Impact of a Point-of Care Ultrasound Examination on the Management of Acute Respiratory or Circulatory Failure Patients in the Emergency Department: The Impulse Before-and-After Implementation Study

Abstract

Background: Despite its diagnostic accuracy, the clinical impact of the use of Point-of-care Ultrasound (POCUS) in the emergency department (ED) is not well described, especially when performed by junior in-training residents. Aim of the study: To assess the effect of a short, structured POCUS training program on the management of ED patients by in-training residents. Method: IMPULSE is a before-and-after implementation study, evaluating the impact of a structured POCUS training program for ED in-training residents on the management of patients admitted for acute respiratory and/or circulatory failure in a Swiss regional hospital. The training curriculum was organized in three stages and combined an on-line training course, an 8-hour practical hands-on session, and 10 supervised POCUS exams. The ED residents who successfully completed the curriculum participated in the study. Observed outcomes were time to ED diagnosis, rate of correct diagnosis made during the ED stay and time needed to reach it, time to prescribe an appropriate treatment, and hospital mortality. Standard statistical analyses were performed with the use of Chi-square and Mann-Whitney U tests as appropriate, completed by a Bayesian analysis, with a Bayes Factor (BF) >3 considered as significant. Results: Sixty-nine patients were included before the training program implementation and 54 after. After implementation, the median time to ED diagnosis was 25 minutes (IQR 44) vs 30 minutes (IQR 56) before implementation, a difference that was significant (BF 9.6). The rate of correct diagnosis was higher (95 vs 52%) (p<0.001) and the time to make this correct diagnosis was significantly shorter after implementation (25 minutes, IQR 45, vs 43, IQR 60) (BF 5.0). This had an impact on the median time to prescribe the appropriate therapy, with a trend toward a shorter delay (47 minutes, IQR 76, vs 70, IQR 100) (BF 2.0). Eventually, there was a significant difference in hospital mortality (13% vs 5.5%, BF 15.7). Conclusion: The IMPULSE study shows that the implementation of a short, structured POCUS training program for ED residents to use ultrasound for the initial evaluation of acute respiratory and circulatory failure patients has an impact on diagnostic accuracy, on time to make a correct diagnosis and to prescribe an appropriate therapy, and eventually possibly on hospital mortality. If these results are reproduced in other settings, POCUS use by ED residents after short, structured training curriculum could become the standard of care for these patients.