Epinephrine auto-injector needle length: what is the ideal length?
OBJECTIVE Given the rarity of contrast reactions in practice, most radiologists have little to no experience in their management, and errors are common. The purpose of this study was to compare treatment of a moderate-severity reaction with intramuscular epinephrine by either the traditional manual method of drawing up and delivering epinephrine with a needle and syringe or the use of an epinephrine autoinjector. SUBJECTS AND METHODS All diagnostic radiologists at the study institution were requested to participate in an annual contrast reaction simulation program, which consisted of three simulation scenarios in a high-fidelity simulation laboratory. During the moderate-severity simulation scenario, the time to administer intramuscular epinephrine and any errors in administration were recorded. Groups were randomized to use an autoinjector device or manual delivery. All participants completed a survey assessing the experience with epinephrine and their comfort in treating contrast reactions using a traditional manual approach versus an epinephrine autoinjector. RESULTS Among 189 participants in the contrast reaction simulation program, 76 participated in a moderate-severity reaction simulation two to five at a time in 25 sessions. Mean total time to administration was significantly longer for manual (108.8 seconds) than for autoinjector (38.7 seconds) delivery (p < 0.001). There were 11 errors in the manual group and one error in the autoinjector group (p = 0.005). Ninety-four percent of participants reported feeling very comfortable or comfortable with the autoinjector as opposed to 60% for manual delivery (p < 0.001). Overall, 96% of participants thought the autoinjector was easier to use. CONCLUSION Use of an epinephrine autoinjector for treatment of contrast reactions was associated with a significantly greater degree of provider comfort, shorter time to administration, and fewer errors.