The successful use of polylactide wound dressings for chronic lower leg wounds: A retrospective analysis.

Chronic wounds are a challenging medical entity for patients, medical professionals and healthcare systems. Frequently, patients present themselves to wound specialists after months or even years of unsuccessful treatment. Recent developments have resulted in a multitude of different advanced wound dressings created to treat complex, chronic wounds, one of which is the polylactide dressing Suprathel. This study aimed at investigating the healing potential of Suprathel in chronic wounds and differentiating between old and "young", diabetic and non-diabetic chronic wounds. A prospective, multicentric, non-controlled intervention study was conducted, treating patients with chronic lower leg ulcers (>3 months) with Suprathel and assessing them weekly. Afterwards, a retrospective analysis was performed analysing the wound size initially, after 4 and after 8 weeks of treatment. Furthermore, a differentiation between diabetic and non-diabetic, and chronic wounds older and younger than 12 months, was assessed. A significant reduction in wound size was observed in the study population after 8 weeks of treatment. The effect size in the diabetic wound and the old chronic wound group even reached more than one, with the other groups still showing a large effect of the intervention. This study shows that Suprathel is a valuable tool in the armamentarium of a wound specialist. Not only could we show a positive effect on chronic wounds, we could even demonstrate a significant wound size reduction in chronic wounds of old and young, as well as diabetic wounds, with the treatment of older chronic and diabetic wounds yielding an even larger effect size. Further randomised, controlled studies are necessary to show the full potential of advanced wound dressing materials in large patient cohorts.

Assessing changes in tissue oxygenation by near-infrared spectroscopy following brachial plexus block for arteriovenous fistula surgery: A prospective observational pilot study.

BACKGROUND: Near-infrared spectroscopy (NIRS) can be used to measure tissue oxygen saturation (StO2) in different sites and in a wide range of clinical scenarios. Peripheral regional anaesthesia induces vascular changes causing increased arterial blood flow and venodilatation, but its effect on StO2 is still under debate. This is especially so for patients undergoing arteriovenous fistula surgery, wherein latest data suggest an improved outcome under brachial plexus block (BPB) compared with local anaesthesia, but no data are available. OBJECTIVE: The aim of this study was to investigate changes in StO2 following BPB prior to arteriovenous fistula surgery using NIRS. DESIGN: A prospective observational study. SETTING: A secondary teaching hospital from August 2016 to March 2017. PATIENTS: Fifteen patients undergoing arteriovenous fistula surgery. INTERVENTION: Ultrasound-guided BPB in 15 patients undergoing arteriovenous fistula surgery. OUTCOME MEASURES: StO2 at baseline and compared with baseline and the contralateral arm following BPB measured using NIRS of the thenar eminence (NIRSth). RESULTS: Baseline values of StO2 assessed by NIRSth were 42.6 ±â€Š7.7% in the arteriovenous fistula arm and 42.7 ±â€Š9.7% in the contralateral arm. There was no significant difference between the two. Five minutes after BPB, there was a significant increase in StO2 of the blocked arm, compared with the control arm expressed as difference of absolute values (7.1 ±â€Š9.7%). At 60 min, an absolute difference of 21.0 ±â€Š13.5% was reached. The absolute increase in StO2 of the blocked arm compared with baseline reached significance after 5 min (8.8 ±â€Š4.6%) and increased up to 23.2 ±â€Š8.2% after 60 min. CONCLUSION: NIRSth indicates that BPB significantly increases StO2 of the arteriovenous fistula arm in patients undergoing haemodialysis. TRIAL REGISTRATION: Clinicaltrials.gov: NCT03044496.

Rationale, scope, and 20-year experience of vascular surgical training with lifelike pulsatile flow models.

Vascular surgical training currently has to cope with various challenges, including restrictions on work hours, significant reduction of open surgical training cases in many countries, an increasing diversity of open and endovascular procedures, and distinct expectations by trainees. Even more important, patients and the public no longer accept a "learning by doing" training philosophy that leaves the learning curve on the patient's side. The Vascular International (VI) Foundation and School aims to overcome these obstacles by training conventional vascular and endovascular techniques before they are applied on patients. To achieve largely realistic training conditions, lifelike pulsatile models with exchangeable synthetic arterial inlays were created to practice carotid endarterectomy and patch plasty, open abdominal aortic aneurysm surgery, and peripheral bypass surgery, as well as for endovascular procedures, including endovascular aneurysm repair, thoracic endovascular aortic repair, peripheral balloon dilatation, and stenting. All models are equipped with a small pressure pump inside to create pulsatile flow conditions with variable peak pressures of ~90 mm Hg. The VI course schedule consists of a series of 2-hour modules teaching different open or endovascular procedures step-by-step in a standardized fashion. Trainees practice in pairs with continuous supervision and intensive advice provided by highly experienced vascular surgical trainers (trainer-to-trainee ratio is 1:4). Several evaluations of these courses show that tutor-assisted training on lifelike models in an educational-centered and motivated environment is associated with a significant increase of general and specific vascular surgical technical competence within a short period of time. Future studies should evaluate whether these benefits positively influence the future learning curve of vascular surgical trainees and clarify to what extent sophisticated models are useful to assess the level of technical skills of vascular surgical residents at national or international board examinations. This article gives an overview of our experiences of >20 years of practical training of beginners and advanced vascular surgeons using lifelike pulsatile vascular surgical training models.

Simulator training on pulsatile vascular models significantly improves surgical skills and the quality of carotid patch plasty.

OBJECTIVE: Vascular surgeons perform numerous highly sophisticated and delicate procedures. Due to restrictions in training time and the advent of endovascular techniques, new concepts including alternative environments for training and assessment of surgical skills are required. Over the past decade, training on simulators and synthetic models has become more sophisticated and lifelike. This study was designed to evaluate the impact of a 3-day intense training course in open vascular surgery on both specific and global vascular surgical skills. METHODS: Prospective observational cohort analysis with various parameter measurements of both surgical skills and the technical quality of the finished product, performed before and after 3 days of simulator training of 10 participants (seven male and three female) in a vascular surgery training course. The simulator model used was a conventional carotid endarterectomy with a Dacron patch plasty on a lifelike carotid bench model under pulsatile pressure. The primary end points were assessment of any changes in the participants' surgical skills and in the technical quality of their completed carotid patches documented by procedure-based assessment forms. Scores ranging from 1 (inadequate) to 5 (excellent) were compared by a related-sample Wilcoxon signed test. Interobserver reliability was estimated by Cronbach's alpha (CA). RESULTS: A significant improvement in surgical skills tasks was observed (P < .001). The mean score increased significantly by 21.5% from fair (3.43 ± 0.93) to satisfactory (4.17 ± 0.69; P < .001). The mean score for the quality of the carotid patch increased significantly by 0.96 (27%) from fair (3.55 ± 0.87) to satisfactory (4.51 ± 0.76; P < .01). The median interassessor reliability for the quality of the carotid patch was acceptable (CA = 0.713) and for surgical skills was low (CA = 0.424). CONCLUSIONS: This study shows that lifelike simulation featuring pulsatile flow can increase surgical skills and technical quality in a highly sophisticated multistep vascular intervention. This training provides comparatively inexpensive and lifelike training possibilities for the adoption and assessment of surgical skills required to perform delicate vascular surgical procedures.

Fatal Clostridium septicum infection in a patient with non-Hodgkin's lymphoma undergoing multimodal oncologic therapy.

BACKGROUND: Clostridium septicum infections are rare but often fatal. They are known to be associated with a compromised immune system, e.g. with hematologic malignancies. CASE REPORT: We report on a spontaneous, non-traumatic C. septicum infection in a patient with non-Hodgkin's lymphoma undergoing irradiation due to abdominal bulk. Irradiation was delivered in daily fractions of 1.8 Gy. After 7 fractions, the patient suddenly developed severe pain in the lower leg. Clinical examination showed no pathological findings. However, a rapid progression of symptoms with motoric and sensoric deficits progressed rapidly within hours. Sizzling noise and gas entrainment were detectable about 9 h after the first symptoms. Despite immediate surgical treatment, and in the end amputation, the patient died 14 h later of septic shock. Histopathology showed gas gangrene in the leg tissue, with hemorrhagic muscular necrosis and enclosed gas vesicles. C. septicum was identified as causative organism. CONCLUSIONS: Irradiation as well as chemotherapy may have enhanced the risk by immunosuppression and induction of mucosal damage. Earlier antibiotic treatment might have slowed down the clinical course and thus given more time for correct diagnosis and treatment.

Intentional overstenting of the celiac trunk during thoracic endovascular aortic repair: preoperative role of multislice CT angiography.

PURPOSE: To report initial experience with intentional coverage of the celiac trunk to expand the distal landing zone in thoracic endovascular aortic repair (TEVAR) and to analyze preprocedural visualization of collateral blood flow by noninvasive computed tomographic angiography (CTA). METHODS: Between January 1997 and April 2008, 202 patients with thoracic aortic pathologies were treated by TEVAR. In 5 high-risk patients (3 women; mean age 73 years, range 62-88), intentional overstenting of the celiac trunk was performed when treating 2 ruptured aneurysms, 1 penetrating aortic ulcer, 1 type B dissection, and 1 distal type I endoleak. Multislice CTA (MSCTA) with multiplanar reconstruction was used to visualize the visceral collaterals; no angiography was performed. RESULTS: MSCTA was able to visualize the patent pancreaticoduodenal artery and other collaterals and to verify sufficient collateral blood flow. All celiac arteries were patent preoperatively; only 1 severe stenosis was demonstrated. After successful TEVAR in all cases, 1 of the 5 patients developed visceral malperfusion and died of multiorgan failure 1 day after TEVAR of a ruptured thoracic aneurysm. A second patient died 6 weeks postoperatively due to cardiopulmonary failure (non-procedure-related). There were no late complications or reinterventions. CONCLUSION: Overstenting of the celiac trunk is feasible, with acceptable risk in emergency cases and high-risk patients if MSCTA documents collateral blood flow. Noninvasive MSCTA is sufficient and may obviate pre- and intraoperative selective angiography with or without a balloon occlusion test.

Hybrid procedures for thoracoabdominal aortic aneurysms and chronic aortic dissections - a single center experience in 28 patients.

OBJECTIVE: We report our 6-year experience with the visceral hybrid procedure for high-risk patients with thoracoabdominal aortic aneurysms (TAAA) and chronic expanding aortic dissections (CEAD). METHODS: Hybrid procedure includes debranching of the visceral and renal arteries followed by endovascular exclusion of the aneurysm. A series of 28 patients (20 male, mean age 66 years) were treated between January 2001 and July 2007. Sixteen patients had TAAAs type I-III, one type IV, four thoracoabdominal placque ruptures, and seven patients CEAD. Patients were treated for asymptomatic, symptomatic, and ruptured aortic pathologies in 20, and 4 patients, respectively. Two patients had Marfan's syndrome; 61% had previous infrarenal aortic surgery. The infrarenal aorta was the distal landing zone in 70%. In elective cases, simultaneous approach (n = 9, group I) and staged approach (n = 11, group II) were performed. Mean follow-up is 22 months (range 0.1-78). RESULTS: Primary technical success was achieved in 89%. All stent grafts were implanted in the entire thoracoabdominal aorta. Additionally, three patients had previous complete arch vessel revascularization. Left subclavian artery was intentionally covered in three patients (11%). Thirty-day mortality rate was 14.3% (4/28). One patient had a rupture before the staged endovascular procedure and died. Overall survival rate at 3 years was 70%, in group I 80%, and in group II 60% (P = .234). Type I endoleak rate was 8%. Permanent paraplegia rate was 11%. Three patients required long-term dialysis (11%). Peripheral graft occlusion rate was 11% at 30 days. Gut infarction with consecutive bowel resection occurred in two patients. There was no significant difference between group I and II regarding paraplegia and complications. CONCLUSIONS: Early results of visceral hybrid repair for high-risk patients with complex and extended TAAAs and CEADs are encouraging in a selected group of high risk patients in whom open repair is hazardous and branched endografts are not yet optional.

Hybrid procedures as a combined endovascular and open approach for pararenal and thoracoabdominal aortic pathologies.

OBJECTIVES: to report our experience with hybrid vascular procedures in patients with pararenal and thoracoabdominal aortic pathologies. METHODS: 68 patients were treated for thoracoabdominal aortic pathologies between October 1999 and February 2004; 19 patients (16 men; mean age 68, range 40-79) with high risk for open thoracoabdominal repair were considered to be candidates for combined endovascular and open repair. Aortic pathologies included five thoracoabdominal Crawford I aneurysms, one postdissection expanding aneurysm, three symptomatic plaque ruptures (Crawford IV), five combined thoracic descending and infrarenal aneurysms with a healthy visceral segment, three juxtarenal or para-anastomotic aneurysms, and two patients with simultaneous open aortic arch replacement and a rendezvous maneuver for thoracic endografting. Commercially available endografts were implanted with standardized endovascular techniques after revascularization of visceral and renal arteries. RESULTS: Technical success was 95%. One patient developed a proximal type I endoleak after chronic expanding type B dissection and currently is waiting conversion. Nine patients underwent elective, five emergency and five urgent (within 24 h) repair. 17 operations were performed simultaneously, and 2 as a staged procedure. Postoperative complications include two retroperitoneal hemorrhages, and one patient required long-term ventilation with preexisting subglottic tracheal stenosis. Thirty-day mortality was 17% (one multiple organ failure, one secondary rupture after open aortic arch repair, one myocardial infarction). Paraplegia or acute renal failure were not observed. Total survival rate was to 83% with a mean follow-up of 30 months. CONCLUSIONS: Midterm results of combined endovascular and open procedures in the thoracoabdominal aorta are encouraging in selected high risk patients. Staged interventions may reduce morbidity.

Impaired Fas-induced apoptosis of T lymphocytes in patients with abdominal aortic aneurysms.

OBJECTIVE: Homeostasis of the immune system is maintained by apoptotic elimination of potentially pathogenic autoreactive lymphocytes. Emerging evidence shows that Fas-mediated apoptosis is impaired in activated lymphocytes from patients with autoimmune disease. The aim of this work was to assess apoptosis mediated by the cell death receptor Fas in peripheral T lymphocytes from patients with abdominal aortic aneurysms (AAA). METHODS: The apoptotic pathway was triggered by anti-Fas monoclonal antibodies in cultured and activated peripheral T-cell lines from 20 AAA patients with control groups of 15 patients with aortic atherosclerotic occlusive disease (AOD) and 25 healthy individuals. Cell survival and death (apoptosis) rate were assessed. RESULTS: Cross-linkage of Fas receptor exerted a strong apoptotic response on T cells from AOD patients and healthy controls, but a much less pronounced effect on T cells from AAA patients. The evaluation of cell survival rate showed a significantly higher percentage in AAA group (98.9% +/- 10.3%) than in the AOD subjects (58.9% +/- 15.2%) or the healthy group (59.4% +/- 12.9%; P < .001). Apoptosis assessment by annexin V and propidium iodide staining and flow cytometry showed similar results. The defect in AAA group was not due to decreased Fas expression, since Fas was expressed at normal levels. Moreover, it specifically involved the Fas system because cell death was induced in the normal way by methylprednisolone. Complementary DNA sequencing identified no causal Fas gene mutation, but two silent single nucleotide polymorphisms with higher frequency were found in the AAA group. CONCLUSIONS: Fas-induced apoptosis in activated T cells from AAA patients is impaired. This may disturb the normal down-regulation of the immune response and thus provide a new insight into possible mechanisms and routes in the pathogenesis of AAA.