Ensuring Competency in Open Aortic Aneurysm Repair - Development and Validation of a New Assessment Tool.

OBJECTIVE: The aims of this study were to develop a procedure specific assessment tool for open abdominal aortic aneurysm (AAA) repair, gather validity evidence for the tool and establish a pass/fail standard. METHODS: Validity was studied based on the contemporary framework by Messick. Three vascular surgeons experienced in open AAA repair and an expert in assessment and validation within medical education developed the OPEn aortic aneurysm Repair Assessment of Technical Expertise (OPERATE) tool. Vascular surgeons with varying experiences performed open AAA repair in a standardised simulation based setting. All procedures were video recorded with the faces anonymised and scored independently by three experts in a mutual blinded setup. The Angoff standard setting method was used to establish a credible pass/fail score. RESULTS: Sixteen novices and nine experienced open vascular surgeons were enrolled. The OPERATE tool achieved high internal consistency (Cronbach's alpha .92) and inter-rater reliability (Cronbach's alpha .95) and was able to differentiate novices and experienced surgeons with mean scores (higher score is better) of 13.4 ± 12 and 25.6 ± 6, respectively (p = .01). The pass/fail score was set high (27.7). One novice passed the test while six experienced surgeons failed. CONCLUSION: Validity evidence was established for the newly developed OPERATE tool and was able to differentiate between novices and experienced surgeons providing a good argument that this tool can be used for both formative and summative assessment in a simulation based environment. The high pass/fail score emphasises the need for novices to train in a simulation based environment up to a certain level of competency before apprenticeship training in the clinical environment under the tutelage of a supervisor. Familiarisation with the simulation equipment must be ensured before performance is assessed as reflected by the low scores in the experienced group's first attempt.

A novel view to varicose veins pathogenesis: Proteomic profiling suggests a pivotal role of extracellular matrix degradation.

INTRODUCTION: Although morphological and anatomical studies indicate that venous wall weakening and subendothelial fibrosis characterize varicose veins (VV), the pathogenesis of VV remains poorly understood. The aim of this study is to obtain protein expression profiles in patients with VV and thereby get a step closer to understanding the pathogenesis of VV. METHODS: Specimens were obtained from total of 10 patients, that is, from 5 patients undergoing VV surgical stripping and from 5 non-VV patients undergoing bypass surgery. Specimens were collected from the same layers of venous wall. Proteins were extracted from each specimen and analyzed by ion mobility spectrometry (IMS-MS). In total, 1387 were identified and 486 proteins were identified in all samples. From these, 15 proteins were differentially expressed between VV and non-VV samples (p < .05) and 12 of these showed a fold change >1.5. RESULTS: Interestingly, among the differentially expressed proteins, only two proteins were significantly increased in the VV tissue, that is, GAPDH (p = .028, fold change 2.74), where several proteins involved in maintaining the homeostasis in the extracellular matrix, that is, the CXXC zinc finger protein 5 (CXXC5) and nucleoporin (SEH1) were prominently downregulated (p = .049, fold change 37.8, and p = .040, fold change 3.46). The downregulation in protein expression of CXXC5 and SEH1 as well as upregulation of GAPDH were validated by Western blotting. CONCLUSION: The identified differentially expressed proteins suggest an altered profile of the connective tissue proteins as well as an increased proteolytic enzyme activity which both may be central in the pathophysiology of varicose veins.

The toe-brachial index in the diagnosis of peripheral arterial disease.

BACKGROUND: Peripheral arterial disease (PAD) can be diagnosed noninvasively by segmental blood pressure measurement and calculating an ankle-brachial index (ABI) or toe-brachial index (TBI). The ABI is known to be unreliable in patients with vascular stiffness and fails to detect the early phase of arteriosclerotic development. The toe vessels are less susceptible to vessel stiffness, which makes the TBI useful. However, the diagnostic limits used in guidelines, clinical settings, and experimental studies vary substantially. This review provides an overview of the evidence supporting the clinical use of the TBI. METHODS: A review of the literature identified studies reporting the use of the TBI regarding guideline recommendations, normal populations, correlations to angiographic findings, and prognostic implications. RESULTS: Eight studies conducted in a normal population were identified, of which only one study used imaging techniques to rule out arterial stenosis. A reference value of 0.71 was estimated as the lowest limit of normal based on the weighted average in studies with preheating of the limbs. A further seven studies showed correlations of the TBI with angiographic findings. The TBI had a sensitivity of 90% to 100% and a specificity of 65% to 100% for the detection of vessel stenosis. Few studies investigated the value of the TBI as a prognostic marker for cardiovascular mortality and morbidity, and no firm conclusions could be made. Studies have, however, shown correlation between the TBI and comorbidities such as kidney disease, diabetes, and microvasculature disease. CONCLUSIONS: In contrast to the well-defined and evidence-based limits of the ABI, the diagnostic criteria for a pathologic TBI remain ambiguous. Although several guidelines and reviews of PAD diagnostics recommend a TBI <0.70 as cutoff, it is not strictly evidence-based. The current literature is not sufficient to conclude a specific cutoff as diagnostic for PAD. The current studies in normal populations and the correlation with angiography are sparse, and additional trials are needed to further validate the limits. Large-scale trials are needed to establish the risk of morbidity and mortality for the various diagnostic limits of the TBI.

Diagnostic accuracy of laser Doppler flowmetry versus strain gauge plethysmography for segmental pressure measurement.

OBJECTIVE: To assess the diagnostic accuracy of laser Doppler flowmetry (LDF) with mercury-in-silastic strain gauge plethysmography (SGP) as a reference test for measuring the toe and ankle pressures in patients with known or suspected peripheral arterial disease (PAD). METHODS: This was a prospective, randomized, blinded diagnostic accuracy study. Toe and ankle pressures were measured using both methods in 200 consecutive patients, who were recruited at our vascular laboratory over a period of 30 working days. Classification of PAD and critical limb ischemia (CLI) was made in accordance with TASC-II criteria. RESULTS: The LDF method demonstrated 5.8 mm Hg higher mean toe pressures than the SGP method for the right limb and 7.0 mm Hg for the left limb (both P < .001). There were no significant differences in the mean ankle pressures (both P > .129). The limits of agreement for the differences (SGP - LDF) were -31.7 to 20.2 mm Hg for right toe pressures, -28.0 to 14.0 mm Hg for left toe pressures, -25.5 to 22.8 mm Hg for right ankle pressures, and -26.9 to 24.6 mm Hg for left ankle pressures. A correlation analysis of the absolute pressures using the two methods showed an intraclass correlation coefficient of 0.902 (95% confidence interval [CI], 0.835-0.938) for right toe pressures, 0.919 (95% CI, 0.782-0.960) for the left toe pressures, 0.953 (95% CI, 0.937-0.965) for right ankle pressures, and 0.952 (95% CI, 0.936-0.964) for left ankle pressures. Cohen's Kappa showed an agreement in the diagnostic classification of κ = 0.775 (95% CI, 0.631-0.919) for PAD and κ = 0.780 (95% CI, 0.624-0.936) for CLI. CONCLUSIONS: LDF showed a good correlation with SGP over a wide range of toe and ankle pressures, as well as substantial agreement for the diagnostic classification of PAD including CLI.

Chronic mesenteric ischaemia: the importance of the individual mesenteric artery.

BACKGROUND: Chronic mesenteric ischaemia (CMI) is a vastly underdiagnosed condition that typically leads to postprandial abdominal pain and weight loss. The aim of the study was to explore the involvement of various mesenteric vessels in total splanchnic blood flow (SBF) and hepatic vein oxygenation. METHODS: Single-blinded comparative trial of 476 patients clinically suspected of CMI. Routine investigation included measurement of hepatic vein oxygen saturation, indirect measurement of the total splanchnic blood flow (SBF), using Fick's principle and the tracer [99m Tc]Mebrofenin, before and after a meal, and digital subtraction angiography. RESULTS: A total of 176 of the 476 patients (36%) had at least one angiographically significant stenosis (lumen reduction ≥70%). In patients with a significant one-vessel disease, the percentage having CMI according to SBF was 10% for a celiac trunk stenosis (n = 60), 50% for a superior mesenteric stenosis (n = 24) and 6% for an inferior mesenteric artery stenosis (n = 34). In patients with a significant two-vessel disease, the percentage with CMI according to SBF response was 92%, 18% and 79%, for no significant stenosis of the celiac trunk (n = 13), superior mesenteric artery (n = 17) and inferior mesenteric artery (n = 19), respectively. CONCLUSION: Patients with significant one- or two-vessel stenosis involving the superior mesenteric artery have a higher likelihood of CMI according to flow criteria and a greater postprandial decrease in hepatic vein saturation on average than patients with no involvement of the superior mesenteric artery.

Risk factors and haemodynamic variables in patients with low toe-brachial index but normal ankle-brachial index.

BACKGROUND AND AIMS: Classically, peripheral arterial disease (PAD) is diagnosed by a low ankle-brachial index (ABI), but the diagnosis can also be made based on toe-brachial index (TBI) measurements. The objective of this study was to characterize patients with low TBI but normal ABI, and chart potential underestimation of PAD prevalence by solitary use of ABI. METHODS: A total of 3739 consecutive patients with known or suspected PAD referred for ABI and TBI measurements in a four-year period were compared to an age- and gender matched control group (n = 17,340). RESULTS: In the patient cohort, 65.0% had low ABI, 20.5% had low TBI but normal ABI, and 14.5% had normal indices. When comparing the frequencies of comorbidities related to atherosclerotic disease (myocardial infarction, congestive heart failure, cerebrovascular disease, diabetes mellitus, chronic kidney failure), there were no significant differences among patients with low ABI or low TBI with normal ABI in any of the variables (all p > 0.06). Of the patients with low TBI and normal ABI, 18.7% were diagnosed with diabetes mellitus type I or II, and 8.2% with chronic kidney disease. CONCLUSIONS: Patients with low TBI but normal ABI represented 20.5% of patients referred with the suspicion of PAD. Furthermore, patients with low TBI but normal ABI presented similar comorbid characteristics to patients with low ABI, who have a well-described increased risk of cardiovascular morbidity and mortality. The solitary use of ABI underestimated the prevalence of PAD in the population, and PAD screening could potentially be improved by routine application of TBI.

The use of the "Objective Structured Assessment of Technical Skills" as an Assessment Tool Among Danish Vascular Surgeons in Training.

OBJECTIVE: The concept of the Objective Structured Assessment of Technical Skills (OSATS) is to quantify surgical skills in an objective way and, thereby, produce an additional procedure-specific assessment tool. Since 2005, a 2-day practical course for upcoming specialist registrars in vascular surgery has been obligatory. The aim of this study is to describe the results from a tailored OSATS test as a tool for the evaluation of practical skills during an intensive training session in a simple simulator box for vascular anastomoses. METHOD: Between 2005 and 2013, we registered the OSATS scores of all course participants. The following data were collected from the questionnaires: years as a candidate, months in vascular surgery or in another type of surgery, and the number of vascular anastomoses performed before the course. The assessment of surgical skills was conducted with an OSATS score template specifically made for this purpose. It consists of a 12-item table with a 5-point grading scale. OSATS score (points) and time for the procedure (OSATS time in min) were registered at baseline (OSATS I) and at the end of the course (OSATS II). RESULTS: OSATS scores were given in both OSATS I and OSATS II for the 83 trainees, and the mean difference was 8.1 points (95% CI: 6.7; 9.5, p < 0.001). OSATS time was given for 69 trainees, and the mean difference was 2.8 minutes (95% CI: 1.4; 4.2, p < 0.001). We found no relationship between years since graduation, months in any surgical specialty, or the experience with vascular anastomoses and outcomes. CONCLUSION: OSATS is a valuable tool for evaluating the advancement of technical skills during an intensive practical course in performing vascular anastomoses.

[Endovacular treatment of mycotic iliac aneurysm]. / Endovaskulær behandling af mykotisk arteria iliaca-aneurisme

No gold standard exists in the treatment of mycotic aorto-iliac aneurysms. Surgical debridement and revascularization with bypass remain as the most definitive surgical solution, but also carry a relatively high risk of perioperative morbidity as compared to an endovascular approach. We present a case story with a mycotic a. iliac aneurysm treated successfully with an endoluminal covered stent graft. The patient had severe co-morbidity that ruled out open surgery.

[Medical treatment of small abdominal aortic aneurysms]. / Medicinsk behandling af små abdominale aortaaneurismer.

Our expectation is that the numbers of diagnosed small abdominal aortic aneurysms (AAA) will increase in the future. Slowing down the progression of AAAs is of great interest as this could prevent cost-intensive and potential lethal operations. Recent studies indicate that modern medical treatment such as prevention for cardiovascular disease has a spin-off benefit by suppressing the expansion rate of AAAs. According to these studies ACE inhibitors, statins and nonsteroidal anti-inflammatory drugs may have effect, macrolides may have some effect while beta-blockers and calcium-channel blockers have no effect.