Bier block (BB), or intravenous regional anesthesia, is a safe and effective alternative to procedural sedation for forearm fracture reduction [1-3]. Using a pneumatic tourniquet, the isolated injured extremity is injected with local anesthetic to provide complete limb analgesia below the tourniquet cuff for painless fracture reduction. The patient remains conscious throughout the procedure, for which, therefore, no preprocedural fasting is required, postprocedure observation period is minimal, and potential risks of procedural sedation are avoided. Intravenous access is required only on the affected limb and only briefly during infusion of local anesthetic. Consequently, this technique is associated with reduced length of stay and resource utilization [4] and can be used for children as young as 2-4 years [1,2,4].

Despite BB’s apparent benefits, it remains infrequently employed for forearm fracture reductions. A survey of 44 North American pediatric emergency departments (PEDs) reported that the most common reason cited for not using local anesthesia techniques was the efficacy of procedural sedation. The authors further suggested that limited physician comfort and perceived longer preparation time were important barriers to BB use [5]. These factors, coupled with sporadic clinical opportunity, departmental logistics, and personnel turnover, are all important challenges to the successful implementation of a sustained BB program.

Recently, our center became the first Canadian PED to successfully introduce a BB program for forearm fracture reductions. PED personnel were trained at the time of BB implementation using a multimodal training course. We observed a sustained increase in BB utilization following training, reaching nearly 40% of all forearm fracture reductions at 2 years. However, course participants reported a modest but significant decrease in comfort with BB at 6 months, and the majority of participants expressed interest in refresher training [6].

Smartphones are widely used and medical smartphone apps have been shown to support the acquisition of technical skills [7]. We have developed a novel point-of-care smartphone app designed to facilitate learning and maintenance of BB competency. Here we report on the app development process and functionality, with an emphasis on both its utility for individuals interested in using BB and its function as a model for the development of an educational tool to support the implementation of any new technique in the emergency department (ED). App dissemination metrics will be tracked, and its utilization at our center will be compared with real-world clinical use of BB for fracture reductions.

The app functions as a self-contained tool to support the utilization of BB by both physicians and nurses and may be used by either novice or experienced users. Additionally, the app contains supporting resources necessary to facilitate the establishment of a departmental BB program. The BB app (Figure 1) contains a brief description of BB and a demonstration video. From the main screen, users can find complete step-by-step instructions. A dose calculator determines weight-based lidocaine dosing, in metric or imperial units with maximal dosages, and a timer directly integrates a stopwatch function. A user-friendly memory aid is provided for the signs, symptoms, and management of lidocaine toxicity. A tab from the main menu links to evidence-based BB references including our institutional protocols for BB and local anesthetic toxicity management, a medication order sheet with integrated dosage calculator, and a safety monitoring record. All reference materials can be saved, printed, or emailed from within the app directly. All content was adapted from our evidence-based institutional BB training course [6].

Feedback was collected from departmental stakeholders following BB training to determine preferences for app content and features. The app was piloted for technical ease of use and clarity, and ongoing quality feedback was incorporated into subsequent app updates. All content and protocols received institutional approval for release from the McGill University Health Centre.

Beta testing was performed using Apple’s proprietary TestfFight software (Apple Inc). Total app storage requirement is 30 MB, and once installed on a mobile device, all content is available without internet connection. The current version is compatible with Apple iOS devices and is available for free through the Apple App Store. Development costs were under Can $1250 in addition to a mandatory fixed recurring cost of Can $100 per year to maintain an Apple developer account.

App dissemination will be tracked using the analytics provided by the app builder and the Apple App Store Analytics software, as described elsewhere [8]. Metrics tracked will include Web-based app views, referrals, user engagement (number of sessions and active devices), total downloads, and retention. Users will be invited via the app to participate in a self-administered electronic survey to assess self-reported perceptions of the BB app. User-perspective surveys will be developed and reported according to published guidelines [9]. Specific data on app utilization and timing of use will be tracked among users in our PED in parallel to real-world clinical use of BB for pediatric fracture reductions [6]. Tracking of app usage in our PED will make use of the external tester function of Apple TestFlight software.