Patient Ability to Use Old versus New/Modified Model Adrenaline Autoinjection Emergency Medical Devices for Anaphylaxis in Prehospital Setting: A Systematic Review and Meta-Analysis

Background: The goal of this study was to determine the individual’s ability to use new/modified model AAI compared to old model AAIs devices for anaphylaxis. Methods: The protocol was established a priori and published on PROSPERO (CRD42021229691) and was conducted based on PRISMA guidelines. MEDLINE and CENTRAL were searched until 31 January 2021. Only RCTs were included in this review. Primary studies comparing old model AAI to new/modified model AAI emergency medical devices were included. Primary outcomes included number of successful administrations, and number of individuals to complete all steps. Secondary outcomes included successful removal of device safety guards, placement of correct end of the device against the thigh and holding of the device in place for adequate time after administration; the frequency of an adverse event (digital injection); individual preferences in terms of size, individual preference in terms of ease for carrying, overall patient preference; and the mean time of delivery. Results: Overall, seven trials consisting of 1359 patients were analyzed. Reporting of adverse events was limited to digital injection, which was significantly higher in the old model AAI (RR 6.90, 95% CI 3.27 to 14.57; I2 statistic = 0%; p p = 0.16; seven trials, 2196 participants; low quality evidence). Conclusions: We cannot make any new recommendations on the effectiveness of different models of AAIs regarding successful administration. However, considering the aspect of safety, we think that mew/modified model AAI can be chosen as the old model AAI was associated with a higher frequency of the adverse event (digital injection)