[Pelvic vein thrombosis : Current treatment options and importance of recanalization procedures]. / Beckenvenenthrombose : Aktuelle Therapieoptionen und Stellenwert rekanalisierender Verfahren.

Venous thrombosis is a frequent disorder. A distinction is made between an acute phase of the disease and a chronic manifestation, the postthrombotic syndrome. In particular, proximal venous thrombosis/pelvic vein thrombosis can cause a life-threatening pulmonary embolism during the acute phase of the disease. The postthrombotic syndrome is characterized by the remodeling of the affected venous section, which is often caused by inflammation. Locally, the typical clinical finding is caused by scarred stricture of the vein with restricted drainage and peripheral venous hypertension. Acute thrombosis should be primarily treated by therapeutic anticoagulation and compression therapy of the affected extremity. The duration of these measures depends on clinical presentation, cause (provoked, unprovoked) and risk factors for venous thrombosis/recurrent thrombosis. Venous revascularization procedures are important both in the acute phase of the disease and in the treatment of postthrombotic syndrome. The recanalization treatment is mostly carried out as an endovascular or hybrid intervention and venous bypass procedures are reserved for special situations.

[Hospital nursing personnel staffing and patient outcome]. / Pflegepersonalausstattung des Krankenhauses und Patientenoutcome.

OBJECTIVE: The purpose of this review is to comment on the association between hospital nursing personnel staffing and patient outcomes, including the avoidance of errors and complications. METHODS: A literature search was carried out in the Medline database on publications from the last 10 years on nursing personnel staffing. RESULTS: Only overviews and observational studies on the topic were available and no controlled or prospective surveys. Most investigators assumed that there was an inverse relationship between low nursing staff levels of hospital wards and intensive care and adverse outcomes, including higher mortality rates; however, there is no clear significance for this assumption and evidence-based definitive lower limits for nursing staff cannot be given due to a lack of randomized trials. The causes for unfavorable results in the case of inadequate nursing personnel staffing include hygiene deficiencies, orders not followed and unfulfilled nursing and monitoring measures. Furthermore, staff overload leads to staff dissatisfaction and burnout, which also has a negative impact on the results. Most studies required a maximum patient to nurse ratio of 2:1 for the intensive care unit and an average ratio of not more than 8:1 for surgical wards. With respect to these requirements, changing personnel needs must be considered depending on the current state of the patients being cared for, which enabled all investigators to require a flexible roster design; approval for fixed statutory lower limits for nursing staff was low. The level of education of the nursing staff also played an essential role as qualified nursing staff cannot be replaced at will by less qualified assistant staff. CONCLUSION: The level of training and the number of the nursing personnel influence hospital mortality and adverse outcomes; however, there are no evidence-based lower levels for nursing staff for inpatient care and perhaps this cannot be the case due to the changing complexity of the patients admitted, the comorbidities and possible treatment complications. There is a considerable need for research.

[The DIGG risk score : A risk predictive model of perioperative mortality after elective treatment of intact abdominal aortic aneurysms in the DIGG register]. / Der DIGG-Risikoscore : Ein Vorhersagemodell der perioperativen Sterblichkeit bei elektiver Versorgung des intakten Bauchaortenaneurysmas im DIGG-Register.

OBJECTIVE: The aim of the study was to develop a specific risk score for the aortic register of the German Institute for Vascular Health Care Research (DIGG) of the German Society for Vascular Surgery and Vascular Medicine (DGG) for the prediction of postoperative mortality in elective treatment of intact abdominal aortic aneurysms (iAAA). The score should also enable a risk-adjusted presentation of the register results in the near future. METHODS: The method of binary logistic regression analysis was used to calculate the model. The data from 10,404 patients were included in the analysis, of whom 7870 (75.6%) were treated by endovascular (EVAR) and 2534 (24.4%) by open (OR) aortic repair. It was examined which factors have an independent influence on hospital mortality and the effect size was determined as a score. RESULTS: For EVAR, the influencing factors with their effect sizes (score in brackets) were: age >85 years (2), female gender (2), juxtarenal AAA (5), maximum diameter >65 mm (2), diabetes mellitus (2), American Society of Anesthesiologists (ASA) score >3 (2), cardiac comorbidities (3) and renal insufficiency stage >3 (5). For OR the factors were: age >80 years (2), female gender (2), juxtarenal AAA (2), ASA score >3 (3), previous myocardial infarction (2), renal comorbidities (3) and previous stroke (2). The estimated hospital mortality was calculated for the individual case from the sum of the risk factors (scores). The accuracy of the model (correlation between observed and expected results) was determined using the receiver operating characteristic (ROC) curve. An area under the curve (AUC) of 0.817 (confidence interval 0.789-0.844) demonstrated an excellent discrimination. In a validation group of 3831 patients, the good agreement between observed and calculated results was confirmed. CONCLUSION: The DIGG risk score can predict risk-adjusted hospital mortality after EVAR and OR of iAAA in the DIGG register. Improvements with respect to the prediction are desirable for OR and should be strived for by extending the model in the future.

[Multimorbid vascular patients-do endovascular techniques expand the limits?] / Der multimorbide Gefäßpatient ­ erweitern endovaskuläre Techniken den Grenzbereich?

The answer to the question of whether endovascular techniques extend the barriers to treatment in multimorbid vascular patients depends on the localization of the vascular disease and its stage. In multimorbid vascular patients with limited life expectancy and asymptomatic carotid stenosis, neither an endovascular nor an open procedure is indicated but a conservative best medicinal treatment is to be preferred. In symptomatic carotid stenosis the endovascular procedure is indicated for special anatomical conditions, such as contralateral carotid artery occlusion, contralateral recurrent nerve palsy, recurrent stenosis following endarterectomy, radical neck dissection and radiotherapy in the cervical region. In the treatment of intact abdominal aortic aneurysms (AAA), endovascular procedures reduce the perioperative risk especially in older patients, allowing the indications for intervention in this group of patients to be expanded, provided that the life expectancy of such treated patients is still several years. There is no clear evidence as to whether endovascular repair should be preferred in ruptured AAAs but there are indications that with the establishment of EVAR the proportion of patients receiving treatment has increased in those patients who were previously denied surgery after arrival in hospital. In critical limb ischemia the propagation of endovascular techniques has not so much extended the indications for invasive therapy but instead the endovascular approach has superseded open bypass surgery, which is positively reflected in a lower perioperative morbidity, especially in older frail patients.

[The patient blood management concept : Joint recommendation of the German Society of Anaesthesiology and Intensive Care Medicine and the German Society of Surgery]. / Das Patient-Blood-Management-Konzept : Gemeinsame Empfehlung der Deutschen Gesellschaft für Anästhesiologie und Intensivmedizin und der Deutschen Gesellschaft für Chirurgie.

Patient blood management is a multimodal concept that aims to detect, prevent and treat anemia, optimize hemostasis, minimize iatrogenic blood loss, and support a patient-centered decision to provide optimal use of allogeneic blood products. Although the World Health Organization (WHO) has already recommended patient blood management as a new standard in 2010, many hospitals have not implemented it at all or only in part in clinical practice. The German Society of Anaesthesiology and Intensive Care Medicine and the German Society of Surgery therefore demand that i) all professionals involved in the treatment should implement important aspects of patient blood management considering local conditions, and ii) the structural, administrative and budgetary conditions should be created in the health care system to implement more intensively many of the measures in Germany.

The endovascular performance spectrum of vascular surgery departments in Germany: Results of an online survey among senior department physicians.

AIM: To survey the scope of vascular surgery services in Germany. METHOD: A total of 308 senior German vascular surgeons received a 19-point questionnaire pertaining to department structure and scope of services. Of these surgeons 223 replied between 16 August 2015 and 23 October 2015 (response rate 72 %), with 62.2 % reporting an additional qualification as an endovascular surgeon according to the guidelines of the German Society for Vascular Surgery and Vascular Medicine (Deutsche Gesellschaft für Gefäßchirurgie und Gefäßmedizin, DGG) and 43.5 % as a DGG® endovascular specialist. RESULTS: The number of respondents fully authorized to train in vascular surgery was 71.3 %, while 28.3 % were authorized for limited training. Authorization as a DGG® endovascular surgeon was reported by 24.2 % and authorization as a DGG® endovascular specialist by 17 % of respondents. All respondents performed endovascular interventions on pelvic vessels and 99.1 % also reported carrying out femoral and popliteal endovascular interventions. Endovascular procedures in crural vessels were carried out by 90.1 % and 93.7 % of vascular surgeons performed endovascular procedures in the region of the abdominal aorta (segment V), arteriovenous (AV) fistulas and shunts (85.2 %), upper extremity vessels (80.3 %), the thoracic aorta (segment III, 68.2 %), renal arteries (62.8 %) and visceral aorta (segment IV, 60.5 %). In all 43.5 % of respondents reported experience with endovascular procedures on the carotid bifurcation. Percutaneous arterial procedures formed the focus of endovascular activity, totalling on average 259 interventions per year and department, followed by diagnostic angiography (without intervention) at 166 procedures per year and hybrid arterial interventions at 141 interventions per year. CONCLUSION: This survey revealed a high level of endovascular expertise among vascular surgeons in Germany. This applies not only to the scope of endovascular activities in diagnosis and treatment but also to the number of estimated annual procedures.

[Patient blood management: Current state of the literature]. / Patient-blood-Management : Stand der aktuellen Literatur.

BACKGROUND: Preoperative anemia has a prevalence of approximately 30% and is one of the strongest predictors of perioperative red blood cell (RBC) transfusion. It is rarely treated although it is an independent risk factor for the occurrence of postoperative complications. Additionally, the high variability in the worldwide usage of RBC transfusions is alarming. Due to these serious deficits in patient care, in 2011 the World Health Organization recommended the implementation of a patient blood management (PBM). OBJECTIVES: This article provides information about PBM as a multidimensional and interdisciplinary approach. MATERIAL AND METHODS: A selective literature search was carried out in the Medline and Cochrane library databases including consideration of national and international guidelines. RESULTS: A PBM promotes the medically and ethically appropriate use of all available resources, techniques and materials in favor of an optimized perioperative patient care. Patients' own resources should be specifically protected, strengthened and used and include (i) diagnosis and therapy of preoperative anemia, (ii) minimizing perioperative blood loss, (iii) blood-conserving surgical techniques, (iv) restriction of diagnostic blood sampling, (v) utilization of individual anemia tolerance, (vi) optimal coagulation and hemotherapy concepts and (vii) guideline-based, rational indications for the use of RBC transfusions. CONCLUSION: A PBM should be advocated as an incentive to evaluate and critically optimize local conditions. An individual, interdisciplinarily structured bundle of different PBM measures has great potential to optimize the quality of patient care and to make it safer.

High Resolution Strain Analysis Comparing Aorta and Abdominal Aortic Aneurysm with Real Time Three Dimensional Speckle Tracking Ultrasound.

OBJECTIVE/BACKGROUND: Ultrasound measurement of aortic diameter for aneurysm screening allows supervision of aneurysm growth. Additional biomechanical analysis of wall motion and aneurysm deformation can supply information about individual elastic properties and the pathological state of the aortic wall. Local aortic wall motion was analyzed through imaged aortic segments according to age and pathology. METHODS: Sixty-five patients were examined with a commercial four dimensional ultrasound system (4D-US). Three groups were defined: patients with normal aortic diameter and younger than 60 years of age (n = 21); those with normal aortic diameter and older than 60 years of age (n = 25); and those with infrarenal aortic aneurysm (n = 19). A diastolic reference shape of aortic wall segments was obtained and local and temporally resolved wall strain was determined. Indices characterizing the resulting wall strain distribution were determined. RESULTS: The analysis of biomechanical properties displayed increasing heterogeneous and dyssynchronous circumferential strain with increasing patient age. Young patients exhibited higher mean strain amplitude. The distribution of the spatial heterogeneity index and local strain ratio was inversely proportional to age. The maximum local strain amplitude was significantly higher in the young (0.26 ± 0.17) compared with the old (0.16 ± 0.07) or aneurysmal aorta (0.16 ± 0.10). Temporal dyssynchrony significantly differed between young (0.13 ± 0.10) and old (aneurysmal 0.31 ± 0.04, non-aneurysmal 0.29 ± 0.05), regardless of aortic diameter. The spatial heterogeneity index and local strain ratio differentiate non-aneurysmal and aneurysmal aorta, regardless of age. CONCLUSIONS: 4D-US strain imaging enables description of individual wall motion (kinematics) of the infrarenal aorta with high spatial and temporal resolution. Functional differences between young, old, and aneurysmal aorta can be described by mean (circumferential) strain amplitude, the spatial heterogeneity index, and the local strain ratio. Further investigation is required to refine this new perspective of patient individualized characterization of the pathological AAA wall and eventually to rupture risk stratification.

Advanced 3D-Sonographic Imaging as a Precise Technique to Evaluate Tumor Volume.

Determination of tumor volume in subcutaneously inoculated xenograft models is a standard procedure for clinical and preclinical evaluation of tumor response to treatment. Practitioners frequently use a hands-on caliper method in conjunction with a simplified formula to assess tumor volume. Non-invasive and more precise techniques as investigation by MR or (µ)CT exist but come with various adverse effects in terms of radiation, complex setup or elevated cost of investigations. Therefore, we propose an advanced three-dimensional sonographic imaging technique to determine small tumor volumes in xenografts with high precision and minimized observer variability. We present a study on xenograft carcinoma tumors from which volumes and shapes were calculated with the standard caliper method as well as with a clinically available three-dimensional ultrasound scanner and subsequent processing software. Statistical analysis reveals the suitability of this non-invasive approach for the purpose of a quick and precise calculation of tumor volume in small rodents.

Hybrid approach to emergent and urgent treatment of complex thoracoabdominal aortic pathology.

OBJECTIVES: The aim was to report a single center experience with hybrid procedures in the emergency treatment of patients with thoracoabdominal aortic pathology. Thoracoabdominal aortic aneurysm (TAAA) repair is primarily conducted by conventional surgery in the urgent and emergency setting. The role of hybrid procedures with stent graft coverage of the aorta and extra-anatomical debranching of the renovisceral arteries has so far not been defined in this context. METHODS: From 2007 to 2013 30 patients (21 males, 9 females) undergoing an emergent or urgent TAAA hybrid procedure were included in a data register. The mean aneurysm diameter was 72 mm. Etiology was atherosclerosis in 23 patients (76.7%) and aortic dissection in seven patients (23.3%). Nineteen patients (63.3%) required emergency surgery. In 11 cases (36.7%), surgery was indicated for symptomatic aneurysms. Mean follow-up was 16 months (range 1-72 months). RESULTS: The hybrid procedure was completed in all patients. Renovisceral revascularization was performed with a total of 101 grafts (25 to the celiac, 30 to the superior mesenteric, 25 to the right renal, and 21 to the left renal artery). The 30-day and 1-year primary graft patency was 97.3% and 95.3% respectively. A median of three stent grafts per patient was deployed. One patient underwent surgical intervention for early endoleak (3.3%). Three patients (10%) developed spinal ischemia with persistent paraplegia. Two patients (6.7%) required chronic hemodialysis. Thirty-day mortality reached 26.7% (N = 8), being 36.8% in emergency patients (7 of 19) and 9.1% in the urgent group (1 of 11 patients). The cumulative postoperative survival rate after 12 months was 57.8%. CONCLUSIONS: Hybrid procedures have the potential to be an alternative treatment option for complex thoracoabdominal pathology in the urgent and emergency setting. The procedure is readily available and enables adequate surgical repair with enduring results. Nevertheless it is still associated with significant mortality and morbidity.

[Routine subclavian revascularisation employing regional anaesthesia]. / Routinemäßige Subclavia-Revaskularisation in Regionalanästhesie.

INTRODUCTION: The increasing incidence of endovascular surgery on the thoracic aorta (TEVAR) is leading to an increased rate of subclavian-carotid transposition (SCT). Intentional overstenting of the left subclavian artery extends the proximal landing zone. If overstenting leads to a subclavian steal syndrome, vertebrobasilar insufficiency or if the risk of spinal ischaemia is present, SCT can safely be carried out with regional anaesthesia by means of a cervical block. MATERIALS AND METHODS: Since January 2010 regional anaesthesia was employed in 13 consecutive patients receiving an SCT in our clinic. Subclavian revascularisation was performed either as adjunct procedure for TEVAR or in patients with occlusive disease of the aortic arch. The clinical course was prospectively observed. RESULTS: In 62 % of the cases (n = 8) a transposition of the subclavian artery onto the common carotid artery was carried out. In 38 % of the cases (n = 5) an intraoperative decision was made to construct a carotid-subclavian bypass. In 30 % (n = 4) of the cases a conversion from cervical block to general anaesthesia was necessary. All reconstructions proved to be patent at follow-up. CONCLUSION: Subclavian-carotid transposition under regional anaesthesia is safe and technically feasible if occlusion of the subclavian artery by thoracic stentgraft or stenosis has occurred. The technique employing regional anaesthesia can, therefore, also be offered to patients with increased risk for complications due to general anaesthesia.

Strain measurement of abdominal aortic aneurysm with real-time 3D ultrasound speckle tracking.

OBJECTIVES: Abdominal aortic aneurysm rupture is caused by mechanical vascular tissue failure. Although mechanical properties within the aneurysm vary, currently available ultrasound methods assess only one cross-sectional segment of the aorta. This study aims to establish real-time 3-dimensional (3D) speckle tracking ultrasound to explore local displacement and strain parameters of the whole abdominal aortic aneurysm. MATERIALS AND METHODS: Validation was performed on a silicone aneurysm model, perfused in a pulsatile artificial circulatory system. Wall motion of the silicone model was measured simultaneously with a commercial real-time 3D speckle tracking ultrasound system and either with laser-scan micrometry or with video photogrammetry. After validation, 3D ultrasound data were collected from abdominal aortic aneurysms of five patients and displacement and strain parameters were analysed. RESULTS: Displacement parameters measured in vitro by 3D ultrasound and laser scan micrometer or video analysis were significantly correlated at pulse pressures between 40 and 80 mmHg. Strong local differences in displacement and strain were identified within the aortic aneurysms of patients. CONCLUSION: Local wall strain of the whole abdominal aortic aneurysm can be analysed in vivo with real-time 3D ultrasound speckle tracking imaging, offering the prospect of individual non-invasive rupture risk analysis of abdominal aortic aneurysms.

The temporal and spatial distribution of macrophage subpopulations during arteriogenesis.

Chronic arterial occlusion leads to growth of collaterals - a process termed arteriogenesis, in which macrophages play a prominent role in remodelling and growth. However, a detailed analysis which of distinct macrophage subpopulations involved in arteriogenesis has never been performed. In the present study the temporal and spatial distribution of macrophage subtypes during arteriogenesis in a rat model with chronically elevated fluid shear stress (FSS) is investigated. Local macrophage subpopulations were histologically immuno-phenotyped using CD68 (a ubiquitous macrophage marker) and CD163, a specific M2 macrophage marker. Without occlusion few M2-macrophages reside in the perivascular space. Early after occlusion (12h) the number of M2 macrophages increases strongly and M1 macrophages begin emerging into the collateral. After 3 days they appear in the perivascular space. Both macrophage subtypes increase until 28d after treatment, whereas M2 macrophages dominate at the site of collateral growth. The local distribution of the subpopulations changes during the arteriogenic process. Whereas M1 macrophages are detected directly adjacent to the media, M2 macrophages are present in the most outer perivascular region of the growing collateral vessel. Systemic alterations of blood leucocytes in mice after femoral artery ligature (FAL) were investigated by FACS analysis of serial blood samples. During collateral remodelling histological changes were not reflected in circulating monocytes in the peripheral blood. The activation state of macrophages in mice with FAL was modulated by injections of either dexamethasone or the interleukins IL10 or IL3/IL14. The arteriogenic response was assessed by hind limb perfusion with laser Doppler measurements after 3, 7 and 14d. Suppressing inflammatory monocyte subtypes (M1) with dexamethasone led to impaired perfusion recovery after FAL in mice, whereas IL10 or IL4/IL13 application significantly increased perfusion recovery. This investigation demonstrates that a forced shift towards M2 macrophages improves the arteriogenic response. The distinct early increase and spatial distribution of M2 macrophages support the idea that this subtype plays a predominant role during collateral remodelling.

[Placement of a native arteriovenous access]. / Anlage nativer arteriovenöser Zugänge.

The epidemically increasing number of diabetics is resulting in an increasing number of patients with end-stage renal failure who, furthermore, show a high degree of co-morbidity. An increasingly longer survival time with dialysis also means that the group of patients requiring functional dialysis access is continuously growing. The autologous arteriovenous fistula with its high function and low complication rate is the best access form, and should be provided to as many of those patients requiring dialysis as possible. This article discusses the timing of dialysis access, the importance of the medical history and the physical examination, preoperative investigation of the prospective fistula vein, the possibilities of anastomosis, maturation of the fistula and long-term results.

Cerebral arteriogenesis is enhanced by pharmacological as well as fluid-shear-stress activation of the Trpv4 calcium channel.

OBJECTIVES: This study aimed to determine the importance of the shear-stress-sensitive calcium channels Trpc1, Trpm7, Trpp2, Trpv2 (transient receptor potential cation channel, subfamily V, member 2) and Trpv4 for cerebral arteriogenesis. The expression profiles were analysed, comparing the stimulation of collateral growth by target-specific drugs to that achieved by maximum increased fluid shear stress (FSS). DESIGN: A prospective, controlled study wherein rats were subjected to bilateral carotid artery ligature (BCL), or BCL + arteriovenous fistula, or BCL + drug application. METHODS: Messenger RNA (mRNA) abundance and protein expression were determined in FSS-stimulated cerebral collaterals by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. Drugs were applied via osmotic mini pumps and arteriogenesis was evaluated by post-mortem angiograms and Ki67 immunostaining. RESULTS: Trpv4 was the only mechanosensitive Trp channel showing significantly increased mRNA abundance and protein expression after FSS stimulation. Activation of Trpv4 by 4α-phorbol-12,13-didecanoate caused significantly enhanced collateral growth (length: 4.43 ± 0.20 mm and diameter: 282.6 ± 8.1 µm) compared with control (length: 3.80 ± 0.06 mm and diameter: 237.3 ± 5.3 µm). Drug application stimulated arteriogenesis to almost the same extent as did maximum FSS stimulation (length: 4.61 ± 0.07 mm and diameter: 327.4 ± 12.6 µm). CONCLUSIONS: Trpv4 showed significantly increased expression in FSS-stimulated cerebral collaterals. Pharmacological Trpv4 activation enhanced cerebral arteriogenesis, pinpointing Trpv4 as a possible candidate for the development of new therapeutic concepts.