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Fluid-solid interaction is a primary feature of cardiovascular flows. There is increasing interest in the numerical solution of these systems as the extensive computational resource required for such studies becomes available. One form of coupling is an external weak coupling of separate solid and fluid mechanics codes. Information about the stress tensor and displacement vector at the wetted boundary is passed between the codes, and an iterative scheme is employed to move towards convergence of these parameters at each time step. This approach has the attraction that separate codes with the most extensive functionality for each of the separate phases can be selected, which might be important in the context of the complex rheology and contact mechanics that often feature in cardiovascular systems. Penrose and Staples describe a weak coupling of CFX for computational fluid mechanics to ANSYS for solid mechanics, based on a simple Jacobi iteration scheme. It is important to validate the coupled numerical solutions. An extensive analytical study of flow in elastic-walled tubes was carried out by Womersley in the late 1950s. This paper describes the performance of the coupling software for the straight elastic-walled tube, and compares the results with Womersley's analytical solutions. It also presents preliminary results demonstrating the application of the coupled software in the context of a stented vessel. [ABSTRACT FROM AUTHOR]

Background and Objective:Health equity is playing an increasing role in British government health policy. Evidence of social deprivation affecting outcomes in surgery is poor. This study aimed to assess the influence of social deprivation on the outcome of major arterial surgery.Materials and Methods:A retrospective cohort study was undertaken in patients undergoing elective or emergency open surgery for abdominal aortic aneurysms or lower limb arterial reconstruction over an eight and a half year period within one institution. Patient deprivation was calculated for each patient with the Index of Multiple Deprivation (IMD) score. This was then entered into multivariate models to determine its effect on mortality and postoperative length of stay after adjustment for confounders.Results:Five hundred and six patients were included in the study. There were 45 deaths (8.9%) and median (IQR) postoperative length of stay was 8 (4–15) days. The median (IQR) IMD score was 46.4 (28.3–64.5). IMD score correlated with ASA grade and was significantly higher in smokers, patients with respiratory disease and those with left ventricular failure. IMD (OR = 1.01; 95% CI = 0.99-1.03;p= .45) did not affected mortality, which was associated with aortic surgery, emergency surgery, and high ASA grade. Postoperative length of stay, which was longer with/after aortic surgery, tissue loss, emergency surgery, high ASA grade, low haemoglobin, and age over 80 years was also independent of deprivation (Spearman's rho = −0.49,p= .28).Discussion: No effect of social deprivation on mortality or length of stay in patients undergoing major arterial surgery was identified. [ABSTRACT FROM PUBLISHER]

The purpose of this study was to compare the feasibility, blood loss, duration of surgery and complications between patients in whom both uterine arteries were ligated by surgical clips and cut using a 5-mm ligature at the beginning of total laparoscopic hysterectomy (TLH) and patients in whom uterine arteries were not ligated at the beginning of TLH. In our prospective study, a total of 60 women underwent TLH. Uterine artery ligation (UAL) was done at the beginning of the procedure. Women were divided into TLH + UAL (n = 30) and TLH (n = 30) groups. In TLH group, TLH was done without ligating the uterine arteries at the beginning of the procedure. In TLH + UAL group, TLH was done with ligation of both uterine arteries at the beginning of the procedure. The mean operating time was longer for the TLH group (99.16 ± 7.01) than TLH + UAL group (63.27 ± 7.16). The median total blood loss was higher in TLH group (109.38 ± 33.03 mL) than TLH + UAL group (47.50 ± 8.12 mL). UAL at the beginning of TLH is a technically feasible procedure. It reduces the total blood loss and decreases the time taken for the procedure and length of hospital stay. [ABSTRACT FROM AUTHOR]

The orbital branch of the infraorbital artery, a key vascular structure that is not universally noted in orbital textbooks and atlases, is clinically significant, since injury to it can result in perioperative hemorrhage. We conducted a cadaver dissection to document its presence, measure its location, and evaluate it histopathologically. It was present in 8 of 9 orbits and was a mean distance of 16.6 mm (range 10-23) from the inferior orbital rim. In half of the specimens, there were 2 separate structures seen. Histopathology confirmed these structures to be neurovascular bundles. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the study was to evaluate the prevalence of acute kidney injury (AKI) in a cohort of surgically treated patients with peripheral artery disease (PAD) and its association with the short-term and long-term outcome. Materials and methods: We conducted a retrospective cohort study on all the consecutive PAD inpatients in 2008. Data on the patients' demographic characteristics, medical history, treatment, outcome and laboratory tests measurements were retrieved from the medical records. Results: We analyzed 166 patients (71.6% males, mean age 63.2 years ± SD 10.7 years) and found an AKI prevalence of 12.7%. The AKI patients' group had more chronic kidney disease (CKD) (23.8% vs. 6.2%, p = 0.005), diabetes mellitus (DM) (61.9% vs. 33.1%, p = 0.011) and a higher length of hospital stay (19.48 vs. 15.42 days, p = 0.047). At one year, the mortality was 33.3% in the AKI group compared to 1.3% in non-AKI group, with a strong association between AKI and death (OR = 35.7; 95%CI = 6.7 to 189) and AKI and major cardiovascular events (OR = 29.1; 95% CI = 6.8 to 123.4). There was no significant difference in terms of age, cardiovascular disease and medication between the two groups. Conclusions: AKI was associated with a poorer one-year outcome after the surgery of PAD patients. In our study, the presence of previous chronic kidney disease and type 2 diabetes increased the incidence of acute kidney injury after surgery. [ABSTRACT FROM AUTHOR]

Background and aim: We investigated the clinical outcome of early initiated peritoneal dialysis (PD) use in our newborn patients who underwent arterial switch operation (ASO) for transposition of the great arteries (TGA) and had routine intraoperative PD catheter implantation. We determined the risk factors for PD, factors associated with prolonged PD, morbidity, and mortality. The aim of the present study was to describe our experience of using PD in this patient cohort. Materials and Methods: Eighty two patients who were diagnosed with TGA and TGA-ventricular septal defect (VSD) and who had undergone TGA correction operation in Başkent University, Istanbul Medical Research and Training Hospital between 2007 and 2012 were retrospectively investigated. All the patients were under 30 days old. PD catheters were routinely implanted intraoperatively at the end of the operation. PD was initiated in transient renal insufficiency. In the absence of oliguria and increased creatinine level, PD was established in the presence of one of the following: clinical signs of fluid overload, hyperkalemia (>5 mEq/L), persistent metabolic acidosis, lactate level above 8 mmol/L or low cardiac output syndrome. The patients were divided into two groups according to the need for postoperative PD (PD group and non-PD group). PD was initiated in 32 (39%) patients after the operation, whereas 50 (61%) patients did not need dialysis. The clinical outcomes and perioperative data of the two groups were compared. Results: The demographics in the two groups were similar. Cardiopulmonary bypass time was longer in the PD group [non-PD group, 175.24 ± 32.39 min; PD group, 196.22 ± 44.04 min ( p <  0.05)]. Coronary anomaly was found to be higher in the PD group [non-PD group, n = 2 patients (4.0%); PD group, n = 7 patients (21.9%); p <  0.05]. There was more need for PD in TGA + VSD patients [simple TGA patients, n = 14; TGA + VSD patients, n = 18 ( p <  0.05)]. PD rate was higher in patients whose sterna were left open at the end of the operation ( p <  0.05). The ventilator time [non-PD group, 4.04 ± 1.51 days; PD group, 8.12 ± 5.21 days ( p <  0.01)], intensive care unit stay time [non-PD group, 7.98 ± 5.80 days; PD group, 15.93 ± 18.31 days ( p <  0.01)], and hospital stay time were significantly longer in the PD group [non-PD group, 14.98 ± 10.14 days; PD group, 22.84 ± 20.87 days ( p <  0.01)]. Conclusion: We advocate routine implantation of PD catheters to patients with TGA-VSD, coronary artery anomaly, and open sternum in which we have determined high rate of postoperative PD need. [ABSTRACT FROM AUTHOR]

Managing asymptomatic carotid atherosclerosis with a view to preventing ischemic stroke is a challenging task. As the annual risk of stroke in untreated asymptomatic patients on average is less than the risk of surgical intervention, the key question is how to identify those asymptomatic individuals whose risk of stroke is elevated and who would benefit from surgery, while sparing low-risk asymptomatic patients from the risks of surgical intervention. The advent of a multitude of noninvasive carotid imaging techniques offers an opportunity to improve risk stratification in patients and to monitor the response to medical therapies; assessing efficacy at individual and population levels. As part of this, plaque measurement techniques (using ultrasound, computed tomography or MRI) may be employed in monitoring plaque/component regression and progression. Novel imaging applications targeted to plaque characteristics, inflammation and neovascularization, including contrast-enhanced ultrasound and MRI, dynamic contrast-enhanced MRI, and fluorodeoxyglucose-PET, are also being explored. Ultimately, noninvasive imaging and other advances in risk stratification aim to improve and individualize the management of patients with carotid atherosclerosis. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to verify whether preoperative diabetes, hypertension, and renal function had any relationship with postoperative tubule function in patients submitted to anesthesia for arterial surgery. Methods: Prospective observational study. One hundred and forty-four patients submitted to anesthesia for arterial surgery enrolled consecutively and divided into four groups: G1 - diabetes and hypertension; G2 - diabetes; G3 - hypertension; and G4 - without hypertension or diabetes. Urine was obtained for laboratory analysis of urinary creatinine (Ucr), alkaline phosphatase (AP), γ-glutamyltransferase (γGT), and blood for cystatin C and creatinine before the surgery (M1) and 24 h after the surgery (M2). Results: Values of γGT, γGT/Ucr, and AP × γGT/Ucr increased at M2 in G4. Patients without renal function compromise (GFR ≥90 mL/min/1.73 m2) presented increased γGT/Ucr and AP × γGT/Ucr values at M2 and those with slightly compromised renal function (60-89 mL/min/1.73 m2) presented increased γGT values at M2. There was no correlation between deltaCystatin C and deltaAP, deltaγGT, deltaγGT/Ucr, deltaAP/Ucr, and deltaAP × γGT/Ucr. Conclusions: Diabetes, hypertension, and preoperative renal function seem to interfere in tubular enzymuria immediately after surgery in arteriopathic patients. However, when these markers do not increase in postoperative period, renal dysfunction cannot be discarded. [ABSTRACT FROM AUTHOR]

Conclusion: Endoscopic cauterization of the sphenopalatine artery and anterior ethmoid artery is a first-line standard of care in managing intractable epistaxis, after the failure of previous packing. Epistaxis occurs in 12% of the population. Treatment is often based on nasal packing that could be poorly effective in the treatment of severe posterior epistaxis. Objective: To evaluate the effectiveness of the endoscopic approach for posterior epistaxis. Methods: We report the experience of endoscopic cauterization in two metropolitan hospitals in Italy: 48 patients with at least one nasal packing in the 3 weeks before hospital admission. They underwent endoscopic cauterization of the sphenopalatine artery or of the anterior ethmoid artery. Results: The patients' mean age was 58.7 years; the mean hospital stay was 2.97 days. In 42 cases (87.5%), cauterization of the sphenopalatine artery was performed, and 6 (12.5%) were subjected to anterior ethmoid artery treatment. Epistaxis control was achieved in 93% of cases; 3 patients had a recurrent nasal bleeding, and were treated with anterior nasal packing. Minor complications occurred in 27.1%. We achieved a shorter hospital stay compared with patients who underwent anteroposterior packing. [ABSTRACT FROM AUTHOR]

Atherosclerotic disease of the carotid arteries has been identified as a major cause of stroke and thromboembolism from ruptured atheroma plaques within the walls of these vessels, has been proposed as the putative pathophysiological event underlying cerebral ischaemia. Carotid endarterectomy has been shown to be superior to pharmacotherapy in reducing the likelihood of further disabling stroke or death, in selected individuals. It is, therefore, necessary to identify those individuals at highest risk of stroke, for whom the risks of aggressive intervention may be worthwhile. Our understanding of atherosclerosis suggests that plaque rupture is precipitated by inflammation that causes alteration in the morphological composition and functional activity within the plaque resulting in exposure of thrombogenic material to the circulation. Identification of this in vivo biological process or surrogate markers suggesting 'vulnerability' to plaque rupture could, therefore, aid the selection of individuals for whom the risks of aggressive intervention may be warranted. This review outlines the imaging modalities that have been evaluated for in vivo structural assessment of carotid plaques and risk stratification for selection for aggressive interventions. More recent strategies appear to be moving toward a combination of morphological and functional imaging in order to visualize the pathophysiological mechanisms that underlie plaque rupture. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 36-year-old woman with her second pregnancy who was presented to the hospital due to hemodynamic instability following a peripartum hysterectomy and ligation of the bilateral hypograstric artery. Topics mention including the computed tomography angiography result, performing of an emergency caesarian and recanalisation of right gonadal artery was observed.