Determining an effective route of administration for epinephrine: What is the evidence?
Many adult patients with cancer receive medications that have the potential to cause severe hypersensitivity reactions. Immediate management of a hypersensitivity reaction is critical to a successful patient outcome; however, variations in practice led the Oncology Advanced Practice Nursing Group at The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins in Baltimore, Maryland, to question which route of administration of epinephrine is most effective in treating these reactions, according to a presentation during the Oncology Nursing Society 36th Annual Congress.
An evidence-based practice team initially identified 26 different hospital protocols and order-sets containing epinephrine with various routes of administration, including intravenous (39%), subcutaneous (SQ; 23%), intramuscular or intravenous (8%), or no route specified (30%), said Marie E. Swisher, MSN, RN, OCN®.
A comprehensive literature review using the MeSH terms “epinephrine,” “hypersensitivity,” “anaphylaxis,” “injections,” and “injections (intramuscular)” (IM) resulted in 309 articles; those that described use in children were excluded. The evaluation process included two commercial Web sites (EpiPen and Twininject) and four medical reference sites (eg, MDconsult). The 34 articles selected were published from 1997 to 2010.
The articles were reviewed utilizing the Johns Hopkins Nursing evidence-based practice model, an 18-step process that begins with a practice question, determines evidence, and then translates those findings. Of the articles identified, 38% recommended IM/autoinjector device, 32% IM, 12%, SQ/IM routes of administration, 5% autoinjector device alone and 3% IM/IV. In addition, 3% did not specify a route of injection
Articles including auto-injectors primarily focused on populations receiving epinephrine in the outpatient setting. Twenty-six sources cited one experimental epinephrine study (13 healthy males) published in 2001 to support the IM route. In this study, Simons and colleagues concluded that the auto-injector (EpiPen) was equal to IM injection and superior to SQ.1
However, this research cannot necessarily be generalized to the female population, Swisher said, because EpiPen needles are shorter than traditional SQ needles. A study that specifically examined this issue concluded distance from skin to muscle is higher in women than in men; therefore, the EpiPen may not deliver IM in some women.2 A comparison of needle lengths found IM injection length ranged from one-half inch to 2 inches; SQ injection length was five-eighths of an inch; and autoinjector length was manufacturer dependent and ranged from one-half inch to nine-sixteenths of an inch.
The IM route cannot currently be considered superior to the SQ route, as there are no known studies focusing on IM versus SQ (auto-injector) injection in women, Swisher noted. A limited body of research evidence supports IM only as the most effective route to administer epinephrine. No known studies have demonstrated inferior results using SQ epinephrine. Finally, a large body of anecdotal evidence supports SQ or IM routes for epinephrine dose delivery.Swisher noted that since completion of the project, the hospital has introduced computerized provider order entry and has standardized epinephrine dosing for management of hypersensitivity/anaphylaxis using the SQ route, Swisher concluded, adding that this is consistent with the findings of the project. Additional research should be conducted to determine the epinephrine administration technique that results in the most favorable patient outcomes.