Ultrasound-guided small vessel cannulation: long-axis approach is equivalent to short-axis in novice sonographers experienced with landmark-based cannulation.

INTRODUCTION: Our primary objective was to describe the time to vessel penetration and difficulty of long-axis and short-axis approaches for ultrasound-guided small vessel penetration in novice sonographers experienced with landmark-based small vessel penetration. METHODS: This was a prospective, observational study of experienced certified emergency nurses attempting ultrasound-guided small vessel cannulation on a vascular access phantom. We conducted a standardized training, practice, and experiment session for each participant. Five long-axis and five short-axis approaches were attempted in alternating sequence. The primary outcome was time to vessel penetration. Secondary outcomes were number of skin penetrations and number of catheter redirections. We compared long-axis and short-axis approaches using multivariable regression adjusting for repeated measures, vessel depth, and vessel caliber. RESULTS: Each of 10 novice sonographers made 10 attempts for a total of 100 attempts. Median time to vessel penetration in the long-axis and short-axis was 11 (95% confidence interval [CI] 7-12) and 10 (95% CI 6-13) seconds, respectively. Skin penetrations and catheter redirections were equivalent and near optimal between approaches. The median caliber of cannulated vessels in the long-axis and short-axis was 4.6 (95% CI 4.1-5.5) and 5.6 (95% CI 5.1-6.2) millimeters, respectively. Both axes had equal success rates of 100% for all 50 attempts. In multivariable regression analysis, long-axis attempts were 32% (95% CI 11%-48%; p=0.009) faster than short-axis attempts. CONCLUSION: Novice sonographers, highly proficient with peripheral IV cannulation, can perform after instruction ultrasound-guided small vessel penetration successfully with similar time to vessel penetration in either the long-axis or short-axis approach on phantom models.

Motor vehicle crash severity estimations by physicians and prehospital personnel.

OBJECTIVE: To determine whether emergency physicians (EPs) and prehospital emergency medical services (EMS) personnel differ in their assessment of motor vehicle crash (MVC) severity and the potential for serious injury when viewing crash scene photographs. METHODS: Attending and resident EPs, paramedics, and emergency medical technicians (EMTs) from a single emergency medicine system used a web-based survey platform to rate the severity of 100 crash photographs on a 10-point Likert scale (Crash Score) and the potential for serious injury on a 0-100% scale (Injury Score). Serious injury was defined as skull fracture or intracranial bleeding, spine fracture or spinal cord injury, intrathoracic or intraabdominal injury, or long bone fracture. Crash and Injury Scores were stratified into EP and paramedic/EMT (EMS) groups and the mean score was calculated for each photo. Spearman rank correlation coefficients with 95% confidence intervals (95% CI) and Bland-Altman plots were constructed to assess agreement. Secondary analyses were performed after categorizing data into quartiles based on participants' estimations of MVC severity. RESULTS: A total of 54 attending and 53 resident EPs, 156 paramedics, and 34 EMTs were invited to participate in the survey. Of these, 39 (72%) attending and 46 (87%) resident EPs, 107 (69%) paramedics, and 17 (50%) EMTs completed the survey. A total of 183 (88%) surveys were completed in full. The overall Crash Score correlation coefficient between EPs and EMS was 0.98 (95% CI, 0.97-0.99). The Crash Score correlation coefficients for each quartile were 0.86 (0.57-0.97), 0.93 (0.85-0.96), 0.58 (0.16-0.85), and 0.88 (0.66-0.97), respectively. The overall Injury Score correlation coefficient between EPs and EMS was 0.98 (0.88-0.97). The Injury Score correlation coefficients for each quartile were 0.94 (0.48-0.91), 0.76 (0.50-0.92), 0.80 (0.69-1.00), and 0.94 (0.57-0.97), respectively. CONCLUSION: Although overall agreement between EPs and EMS personnel was excellent, differences in estimation of crash severity and potential for injury were identified among crashes estimated to be moderate in severity.