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.