Epinephrine in anaphylaxis: higher risk of cardiovascular complications and overdose after administration of intravenous bolus epinephrine compared with intramuscular epinephrine.

BACKGROUND: Epinephrine is the drug of choice for the management of anaphylaxis, and fatal anaphylaxis is associated with delayed epinephrine administration. Data on adverse cardiovascular (CV) complications and epinephrine overdose are limited. OBJECTIVE: To compare rates of CV adverse events and epinephrine overdoses associated with anaphylaxis management between various routes of epinephrine administration among patients with anaphylaxis in the emergency department. METHODS: This was an observational cohort study from April 2008 to July 2012. Patients in the emergency department who met diagnostic criteria for anaphylaxis were included. We collected demographics; route of epinephrine administration; trigger; overdose; and adverse CV events, including arrhythmia, cardiac ischemia, stroke, angina, and hypertension. RESULTS: The study cohort included 573 patients, of whom, 301 (57.6%) received at least 1 dose of epinephrine. A total of 362 doses of epinephrine were administered to 301 patients: 67.7% intramuscular (IM) autoinjector, 19.6% IM injection, 8.3% subcutaneous injection, 3.3% intravenous (IV) bolus, and 1.1% IV continuous infusion. There were 8 CV adverse events and 4 overdoses with 8 different patients. All the overdoses occurred when epinephrine was administered IV bolus. Adverse CV events were associated with 3 of 30 doses of IV bolus epinephrine compared with 4 of 316 doses of IM epinephrine (10% vs 1.3%; odds ratio 8.7 [95% CI, 1.8-40.7], P = .006). Similarly, overdose occurred with 4 of 30 doses of IV bolus epinephrine compared with 0 of 316 doses of IM epinephrine (13.3% vs 0%; odds ratio 61.3 [95% CI, 7.5 to infinity], P < .001). CONCLUSION: The risk of overdose and adverse CV events is significantly higher with IV bolus epinephrine administration. Analysis of the data supports the safety of IM epinephrine and a need for extreme caution and further education about IV bolus epinephrine in anaphylaxis.

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.

Pure tubular carcinoma and axillary nodal metastases.

BACKGROUND: Pure tubular carcinoma of the breast is a rare subtype with a low incidence of axillary lymph node metastases. The aim of this study was to determine the frequency of axillary lymph node metastasis in patients with pure tubular carcinoma. METHODS: We identified patients diagnosed with tubular carcinoma from 1987 to 2009 from our institution's tumor registry. Pathology slides were reviewed, and pure tubular carcinoma was defined as ≥ 90% tubule formation, low nuclear grade, and rare to no mitoses. Medical records were reviewed for clinicopathologic data including tumor size, number of positive and negative axillary lymph nodes, treatment, and recurrence. RESULTS: We identified 105 cases of pure tubular carcinoma of the breast in 103 patients. Median tumor size was 0.8 (range 0.1-1.8) cm. Nodal staging was performed in 93 cases (89%). Five patients (5.4%) had positive lymph nodes, and two patients (2.2%) had isolated tumor cells. All patients with lymph node metastases had tumors >0.8 cm in size. At 5.2 years' follow-up, no patients have developed recurrence or metastases, or have died from breast cancer. CONCLUSIONS: Axillary lymph node metastases are not common in small pure tubular carcinomas. Nodal staging may be omitted in small pure tubular carcinomas.