Training in vascular trauma surgery for non-vascular surgeons: Vascular trauma surgery skills course.

Background: The experience of general and trauma surgeons in vascular trauma management has decreased with sub-specialization of surgery and working hours restrictions. We introduce a vascular trauma surgery skills course established to train German military surgeons prior to their deployment to conflict areas. Methods: The intention and implementation of the vascular trauma course for non-vascular surgeons is described in detail. Results: In hands-on courses, participants learn and train basic vascular surgical techniques on more realistic extremity, neck, and abdominal models with pulsatile vessels. A fundamental and an advanced course each provide military as well as civilian surgeons from different non-vascular specialties with a surgical skill set including direct vessel sutures, patch angioplasty, anastomosis, thrombectomy, and resuscitative endovascular balloon occlusion of the aorta (REBOA) in order to render them capable of managing major vascular injuries. Conclusion: The experiences of this vascular trauma surgical skills course, initially established for military surgeons, can also be of use to all civilian general, visceral, and trauma surgeons occasionally facing traumatic or iatrogenic vascular injuries. Thus, the introduced vascular trauma course is valuable for all surgeons working in trauma centers.

[The marginal vein-Still a rare entity: case series of 16 patients]. / Die Marginalvene ­ nach wie vor eine seltene Entität: Fallserie von 16 Patienten.

BACKGROUND: The marginal vein (MV) is a congenital, predominantly venous vascular malformation, which is based on a lack of regression of the embryonic venous system in the lower extremities and is associated with a variety of complications. So far, no uniform treatment regimens have been described in the literature. OBJECTIVE: What are the treatment strategies and outcomes in patients with a MV? MATERIAL AND METHODS: In the period from 1 January 2008 to 31 December 2020, all patients treated at the University Hospital Augsburg with MV were retrospectively reviewed. RESULTS: The median age at the time of diagnosis was 14.8 years (3-42 years). Out of 16 patients 12 had a leg length difference, 75% of patients (12/16) already had chronic venous insufficiency (CVI) at the time of diagnosis of MV. Open surgical removal of MV was performed as first-line treatment in 31.3% (5/16) patients. The MV was primarily closed by endovenous laser therapy (EVLT) in 1/16 patients, 15/16 patients were treated with redo procedures and 2.6 ± 2.4 (mean±SD) redo procedures were performed per patient in follow-up. The mean follow-up was 8.1 years. DISCUSSION: In order to prevent/avoid progression of CVI and thrombosis prophylaxis, the MV should be closed/removed promptly after diagnosis. The use of conventional surgical techniques for the removal of MV seems to have an advantage over treatment with minimally invasive procedures in terms of the number of secondary interventions required.

[Resource requirements in the surgical treatment of COVID­19 patients at a university clinic of maximum care]. / Ressourcenbedarf bei der chirurgischen Behandlung von COVID­19-Patienten in der universitären Maximalversorgung.

BACKGROUND: Surgical procedures in patients suffering from coronavirus disease 2019 (COVID­19) are possible under strict hygiene and protective measures and are currently carried out regularly. This study examined how much additional work this involves. MATERIAL AND METHODS: A structured evaluation of 71 surgical procedures performed at the Augsburg University Hospital between 1 November 2020 until 31 December 2020 was carried out. The operations on COVID­19 patients were compared to procedures on non-COVID­19 patients with respect to temporal, structural and staff resources, exemplified by four interventions: transbrachial embolectomy, total hip arthroplasty (H-TEP), proximal femoral nail antirotation (PFN-A) and new implantations of cardiac pacemakers. RESULTS: The incision to suture times between the interventions in patients with COVID­19 and non-COVID­19 patients did not show any significant differences in any of the four interventions evaluated. The postoperative monitoring in the operating room, which is identified as time-consuming in many interventions, was often circumvented by postoperative transfer to the intensive care unit or by the use of local anesthetic procedures. For major operations, such as H­TEP, the preparation time was shown to be significantly longer (p = 0.037). Furthermore, there was a significantly higher requirement for anesthesia nursing personnel of 1.5 vs. 1.0 (p = 0.02). CONCLUSION: A quantification of the additional effort of operative treatment is difficult due to the already complex care of COVID­19 patients; however, it can be assumed that there is an increased need for additional human and structural resources due to the supply of material from outside the operating room, which is not documented in the standard recording.

[Treatment strategies and outcomes for injection-associated inguinal perivascular abscesses in intravenous drug addicts]. / Behandlungsstrategien und Ergebnisse bei injektionsassoziierten inguinalen perivaskulären Abszessen bei intravenös Drogenabhängigen.

BACKGROUND: Long-term drug users regularly present with deep inguinal vascular-associated abscesses due to continued drug injections utilizing superficial veins. The treatment of these complications continues to be a major medical challenge. So far no uniform treatment regimens have been described in the literature. OBJECTIVE: What are the treatment strategies and outcomes of injection-associated inguinal perivascular abscesses in drug addicts? MATERIAL AND METHODS: All drug users treated at the Augsburg University Hospital in the period between 1 January 2004 and 31 May 2019 were retrospectively reviewed and compared with the currently available literature. RESULTS: In this study 37 cases (male = 25, female = 12) could be included in the data collection after implementation of the inclusion criteria. The median age in the investigated patient population was 34.3 years. The 30-day mortality was 2.7% (1/37). The amputation rate was 2.8%. In the investigated collective 13 patients had arterial involvement, in 5 cases a ligature of arteries was primarily used and in another 5 cases a reconstruction using an autologous conduit graft was primarily performed. In another 3 cases an obturator bypass (1/3) was placed and a patch plasty (2/3). The patency rate after arterial reconstruction was 87.5% with a mean follow-up of 421 days. The overall complication rate was 51.4%. CONCLUSION: For vascular involvement an approach appropriate for the situation is meaningful. In addition to the elimination of complicated septic venous thromboses, the correction of arterial hemorrhages using autologous reconstruction measures seems promising.

[COVID-19 infection-Risk of thromboembolic complications]. / COVID-19-Infektion ­ Risiko für thrombembolische Komplikationen.

While the COVID-19 syndrome triggered by the SARS CoV­2 was initially seen predominantly as a pulmonary disease, the number of reports of vascular complications has recently increased. The aim of the present review article is to summarize the most relevant vascular complications in COVID-19 patients. These include venous and arterial thromboembolic events as well as local thromboses, which can form directly on the endothelium at the site of cytokine release. A generalized coagulopathy also appears to promote this thrombogenic condition. With a rate of approximately 20%, deep vein thrombosis (DVT) of the leg is one of the most common thromboembolic events in COVID-19 patients requiring intensive care treatment. In addition, arterial events, such as stroke or acute coronary syndrome were also observed in COVID-19 patients with pre-existing vascular disease. Children rarely have vascular complications, but a systemic immune response similar to the Kawasaki syndrome and toxic shock syndrome has been reported. According to current data, the risk of thromboembolic events in hospitalized COVID-19 patients is significantly increased, making thrombosis prophylaxis with low molecular weight or unfractionated heparin necessary. If pharmaceutical thrombosis prophylaxis is contraindicated, intermittent pneumatic compression should be used. In addition, in patients admitted to the hospital with suspected or proven SARS-CoV­2 infection, the determination of D­dimers and, in the case of positive results, broad indication for compression sonography of the deep leg veins are recommended. This allows to detect and treat DVT at an early stage. The treatment of thromboses should be carried out according to current guidelines with therapeutic anticoagulation. Further studies and registries are needed to improve the understanding of the relationship between COVID-19 infection and the occurrence of thromboembolic events.

[Increased risk of deep vein thrombosis in intensive care unit patients with CoViD-19 infections?-Preliminary data]. / Erhöhtes Risiko für tiefe Beinvenenthrombosen bei Intensivpatienten mit CoViD-19-Infektion? ­ Erste Daten.

BACKGROUND: The incidence of deep vein thrombosis (DVT) in CoViD-19 patients in intensive care units (ICU) has so far been investigated in only a few studies. Prospective comparative studies with non-CoViD-19 ICU patients are completely lacking. OBJECTIVE: Evaluation of the incidence of DVT in ICU patients with CoViD-19 compared to non-CoViD-19 ICU patients who were treated in the University Hospital Augsburg during the same period. In addition, the aim was to investigate what type of anticoagulation was present in CoViD-19 patients at the time the DVT occurred and to what extent DVT is associated with increased mortality in this patient population. MATERIAL AND METHODS: In this prospective single center study, which was conducted between 18 April 2020 and 30 April 2020, 20 SARS-CoV2 positive patients were compared with 20 non-CoVid-19 patients in the ICU with respect to the occurrence of DVT. For this purpose, demographic data, laboratory parameters, and clinical outcomes were recorded and evaluated. RESULTS: The rate of DVT in the investigated patient collective was markedly higher in patients with SARS-CoV2 (CoViD-19 patients 20% vs. non-CoViD-19 patients 5%). Both DVT and elevated D­dimer levels were associated with increased mortality in the present study. CONCLUSION: We recommend the determination of D­dimer levels and, in the case of elevated levels, the broad indication for compression sonography of the deep leg veins on admission of patients with suspected or confirmed SARS-CoV2. In this way DVT in the setting of CoViD-19 can be recognized early and therapeutic anticoagulation can be started. All inpatient CoViD-19 patients should receive thrombosis prophylaxis with low molecular weight heparin. Further studies on point of care methods (TEG®, ROTEM®) for the detection of hypercoagulability in SARS-CoV2 are necessary.

Vascular reconstruction after retroperitoneal and lower extremity sarcoma resection.

PURPOSE: Soft tissue sarcomas (STS) of the retroperitoneum and the lower limb with invasion of major blood vessels are very rare malignancies. This study analyses the outcome of patients with vascular replacement during resection of STS of the retroperitoneum and the lower extremity with either arterial or concomitant arterial and venous infiltration. METHODS: Patients with vascular replacement during resection of sarcoma of the retroperitoneum and the lower extremity between 1990 and 2014 were included in this retrospective single center study. Patients with a sole infiltration of a major vein were excluded. The follow up was obtained from medical records, the general practitioner and a clinical examination whenever possible. The main endpoints were survival, graft patency and the rate of major amputations. RESULTS: Fourty seven patients were included in this study. Twenty patients have received an operation for a retroperitoneal STS, twenty seven for a STS of the lower extremity. The median follow-up was 24.5 months. The median survival was 113 months with a median tumor-free survival of 25 months. The two-year patency for arterial bypasses in the retroperitoneum and the lower extremity was 88% and 66%, respectively. Limb salvage rate was 89%. CONCLUSIONS: Invasion of major blood vessels is no contraindication for a resection of a STS in the retroperitoneum and the lower extremity, but it is accompanied by a high postoperative morbidity. Since surgical resection is the only curative therapy in these patients, it should also be offered to patients with infiltration of major blood vessels.

[Prevention of aortic erosion by a bone cement skid : Thoracic endovascular aortic repair following kyphoplasty]. / Pelottierung der A. thoracica descendens durch einen Zementsporn : Endovaskuläre Behandlung nach Kyphoplastie.

The underlying case report describes the successful endovascular prevention of an aortic injury by a bone cement skid after kyphoplasty. The intervention was performed in order to prohibit fatal aortic rupture or embolisation and underlines the role of vascular surgery techniques in interdisciplinary clinical networks.

[Management of bleeding and infections in the context of visceral surgery]. / Management von Blutungen und Infektionen im Rahmen viszeralchirurgischer Operationen.

Bleeding and vascular infections are serious potential complications during abdominal general surgery. The management of bleeding depends on the extent and localization and can range from the application of hemostatics to vascular sutures, interpositioning and ligatures. The use of prosthetic biomaterials implanted endoluminally or during open reconstruction permits palliation of potentially fatal conditions. The overall incidence of infections involving vascular prostheses is relatively low because of routine antibiotic prophylaxis prior to surgery, refinements in sterilization and packaging of devices and careful adherence to aseptic procedural and surgical techniques. When infections occur detection and definitive therapy of the vascular prosthesis are often delayed and the management is complex and tedious. Infections involving vascular prostheses are difficult to eradicate and in general, surgical therapy is required often coupled with excision of the prosthesis. Keys to success include accurate diagnostics to identify the organism and extent of graft infections, specific long-term antibiotic therapy and well-planned surgical interventions to excise and replace the infected graft and sterilize the local tissue. Regardless of the technique used to eradicate graft infections, success is measured by patient survival, freedom from recurrent infection and patency of revascularization. Even when treatment is successful, the morbidity associated with vascular graft infections is considerable. Aortoenteric fistulas (AEF) are a rare (incidence < 1.5 %) but often fatal complication. Primary diagnosis of AEF remains difficult. Computed tomography (CT) and fluorodeoxyglucose positron emission tomography CT (FDG-PET-CT) are the diagnostic tools of choice. Therapy consists of an urgent individualized interdisciplinary surgical approach with primary axillofemoral bypass and secondary prosthesis explantation or in situ replacement and subsequent bowel resection. Endovascular aortic repair (EVAR) is reserved for primary aortoenteric fistulas in patients with no signs of infection or in emergency cases as a bridging method.

Finite element analysis in asymptomatic, symptomatic, and ruptured abdominal aortic aneurysms: in search of new rupture risk predictors.

OBJECTIVES: To compare biomechanical rupture risk parameters of asymptomatic, symptomatic and ruptured abdominal aortic aneurysms (AAA) using finite element analysis (FEA). STUDY DESIGN: Retrospective biomechanical single center analysis of asymptomatic, symptomatic, and ruptured AAAs. Comparison of biomechanical parameters from FEA. MATERIALS AND METHODS: From 2011 to 2013 computed tomography angiography (CTA) data from 30 asymptomatic, 15 symptomatic, and 15 ruptured AAAs were collected consecutively. FEA was performed according to the successive steps of AAA vessel reconstruction, segmentation and finite element computation. Biomechanical parameters Peak Wall Rupture Risk Index (PWRI), Peak Wall Stress (PWS), and Rupture Risk Equivalent Diameter (RRED) were compared among the three subgroups. RESULTS: PWRI differentiated between asymptomatic and symptomatic AAAs (p < .0004) better than PWS (p < .1453). PWRI-dependent RRED was higher in the symptomatic subgroup compared with the asymptomatic subgroup (p < .0004). Maximum AAA external diameters were comparable between the two groups (p < .1355). Ruptured AAAs showed the highest values for external diameter, total intraluminal thrombus volume, PWS, RRED, and PWRI compared with asymptomatic and symptomatic AAAs. In contrast with symptomatic and ruptured AAAs, none of the asymptomatic patients had a PWRI value >1.0. This threshold value might identify patients at imminent risk of rupture. CONCLUSIONS: From different FEA derived parameters, PWRI distinguishes most precisely between asymptomatic and symptomatic AAAs. If elevated, this value may represent a negative prognostic factor for asymptomatic AAAs.

Cross-flow determination by transcranial Doppler predicts clamping ischemia in patients undergoing carotid endarterectomy.

AIM: Aim of the paper was to assess the reliability of preoperative cross-flow determination by transcranial Doppler measurement (TCD) to detect clamping ischemia in patients undergoing carotid endarterectomy with selective shunting. METHODS: Retrospective one-to-one matched-pair analysis of 72 patients undergoing carotid endarterectomy with preoperative TCD scanning. Matching criteria were gender, degree of contralateral stenosis and the type of stenosis (asymptomatic or symptomatic). RESULTS: Patients in need for a secondary shunt insertion had significantly less cross-flow in preoperative TCD measurement (N.=14; 38.89%) compared to the control group (N.=32; 88.89%: P=0.0001%). The sensitivity of the cross-flow determination to predict clamping ischemia was 88.9%, the specificity 61.1%. The risk of developing a clamping ischemia in the absence of a cross-flow was 12 fold higher (OR: 12.6; 95% CI: 3.7-43.3). The existence of circulatory impairment of the MCA was associated with the presence of a collateral flow in the ACoA (OR 3.21; P=0.0531; likelihood ratio test 0.0481). Other factors like renal insufficiency, the degree of stenosis or the stump pressure showed no association with a cross-flow of the ACoA in a multivariate model. CONCLUSION: TCD scanning is highly reliable to detect cross-flow prior to carotid surgery and thus helpful to identify patients at risk for clamping ischemia and need for shunting.

A novel strategy to translate the biomechanical rupture risk of abdominal aortic aneurysms to their equivalent diameter risk: method and retrospective validation.

OBJECTIVE: To translate the individual abdominal aortic aneurysm (AAA) patient's biomechanical rupture risk profile to risk-equivalent diameters, and to retrospectively test their predictability in ruptured and non-ruptured aneurysms. METHODS: Biomechanical parameters of ruptured and non-ruptured AAAs were retrospectively evaluated in a multicenter study. General patient data and high resolution computer tomography angiography (CTA) images from 203 non-ruptured and 40 ruptured aneurysmal infrarenal aortas. Three-dimensional AAA geometries were semi-automatically derived from CTA images. Finite element (FE) models were used to predict peak wall stress (PWS) and peak wall rupture index (PWRI) according to the individual anatomy, gender, blood pressure, intra-luminal thrombus (ILT) morphology, and relative aneurysm expansion. Average PWS diameter and PWRI diameter responses were evaluated, which allowed for the PWS equivalent and PWRI equivalent diameters for any individual aneurysm to be defined. RESULTS: PWS increased linearly and PWRI exponentially with respect to maximum AAA diameter. A size-adjusted analysis showed that PWS equivalent and PWRI equivalent diameters were increased by 7.5 mm (p = .013) and 14.0 mm (p < .001) in ruptured cases when compared to non-ruptured controls, respectively. In non-ruptured cases the PWRI equivalent diameters were increased by 13.2 mm (p < .001) in females when compared with males. CONCLUSIONS: Biomechanical parameters like PWS and PWRI allow for a highly individualized analysis by integrating factors that influence the risk of AAA rupture like geometry (degree of asymmetry, ILT morphology, etc.) and patient characteristics (gender, family history, blood pressure, etc.). PWRI and the reported annual risk of rupture increase similarly with the diameter. PWRI equivalent diameter expresses the PWRI through the diameter of the average AAA that has the same PWRI, i.e. is at the same biomechanical risk of rupture. Consequently, PWRI equivalent diameter facilitates a straightforward interpretation of biomechanical analysis and connects to diameter-based guidelines for AAA repair indication. PWRI equivalent diameter reflects an additional diagnostic parameter that may provide more accurate clinical data for AAA repair indication.

The expression of glycophorin A and osteoprotegerin is locally increased in carotid atherosclerotic lesions of symptomatic compared to asymptomatic patients.

The aim of this study was to evaluate in detail the histopathological characteristics of endarterectomized carotid atherosclerotic lesions in symptomatic versus asymptomatic patients. Twenty carotid lesions, 10 from asymptomatic and 10 from symptomatic patients who underwent carotid endarterectomy were classified according to histomorphological features. Samples were analyzed for intraplaque localization and for the expression of proteins associated with inflammation, such as CD68, interleukin (IL)-1ß, tumor necrosis factor-α (TNF-α), pentraxin-3 (PTX-3), nuclear factor-κB (NF-κB), C-reactive protein (CRP) and transforming growth factor-ß (TGF-ß), as well as for proteins associated with vascular remodelling, such as matrix-metalloproteinase-9 (MMP-9), glycophorin A (GYPA), osteoprotegerin (OPG), vascular cell adhesion molecule-1 (VCAM-1), endothelin-1 (ET-1), vascular endothelial growth factor (VEGF) and vascular smooth muscle cell actin (VSMA). Corresponding expression scores were compared between the symptomatic and asymptomatic patients and evaluated statistically. The expression of all 14 evaluated markers was significantly elevated in the border zone adjacent to the mixed plaque compared with the unaffected control area of the same sample (p<0,016). The expression scores of GYPA and OPG were significantly higher in the border zones around the calcified (GYPA, p=0.035; OPG, p=0.043) and mixed (GYPA, p<0.001; OPG, p=0.007) plaque zones of symptomatic patients compared to asymptomatic patients. No difference in expression scores was observed for any of the analyzed inflammatory marker proteins between the border zones of symptomatic and asymptomatic patients. In conclusion, the increased expression of GYPA, indicating intraplaque hemorrhage, and OPG, indicating the transdifferentiation of vascular cells, in carotid atherosclerotic lesions may be associated with an increased risk of plaque instability.

[Endovascular therapy of para-anastomotic aneurysms of the aorta. Technical options]. / Endovaskuläre Therapie paraanastomaler aortaler Aneurysmen. Technische Möglichkeiten.

BACKGROUND: Open repair of para-anastomotic aneurysms (pAAA) after conventional aortoiliac repair is associated with a high perioperative mortality and morbidity. Endovascular treatment options have evolved over the last decade. The aim of this article is to demonstrate and review these endovascular strategies. MATERIAL AND METHODS: Between 01/2009 and 06/2012, a total of 12 patients received endovascular treatment for proximal (n = 7) or distal (n = 5) pAAA (n = 2 contained rupture). A retrospective analysis of these patients was performed. Median age was 71.5 years (range 55-87 years). The median time interval between primary operation and endovascular repair of the pAAA was 15 years (range 1-31 years) and median follow-up was 1.3 years (range 0 days - 3 years). Endovascular exclusion of the pAAA was achieved by implantation of an aortouniiliac endograft (n = 6), chimney graft (n = 1), fenestrated endograft (n = 2) and iliac extension (n = 3). RESULTS: Technical success could be achieved in all patients and in-hospital mortality was 16.8  % (n = 2). No patient required a reintervention but during follow-up one additional patient died due to gastrointestinal bleeding. No primary or secondary type I/III endoleaks were observed. CONCLUSIONS: Despite a not negligible mortality rate endovascular treatment of para-anastomotic aneurysms and anastomotic pseudoaneurysms appears to be a safe alternative for conventional open repair.

Decision-making and techniques in hypogastric artery revascularization.

The aim of this article was to describe and discuss the currently available endovascular and open surgical techniques to preserve or occlude the hypogastric artery during aortoiliac aneurysm repair and thus support the process of decision-making in hypogastric artery revascularization.

Technical aspects of EVAR for infrarenal AAA.

Technical aspects are crucial for planning and performing successful endovascular repair of abdominal aortic aneurysms (AAA). Planning should be based on high-quality computed tomography angiography scans with a slice thickness of ≤ 1 mm. However, even without a workstation for image postprocessing, important angle estimations can be easily performed. Several devices are available today to treat abdominal aneurysms. In most elective cases all currently available 3rd generation devices perform comparably if minimal requirements are kept in mind. A safe and technically precise implantation requires cooperation with the involved anesthesiologist in order to manage anticoagulation, blood pressure regulation in general and in currently evolving regional anesthesia. Modern endograft implantation involves highly technical resources, for example guide wires or catheters. Beside patient selection, an optimal procedure planning, graft model choice and endovascular skills are mandatory aspects. In the near future, further improvements in device design and deployment mechanism will allow better device alignment, paving the way for an even broader application of endovascular aneurysm repair (EVAR).

Penetrating aortic ulcer: defining risks and therapeutic strategies.

In addition to classic aortic dissection and intramural hematoma, acute aortic syndrome also includes penetrating aortic ulcers (PAU). The recent advent of highly detailed axial imaging allows closer assessment of PAU and its pathophysiology. However, there is still ongoing discussion about the natural history of the disease, leading to challenging questions concerning the optimal treatment strategy, particularly in asymptomatic patients. In this review, current indications for treatment, with an emphasis on PAU repair in the endovascular era, are discussed.

[Aorto-enteric fistula: an interdisciplinary practical approach]. / Ein praktischer Ansatz zur interdisziplinären Therapie der aorto-enteralen Fistel.

Aorto-enteric fistulas (AEF) are a rare but often -fatal complication. The primary diagnosis of AEF remains difficult. Computed tomography and FDG-PET / CT (fluorodeoxyglucose positron emission computed tomography) are the diagnostic tools of choice. Therapy consists of an urgent individual interdisciplinary surgical approach with primary axillo-femoral bypass and secondary prosthesis explantation or in situ replacement and consecutive bowel resection. Endovascular aortic repair (EVAR) is reserved for primary -aorto-enteric fistulas in patients without signs of infection or in emergency cases as a bridging meth-od. A systematic review of the literature from 1990 to 2009 was performed by medline -research (pubmed) to analyse diagnostic and treatment strategies for aorto-enteric fistulas. A practical, interdisciplinary diagnostic and therapeutic algorithm was created in accordance with the analysed results.