title: Effect of a point-of-care ultrasound protocol on the diagnostic performance of medical learners during simulated cardiorespiratory scenarios.
abstract: BACKGROUND
  Goal-directed point-of-care ultrasound (PoCUS) protocols have been shown to improve the diagnostic accuracy of the initial clinical assessment of the critically ill patient. The diagnostic impact of the Abdominal and Cardiac Evaluation with Sonography in Shock (ACES) protocol was assessed in simulated emergency medical scenarios.
  
  
  METHODS
  Following a focused PoCUS training program, the diagnostic accuracy, confidence, and precision of 12 medical learners participating in standardized scenarios were tested using high-fidelity clinical and ultrasound simulators. Participants were assessed during 72 simulated cardiorespiratory scenarios. Differential diagnoses were collected from participants before and after PoCUS in each scenario, and confidence surveys were completed. Data were analysed using R software.
  
  
  RESULTS
  Prior to PoCUS, 45 (62.5%) correct primary diagnoses were made compared with 64 (88.9%) following PoCUS (χ2=14, 1df, p=0.0002). PoCUS was also shown to increase participants' confidence in their diagnoses. The mean confidence in diagnosis score pre-PoCUS was 52.2 (SD=14.7), whereas post-PoCUS it was 81.7 (SD=9.5). The estimated difference in means (-28.36) was significant (t=-7.71, p<0.0001). Using PoCUS, participants were further able to narrow their differential diagnoses. The median number of diagnoses for each patient pre-PoCUS was 3.5 (interquartile range [IQR]=3.8, 3.0) with a median of 2.3 (IQR=2.9,1.5) diagnoses post-PoCUS. The difference was significant (W=0, p<0.001).
  
  
  CONCLUSIONS
  This pilot study suggests that, in medical learners newly competent in PoCUS, the addition of an ACES PoCUS protocol to standard clinical assessment improves diagnostic accuracy, confidence, and precision in simulated cardiorespiratory scenarios. This is consistent with clinical studies and supports the use of ultrasound during medical simulation.
authors.affiliation: *Dalhousie Medicine New Brunswick,Saint John,NB.
authors.forename: Adam R
authors.initials: AR
authors.lastname: Parks
authors.affiliation: *Dalhousie Medicine New Brunswick,Saint John,NB.
authors.forename: Glenn
authors.initials: G
authors.lastname: Verheul
authors.affiliation: ‡Research Services,Saint John Regional Hospital,NB.
authors.forename: Denise
authors.initials: D
authors.lastname: LeBlanc-Duchin
authors.affiliation: *Dalhousie Medicine New Brunswick,Saint John,NB.
authors.forename: Paul
authors.initials: P
authors.lastname: Atkinson
mesh_terms: D016887:Cardiopulmonary Resuscitation / Q000193:education*; D004501:Education, Medical / Q000379:methods*; D004521:Educational Measurement / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D010865:Pilot Projects; D019095:Point-of-Care Systems; D013337:Students, Medical / Q000523:psychology*
keywords: emergency medicine; medical education; simulation; ultrasound