Pasha Normahani

Variation in duplex peak systolic velocity measurement in a multi-site vascular service

Objective: Duplex US (DUS) is increasingly utilised as a first-line investigation for the assessment of carotid disease. For clinical decision-making, DUS assessment must be accurate and reproducible to ensure reliability. We aimed to investigate the variability in peak systolic velocity (PSV) measurement in a multi-site vascular network. Methods: DUS measurements of PSV were taken from continuous and pulsatile flow, generated by a high fidelity phantom, by 12 experienced vascular scientists across four hospitals. Participants were blinded to the actual PSV value (50 cm/s). Results: We observed an average error of 13.2% (± 8.3) and 11.6% (± 7.5) in PSV measurements taken from pulsatile and continuous waveforms, respectively. Measurements of PSV using the pulsatile waveform demonstrated statistically significant variation across all hospitals; ((hospital/mean) A 43.9 cm/s, B 61.7 cm/s, C 57.4 cm/s, D 47.7 cm/s, p=0.001). Further analysis demonstrated statistically significant variation in 4 instrumentation-related factors when measuring from a pulsatile waveform (Doppler angle, angle of insonation, velocity range, scale range). Conclusion: We observed a significant level of error and variation in PSV measurements across four sites within our vascular network. Variation in instrumentation-related factors may be accountable for this. In light of the centralisation of vascular services, it is increasingly important to unify and implement scanning protocols in order to reduce error and inter-site variability.

The Effect of a Simulation Training Package on Skill Acquisition for Duplex Arterial Stenosis Detection

OBJECTIVES In vascular surgery, duplex ultrasonography is a valuable diagnostic tool in patients with peripheral vascular disease, and there is increasing demand for vascular surgeons to be able to perform duplex scanning. This study evaluates the role of a novel simulation training package on vascular ultrasound (US) skill acquisition. MATERIALS AND METHODS A total of 19 novices measured predefined stenosis in a simulated pulsatile vessel using both peak systolic velocity ratio (PSVR) and diameter reduction (DR) methods before and after a short period of training using a simulated training package. The training package consisted of a simulated pulsatile vessel phantom, a set of instructional videos, duplex ultrasound objective structured assessment of technical skills (DUOSATS) tool, and a portable US scanner. Quantitative metrics (procedure time, percentage error using PSVR and DR methods, DUOSAT scores, and global rating scores) before and after training were compared. RESULTS Subjects spent a median time of 144 mins (IQR: 60-195) training using the simulation package. Subjects exhibited statistically significant improvements when comparing pretraining and posttraining DUOSAT scores (pretraining = 17 [16-19.3] vs posttraining = 30 [27.8-31.8]; p < 0.01), global rating score (pretraining = 1 [1-2] vs posttraining = 4 [3.8-4]; p < 0.01), percentage error using both the DR (pretraining = 12.6% [9-29.6] vs posttraining = 10.3% [8.9-11.1]; p = 0.03) and PSVR (pretraining = 60% [40-60] vs posttraining = 20% [6.7-20]; p < 0.01) methods. CONCLUSION In this study, subjects with no previous practical US experience developed the ability to both acquire and interpret arterial duplex images in a pulsatile simulated phantom following a short period of goal direct training using a simulation training package. A simulation training package may be a valuable tool for integration into a vascular training program. However, further work is needed to explore whether these newly attained skills are translated into clinical assessment.

Randomized study of teaching ultrasound-guided vascular cannulation using a phantom and the freehand versus needle guide-assisted puncture techniques.

The task of ultrasound‐guided vessel cannulation can be technically difficult. Needle guides have been designed to facilitate vessel puncture. We aimed to identify and compare the learning curves of participants performing vessel puncture with conventional freehand (FH) and needle guide–assisted (NG) techniques.

Intensive Simulation Training in Lower Limb Arterial Duplex Scanning Leads to Skills Transfer in Real-World Scenario

OBJECTIVES To train novices to perform an abbreviated duplex lower limb ultrasound scan using simulation training and assess real-world skills transference. METHODS Novices undertook 3 days of simulation training. Their progress was assessed using the Duplex Ultrasound Objective Structured Assessment of Technical Skills (DUOSATS) for simulation and Cumulative Imaging Score (CIS). A final assessment day was held to assess DUOSATS for simulation and real patient scanning, CIS, cumulative diagnostic accuracy, and sections A and B of the Society of Vascular Technology examination. MSc students in vascular ultrasound were also assessed for comparison. RESULTS A total of 17 novices and 7 MSc students with 3-month training participated. Novices improved DUOSATS for simulation scores between days 1, 3, and 4: 18 (17-19) vs 27 (25-28) vs 30 (28-32), (median [interquartile range], p < 0.001). Novices improved in CIS between days 1 and 3: 10 (10-13) vs 21 (19-21), p < 0.001, with a decline on day 4: 15.3 (11.3-18.3), p < 0.001. On the final assessment day, there were no significant differences between novices and MSc students in: DUOSATS for simulation scores (30 [28-32] vs 31 [6-31.5], p = 0.85); DUOSATS for patient assessment (31 [28.7-33.7] vs 26.7 [24.5-35.7], p = 0.41); CIS (15.3 [11.3-18.7] vs 20.7 [12.3-22.2], p = 0.2), respectively. However, novices performed better in section B of the Society of Vascular Technology examination compared with MSc students (72.9% vs 54.3%, p < 0.001). Novices also demonstrated a higher diagnostic accuracy when compared with MSc students (65.7% of arterial segments correctly assessed vs 47.6%, respectively [p = 0.044]). CONCLUSIONS Intensive simulation of 3-day training achieved real patient-based assessments that were comparable to MSc students who were 3 months into their traditional training program.

Self-assessment of surgical ward crisis management using video replay augmented with stress biofeedback

BackgroundWe aimed to explore the feasibility and attitudes towards using video replay augmented with real time stress quantification for the self-assessment of clinical skills during simulated surgical ward crisis management.MethodsTwenty two clinicians participated in 3 different simulated ward based scenarios of deteriorating post-operative patients. Continuous ECG recordings were made for all participants to monitor stress levels using heart rate variability (HRV) indices. Video recordings of simulated scenarios augmented with real time stress biofeedback were replayed to participants. They were then asked to self-assess their performance using an objective assessment tool. Participants attitudes were explored using a post study questionnaire.ResultsUsing HRV stress indices, we demonstrated higher stress levels in novice participants. Self-assessment scores were significantly higher in more experienced participants. Overall, participants felt that video replay and augmented stress biofeedback were useful in self-assessment.ConclusionSelf-assessment using an objective self-assessment tool alongside video replay augmented with stress biofeedback is feasible in a simulated setting and well liked by participants.

Additional file 2: of Self-assessment of surgical ward crisis management using video replay augmented with stress biofeedback

Figure S1. Difference between simulation and resting HRV indices between different experience groups. (PNG 176 kb)

Management of peripheral arterial disease in diabetes: a national survey of podiatry practice in the United Kingdom

BackgroundWe aimed to investigate podiatry practice in diagnosing peripheral arterial disease (PAD) in diabetes, decision making once PAD is suspected and limitations of referral pathways.MethodsA survey, comprising 26 questions was distributed to podiatrists across the UK via mailing lists of collaborating organizations including the College of Podiatry (UK). Response rates were estimated based on NHS workforce data. Analysis of responses from the open-ended questions was performed using inductive content analysis.ResultsData from 283 respondents were analyzed. Response rate for all NHS podiatrists across the UK was estimated to be 6%. For the detection of arterial disease only 18.8% (n = 49/260) of participants reported using a full combination of history, pulse palpation, Doppler and ABPI assessment. Self-reported confidence in detecting arterial disease was highest amongst podiatrists who felt they had received adequate training compared to podiatrists who felt they had not (median 85 (IQR 75–90) vs 67 (50–77), respectively; p < 0.001) as well as those who see > 20 diabetic patients per week compared to those who see < 20 (median 80 (IQR 70–90) vs 72 (60–82.8), respectively; p < 0.001). Over one third of respondents (35.8%, n = 93/260) were aware of missed cases of PAD in the past year and 17.5% (n = 38/217) believed that this resulted in an amputation in some cases.The survey highlighted a lack of clarity amongst podiatrists regarding referral guidelines. Additionally, 69% (n = 169/242) reported that their patients had to wait longer than 2-weeks for specialist vascular assessment and 67.6% (n = 54/80) reported similar waits for a Duplex Ultrasound scan. There was a statistically significant variation in DUS waiting time across the UK (X2 (10, N = 80) = 21.59, p = 0.017). Inability to make a direct referral to vascular services and long delays were reported as major limitations of the referral pathway.ConclusionWe have identified important targets for further investigation and quality improvement.