Cost-effectiveness of Diagnostic Tools to Establish the Presence of Peripheral Arterial Disease in People With Diabetes.

OBJECTIVE: To evaluate the cost-effectiveness of point-of-care duplex ultrasound (PAD-scan) and other bedside tests for the diagnosis of peripheral arterial disease (PAD) in people with diabetes. BACKGROUND: PAD is a risk factor for cardiovascular disease, diabetic foot ulceration (DFU), and amputation in diabetic patients. Diagnosis enables optimization of therapies to manage these risks. PAD-scan can be performed by frontline staff and has been shown to be the most accurate bedside test. However, its cost-effectiveness has not been investigated. METHODS: A Markov model was constructed to estimate the health outcomes and costs over 5 years of different testing strategies applied to a cohort of diabetic patients. Bedside tests investigated were PAD-scan, ankle-brachial pressure index, toe-brachial pressure index, audible and visual Doppler, transcutaneous pressure of oxygen, and pulse palpation. Health outcomes were incidence of new DFU, major cardiovascular events, amputation, death, and DFU healing rates. Sensitivity analyses were performed. RESULTS: PAD-scan was the most cost-effective bedside test with an incremental cost-effectiveness ratio of £11,391/quality-adjusted life years. PADscan had the highest probability (78.7%) of having the greatest net benefit at a willingness to pay threshold of £20,000 per quality-adjusted life years. It reduced the number of amputations by 24% and the number of cardiovascular deaths by 10% over 5 years, compared to toe-brachial pressure index (next best alternative). PAD-scans superiority in incremental cost-effectiveness ratio occurred at a PAD prevalence threshold of 0.24. DISCUSSION: PAD-scan is a cost-effective test for the detection of PAD in patients with diabetes.

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

BACKGROUND: We aimed to investigate podiatry practice in diagnosing peripheral arterial disease (PAD) in diabetes, decision making once PAD is suspected and limitations of referral pathways. METHODS: A 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. RESULTS: Data 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. CONCLUSION: We have identified important targets for further investigation and quality improvement.

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

BACKGROUND: We 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. METHODS: Twenty 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. RESULTS: Using 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. CONCLUSION: Self-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.

Validation of an assessment tool for pre-operative EVAR planning.

INTRODUCTION: Current methods of teaching endovascular aortic aneurysm repair (EVAR) planning involve non-criteria-based observations that lack validity. The primary aim of this study was to validate an EVAR Planning Objective Structured Assessment of Skill (EpOSAS) tool for the assessment of pre-operative EVAR planning skills. METHODS: Content analysis was performed in order to inform the formulation of EpOSAS domains. Thirty-five participants planned two cases of infra-renal abdominal aortic aneurysm for EVAR, using the OsiriX 7 platform. EVAR planning measurements, with accompanying screenshots, were uploaded onto an electronic data collection sheet. Performance was assessed by three blinded assessors using the EpOSAS tool. Construct and concurrent validity were evaluated. RESULTS: Inter-observer reliability for the three assessors for total EpOSAS scores was high (Cronbach's α 0.89). There were statistically significant differences in total EpOSAS scores between the different experience groups, demonstrating construct validity (Novice (5.3, IQR 5-5.3), Intermediate (15.3, IQR 14.8-16.8) and Experts (17.5, IQR 17-17.7), p<0.001). A statistically significant correlation was found between total EpOSAS scores and percentage error in measurements, demonstrating concurrent validity (Spearman's rank correlation coefficient: R=-0.250, p<0.001). Receiver-operator characteristics analysis established a cut-off point of 16 out of 18 for determining competence. CONCLUSION: We have developed and validated a tool that can be used for the assessment of pre-operative EVAR planning skills.

Validation of a novel venous duplex ultrasound objective structured assessment of technical skills for the assessment of venous reflux.

OBJECTIVES: Duplex ultrasound measurement of reflux time is central to the diagnosis of venous incompetence. We have developed an assessment tool for Duplex measurement of venous reflux for both simulator and patient-based training. METHODS: A novel assessment tool, Venous Duplex Ultrasound Assessment of Technical Skills (V-DUOSATS), was developed. A modified DUOSATS was used for simulator training. Participants of varying skill level were invited to viewed an instructional video and were allowed ample time to familiarize with the Duplex equipment. Attempts made by the participants were recorded and independently assessed by 3 expert assessors and 5 novice assessors using the modified V-DUOSATS. "Global" assessment was also done by expert assessors on a 4-point Likert scale. Content, construct, and concurrent validities as well as reliability were evaluated. RESULTS: Content and construct validity as well as reliability were demonstrated. Receiver operator characteristic analysis-established cut points of 19/22 and 21/30 were most appropriate for simulator and patient-based assessment, respectively. DISCUSSION: We have validated a novel assessment tool for Duplex venous reflux measurement. Further work is required to establish transference validity of simulator training to improve skill in scanning patients. CONCLUSIONS: We have developed and validated V-DUOSATS for simulator training.