitoring and was found to have a positive ice cube test, reinforcing the suspected diagnosis.Why Should An Emergency Physician Be Aware of This?Cold anaphylaxis is a potentially life-threatening phenomenon with specific testing. It is occasionally described in the emergency medicine literature. Providers should be aware of the potential for cold anaphylaxis as it can change patient guidance and alter management. This condition can also contribute to otherwise unclear and sudden decompensation in critically ill patients, as has been reported in cases of cold anaphylaxis induced by cold IV infusions.     

Emergency medicine updates: Anaphylaxis

IntroductionAnaphylaxis is a potentially deadly condition that requires emergent therapy. While frequently treated in the emergency department (ED), recent evidence updates may improve the diagnosis and management of this condition.ObjectiveThis paper evaluates key evidence-based updates concerning the diagnosis and management of anaphylaxis for the emergency clinician.DiscussionThe presentation of anaphylaxis can vary. Current diagnostic criteria can be helpful when evaluating patients for anaphylaxis, though multiple criteria exist. While the most common causes of anaphylaxis include medications, insect venom, and foods, recent literature has identified an IgE antibody response to mammalian galactose alpha-1,3-galactose, known as alpha-gal anaphylaxis. Epinephrine is the first-line therapy and is given in doses of 0.01 mg/kg (up to 0.5 mg in adults) intramuscularly (IM) in the anterolateral thigh. Intravenous (IV) epinephrine administration is recommended in patients refractory to IM epinephrine and IV fluids, or those with cardiovascular collapse. Antihistamines and glucocorticoids should not delay administration of epinephrine and do not demonstrate a significant reduction in risk of biphasic reactions. Biphasic reactions may affect 1–7% of patients with anaphylaxis. Risk factors for biphasic reaction include severe initial presentation and repeated doses of epinephrine. Disposition of patients with anaphylaxis requires consideration of several factors.ConclusionsEmergency clinicians must be aware of current updates in the evaluation and management of this disease.     

Validation of field assessment stroke triage for emergency destination for prehospital use in a rural EMS system

BackgroundField Assessment Stroke Triage for Emergency Destination (FAST-ED) is a simple and accurate prehospital stroke severity scale that has been shown to have comparable accuracy to the gold standard National Institutes of Health Stroke Scale (NIHSS) but requires further field validation for use by emergency medical services (EMS), particularly in rural systems. FAST-ED scores ≥4 are considered high probability for large vessel occlusion (LVO) strokes, while scores <4 are low to moderate probability for LVO. The objective of this study was to assess inter-rater reliability of the EMS FAST-ED (EMS) score to the emergency department FAST-ED (ED-MD) scores.MethodsEMS calculated FAST-ED scores prior to transport to the emergency department (ED) on patients with a positive prehospital stroke screen. EDMD calculated FAST-ED scores for the same patients upon arrival to the ED. Interrater reliability and test characteristics were calculated.ResultsA total of 95 patients were included in this study and 14 were subsequently diagnosed with an LVO. EMS assigned 34 patients (35.8%) a FAST-ED score of ≥4. EDMD assigned 25 patients (26.3%) a FAST-ED score of ≥4. Using the clinical cut-points of FAST-ED scores <4 and ≥ 4, a linearly weighted Cohen's kappa coefficient showed moderate interrater reliability when comparing EMS and EDMD scores (k_w 0.44, 95% CI 0.25–0.63). At ≥4, EMS FAST-ED scores had a sensitivity 0.48, specificity 0.75, PPV 0.62, NPV 0.62 for predicting an LVO, while EDMD FAST-ED scores had a sensitivity 0.36, specificity 0.82, PPV 0.64, NPV 0.60. Comparable receiver operator curve area under the curve values were obtained.ConclusionsEMS and EDMD FAST-ED scores were moderately comparable in a rural EMS system. Similar NPVs compared to EDMD suggest the use of FAST-ED as an appropriate screening tool for EMS to predict the probability of LVO in the prehospital setting and make destination determinations regarding primary transport to a thrombectomy-capable stroke center.     

Anaphylaxis Knowledge Among Paramedics: Results of a National Survey

Abstract

Background. Very little is known about prehospital providers’ knowledge regarding anaphylaxis care. Objectives. The purpose of this study was to evaluate how well nationally registered paramedics in the United States recognize classic and atypical presentations of anaphylaxis. We also assessed knowledge regarding treatment with epinephrine, including dosing, route of administration, and perceived contraindications to epinephrine use. Methods. This was a blinded, cross-sectional online survey of a random sample of paramedics registered by the National Registry of Emergency Medical Technicians that was distributed via e-mail. The survey contained two main sections: demographic data/self-assessment of confidence with anaphylaxis care and a cognitive assessment. Results. A total of 3,537 paramedics completed the survey, for a 36.6% response rate. Among the respondents, 98.9% correctly recognized a case of classic anaphylaxis, whereas only 2.9% correctly identified the atypical presentation. Regarding treatment, 46.2% identified epinephrine as the initial drug of choice; 38.9% chose the intramuscular (IM) route of administration, and 60.5% identified the deltoid as the preferred location (11.6% thigh). Of the respondents, 98.0% were confident they could recognize anaphylaxis; 97.1% were confident they could manage anaphylaxis; 39.5% carry epinephrine autoinjectors (EAIs) on response vehicles; 95.4% were confident they could use an EAI; and 36.2% stated that there were contraindications to epinephrine administration in anaphylactic shock. Conclusions. Whereas a large percentage of the paramedics recognized classic anaphylaxis, a very small percentage recognized atypical anaphylaxis. Less than half chose epinephrine as the initial drug of choice, and most respondents were unable to identify the correct route/location of administration. This survey identifies a number of areas for improved education.