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 59187 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.

Antihypertensive medication use is associated with increased organ system involvement and hospitalization in emergency department patients with anaphylaxis.

BACKGROUND: Risk factors for increased anaphylaxis severity are poorly understood. Angiotensin-converting enzyme (ACE) inhibitors have been associated with severe anaphylactic reactions in patients with hymenoptera venom allergy. Studies evaluating the association between beta-blockers and severe anaphylaxis have been conflicting. OBJECTIVE: To evaluate the association between antihypertensive medication use and increased anaphylaxis severity. METHODS: We included emergency department anaphylaxis patients aged 18 years and older. Markers of severe anaphylaxis were defined as (1) syncope, hypotension, or hypoxia; (2) signs and symptoms involving 3 or more organ systems; and (3) hospitalization. Antihypertensive medications evaluated included beta-blockers, ACE inhibitors, calcium channel blockers, angiotensin receptor blockers, and diuretics. Simple and multiple logistic regression analyses were conducted to estimate the association between antihypertensive medication use and markers of increased anaphylaxis severity. RESULTS: Among 302 patients with anaphylaxis, 55 (18%) had syncope, hypoxia, or hypotension, 57 (19%) required hospitalization, and 139 (46%) had 3 or more organ system involvement. After adjusting for age, gender, suspected trigger, and preexisting lung disease, beta-blocker, ACE-inhibitor, diuretic, or antihypertensive medication use in aggregate remained associated with both 3 or more organ system involvement and need for hospital admission. The adjusted associations between antihypertensive medication use in aggregate and 3 or more organ system involvement yielded an odds ratio of 2.8 (95% CI, 1.5-5.2; P=.0008) and with hospitalization an odds ratio of 4.0 (95% CI, 1.9-8.4; P=.0001). CONCLUSIONS: In emergency department anaphylaxis patients, antihypertensive medication use is associated with increased organ system involvement and increased odds of hospital admission, independent of age, gender, suspected trigger, or preexisting lung disease.

Evaluation of national institute of allergy and infectious diseases/food allergy and anaphylaxis network criteria for the diagnosis of anaphylaxis in emergency department patients.

BACKGROUND: Diagnostic criteria were proposed at the Second Symposium on the Definition and Management of Anaphylaxis convened by the National Institute of Allergy and Infectious Diseases/Food Allergy and Anaphylaxis Network (NIAID/FAAN). Validation is needed before these criteria can be widely adapted into clinical practice. OBJECTIVE: Our aim was to retrospectively assess the diagnostic accuracy of the NIAID/FAAN criteria for the diagnosis of anaphylaxis in emergency department (ED) patients. METHODS: A retrospective cohort study of ED patients presenting from April to October 2008 was conducted. Patients given a diagnosis of an allergic reaction or anaphylaxis and a subset of patients with related diagnoses were included. Electronic medical records were reviewed and data were abstracted to determine whether the NIAID/FAAN criteria were met. Records were also independently reviewed in a blinded fashion by 2 experienced attending allergists. Final diagnosis by allergists was considered the reference standard. RESULTS: Of 214 patients, 86 (40.2%) met the NIAID/FAAN criteria for anaphylaxis. Allergists gave 61 (28.5%) patients diagnoses of anaphylaxis, 59 (96.7%) of whom satisfied the NIAID/FAAN criteria. The interrater agreement between allergists was substantial (κ = 0.77). The test characteristics of the NIAID/FAAN criteria were as follows: sensitivity, 96.7% (95% CI, 88.8% to 99.1%); specificity, 82.4% (95% CI, 75.5% to 87.6%); positive predictive value, 68.6% (95% CI, 58.2% to 77.4%); negative predictive value, 98.4% (95% CI, 94.5% to 99.6%); positive likelihood ratio, 5.48; and negative likelihood ratio, 0.04. CONCLUSIONS: These results suggest that the NIAID/FAAN criteria are highly sensitive but less specific and are likely to be useful in the ED for the diagnosis of anaphylaxis.

Epinephrine auto-injector pandemic.

Epinephrine is crucial in the treatment of anaphylaxis. As anaphylaxis frequently occurs in nonmedical settings, use of an epinephrine auto-injector is vital for prompt management. This article provides an overview of the increasing number of epinephrine auto-injector prescriptions and the underlying causes and contributing factors to these rising prescriptions. It also reviews the current indications for prescription of an epinephrine auto-injector, proper use of epinephrine auto-injectors, and the management of unintentional epinephrine injections.

Prescriptions for self-injectable epinephrine in emergency department angioedema management.

BACKGROUND: Angioedema is often treated in the emergency department (ED). Few studies have evaluated self-injectable epinephrine (SIE) prescribing patterns for angioedema. OBJECTIVES: To describe presentation and management of ED patients with angioedema and determine factors associated with epinephrine administration, hospital admission and SIE prescription. METHODS: We conducted a retrospective cohort study of all ED patients with angioedema between January 2005 and December 2006. RESULTS: Of 63 patients, 39 (61.9%) were female. Median age was 49 years. Precipitating factors were identified in 36 (57.1%) patients. History of other allergic conditions was seen in 37 (58.7%) patients. Seventeen (27.0%) patients received epinephrine, 55 (87.3%) received antihistamines, and 51 (81.0%) received steroids. Epinephrine was administered more commonly in patients with edema of the tongue (risk ratio [RR], 5.28, 95% confidence interval [CI] 1.95-14.33, P = .0003), tightness/fullness of throat (RR, 3.31, 95% CI 1.62-6.76, P = .006), and dyspnea/wheeze (RR, 3.04, 95% CI 1.41-6.59, P = .005). Hospitalization was more common in patients with dyspnea/wheeze (P = .028) and allergic history (P = .006). Thirteen patients (22.0%) were discharged with SIE. An SIE prescription was associated with younger patients (median age, 26 years [interquartile range (IQR) 15-50] vs a median age 57.5 years [IQR 43-68], P = .004) and patients with throat tightness/fullness (RR, 4.2, 95% CI 1.8-9.8, P = .005). CONCLUSION: Patients with respiratory symptoms and allergic history were likely to be admitted. Epinephrine use was more frequent in patients with signs and symptoms of oropharyngeal edema. Younger patients and those with tightness/fullness of throat were likely to be prescribed SIE. Further studies are needed to determine who would benefit from epinephrine use and SIE prescription.

Anaphylaxis in emergency department patients 50 or 65 years or older.

BACKGROUND: Anaphylaxis is a potentially life-threatening allergic reaction commonly managed in the emergency department (ED). Data describing patients 50 or 65 years or older with anaphylaxis are limited. OBJECTIVE: To describe the presentation and management of patients with anaphylaxis who were 50 or 65 years or older and to compare these findings with those of younger patients. METHODS: A consecutive cohort study of patients presenting to an ED with approximately 80,000 visits per year was conducted. Patients who met diagnostic criteria for anaphylaxis from April 2008 to June 2010 were included. Data were collected on suspected causes, signs and symptoms, management, ED disposition, and follow-up. RESULTS: The study included 220 patients. Food was the most common suspected cause of anaphylaxis for patients younger than 50 (42.2%) or 65 years (38.5%) but was much less common in patients 50 (14.8%, P < .001) or 65 years or older (14.3%, P = .01). Cardiovascular symptoms were more likely to occur in older patients (≥50 years old, 55.6% vs 30.1%, P < .001; ≥65 years old, 64.3% vs 32.3%, P = .002). Patients 50 or 65 years or older were less likely to be dismissed home directly from the ED (≥50 years old, 35.2% vs 56.6%, P = .006; ≥65 years old, 32.1% vs 54.2%, P = .03) and were less likely to be prescribed self-injectable epinephrine (≥50 years old, 40.7% vs 63.3%, P = .004; ≥65 years old, 32.1% vs 61.5%, P = .003). CONCLUSIONS: In ED patients presenting with anaphylaxis, age of 50 or 65 years or older is associated with a decreased likelihood of food-induced anaphylaxis, increased likelihood of experiencing cardiovascular symptoms, decreased dismissal to home directly from the ED, and decreased prescriptions for self-injectable epinephrine.

An assessment of the incremental value of the ABCD2 score in the emergency department evaluation of transient ischemic attack.

STUDY OBJECTIVE: We study the incremental value of the ABCD2 score in predicting short-term risk of ischemic stroke after thorough emergency department (ED) evaluation of transient ischemic attack. METHODS: This was a prospective observational study of consecutive patients presenting to the ED with a transient ischemic attack. Patients underwent a full ED evaluation, including central nervous system and carotid artery imaging, after which ABCD2 scores and risk category were assigned. We evaluated correlations between risk categories and occurrence of subsequent ischemic stroke at 7 and 90 days. RESULTS: The cohort consisted of 637 patients (47% women; mean age 73 years; SD 13 years). There were 15 strokes within 90 days after the index transient ischemic attack. At 7 days, the rate of stroke according to ABCD2 category in our cohort was 1.1% in the low-risk group, 0.3% in the intermediate-risk group, and 2.7% in the high-risk group. At 90 days, the rate of stroke in our ED cohort was 2.1% in the low-risk group, 2.1% in the intermediate-risk group, and 3.6% in the high-risk group. There was no relationship between ABCD2 score at presentation and subsequent stroke after transient ischemic attack at 7 or 90 days. CONCLUSION: The ABCD2 score did not add incremental value beyond an ED evaluation that includes central nervous system and carotid artery imaging in the ability to risk-stratify patients with transient ischemic attack in our cohort. Practice approaches that include brain and carotid artery imaging do not benefit by the incremental addition of the ABCD2 score. In this population of transient ischemic attack patients, selected by emergency physicians for a rapid ED-based outpatient protocol that included early carotid imaging and treatment when appropriate, the rate of stroke was independent of ABCD2 stratification.

Emergency Department hyperglycemia as a predictor of early mortality and worse functional outcome after intracerebral hemorrhage.

BACKGROUND: We have previously reported the association of hyperglycemia and mortality after ischemic stroke. This study attempts to answer the hypothesis, if hyperglycemia at arrival, is associated with early mortality and functional outcome in patients with acute non-traumatic intracerebral hemorrhage (ICH). METHODS: The study cohort consisted of 237 patients who presented to the ED with ICH and had blood glucose measured on ED presentation. The presence of hyperglycemia on presentation was correlated with outcome measures including volume of hematoma, intraventricular extension of hematoma (IVE), stroke severity, functional outcome at discharge, and date of death. RESULTS: Of the cohort of 237 patients, a total of 47 patients had prior history of Diabetes Mellitus (DM). Median blood glucose at presentation was 140 mg/dl (Inter-quartile range 112-181 mg/dl). DM patients had higher glucose levels on arrival (median 202 mg/dl for DM vs. 132.5 mg/dl for non-DM, P < 0.0001). Higher blood glucose at ED arrival was associated with early mortality in both non-diabetics and diabetics (P < 0.0001). Higher blood glucose was associated with poor functional outcome in non-DM patients(P < 0.0001) but not in DM patients (P = 0.268). In the logistic regression model, after adjustment for stroke severity, hematoma volume, and IVE of hemorrhage, higher initial blood glucose was a significant predictor of death (P = 0.0031); as well as bad outcome in non-DM patients (P = 0.004). CONCLUSIONS: Hyperglycemia on presentation in non-diabetic patients is an independent predictor of early mortality and worse functional outcome in patients with intracerebral hemorrhage.

The etiology and incidence of anaphylaxis in Rochester, Minnesota: a report from the Rochester Epidemiology Project.

BACKGROUND: Reported incidences of anaphylaxis range from 3.2 to 20 per 100,000 population. The incidence and trend over time has meaningful public health implications but has not been well characterized because of a lack of a standard definition and deficiencies in reporting of events. OBJECTIVE: We sought to determine the incidence and cause of anaphylaxis over a 10-year period. METHODS: We performed a population-based incidence study that was conducted in Rochester, Minnesota, from 1990 through 2000. Anaphylaxis episodes were identified on the basis of symptoms and signs of mast cell and basophil mediator release plus mucocutaneous, gastrointestinal tract, respiratory tract, or cardiovascular system involvement. RESULTS: Two hundred eleven cases of anaphylaxis were identified (55.9% in female subjects). The mean age was 29.3 years (SD, 18.2 years; range, 0.8-78.2 years). The overall age- and sex-adjusted incidence rate was 49.8 (95% CI, 45.0-54.5) per 100,000 person-years. Age-specific rates were highest for ages 0 to 19 years (70 per 100,000 person-years). Ingested foods accounted for 33.2% (70 cases), insect stings accounted for 18.5% (39 cases), medication accounted for 13.7% (29 cases), radiologic contrast agent accounted for 0.5% (1 case), "other" causes accounted for 9% (19 cases), and "unknown" causes accounted for 25.1% (53 cases). The "other" group included cats, latex, cleaning agents, environmental allergens, and exercise. There was an increase in the annual incidence rate during the study period from 46.9 per 100,000 persons in 1990 to 58.9 per 100,000 persons in 2000 (P = .03). CONCLUSION: The overall incidence rate is 49.8 per 100,000 person-years, which is higher than previously reported. The annual incidence rate is also increasing. Food and insect stings continue to be major inciting agents for anaphylaxis.

A multifaceted intervention for patients with anaphylaxis increases epinephrine use in adult emergency department.

BACKGROUND: Studies have documented inconsistent emergency anaphylaxis care and low compliance with published guidelines. OBJECTIVE: To evaluate anaphylaxis management before and after implementation of an emergency department (ED) anaphylaxis order set and introduction of epinephrine autoinjectors, and to measure the effect on anaphylaxis guideline adherence. METHODS: A cohort study was conducted from April 29, 2008, to August 9, 2012. Adult patients in the ED who were diagnosed with anaphylaxis were included. ED management, disposition, self-injectable epinephrine prescriptions, allergy follow-up, and incidence of biphasic reactions were evaluated. RESULTS: The study included 202 patients. The median age of the patients was 45.3 years (interquartile range, 31.3-56.4 years); 139 (69%) were women. Patients who presented after order set implementation were more likely to be treated with epinephrine (51% vs 33%; odds ratio [OR] 2.05 [95% CI, 1.04-4.04]) and admitted to the ED observation unit (65% vs 44%; OR 2.38 [95% CI, 1.23-4.60]), and less likely to be dismissed home directly from ED (16% vs 29%, OR 0.47 [95% CI, 0.22-1.00]). Eleven patients (5%) had a biphasic reaction. Of these, 5 (46%) had the biphasic reaction in the ED observation unit; 1 patient was admitted to the intensive care unit. Six patients (55%) had reactions within 6 hours of initial symptom resolution, of whom 2 were admitted to the intensive care unit. CONCLUSIONS: Significantly higher proportions of patients with anaphylaxis received epinephrine and were admitted to the ED observation unit after introduction of epinephrine autoinjectors and order set implementation. Slightly more than half of the biphasic reactions occurred within the recommended observation time of 4 to 6 hours. Analysis of these data suggests that the multifaceted approach to changing anaphylaxis management described here improved guideline adherence.

Effect of anticoagulant and antiplatelet therapy in patients with spontaneous intra-cerebral hemorrhage: Does medication use predict worse outcome?

OBJECTIVES: To assess the impact of anticoagulants and antiplatelet agents on the severity and outcome of spontaneous non-traumatic intra-cerebral hemorrhage (ICH). To evaluate associations between reversal of anticoagulation and mortality/morbidity in these patients. METHODS: Data was collected on a consecutive cohort of adults presenting with ICH to an academic Emergency Department over a 3-year period starting January 2006. RESULTS: The final cohort of 245 patients consisted of 125 females (51.1%). The median age of the cohort was 73 years [inter-quartile (IQR) range of 59-82 years]. Antiplatelet (AP) use was seen in 32.6%, 18.4% were using anticoagulant (AC) and 8.9% patients were on both drugs (AC+AP). Patients on AC had significantly higher INR (median 2.3) and aPTT (median 31 s) when compared to patients not on AP/AC (median INR 1.0, median aPTT 24s; p<0.001). Similarly patients on AC+AP also had higher INR (median 1.9) and aPTT (median 30s) when compared to those not on AC/AP (p<0.001). Hemorrhage volumes were significantly higher for patients on AC alone (median 64.7 cm(3)) when compared to those not on either AC/AP (median 27.2 cm(3); p=0.05). The same was not found for patients using AP (median volume 20.5 cm(3); p=0.813), or both AC+AP (median volume 27.7 cm(3); p=0.619). Patients on AC were 1.43 times higher at risk to have intra-ventricular extension of hemorrhage (IVE) as compared to patients not on AC/AP (95% CI 1.04-1.98; p=0.035). There was no relationship between the use of AC/AP/AC+AP and functional outcome of patients. Patients on AC were 1.74 times more likely to die within 7 days (95% CI 1.0-3.03; p=0.05). No relationship was found between use of AP or AC+AP use and mortality. Of the 82 patients with INR>1.0, 52 patients were given reversal (minimum INR 1.4, median 2.3). Therapy was heterogeneous, with fresh frozen plasma (FFP) being the most commonly used agent (86.5% patients, median dose 4U). Vitamin K, activated factor VIIa and platelets were the other agents used. Post reversal, INR normalized within 24h (median 1.2, IQR 1.1-1.3). There was no association between reversal and volume of hemorrhage, IVE, early mortality (death<7 days) or functional outcome. CONCLUSIONS: Anticoagulated patients were at 1.7 times higher risk of early mortality after ICH. Reversal of INR to normal did not influence mortality or functional outcome.

Factors associated with repeated use of epinephrine for the treatment of anaphylaxis.

BACKGROUND: Studies looking at the use of repeated doses of epinephrine in patients experiencing anaphylaxis are limited. OBJECTIVE: To determine which patients are most likely to receive repeated doses of epinephrine during anaphylaxis management. METHODS: A population-based study with medical record review was conducted. All patients seen during the study period who met the criteria for the diagnosis of anaphylaxis were included. RESULTS: The cohort included 208 patients (55.8% female). Anaphylaxis treatment included epinephrine in 104 patients (50.0%). Repeated doses were used in 27 patients (13.0%), 13 (48.1%) of them female. The median age of those who received repeated doses was 18.9 (interquartile range, 10-34) years vs 31.1 (interquartile range, 15-41) years for those who did not receive repeated doses (P = .06). The inciting agents were food (29.6%), insects (11.1%), medications (22.2%), others (7.4%), and unknown (29.6%). Patients who received repeated doses were more likely to have wheezing (P = .03), cyanosis (P = .001), hypotension and shock (P = .03), stridor and laryngeal edema (P = .007), nausea and emesis (P = .04), arrhythmias (P < .01), and cough (P = .04) and less likely to have urticaria (P = .049). They were more likely to be admitted to the hospital than patients who did not receive repeated doses (48.2% vs 15.6%; P < .001). There was no significant difference in the history of asthma between patients who received repeated doses and those who did not (P = .17). CONCLUSIONS: Of the patients, 13.0% received repeated epinephrine doses. Patients were younger and were likely to present with wheezing, cyanosis, arrhythmias, hypotension and shock, stridor, laryngeal edema, cough, nausea, and emesis and less likely to have urticaria. A history of asthma did not predict use of repeated doses of epinephrine. Our results help identify high-risk patients who may benefit from carrying more than 1 dose of epinephrine.

Visual representation of National Institute of Allergy and Infectious Disease and Food Allergy and Anaphylaxis Network criteria for anaphylaxis.

We present a user-friendly visual representation of The National Institute of Allergy and Infectious Disease and the Food Allergy and Anaphylaxis Network criteria so as to enhance recognition of anaphylaxis and active teaching and learning.

Prescriptions for self-injectable epinephrine and follow-up referral in emergency department patients presenting with anaphylaxis.

BACKGROUND: Anaphylaxis guidelines recommend that patients with a history of anaphylactic reaction should carry self-injectable epinephrine and should be referred to an allergist. OBJECTIVE: To evaluate how frequently patients dismissed from the emergency department after treatment for anaphylaxis received a prescription for self-injectable epinephrine or allergist referral. METHODS: A retrospective medical record review identified patients with anaphylaxis in a community-based study from 1990 through 2000. Records of patients with Hospital Adaptation of the International Classification of Diseases, Second Edition or International Classification of Diseases, Ninth Revision codes representing anaphylaxis were reviewed, and a random sample of patients with associated diagnoses was also reviewed. Patients who met the criteria for diagnosis of anaphylaxis were included in the study. RESULTS: Among 208 patients identified with anaphylaxis, 134 (64.4%) were seen in the emergency department and discharged home. On dismissal, 49 patients (36.6%; 95% confidence interval [CI], 28.4%-44.7%) were prescribed self-injectable epinephrine, and 42 patients (31.3%; 95% CI, 23.5%-39.2%) were referred to an allergist. Treatment with epinephrine in the emergency department (odds ratio, 3.6; 95% CI, 1.6-7.9; P = .001) and insect sting as the inciting allergen (odds ratio, 4.0; 95% CI, 1.6-10.5; P = .004) were significantly associated with receiving a prescription for self-injectable epinephrine. Patient age younger than 18 years was the only factor associated with referral to an allergist (P = .007). CONCLUSIONS: Most patients dismissed after treatment for anaphylaxis did not receive a self-injectable epinephrine prescription or allergist referral. Emergency physicians may be missing an important opportunity to ensure prompt treatment of future anaphylactic reactions and specialized follow-up care.