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BACKGROUND Improving the assessment and training of tracheal intubation is hindered by the lack of a sufficiently validated profile of expertise. Although several studies have examined biomechanics of tracheal intubation, there are significant gaps in the literature. We used 3-dimensional motion capture to study pediatric providers performing simulated tracheal intubation to identify candidate kinematic variables for inclusion in an expert movement profile. METHODS Pediatric anesthesiologists (experienced) and pediatric residents (novices) were recruited from a pediatric institution to perform tracheal intubation on airway mannequins in a motion capture laboratory. Subjects performed 21 trials of tracheal intubation, 3 each of 7 combinations of laryngoscopic visualization (direct or indirect), blade type (straight or curved), and mannequin size (adult or pediatric). We used repeated measures analysis of variance to determine whether various kinematic variables (3-trial average for each participant) were associated with experience. RESULTS Eleven experienced and 15 novice providers performed 567 successful tracheal intubation attempts (9 attempts unsuccessful). For laryngoscopy, experienced providers exhibited shorter path length (total distance traveled by laryngoscope handle; 77.6 ± 26.0 cm versus 113.9 ± 53.7 cm; P = 0.013) and greater angular variability at the left wrist (7.4 degrees versus 5.5 degrees, P = 0.013) and the left elbow (10.1 degrees versus 7.6 degrees, P = 0.03). For intubation, experienced providers exhibited shorter path length of the right hand (mean = 61.1 cm versus 99.9 cm, P < 0.001), lower maximum acceleration of the right hand (0.19 versus 0.14 m/s, P = 0.033), and smaller angular, variability at the right elbow (9.7 degrees versus 7.9 degrees, P = 0.03). CONCLUSIONS Our study and the available literature suggest specific kinematic variables for inclusion in an expert profile for tracheal intubation. Future studies should include a larger sample of practitioners, actual patients, and measures of the cognitive and affective components of expertise.

Background: Carotid to femoral pulse wave velocity (cfPWV), the gold-standard measure of aortic stiffness, is associated with the incidence of cardiovascular disease (CVD) events. Most cfPWV measurements depend on technical proficiency, which limit broader implementation in clinical settings. Recently, an estimated pulse wave velocity (ePWV) measure derived from age and mean arterial pressure (MAP) has been shown to be associated with the risk of CVD events and all-cause mortality and may be a simple alternative to cfPWV. However, ePWV is poorly predictive in non-White individuals, possibly because it was originally developed from European Cohorts. Consequently, our purpose was to: estimate the strength of association between cfPWV and ePWV, and determine whether agreement is consistent across race. Hypothesis: cfPWV and ePWV are in good agreement and association would be consistent across race. Methods: We included Black and White older adults (n= 4,478; 75.2 [5.0] years) from visit 5 (2011-13) of the community-based Atherosclerosis Risk in Communities Study (ARIC). cfPWV was measured using an automated cardiovascular screening device. ePWV was calculated as presented in Fig 1. Association between cfPWV and ePWV was determined using Pearson’s correlation coefficient (r) and Bland-Altman plots. Results: As reported in Fig 1, there was a weak (r=0.35) correlation between cfPWV and ePWV for the total population, with similar correlations when stratified by Blacks (r=0.31) and Whites (r=0.36). Bland-Altman plots indicated significant systematic differences between cfPWV and ePWV (-0.17 m/s, 95% confidence interval: -0.25 to -0.09 m/s, P Conclusion: In older adults, there was weak correlation between cfPWV and ePWV and systematic differences in agreement. Our results do not support ePWV as a surrogate measure of cfPWV in a sample of older White and Black adults.

Article published in Strength and Conditioning Journal on 01 June 2016 (online), available at: https://doi.org/10.1519/SSC.0000000000000229.