The Effect of Lower Limb Revascularization on Flow, Perfusion, and Systemic Endothelial Function: A Systematic Review.

Peripheral arterial disease (PAD) is associated with reduced lower limb blood flow and tissue perfusion. The consequent reduction in vessel wall shear stress as well as ischemia-reperfusion injury has also been associated with systemic endothelial dysfunction and inflammation. We aimed to explore the impact of lower limb revascularization on (1) lower limb blood flow, (2) tissue perfusion, and (3) systemic endothelial function. We performed a systematic literature search using the MEDLINE, Embase, and Web of Science databases. Eligible studies measured changes in lower limb blood flow, perfusion, or systemic endothelial function following revascularization for the treatment of symptomatic PAD. We found 19 eligible studies, which were limited by considerable heterogeneity. Current evidence suggests that revascularization has a positive effect on flow, perfusion, and systemic endothelial dysfunction. Any changes may take a number of weeks to become apparent. There is a need for well-designed studies to explore the association between flow, perfusion, and endothelial dysfunction.

A novel team Familiarity Score for operating teams is a predictor of length of a procedure: A retrospective Bayesian analysis.

OBJECTIVE: The aim of our retrospective study was to assess whether a novel team Familiarity Score (FS) is associated with the length of procedure (LOP), postoperative length of stay (LOS), and complication rate after vascular procedures. METHODS: We retrospectively analyzed 326 vascular procedures performed at a tertiary care vascular surgery center between April 2012 and September 2014. Data collected included patients' age, American Society of Anesthesiologists grade, LOP, type and urgency of procedure, LOS, and complications. Familiarity Score (FS) was defined as the sum of the number of times that each possible pair of the team (vascular consultant, vascular registrar, scrub nurse, anesthetic consultant) within the team had worked together during the previous 6 months, divided by the number of possible combinations of pairs in the team. Bayesian statistics was used to analyze the data. RESULTS: FS was significantly associated with type and urgency of the procedure (Bayes factor [BF] >1000). Emergency procedures were performed by less familiar teams, and the least familiar teams were involved in the emergency aortic procedures-endovascular and open. FS was strongly associated with LOP (BF = 37) but not with LOS (BF = 4.0) and complication rate. CONCLUSIONS: FS in vascular teams was shown to be strongly associated with LOP, suggesting that more familiar teams might collaborate more efficiently.

A pilot study of preoperative heart rate variability predicting pain during local anesthetic varicose vein surgery.

OBJECTIVE: Local anesthetic endovenous procedures were shown to reduce recovery time, to decrease postoperative pain, and to more quickly return the patient to baseline activities. However, a substantial number of patients experience pain during these procedures. The autonomic nervous system modulates pain perception, and its influence on stress response can be noninvasively quantified using heart rate variability (HRV) indices. The aim of our study was to evaluate whether preoperative baseline HRV can predict intraoperative pain during local anesthetic varicose vein surgery. METHODS: Patients scheduled for radiofrequency ablation were included in the study. They had their electrocardiograms recorded from a single channel of a custom-made amplifier. Each patient preoperatively filled in forms Y-1 and Y-2 of Spielberger's State and Trait Anxiety Inventory, completed the Aberdeen Varicose Vein Questionnaire, and rated anxiety level on a numeric scale. Postoperatively, patients filled in the pain they felt during the procedure on the numeric pain intensity scale. MATLAB software (MathWorks, Natick, Mass) was used to extract R waves and to generate HRV signals, and a mathematical model was created to predict the pain score for each patient. RESULTS: In multivariable analysis, we looked into correlation between reported patient's pain score (rPPS) and Aberdeen Varicose Vein Questionnaire score, preoperative forms Y-1 and Y-2, preoperative anxiety level, and predicted patient's pain (pPPS) score. Multivariable analysis found association only between rPPS and pPPS. The pPPS was significantly correlated with rPPS (R = 0.807; P < .001) with accuracy of prediction of 65.2%, which was calculated from R2 on a linear regression model. CONCLUSIONS: This preliminary study shows that preoperative HRV can accurately predict patients' pain, allowing patients with higher predicted score to have the procedure under general anesthesia.

Chronic venous insufficiency: a new concept to understand pathophysiology at the microvascular level - a pilot study.

OBJECTIVES: The real mechanism for the development of the later stages of chronic venous insufficiency still remains unclear. Venous hypervolemia and microvascular ischemia have been reported to be the consequences of venous insufficiency. The aim of this study was to investigate the effects of induced venous hypovolemia by dorsiflexion exercise in patients with venous leg ulcers. METHODS: Thirty-six participants, all of whom had an ankle brachial pressure index between 0.8 and 1.2 mmHg, were chosen for this study. The participants were divided into two groups: Group A, a non-exercise group and Group B which performed regular exercise in the form of dorsiflexion. The basic assessment, including the history and examination, ankle-brachial pressure index (ABPI), Duplex scan and tcPO2 measurements, was performed on two occasions at the beginning of the trial and after three months. RESULTS: The tcPO2 level was low in the beginning in all the subjects, but the picture was different at the end of the trial. There was a significant increase in the tcPO2 level (p<0.001) in the patients who performed exercise while there was no difference in the measurements (p>0.05) in the non-exercise group. CONCLUSIONS: Induced venous hypovolemia through regular evacuation of the peripheral venous system improved tissue oxygenation at skin level. Venous hypervolemia may be the main contributing factor for the development of venous hypoxia and microvascular ischemia.

Effectiveness of a multicenter training programme to teach point-of-care vascular ultrasound for the detection of peripheral arterial disease in people with diabetes.

BACKGROUND: The primary aim of this study was to evaluate the effectiveness of a training programme to teach a focused bedside ultrasound scan (PAD-scan; Podiatry Ankle Duplex Scan) for the detection of arterial disease in people with diabetes. METHODS: Five podiatrists and one diabetologist across two hospitals were enrolled in a structured training programme consisting of a training course (1-day), supervised scanning (5-weeks), independent scanning (3-weeks) and a final evaluation of performance (1-day).Time, technical skills (Duplex Ultrasound Objective Structured Assessment of Technical Skills tool (DUOSATS); minimum score = 6, maximum score = 26) and accuracy (level of agreement with vascular scientist PAD-scan assessment) were assessed for every supervised scan and again for the final evaluation of performance. RESULTS: A total of 90 PAD-scans in 65 patients were performed during the supervised phase. Participants demonstrated significant improvements in median time (19 min(IQR 13.9-25.5) vs 9.3 min (IQR 7.3-10.5);p = 0.028) and DUOSATS scores (17.5 (IQR 16.8-21) vs 25 (IQR 24-25.3); p = 0.027). At the final evaluation, participants completed scans in 5.4 min (IQR 5.3-5.9), achieved full DUOSAT scores and perfect agreement with the vascular scientist. CONCLUSION: A structured training programme, integrated into diabetic foot clinics, was effective in teaching the PAD-scan.

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.

An investigation of skin perfusion in venous leg ulcer after exercise.

INTRODUCTION: A venous leg ulcer (VLU) has a major impact on the quality of life and functional ability of individuals, but no single treatment is yet effective. This study investigates the changes induced by dorsiflexion exercise on skin perfusion in VLU patients to achieve a better understanding of venous ulcer pathophysiology. METHODS: Seventy-eight venous leg ulcer patients were randomised into four groups. The non-exercise groups included a control group (n = 18) and a compression therapy group (n = 20) and the exercise groups included an exercise-only group (n = 20) and a compression and exercise group (n = 20). The exercise groups were expected to perform exercise for three months. Measurements included transcutaneous oximetry (tcPO2) and laser Doppler flowmetry (LDF). Skin perfusion measurements for all groups were taken twice: at the beginning and end of the three-month period. RESULTS: Initially, all participants showed a low level of tcPO2. The exercise groups showed a significant increase after three months of exercise (p<0.001), the tcPO2 level remained the same in the non-exercise groups. The LDF parameters decreased significantly (p<0.001) in the compression and exercise group and decreased to a lesser extent in the exercise-only group. There were no LDF changes in the non-exercise groups. CONCLUSIONS: Perfusion measurements showed significant changes after three months of regular exercise. We conclude that exercise has a significant effect on tissue perfusion parameters in venous leg ulcer and this effect may play a role in understanding the pathophysiology of VLU.

Podiatry Ankle Duplex Scan: Readily Learned and Accurate in Diabetes.

We aimed to train podiatrists to perform a focused duplex ultrasound scan (DUS) of the tibial vessels at the ankle in diabetic patients; podiatry ankle (PodAnk) duplex scan. Thirteen podiatrists underwent an intensive 3-hour long simulation training session. Participants were then assessed performing bilateral PodAnk duplex scans of 3 diabetic patients with peripheral arterial disease. Participants were assessed using the duplex ultrasound objective structured assessment of technical skills (DUOSATS) tool and an "Imaging Score". A total of 156 vessel assessments were performed. All patients had abnormal waveforms with a loss of triphasic flow. Loss of triphasic flow was accurately detected in 145 (92.9%) vessels; the correct waveform was identified in 139 (89.1%) cases. Participants achieved excellent DUOSATS scores (median 24 [interquartile range: 23-25], max attainable score of 26) as well as "Imaging Scores" (8 [8-8], max attainable score of 8) indicating proficiency in technical skills. The mean time taken for each bilateral ankle assessment was 20.4 minutes (standard deviation ±6.7). We have demonstrated that a focused DUS for the purpose of vascular assessment of the diabetic foot is readily learned using intensive simulation training.

Sources of Delay in the Acute Limb Ischemia Patient Pathway.

BACKGROUND: Acute limb ischemia (ALI) continues to pose a significant challenge to clinicians and is associated with an unacceptably high rate of morbidity and mortality. Despite its time critical nature, little is known regarding the delays encountered during the patient pathway. The aim of this study was to identify sources of delay in the patient pathway at our institution. METHODS: Sixty-seven cases of ALI of the lower extremities from 66 patients, who had presented to our center between May 2003 and April 2014, were identified for retrospective analysis. Data were retrieved from the patient records, discharge summaries and hospital laboratory, emergency department and radiology databases. RESULTS: Median time from onset of symptom to arrival at our institution was 11.35 hr (interquartile range [IQR] 6.27-72). Median cumulative time taken from arrival to vascular team review was 40 min (22.5-120), to imaging being performed was 4.75 hr (2.42-17.25), and to intervention being performed was 10.2 hr (4-31). There were significantly longer delays to presentation in those transferred from inpatient beds as compared with those transferred from the emergency department of other hospitals (66 hr [10.3-98] vs. 8 hr [5.6-14.9], P = 0.007). In total, 84.6% of patients underwent preoperative arterial imaging. Time taken from arrival to diagnostic arterial imaging was significantly longer in patients presenting out-of-ours (15 hr [6.5-20.75]) as compared with patients presenting in-hours (3.5 hr [2-6.5], P = 0.014) or during the weekend (2 hr [2-3], P = 0.022). Time from presentation to intervention was significantly shorter in patients presenting over the weekend (3.9 hr [2.6-5.1]) as compared with those presenting in-hours (14.2 hr [6.2-29], P = 0.006) and out-of-hours (16 hr [10-33], P = 0.021). Out-of-hours, a significant portion of the delay, was attributable to imaging (median time to imaging 15 hr). CONCLUSIONS: This study demonstrates the systematic nature of delays in the patient pathway from onset of symptoms to treatment. Several factors including time to patient presentation and time to imaging and delays in timely transfer to an appropriate facility contribute to this. Strategies need to be deployed to reduce time to revascularization.

The impact of a focused vascular lower limb arterial duplex (F-VLAD) scan in management decisions for acute limb ischaemia.

OBJECTIVE: To establish the diagnostic accuracy of a 'focused vascular lower limb arterial duplex scan (F-VLAD)' developed to facilitate rapid decision-making for acute limb ischaemia (ALI). METHODS: Ten cases of ALI were identified from our patient database; clinical details, history and examination findings were extracted from the clinical notes. Original 'full' duplex ultrasound (DUS) pictorial reports were 're-formatted' to include only anatomical segments included in the 'F-VLAD' scan. The series of 10 reports were emailed to 1741 vascular surgeons. Each recipient received a random mixture of full and F-VLAD scans. Participants were asked regarding next step in management and confidence in decision-making (Likert scale; 1 strongly disagree, 5 strongly agree). The cases were again sent out to the same database and respondents were asked as to the cause of ischaemia (embolic or thrombosis). RESULTS: Eighty-one participants responded to the first survey and 43 participants to the second survey. Participants felt more confident making decisions regarding management using the full duplex report compared to the F-VLAD report (4 (3-4) vs 3 (2-4), median (IQR); p<0.001). However, there was no significant difference in diagnostic accuracy (differentiating embolus from thrombosis) when comparing the F-VLAD and full DUS reports (85.4% vs 88.3%; p=0.461). F-VLAD and 'full' DUS reports had comparable sensitivity (85.1% vs 86.8%), specificity (85.6% vs 89.2%),positive predictive value (PPV) (80.4% vs 81.9%) and negative predictive value (NPV) (89.2% vs 92.2%), respectively. CONCLUSION: The F-VLAD scan has comparable accuracy to a traditional full DUS in diagnosing the underlying aetiology of ALI. This may facilitate surgeon-performed point-of-care DUS.

A systematic review and meta-analysis of the risk for development of varicose veins in women with a history of pregnancy.

OBJECTIVE: The association between pregnancy and the development of varicose veins is uncertain. We aimed to determine whether a history of pregnancy is associated with the development of varicose veins. METHODS: We performed a systematic literature search using the databases of PubMed, Embase, Robert Koch-Institut, and Cochrane Central and the references of included papers. Eligible studies were all epidemiologic observational studies in which the outcome "varicose veins" and pregnancy history were assessed. The quality of each study was evaluated on the basis of the Dutch Cochrane review checklist and by the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement. For our meta-analysis, a random effects model was applied to pool odds ratios and 95% confidence intervals across studies. RESULTS: We found nine eligible studies enrolling 17,109 women. Pregnancy was associated with a significant risk increase in developing varicose veins. The results of our meta-analysis suggest that the odds for women with a history of pregnancy in developing varicose veins significantly increases by 82% (odds ratio, 1.82; 95% CI, 1.43-2.33) compared with women with no history of pregnancy. As expected for epidemiologic observational studies, the heterogeneity was considerably high (I(2) = 81%). CONCLUSIONS: Our meta-analysis strongly supports the hypothesis that there is a significant and strong association between a history of pregnancy and varicose veins. However, qualitative and quantitative differences among studies were evident and were also reflected in a considerably high heterogeneity.

Potential identification of a claudicant group vulnerable to acute kidney injury.

This observational study aimed to investigate the relationship between renal injury, endothelial function and oxidative stress in claudicants undergoing maximal treadmill exercise. Twenty patients with claudication were identified in whom the urinary N-acetyl-ß-D-glucosaminidase (ß-NAG)/creatinine ratio, plasma oxidative state and endothelial function were tested pre- and post-maximal treadmill walking exercise. Of the 20 participants in this study, the urinary NAG/creatinine (Cr) rose from a pre-exercise level of 8.9, 6.7 to 14.3 (µmol/L/mmol Cr; median, IQR) to 12.9, 9.1 to 17.7 post exercise (p = 0.0003, Mann Whitney U test). Of the 20 participants, eight participants had a rise of the NAG/Cr ratio post exercise whereas 12 did not. Participants with a rise in the NAG/Cr ratio post exercise had a greater ability to increase endothelial reactivity (%; median, IQR; 2.56, 0.1 to 3.7) cf. (0.1, -4.8 to 0.9, p = 0.03); they also walked further (metres; median, IQR; 415, 208 to 908) cf. (170, 100 to 315, p = 0.04), had a lower pre-exercise H2O2 (median, IQR; 1.9, 1.4 to 2.3 cf. 2.7, 2.1 to 3.3; p = 0.04) and a greater rise in H2O2 post exercise (18.8, -1.5 to 129.7 cf., -7.7, -13.9 to -2.0, p = 0.04). The mechanism by which the phenotypically distinct sub-group of patients with intermittent claudication who experience a NAG/Cr rise involves complex interactions between systemic oxidative stress and endothelial function. Implications on cardiovascular risk in this group requires further investigation.

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.

Pre-operative methods to predict need for shunting during carotid endarterectomy.

OBJECTIVES: To establish whether pre-operative investigations are able to predict cerebral tolerance to carotid cross clamping during carotid endarterectomy (CEA). METHODS: A search of the MEDLINE database from 1950 to 2015 was made in combination with manual cross-referencing using the search strategy: ("carotid" [all fields] AND "endarterectomy" [all fields]) AND "preoperative" [all fields]) AND "clamping" [all fields]) AND ("MRA" [all fields] OR "MRI" [all fields] OR "CT" [all fields] OR "CTA" [all fields] OR "EEG" [all fields] OR "Doppler" [all fields] OR "angiography" [all fields]). A total of 20 studies were identified as eligible for inclusion. RESULTS: 3D Time of Flight MRA and acetazolomide stress SPECT imaging have been reported to have a negative predictive value of 96% and 94% respectively for the need for intraoperative shunting during carotid endarterectomy. CONCLUSIONS: There is some evidence to suggest that pre-operative imaging investigations can reliably identify which patients undergoing CEA will not require carotid shunting for neurological protection. However, this evidence is limited and there is a need for more rigorous studies to be conducted.

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.

Training safer surgeons: How do patients view the role of simulation in orthopaedic training?

BACKGROUND: Simulation allows training without posing risk to patient safety. It has developed in response to the demand for patient safety and the reduced training times for surgeons. Whilst there is an increasing role of simulation in orthopaedic training, the perception of patients and the general public of this novel method is yet unknown. Patients and the public were given the opportunity to perform a diagnostic knee arthroscopy on a virtual reality ARTHRO Mentor simulator. After their practice session, participants answered a validated questionnaire based on a 5-point Likert Scale assessing their opinions on arthroscopic simulation. Primary objective was observing perception of patients on orthopaedic virtual reality simulation. FINDINGS: There were a total of 159 respondents, of which 86% were of the opinion that simulators are widely used in surgical training and 94% felt that they should be compulsory. 91% would feel safer having an operation by a surgeon trained on simulators, 87% desired their surgeon to be trained on simulators and 72% believed that additional simulator training resulted in better surgeons. Moreover, none of the respondents would want their operation to be performed by a surgeon who had not trained on a simulator. Cronbach's alpha was 0.969. CONCLUSIONS: There is also a clear public consensus for this method of training to be more widely utilised and it would enhance public perception of safer training of orthopaedic surgeons. This study of public perception provides a mandate to increase investment and infrastructure in orthopaedic simulation as part of promoting clinical governance.

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

PURPOSE: 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. METHODS: Thirty-six participants were randomly allocated to either the FH or the NG group. They were asked to consecutively perform as many as 30 vessel punctures on a simulated phantom model. Quantitative metrics (time taken and number of skin and posterior-wall punctures) were recorded and compared between the two groups. The cumulative sum and moving F-test statistical methods were used to delineate the learning curves. RESULTS: There was a significantly lower rate of posterior-wall punctures in the NG group than in the FH group (15% versus 26%; p < 0.0001). Participants in the NG group also performed significantly fewer skin punctures than did those in the FH group (mean, 405 versus 515; p < 0.0001). Cumulative sum statistical method analysis showed that participants in the NG group surmounted the learning curve earlier (13 attempts; interquartile range, 10.3-17.0) than did those in the FH group (19 attempts; interquartile range, 15.0-27.5). The number of attempts to surmount the learning curve was significantly less for the FH group (7.2 versus 16 attempts; p = 0.007) when using the moving F-test. CONCLUSIONS: The NG puncture allows a greater number of trainees to cross the learning threshold and offers the advantages of fewer posterior-wall punctures and skin punctures. The use of NG puncture may result in a shorter path to proficiency, allowing trainees to attempt needle puncture earlier and with a greater degree of safety.

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.