Quantitative Approach Based on Wearable Inertial Sensors to Assess and Identify Motion and Errors in Techniques Used during Training of Transfers of Simulated c-Spine-Injured Patients.

Patients with suspected spinal cord injuries undergo numerous transfers throughout treatment and care. Effective c-spine stabilization is crucial to minimize the impacts of the suspected injury. Healthcare professionals are trained to perform those transfers using simulation; however, the feedback on the manoeuvre is subjective. This paper proposes a quantitative approach to measure the efficacy of the c-spine stabilization and provide objective feedback during training. Methods. 3D wearable motion sensors are positioned on a simulated patient to capture the motion of the head and trunk during a training scenario. Spatial and temporal indicators associated with the motion can then be derived from the signals. The approach was developed and tested on data obtained from 21 paramedics performing the log-roll, a transfer technique commonly performed during prehospital and hospital care. Results. In this scenario, 55% of the c-spine motion could be explained by the difficulty of rescuers to maintain head and trunk alignment during the rotation part of the log-roll and their difficulty to initiate specific phases of the motion synchronously. Conclusion. The proposed quantitative approach has the potential to be used for personalized feedback during training sessions and could even be embedded into simulation mannequins to provide an innovative training solution.

Cervical Spine Motion during Transfer and Stabilization Techniques.

Abstract Objectives. To compare paramedics' ability to minimize cervical spine motion during patient transfer onto a vacuum mattress with two stabilization techniques (head squeeze vs. trap squeeze) and two transfer methods (log roll with one assistant (LR2) vs. 3 assistants (LR4)). Methods. We used a crossover design to minimize bias. Each lead paramedic performed 10 LR2 transfers and 10 LR4 transfers. For each of the 10 LR2 and 10 LR4 transfers, the lead paramedic stabilized the cervical spine using the head squeeze technique five times and the trap squeeze technique five times. We randomized the order of the stabilization techniques and LR2/LR4 across lead paramedics to avoid a practice or fatigue effect with repeated trials. We measured relative cervical spine motion between the head and trunk using inertial measurement units placed on the forehead and sternum. Results. On average, total motion was 3.9° less with three assistants compared to one assistant (p = 0.0002), and 2.8° less with the trap squeeze compared to the head squeeze (p = 0.002). There was no interaction between the transfer method and stabilization technique. When examining specific motions in the six directions, the trap squeeze generally produced less lateral flexion and rotation motion but allowed more extension. Examining within paramedic differences, some paramedics were clearly more proficient with the trap squeeze technique and others were clearly more proficient with the head squeeze technique. Conclusion. Paramedics performing a log roll with three assistants created less motion compared to a log roll with only one assistant, and using the trap squeeze stabilization technique resulted in less motion than the head squeeze technique but the clinical relevance of the magnitude remains unclear. However, large individual differences suggest future paramedic training should incorporate both best evidence practice as well as recognition that there may be individual differences between paramedics.

Can a rescuer or simulated patient accurately assess motion during cervical spine stabilization practice sessions?

CONTEXT: Health care providers must be prepared to manage all potential spine injuries as if they are unstable. Therefore, most sport teams devote resources to training for sideline cervical spine (C-spine) emergencies. OBJECTIVE: To determine (1) how accurately rescuers and simulated patients can assess motion during C-spine stabilization practice and (2) whether providing performance feedback to rescuers influences their choice of stabilization technique. DESIGN: Crossover study. SETTING: Training studio. PATIENTS OR OTHER PARTICIPANTS: Athletic trainers, athletic therapists, and physiotherapists experienced at managing suspected C-spine injuries. INTERVENTION(S): Twelve lead rescuers (at the patient's head) performed both the head-squeeze and trap-squeeze C-spine stabilization maneuvers during 4 test scenarios: lift-and-slide and log-roll placement on a spine board and confused patient trying to sit up or rotate the head. MAIN OUTCOME MEASURE(S): Interrater reliability between rescuer and simulated patient quality scores for subjective evaluation of C-spine stabilization during trials (O = best, 10 = worst), correlation between rescuers' quality scores and objective measures of motion with inertial measurement units, and frequency of change in preference for the head-squeeze versus trap-squeeze maneuver. RESULTS: Although the weighted κ value for interrater reliability was acceptable (0.71-0.74), scores varied by 2 points or more between rescuers and simulated patients for approximately 10% to 15% of trials. Rescuers' scores correlated with objective measures, but variability was large: 38% of trials scored as 0 or 1 by the rescuer involved more than 10° of motion in at least 1 direction. Feedback did not affect the preference for the lift-and-slide placement. For the log-roll placement, 6 of 8 participants who preferred the head squeeze at baseline preferred the trap squeeze after feedback. For the confused patient, 5 of 5 participants initially preferred the head squeeze but preferred the trap squeeze after feedback. CONCLUSIONS: Rescuers and simulated patients could not adequately assess performance during C-spine stabilization maneuvers without objective measures. Providing immediate feedback in this context is a promising tool for changing behavior preferences and improving training.

Effectiveness of cervical spine stabilization techniques.

OBJECTIVE: To compare head motions that occur when trained professionals perform the head squeeze (HS) and trap squeeze (TS) C-spine stabilization techniques. DESIGN: Cross-over design. PARTICIPANTS: Twelve experienced lead rescuers. MAIN OUTCOME MEASURES: Peak head motion with respect to initial conditions using inertial measurement units attached to the forehead and trunk of the simulated patient. We compared both HS and TS during lift-and-slide (L&S) and log-roll (LR) placement on spinal board, and agitated patient trying to sit up (AGIT-Sit) or rotate his head (AGIT-Rot). The a priori minimal important difference (MID) was 5 degrees for flexion or extension and 3 degrees for rotation or lateral flexion. RESULTS: The L&S technique was statistically superior to the LR technique. The only differences to exceed the MID were extension and rotation during LR (HS > TS). In the AGIT-Sit test scenario, differences in motion exceeded MID (HS > TS) for flexion, rotation, and lateral flexion. In the AGIT-Rot scenario, differences in motion exceeded MID for rotation only (HS >TS). There was similar intertrial variability of motion for HS and TS during L&S and LR but significantly more variability with HS compared with TS in the agitated patient. CONCLUSIONS: The L&S is preferable to the LR when possible for minimizing unwanted C-spine motion. There is little overall difference between HS and TS in a cooperative patient. When a patient is confused, the HS is much worse than the TS at minimizing C-spine motion.