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Acute limb ischemia (ALI) is a serious medical emergency leading to high rate of complications, being not only limb- but even life-threatening, often despite early successful revascularization.1 Improvements in surgical techniques and perioperative patient care may have reduced the incidence of major complications in ALI patients over the years, but the results of trials published recently seem to document a persistent high risk, with reported 30-day amputation rate of 5% to 12%, mortality risk at 10% to 38%, combined incidence of amputation and death of 25% to 37.5%, at 1- to 6-month follow-up.2–7 Concomitant underlying diseases, the metabolic derangement that seems as a result of the acute insult, and a possible reperfusion injury following revascularization may account for this severe prognosis.8 Only anticoagulation, fasciotomy (when indicated), and perioperative supportive treatment are established strategies in ALI patients.1,8,9 Possible benefit from cardiovascular active therapies has recently been suggested in patients undergoing peripheral revascularization or noncardiac major surgical intervention.10,11 Moreover, several categories of compounds, potentially acting on pathobiological mechanisms of ischemia-reperfusion syndrome, have been tested in experimental models, but none of them has as yet been proven effective in clinical studies in patients with ALI.12–18 Because of their pharmacologic profile, prostanoids represent a potentially interesting category as adjuvant treatment of ALI patients.19 Several ischemia-reperfusion studies described the use of prostaglandins for reduction of postischemic tissue injuries, and even recently both PGE1 and PGI2 appeared as potent inhibitors of reflow-paradox in a preclinical model of reperfusion injury.20 Iloprost is a widely studied synthetic analogue of prostacyclin, with a 10-fold higher half-life than the native compound, and indicated in the treatment of severe chronic limb ischemia.1,21–23 Results from pilot studies and case reports also described the positive effects of iloprost in the management of acute ischemia secondary to various causes, particularly after accidental intra-arterial administration of drugs or toxic agents.24–26 Several preclinical studies have assessed the effects of iloprost in experimental ischemia-reperfusion injury and documented the actions of the compound on different pathophysiologic mechanisms potentially relevant for damage following ALI.27–32 A diagram indicating where iloprost can interfere in the mechanisms, leading from ischemia and reperfusion, to the development of no-reflow and reflow-paradox, is reported in Figure 1. 33 FIGURE 1. Pathobiological mechanisms leading from ischemia-reperfusion, to “no-reflow”/“reflow-paradox.” Points where iloprost can act are indicated (from de Donato et al33). Some years ago, we performed a placebo-controlled, double-blind pilot study in 30 patients with ALI undergoing Fogarty's thromboembolectomy. Encouraging results were obtained with the use of intraoperative and postoperative iloprost (lower incidence of major clinical events, more evident metabolic improvement by means of transcutaneous tensiometry).34 In this paper, we report the results of ILoprost in Acute Ischemia of Lower Limbs (ILAILL) study, a larger, multicenter trial including patients undergoing all types of surgical revascularization, who received iloprost or placebo administration during intervention and therefore for 4 to 7 days, and were observed for a 3-month postoperative period.

Objectives To evaluate the effects of iloprost, in addition to surgery, on the outcome of acute lower limb ischemia (ALLI). Design Post-hoc analysis of a randomized, double-blind, placebo-controlled study. Methods In the context of the ILAILL (ILoprost in Acute Ischemia of Lower Limbs) study, 192 elderly patients (>70 years old) undergoing surgery for ALLI were assigned to receive perioperative iloprost (intra-arterial, intra-operative bolus of 3000ng, plus intravenous infusion of 0.5–2.0ng/kg/min for six hours/day for 4–7 days following surgery), or placebo (iloprost: n =100; placebo: n =92). Patients were followed-up for three-months following surgical revascularization. Results The combined incidence of death and amputation (primary study end-point) was significantly reduced in patients treated with iloprost (16.0% vs 27.2% in the placebo group; hazard ratio 1.99, 95% confidence interval 1.05–3.75, p =0.03). A statistically significant lower mortality (6.0%) was reported in patients receiving iloprost, compared to controls (15.2%) (hazard ratio 2.93, 1.11–7.71, p =0.03). The overall incidence of death and major cardiovascular events was lower in patients receiving iloprost compared to those assigned placebo (24.0% and 35.9%, respectively), at the limits of statistical significance (relative risk 1.64, 0.97–2.79, p =0.06). Conclusions These results confirm the poor outcome in elderly patients with ALLI. Based on a subgroup analysis iloprost, as an adjuvant to surgery, appears to reduce the combined end-point of death and amputation.

To determine whether patients undergoing carotid endarterectomy (CE) for symptomatic left internal carotid artery (LICA) stenosis have greater risk of cognitive decline than patients with asymptomatic LICA disease or right internal carotid artery (RICA) disease.Observational.Vascular surgery day hospital.The analysis included 103 patients (mean age 72.6+/-7.0, 73 men), of whom 50 had LICA disease (29 symptomatic).Cognitive function was evaluated (age- and education-adjusted Mini-Mental State Examination (MMSE), and Clock tests (CLOX1 and 2)) at baseline and at the end of the study period (average follow-up+/-standard deviation 44.4+/-14.3 months) in a sample of patients aged 65 and older, free from cognitive impairment, consecutively undergoing CE.At the end of the study period, MMSE, CLOX1, and CLOX2 scores were significantly lower in patients with symptomatic LICA disease (P.001, P.001, and P=.002, respectively) and not in the other groups of patients. Patients with symptomatic LICA disease had greater risk of cognitive decline than other individuals according to MMSE score (F=5.18, P=.002) or CLOX1 and 2 scores (F=5.66, P=.001, and F=4.33, P=.006, respectively).Patients undergoing CE for symptomatic LICA disease appear to be at greater risk of cognitive decline than other subjects. These findings suggest that future studies should evaluate the effects on cognitive function of different timing for CE in patients with LICA and RICA disease.

The infection of a prosthetic vascular graft (PVGI), although rare, is the most severe complication in reconstructive vascular surgery. The early diagnosis of this complication reduces the death rate from surgery. Aortofemoral graft infections differ clinically from peripheral graft infections in significant ways. The aim of this article is to evaluate separately the reliability of the 99mTc-HMPAO-labeled leukocyte scan or white blood cell count (WBC) in the early detection of both aortofemoral and peripheral graft infections.One hundred sixty-two WBCs were performed on 129 consecutive patients with suspected aortofemoral (122 scans) and peripheral (40 scans) graft infection and in a 12-patient control group. Patients with suspected PVGI were categorized into three groups on the basis of their signs and symptoms on readmission: (a) patients with specific signs of graft infection (Group A); (b) patients with nonspecific signs of graft infection (Group B); and (c) patients with anastomotic aneurysms (Group C). Gram's stains of the perigraft exudate and graft cultures were performed and used as the gold standard in patients who underwent surgery. An 18-mo clinical follow-up was done to assess the presence or absence of graft infection in patients who did not have surgery.In patients with suspected aortofemoral graft infections, the overall sensitivity, specificity and accuracy of WBCs (Groups A, B, C) were 100%, 92.5% and 97.5%, respectively, whereas sensitivity, specificity and accuracy calculated in the patients with nonspecific signs of graft infection (Groups B, C) were 100%, 92.3% and 96.9%, respectively. In patients with suspected peripheral graft infections, sensitivity, specificity and accuracy were 100%.The white blood cell scan seems a reliable diagnostic method for early diagnosis of PVGI, and it is more useful in aortofemoral graft infections.

A rare case of a giant extradural neurinoma of the IV lumbar root with an anterior development and a soft neurological picture is reported. The Authors stress the important role of CT both in the neurinoma diagnosis and in the correct preoperative evaluation of its extension and its relationship with contiguous organs.

Efficient surface functionalization with polydopamine (PDA) films can be easily achieved on virtually any object via single immersion in slightly basic dopamine solutions. In such conditions, however, poor homogeneity, low thickness, and long time of reaction are usually the major limitations. Herein, we report a rational entry to the control of PDA deposition via chemical oxidation under slightly acidic conditions (pH 5.0) ensuring inhibition of uncontrolled autoxidation processes to gain insight about the reaction mechanism and the impact of oxidation conditions on PDA structure. Comparative chemical analysis of dopamine oxidation with three different oxidants (ammonium peroxodisulfate, sodium periodate, and copper sulfate) revealed significant differences in the reaction course and allowed selection of periodate for the fast and homogeneous deposition of PDA films with thickness never before reported. Notably, PDA coatings with unprecedented superhydrophilic/superoleophobic properties were obtained under conditions of high periodate concentration due to degradation of quinone units to yield carboxyl functions. Moreover, these films still present biocompatibility and metal cation reduction properties. Overall, these results provide a novel rational methodology to tailor PDA coatings for technological applications based on periodate control over dopamine polymerization and postsynthetic functional group modification.

To characterize the performance of Membrane Distillation (MD) modules, channels filled with woven spacers were investigated by Computational Fluid Dynamics (including Direct Numerical Simulations and the use of the SST k-ω turbulence model) and by parallel experiments with Thermochromic Liquid Crystals. The cases considered here regard mutually orthogonal filaments with a spacer pitch to channel height ratio P/H=2, two spacer orientations θ with respect to the main flow (0° and 45°), and bulk Reynolds numbers Re from ∼200 to ∼2000, an interval of great interest in practical MD applications. For both values of θ, CFD predicted steady-state flow for Re up to ∼300, and chaotic flow for Re larger than ∼400. In the intermediate range Re≈300-400, periodic flow regimes were predicted for both orientations. These regimes were of particular interest and complexity, as they exhibited a slow global oscillation of the flow superimposed on high order harmonics corresponding to fast local oscillations. Experiments confirmed the appearance of unsteadiness for Re>∼300. Heat transfer and friction were little affected by unsteadiness and exhibited a smooth behaviour with Re. The agreement with the experimental results was good using DNS, and acceptable using RANS.