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 < or = 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.