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Simulation technology has a well-defined role in nonmedical professions such as aviation and over the last two decades has permeated medical training. The most successful surgical simulation is in the fields of laparoscopic and endovascular surgery. These two-dimensional scenarios, as in the aviation industry, lend themselves to simulation. Open simulators have been met with more resistance than their laparoscopic counterparts because of the difficulties in simulating the three-dimensional field. Engaging in persistent practice is what makes the expert and all trainees should aspire to this. Without knowing, all surgical trainees have engaged in deliberate practice when first learning to tie surgical knots. This deliberate practice should be used in all aspects of vascular surgical practice, and it is no longer acceptable to perform procedures such as arterial anastomoses for the first time on patients. Simulators exist for all aspects of vascular surgical training and vary in complexity and price. Some of these simulators are suitable for use at home or in a skills laboratory whereas others are more suitable for use in a specialized skills center. Training on these simulators can be offered at a local level or at a regional level in the skills center. Where surgical procedures are not commonly performed or expertise is required for a new innovation, it is more appropriate to have national or internationally based workshops under the auspices of surgical boards or societies. Simulation of crisis management, well known in aviation, has also been applied to vascular surgical practice and can offer benefit to senior trainees even when their performance on a noncrisis simulator has reached a plateau. This article identifies the areas where simulation in open vascular surgery can benefit the trainee.

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OBJECTIVE: This study investigates the effects of surgeons' stress levels and coping strategies on surgical performance during simulated operations. METHODS: Thirty surgeons carried out each a non-crisis and a crisis scenario of a simulated operation. Surgeons' stress levels were assessed by several measures: self-assessments and observer ratings of stress, heart rate, heart rate variability, and salivary cortisol. Coping strategies were explored qualitatively and quantified to a coping score. Experience in surgery was included as an additional predictor. Outcome measures consisted of technical surgical skills using Objective Structured Assessment of Technical Skill (OSATS), nontechnical surgical skills using Observational Teamwork Assessment for Surgery (OTAS), and the quality of the operative end product using End Product Assessment (EPA). Uni- and multivariate linear regression were used to assess the independent effects of predictor variables on each performance measure. RESULTS: During the non-crisis simulation, a high coping score and experience significantly enhanced EPA (beta1, 0.279; 0.009-0.460; P= 0.04; beta2, 0.571; 4.328-12.669, P< 0.001; respectively). During the crisis simulation, a significant beneficial effect of the interaction of high experience and low stress on all performance measures was found (EPA: beta, 0.537; 2.079-8.543; OSATS: beta, 0.707; 8.708-17.860; OTAS: beta, 0.654; 13.090-30.483; P< 0.01). Coping significantly enhanced nontechnical skills (beta, 0.302; 0.117-1.624, P= 0.03). CONCLUSIONS: Clinicians' stress and coping influenced surgical performance during simulated operations. Hence, these are critical factors for the quality of health care.

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BACKGROUND: High fidelity simulations within the operating theatre (OT) require physical infrastructure and a full OT team. Such teams place heavy demands on clinical service. Research and training programmes in our surgical department were often compromised by the late cancellation of anaesthetists. AIMS: This paper describes and evaluates a training programme in which actors were trained as simulated anaesthetists. METHODS: The training programme was developed, piloted and implemented in a surgical education programme. Evaluation consisted of interviews with actors after the series of simulations. Surgical participants were not informed that the anaesthetist was an actor until after the simulation when they completed an interview and a 10-point authenticity scale (1 = not at all to 10 = highly authentic). RESULTS: Three actors played the role of anaesthetists in 34 scenarios with 17 surgeons in simulations of carotid endarterectomy. Although initially anxious about their role, actors found the training programme valuable and came to feel confident. Mean ratings of anaesthetist authenticity was 8.1 (Range 2-10). Surgeons' comments showed that in most scenarios they found the anaesthetist's performance highly authentic. CONCLUSIONS: Although this study demonstrates the feasibility of using actors as anaesthetists in high fidelity surgical simulations, there are also limitations. Factors contributing to success included: selective actor recruitment; written training materials; formal OT orientation, audio link between the control room and the actor; the opportunity to rehearse; and, structured observations.

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The purpose of this study was to estimate wall shear stress (WSS) in individual vessels of the venous circulation of the calf and quantify the effects of elastic compression based on change of vessel geometry and velocity waveform. The great saphenous vein and either a peroneal or posterior tibial vein have been imaged in four healthy subjects using magnetic resonance imaging, with and without the presence of a grade 1 medical stocking. Flow through image-based reconstructed geometries was numerically simulated for both a range of steady flow rates and ultrasound-derived transient velocity waveforms, scaled to give a standardized time averaged flow rate. For steady flow, the stocking produced an average percentage increase in mean WSS of approximately 100% in the great saphenous vein across a range of 0.125-1.25 ml/s. The percentage increase in the peroneal/posterior tibial veins varied from 490 to 650% across a range of 0.5-5 ml/s. In addition, application of the stocking eliminated periods of very low or zero flow from the transient waveforms. The average minimum value of WSS in all vessels without the stocking was <0.1 Pa. With the stocking, this was increased to 0.7 Pa in the great saphenous and 0.9 Pa in the peroneal/posterior tibial veins. The pathophysiological effects of these changes are discussed. In conclusion, the flight stocking was effective in raising venous WSS levels in prone subjects, and this effect was much more pronounced in the deep vessels. The stocking also tended to prevent cessation of flow during periods of increased downstream pressure produced by respiration.

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OBJECTIVE: We review our ongoing experience with a transabdominal stent repair of complex thoracoabdominal aneurysms (Crawford type I, II, and III) with surgical revascularization of visceral and renal arteries. METHODS: A retrospective review was conducted of prospectively collected data from 29 consecutive patients who underwent an attempted visceral hybrid procedure between January 2002 and April 2005. Twenty-two patients were elective, four were urgent (symptomatic), and three were emergent (true rupture). The median patient age was 74 years (range, 37 to 81 years). The aneurysms were Crawford type I in 3, type II in 18, type III in 7, and type IV in 1. Previous aortic surgery had been performed in 13 (45%) of 29 and included aortic valve and root replacement in 3, TAA repair in 1, type I repair in 1), type IV repair in 3, type B dissection in 2, infrarenal aneurysm in 5, and right common iliac aneurysm in 1. Severe preoperative comorbidity was present in 23 (80%) of 29: chronic renal impairment in 5, severe chronic obstructive pulmonary disease in 6, myocardial disease in 11 at New York Heart Association grade II (6) and grade III (5), and Marfan's syndrome in 6. Twenty-six patients (90%) had a completed procedure. In two patients, myocardial instability prevented completion of the procedure despite extensive preoperative cardiac assessment, and in one, poor flow in the true lumen of a chronic type B dissection prevented anastomosis of the revascularization grafts. Exclusion of the full thoracoabdominal aorta was achieved in all 26 completed procedures and extended to include the iliac arteries in four, with revascularization of coeliac in 26, superior mesenteric artery in 26, left renal artery in 21, and right renal artery in 21). RESULTS: There was no paraplegia < or =30 days or during inpatient admission, and elective and urgent mortality was 13% (3/23). All of the patients with ruptured thoracoabdominal aneurysms died < or =30 days. Major complications included prolonged respiratory support (>5 days) in 9, inotropic support in 4, renal impairment requiring temporary support in 2 and not requiring support in 2, prolonged ileus in 2, resolved left hemispheric stroke in 1, and resection of an ischemic left colon in 1. Median blood loss was 3.9 liters (range, 1.2 to 13 liters). The median ischemia time was 15 minutes (range, 13 to 27 minutes) for the superior mesenteric and coeliac arteries and 15 minutes for the renal arteries (range, 13 to 21 minutes). The median hospital stay was 27 days (range, 16 to 84 days). Follow-up was a median of 8 months (range, 2 to 31 months), with 92 of 94 grafts patent. Six patients were found to have a type I endoleak. In four, this was a proximal leak, and stent extension in three reduced, but did not cure, the endoleak. One patient with a distal type I endoleak was successfully treated by embolization. Four type II endoleaks resolved without intervention, and one was treated by occlusion coiling of the origin of the left subclavian artery. A single late type III endoleak was found. CONCLUSION: Early results of visceral hybrid stent-grafts for types I, II, and III thoracoabdominal aneurysms are encouraging, with no paraplegia in this particularly high-risk group of patients. These results have encouraged us to perform the new procedure, in preference to open surgery, in Crawford type I, II, and III thoracoabdominal aortic aneurysms.

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BACKGROUND: There is growing focus on surgical technical competence and the means by which we are able to measure it. Ongoing studies have shown a plateau effect with increasing experience of the operator. The aim of this study was to assess the technical competence of five groups of surgeons with increasing experience and validate a new rating tool for use in surgical assessment. METHODS: Fifty surgeons performed a saphenofemoral junction ligation on a synthetic groin model. The procedure was videotaped, blinded, and reviewed independently by three assessors. Performance was assessed using a previously validated global rating scale of generic surgical skill. In addition, each procedure was rated with the procedure-specific Imperial College Evaluation of Procedure-Specific Skill (ICEPS) rating scale to establish the construct validity (ability to differentiate on the basis of skill) and inter-observer reliability. RESULTS: Both rating scales showed improved scores with ascending grades (P < .001) and demonstrated a high inter-observer reliability both for generic and procedure-specific skill (alpha = 0.97 and alpha = 0.96, respectively). Total operative scores demonstrated significant differences between surgeons in postgraduate years 1 and 2 and surgeons in years 3 and 4 and also between newly appointed and experienced consultants (P < .041). Procedure-specific performance showed a plateau effect at the registrar level. Generic skill continued to improve, and significant differences were seen between newly appointed and senior consultants (P < .026). CONCLUSION: This study shows that surgical performance continues to improve significantly beyond consultancy, and the data suggest that generic and procedural performance continue to improve, with significant improvement in the former with increasing experience. The ICEPS rating scale demonstrates construct validity and a high inter-observer reliability supporting its use in formative and summative assessment.

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BACKGROUND: Simulation for training and assessing clinicians is increasing but often overlooks the patient's perspective. In this paper, actors are trained to portray patients undergoing operations under local anesthetic within a high-fidelity simulated operating theater (SOT). There are few published accounts of approaches to case development and simulated patient (SP) training. We assess the feasibility of SPs playing complex surgical roles and evaluate a three-phased framework for case development and SP training. METHODS: We developed two patient roles for carotid endarterectomy (CEA) under local anesthesia. In all cases, the conscious patient interacted with the surgical team throughout the procedure. SPs were trained to simulate routine and crisis situations, using our framework. After consulting with each SP, surgeons "performed" a CEA upon a model attached to the SP. Evaluation of the framework used interviews, observations, and written evaluations with SPs, surgeons, and the project team. Descriptive statistics summarize surgeons' ratings of realism and qualitative data are analyzed thematically. RESULTS: In all, 46 simulations were conducted with 23 surgeons and three SPs. Real patient interview transcripts provided SPs with authentic information. The SP framework was easy to use, SP training was successful and surgeons' rated SP realism very highly. SPs valued guidance from the SOT control room using an audiolink. CONCLUSIONS: Actors can be trained to portray patients undergoing complex procedures. Our framework for case development and SP training was effective in creating realistic roles. Future studies could evaluate this framework for additional procedures.

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The role of stasis in venous disease is undisputed, yet surprisingly, its haemodynamic quantitation remains largely undefined. We investigated the phenomenon of venous stasis in the lower limb upon sitting and standing and project its implications to economy class aircraft passengers. 26 normal limbs, 13 subjects, age 29-54, selected after duplex, plethysmography and ABPI, had peak[V(peak)], mean[V(mean)] and minimum[V(min)] velocities, volume-flow[Q(venous)], pulsatility index [PI(venous)] and diameter obtained on horizontal, sitting (as in economy aircraft seats) and standing with duplex, at popliteal, femoral[FV] and common femoral[CFV]veins [differences in median %]. V(peak), V(mean) and Q(venous) decreased from horizontal to sitting in the CFV [57%, 71%, 31%, respectively], FV [51%, 70%, 34%] and popliteal [31%, 58%, 42%] (all, p<.001). V(peak),V(mean) and Q(venous) decreased further from sitting to standing in the CFV [26%, 44%, 25%, respectively], FV [21%, 42%, 27%] and popliteal [14%, 42%, 20%] (all, p <.001). Diameter, V(min) and PI(venous) increased from horizontal to sitting in the CFV [50%, 63%, 38%, respectively], FV [39%, 23%, 66%] and popliteal [21%, 14%, 84%] (all, p <.001)]. Diameter, V(min) and PI(venous) increased further from sitting to standing in CFV [10%, 22%, 19%, respectively; p =.004], FV [12%, 68%, 2%[ns]; p <.001)] and popliteal [14%, 50%, 24%; p =.017]. In all postures: V(peak), V(mean), Q(venous) and diameter at CFV exceeded FV (p <.025) and popliteal (p <.001) ones; also those at FV exceeded the popli-teal ones (p =.003), except for the diameter on horizontal. V(min) in popliteal was higher than in CFV (p =.003) or FV (p <.025), on horizontal and standing. PI(venous) in CFV was lower than in FV or popliteal (p <.025) on sitting. Right to left differences non-significant. [Wilcoxon(+Bonferroni) test: significance at p <.025] A shift from horizontal to sitting generates a most significant attenuation in Q(venous),V(peak) and V(mean) linked to a reciprocal increase in V(min), PI(venous) and vein diameter, with further exacerbation on standing. V(peak),V(mean) and Q(venous) decline with distance from groin enhancing venous stasis in the periphery. By restricting activation of the natural venous pumps, sitting cramped during long flights may protract the status of haemodynamic stagnation sustained on dependency which paired with marked venous dilatation generates a milieu that may promote thrombogenesis.

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Cerebral reperfusion following carotid endarterectomy occasionally causes cerebral hyperperfusion syndrome. This is a rare but important complication and this case report acted as a stimulus for a literature review of this problem. A 60-year-old businessman had a right carotid endarterectomy for a severe stenosis which had caused recurrent attacks of amaurosis fugax. The left internal carotid artery had occluded asymptomatically. The operation and his immediate postoperative recovery were entirely uneventful but he developed right-sided headaches and focal sensory motor seizures. He subsequently recovered. Hemodynamically compromised patients appear to be at greater risk and as the mortality of the operation is reduced and more complex patients are treated, it is likely that this unusual complication will increase in incidence.

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