Lower Limb Revascularization Research Articles

Effect of Triclosan‐Coated Sutures on the Incidence of Surgical Wound Infection After Lower Limb Revascularization Surgery: A Randomized Controlled Trial

Surgical wound infection (SWI) is a common complication after peripheral vascular surgery. In a prospective study, triclosan-coated sutures were reported to decrease the incidence of surgical site infection after various surgical procedures. The aim of our study was to test the hypothesis that use of triclosan-coated sutures decreases the incidence of SWI after lower limb vascular surgery. This prospective, randomized, multicenter, double-blinded trial was conducted between July 2010 and January 2011 in five hospitals in Finland. We randomly allocated 276 patients undergoing lower limb revascularization surgery to a study (n = 139) or a control (n = 137) group. Surgical wounds in the study group were closed with triclosan-coated suture material, and wounds in the control group were closed with noncoated sutures. The main outcome measure was SWI. A surgical wound complication was considered to be an infection if there were bacteria isolated from the wound or if there were areas of localized redness, heat, swelling, and pain around the wound appearing within 30 days after the operative procedure. Logistic regression analysis was used to assess the independent effect of triclosan-coated sutures on the incidence of SWI. Altogether, 61 (22.1 %) patients developed SWI. SWI occurred in 31 (22.3 %) patients in the study group and in 30 (21.9 %) patients in the control group (odds ratio 1.10, 95% confidence interval 0.61-2.01, p = 0.75.) The use of triclosan-coated sutures does not reduce the incidence of SWI after lower limb vascular surgery.

Neutrophil-Lymphocyte Ratio Predicts Graft Patency Following Lower Limb Revascularisation

Background : Graft failure is a significant problem following lower limb revascularisation. We hypothesised that the neutrophil-lymphocyte ratio (NLR), a simple and inexpensive index of systemic inflammation, predicts graft failure.Methods : Consecutive patients undergoing infra-inguinal bypass grafting were identified from a prospective database. All patients underwent routine graft surveillance using Duplex ultrasound. Potential predictors of graft failure (occlusion or ipsilateral amputation) were assessed in univariate and multivariate regression models.Results : Of 126 patients, 79 had patent grafts at 1 year. The only independent predictor of graft failure was the postoperative NLR.Conclusion : Post-operative NLR may be a simple, inexpensive means of focussing surveillance resources on patients at high-risk of graft failure. Its value needs to be confirmed in larger cohorts.

Post-implant evaluation of the anastomotic mechanical and geometrical coupling between human native arteries and arterial cryografts implanted in lower-limb: Mechanical, histological and ultraestructural studies of implanted cryografts

Background There is an urgent need of vascular substitutes (VS) to be used in lower limb revascularization procedures when autologous veins are not available and synthetic prosthesis are contraindicated. Since the mechanical differences with respect to native vessels are determinants of the VS failure, the substitutes should have mechanical properties similar to those of the recipient vessels. The use of cryopreserved arteries (cryografts) could overcome limitations of available VS. These work aims were to characterize (a) native vessels/implanted cryografts mechanical and geometrical coupling, (b) cryografts capability to ensure mismatch levels lesser than those expected for expanded polytetrafluoroethylene (ePTFE), (c) cryografts functional properties considering their histological and ultra-structural characteristics. Methods Instantaneous pressure (mechano-transducers) and diameter (B-mode echography) were obtained in implanted femoro-popliteal, ileo-femoro-popliteal and axilo-humeral cryografts ( n = 8), in femoral arteries from recipients ( n = 8), recipient-like ( n = 15) and multiorgan donors-like ( n = 15) subjects, and in ePTFE segments ( n = 10). Calculus: (a) Mechanical parameters: elastic modulus, arterial compliance, distensibility and characteristic impedance; (b) Arterial remodeling: diameter, wall thickness, cross-sectional area and wall-to-lumen ratio; (c) Native vessels/VS coupling. Histological and structural analysis were done in explanted femoro-popliteal and axilo-humeral cryografts ( n = 7). Results Post-implant the cryografts remodeled. Their stiffness increased and the conduit function diminished. Remodeling resulted in an improvement in native vessels/cryograft coupling, which was always better than native vessels/ePTFE coupling. Conclusions Post-implant cryograft remodeling improved native vessels/cryografts coupling. Cryografts would have mechanical and geometrical advantages over ePTFE. Anastomotic cryograft remodeling differed from that expected only due to haemodynamic factors. The structural properties of the remodeled cryografts contribute to explain their functional characteristics.

Microbial Pathogenesis of Bacterial Biofilms

Vascular surgical site infection (SSI) is caused by pathogenic bacterial strains whose preferred mode of growth is within a surface biofilm. Bacterial biofilm formation can develop within hours to days in a wound and produces a recalcitrant infectious process especially in the presence of a prosthetic graft. The initial steps of biofilm formation are bacterial adhesion to biologic or inert surgical site structures followed by organism production of exopolysaccaride matrix which encases developing bacteria colonies to produce a protective microenvironment. As the biofilm matures, a dynamic process of organism cell-to-cell signaling occurs with varying growth modes of sessile bacteria within the biofilm and the release of planktonic bacteria with the potential to spread and expand the biofilm-mediated infection. The prevalence of staphyloccocal strains causing vascular SSI is best understood when viewed as a biofilm-mediated infection with virulence factors related to specific cell surface adhesion proteins and bacteria-derived matrix production. Nonhealing surgical sites following lower limb revascularization, the late appearance of prosthetic graft infection caused by Staphylococcus epidermidis, and the development of groin site tracts after aortofemoral bypass grafting are clinical examples of a biofilm-mediated SSI. A mature biofilm within a wound or coating a prosthetic device exhibits resistance to host defenses and selected antibiotics, impairs wound healing, and is a perpetual irritant to that host by inciting a chronic inflammatory process. By understanding the microbial pathogenesis of biofilm formation, strategies to treat and prevent biofilm-mediated infection can be developed and utilized to reduce vascular SSIs.

Crioplastia para tratamento da doença arterial fêmoro-poplítea

CONTEXTO: O tratamento endovascular da doença arterial obstrutiva periférica apresenta baixa morbidade e mortalidade, no entanto, a perviedade dos stents a médio e longo prazo ainda é controversa. A crioplastia foi desenvolvida para reduzir os grandes desafios da angioplastia: dissecção, retração e reestenose. OBJETIVO: Avaliar os resultados clínicos e a perviedade a médio prazo em pacientes submetidos à técnica de crioplastia da doença arterial do território femoro-poplíteo. MÉTODOS: Pacientes com indicação de revascularização de membro inferior por técnica endovascular do território femoro-poplíteo, segundo as classificações clínicas de Fontaine e Rutherford e classificações anatômicas do TASC II, foram submetidos à crioplastia com cateter balão PolarCath®. No seguimento, foram avaliadas as manifestações clínicas e perviedade anatômica pelo duplex scan. RESULTADOS: Dez pacientes foram submetidos à angioplastia do território femoro-poplíteo utilizando a técnica de crioplastia. Nove pacientes apresentavam quadro clínico de claudicação limitante do membro inferior e um paciente apresentava úlcera isquêmica, três pacientes apresentavam lesão classe B pelo TASC II e sete pacientes, classe A. Sucesso técnico angiográfico inicial foi obtido em todos os casos, sendo que um caso necessitou do implante de stent devido à dissecção. Seguimento foi realizado em 9 pacientes, por período médio de 31,6 meses (28-35), com perviedade primária de 77,7% e perviedade secundária de 100%. Todos os pacientes apresentam-se assintomáticos no final do seguimento (Fontaine I). CONCLUSÕES: A crioplastia do território femoro-poplíteo é um método seguro, de baixa morbidade, com resultados a curto e médio prazo comparáveis à angioplastia convencional e com potencial de reduzir as taxas de dissecção e retração durante o procedimento, e redução do grau de reestenose a médio e longo prazo.

Fatal Cardiac Perforation after Percutaneous Treatment in Iliac Artery Occlusion

IntroductionA 68-year-old male smoker was admitted to the hospitalwith a history of bilateral severe lower limb arterial dis-ease. He had claudication due to infrainguinal disease,mainly related to a left common iliac artery occlusion, asrevealed by arteriography (Fig. 1A–C). The patient wastreated with percutaneous transluminal angioplasty (PTA)(Fig. 1D) and stenting (Fig. 1E) through the left brachialartery using a metallic guide wire and a 6F long hydro-philic polytetrafluoroethylene-coated sheath.During the intervention, the radiologist used fluoroscopyto aid placement, but only for visualizing the occluded iliacartery without following the entire route taken by the guidewire. Therefore, he did not notice the erroneous pathwaytaken by the guide wire through the ascending aorta andreaching the cardiac chambers. In a second attempt, afterpulling the guide wire back, the radiologist correctlyredirected it, entering into the descending aorta andreaching the left common iliac artery, where the stent wassuccessfully placed, resulting in revascularization of theleft lower limb (Fig. 1F).Two hours after the intervention, the patient was foundlifeless in his hospital bed; all resuscitation efforts wereunsuccessful.ResultsGross Autopsy FindingsA complete postmortem examination was performed3 days after death. External examination was unremarkableexcept for the puncture site of the PTA in the left arm.The internal examination revealed cardiac tamponade(Fig. 2A); however, a definitive transmural myocardialdefect was not identified. There was evidence of hemor-rhagic infiltration beginning in the epicardium andcontinuing throughout the myocardium at the distal part ofthe left ventricle (Fig. 2B).At the aortic root, a small area of hemorrhagic infiltra-tion in contact with the fibrous pericardium was found.A correctly positioned stent was found in the left com-mon iliac artery. Other significant findings included mul-tiorgan vascular congestion and cerebral and pulmonaryedema.Histological StudiesHistological studies were performed with formalin-fixed,paraffin-embedded tissue sectioned at 4 lm and stainedwith hematoxylin and eosin. The examination of the heart,performed by making seven consecutive myocardial sec-tions, revealed hemorrhagic dissection of myocardial tissueat the level of the left ventricle, consistent with cardiacrupture. The transmural myocardial defect was found; thedefect was compatible with a lesion that could have been

Trends and outcomes after surgical lower limb revascularization in England

The aim was to analyse contemporary data on the number of surgical revascularization procedures performed each year in England, and their outcome. Hospital Episode Statistics and Office for National Statistics data were used to quantify numbers and identify factors associated with outcome after all femoropopliteal and femorodistal bypass procedures performed between 2002 and 2006. Outcome measures were repeat bypass, major amputation, death and a composite measure. Single-level multivariable logistic regression modelling was used to quantify the effect of these variables on outcome. A total of 21,675 femoropopliteal and 3458 femorodistal bypass procedures were performed. Mean in-hospital mortality rates were 6·7 and 8·0 per cent respectively. One-year survival rates were 82·8 and 79·1 per cent; both increased over the study interval. The mean 1-year major amputation rate after femoropopliteal bypass was 10·4 per cent, which decreased significantly over the 5 years (P < 0·001); after distal bypass the rate of 20·8 per cent remained unchanged (P = 0·456). Diabetes mellitus and chronic kidney disease were significant predictors of adverse outcome for both procedures: odds ratio (OR) at 1 year 1·56 (95 per cent confidence interval 1·46 to 1·67; P < 0·001) and 2·15 (1·88 to 2·45; P < 0·001) respectively for femoropopliteal bypass. Previous femoral angioplasty was associated with an increased rate of major amputation 1 year after proximal bypass (OR 1·18, 1·05 to 1·33; P = 0·004). Although all mortality rates are improving, the major amputation rate remains high after femorodistal bypass. Adverse events occurred after 37·6 per cent of femoropopliteal and 49·7 per cent of femorodistal bypasses; diabetes and chronic renal failure were the main predictors of poor outcome.

Impact of renal insufficiency on clinical outcomes in patients with critical limb ischemia undergoing endovascular revascularization

Patients with renal insufficiency (RI) are frequently excluded from trials assessing various endovascular revascularization concepts in critical limb ischemia (CLI) although information on clinical outcomes is scarce. Consecutive patients with CLI undergoing endovascular lower limb revascularization during a 4.5-year time interval at a tertiary referral center were prospectively followed over a 12-month period. Patients were grouped according to renal function defined as normal (estimated glomerular filtration rate [eGFR] ≥ 60 mL/min/1.73 m(2); n = 108, 49.5%), moderate RI (eGFR ≥ 30-59 mL/min/1.73 m(2); n = 86, 39.5%) and severe RI, including dialysis (eGFR < 30 mL/min/1.73 m(2); n = 24, 11%). Clinical endpoints assessed were sustained clinical success, peri- and postprocedural mortality and major, above-the-ankle amputation. Sustained clinical improvement was defined as an upward shift of at least one category on the Rutherford classification compared with baseline to a level of claudication without repeated revascularization or unplanned amputation in surviving patients. Survival analysis was performed using the Kaplan-Meier method. Multivariate regression analysis was conducted in separate models for all above-mentioned clinical endpoints. A total of 208 patients (218 limbs, mean age 77.1 ± 9.5, 131 men) underwent endovascular revascularization. Technical success rate was 95.2%, 92.5%, and 100% in patients without, moderate or severe RI. Sustained clinical success was 81.7%, 74.1%, and 51.5% in patients with normal renal function, 87.8%, 67.0%, and 63.3% with moderate, and 81.0%, 64.6%, and 50.2% with severe RI (P = .87 by log-rank) at 2, 6, and 12 months. Accordingly, major amputation rates were 9.9%, 18.2%, and 20.8% vs 9.9%, 22.6%, and 24% vs 12.5%, 16.7%, and 21.1% (P = .83, by log-rank). Mortality rates were 8.4%, 17.6%, and 26.5% in patients with normal renal function, 9.6%, 17.6%, and 30.1% with moderate and 17.5%, 26.6%, and 31.9% in patients with severe RI (P = .77, by log-rank) at corresponding intervals. Multivariate analysis revealed eGFR (hazard ratio [HR], 1.016; 95% confidence interval [CI], 1.001-1.031; P = .036), age (HR, 1.12; 95% CI, 1.061-1.189; P < .0001) and cigarette smoking (HR, 3.14; 95% CI, 1.153-8.55; P = .026) to be predictors for increased mortality within 1 year of follow-up. While functional lower limb outcomes were not influenced by renal function in this study, presence of RI was an independent predictor for higher mortality in CLI patients undergoing endovascular revascularization.

Supplemental Postoperative Oxygen in the Prevention of Surgical Wound Infection after Lower Limb Vascular Surgery: A Randomized Controlled Trial

Surgical wound infection (SWI) is a common complication after peripheral vascular surgery. Infections increase morbidity and costs of treatment. The aim of the present study was to test the hypothesis that supplemental postoperative oxygen decreases the incidence of SWI after lower limb revascularization. This prospective, randomized, multicenter, single-blinded trial was conducted between May 2009 and February 2010 in six secondary referral hospitals in Finland. We randomly allocated 274 patients undergoing surgery for lower limb revascularization to the study group (n=137) or a control group (n=137). The study group received supplemental inspired oxygen for the first 2 days after surgery. The main outcome was SWI. Patients were followed up for 30 days or until the SWI was healed. Logistic regression analysis was used to assess the independent effect of supplemental oxygen on the incidence of SWI. Altogether 63 (23%) patients developed SWI; 47 (75%) of the infections were superficial. There were two vascular graft infections. SWI occurred in 25 patients (18.2%) in the study group and in 38 patients (27.7%) in the control group [odds ratio (OR) 0.56, 95% confidence interval (CI) 0.30-1.04; P=0.07]. In isolated groin incisions, 3 patients of 52 (5.8%) in the study group and 12 patients of 51 (23.5%) in the control group developed SWI; OR=0.20, 95% CI 0.04-0.95; P=0.04. There was an indication that supplemental inspired oxygen tended to decrease the incidence of SWI after lower limb vascular surgery. In isolated groin incisions, the decrease of SWI incidence in the supplemental oxygen group was significant.

Neutrophil-Lymphocyte Ratio Predicts Medium-Term Survival Following Elective Major Vascular Surgery: A Cross-Sectional Study

The systemic nature of atherosclerosis compromises medium-term survival following major vascular surgery. Neutrophil-lymphocyte ratio (NLR) is a simple index of systemic inflammatory burden which correlates with survival following percutaneous coronary intervention. Patients undergoing elective major vascular surgery in 2 tertiary vascular units were identified from prospectively maintained databases. Factors associated with 2-year mortality were assessed by univariate and multivariate analyses. Over a 4-year period, 1021 patients underwent elective major vascular surgery (carotid endarterectomy, abdominal aortic aneurysm repair, lower limb revascularization). Two-year mortality was 11.2%. In multivariate analysis, preoperative NLR > 5 was independently associated with 2-year mortality (multivariate odds ratio [OR] 2.21; 95% confidence interval [CI] 1.22-4.01). Preoperative NLR identifies patients at increased risk of death within 2 years of major vascular surgery. This simple index may facilitate targeted preventive measures for high-risk patients.

Factors influencing early results of femoro-femoral crossover bypass

Femoro-femoral crossover bypass is an extraanatomic reconstruction used for revascularization of lower limb with contralatateral femoral artery as an inflow vessel, and the graft placed in the suprapubic region. We perform this procedure when anatomic reconstruction is not possible or is contraindicated. To analyze the influence of different risk factors on early patency of femoro-femoral crossover bypass. This retrospective study analyzed the results of 88 femoro-femoral bypass grafting during an 11-year period. There were 66 (75%) males and 22 (25%) females of average age 64.93 years (42-79 years). In 76 patients the operations were performed due to critical limb ischemia. Revascularization was urgent in 12 patients, while 76 patients were elective. Dacron prosthesis was used in 81 patients, while PTFE was used in 7 patients. Statistical analysis was made by logistic regression. During hospitalisation the graft remained patent in 82 patients, and graft thrombosis occurred in 6 patients. Limb salvage rate was 90.91%. Early morbidity rate (within the first postoperative month) was 13.64%, while early mortality rate was 4.55%. Using logistic regression we established that early graft patency was statistically more significant in males (p < 0.05). Age (p = 0.07) and hypertension (p = 0.08) appeared to be predicting influence of the graft patency on the border of the accepted statistical significance level. Femoro-femoral crossover bypass is a good alternative for revascularization in high risk patients for standard anatomic reconstructions due to comorbid conditions or local problems.

Vascular Hospitalization Rates and Costs in Patients With Peripheral Artery Disease in the United States

Peripheral artery disease (PAD) is common and imposes a high risk of major systemic and limb ischemic events. The REduction of Atherothrombosis for Continued Health (REACH) Registry is an international prospective registry of patients at risk of atherothrombosis caused by established arterial disease or the presence of ≥3 atherothrombotic risk factors. We compared the 2-year rates of vascular-related hospitalizations and associated costs in US patients with established PAD across patient subgroups. Symptomatic PAD at enrollment was identified on the basis of current intermittent claudication with an ankle-brachial index (ABI) <0.90 or a history of lower-limb revascularization or amputation. Asymptomatic PAD was diagnosed on the basis of an enrollment ABI <0.90 in the absence of symptoms. Overall, 25 763 of the total 68 236-patient REACH cohort were enrolled from US sites; 2396 (9.3%) had symptomatic and 213 (0.8%) had asymptomatic PAD at baseline. One- and cumulative 2-year follow-up data were available for 2137 (82%) and 1677 (64%) of US REACH patients with either symptomatic or asymptomatic PAD, respectively. At 2 years, mean cumulative hospitalization costs, per patient, were $7445, $7000, $10 430, and $11 693 for patients with asymptomatic PAD, a history of claudication, lower-limb amputation, and revascularization, respectively (P=0.007). A history of peripheral intervention (lower-limb revascularization or amputation) was associated with higher rates of subsequent procedures at both 1 and 2 years. The economic burden of PAD is high. Recurring hospitalizations and repeat revascularization procedures suggest that neither patients, physicians, nor healthcare systems should assume that a first admission for a lower-extremity PAD procedure serves as a permanent resolution of this costly and debilitating condition.

Limb Salvage With CryoVein Cadaver Saphenous Vein Allografts Used for Peripheral Arterial Bypass: Role of Blood Compatibility

Patients suffering from limb-threatening ischemia often have scarce or inadequate autogenous veins for complex lower limb revascularization. One option for such patients is to use conduit consisting of cadaver saphenous vein allograft (CSVA) as a final surgical option before limb amputation. This study reviewed retrospectively the patency of CryoVein CSVA allografts, processed by CryoLife, Inc., in 54 implant cases of lower extremity arterial bypass over a span of 6 years. Patient demographics, graft patency, limb salvage, and blood type matching of donor to recipient were analyzed. Kaplan-Meier analysis showed postoperative primary patency rates of 89, 63%, 30%, 17%, and 9% at 1, 3, 6, 12, and 18 months, respectively. Secondary patency rates were 89%, 74%, 63%, 63%, and 54% at 1, 3, 6, 12, and 18 months, respectively. Limb salvage rates were 67% at 12 months and 54% at 18 months. Median follow-up was 467 days. Of the 34 cases where the patient received a blood-group compatible CSVA, 30 had limb salvage and only six of 20 noncompatible grafts offered limb salvage (p = 0.05). Although primary patency rate was poor at 1 year, high secondary patency and limb salvage rates support the use of CSVA as a peripheral bypass conduit alternative. Cases with donor-recipient ABO blood type compatibility had significantly better limb salvage.

Significant Prostacyclin/Thromboxane Level Imbalance after Lower Limb Arterial Angioplasty: A Possible Platelet Function Alteration

The authors investigated prostacyclin (PGI2) and thromboxane (TX) productions in peripheral venous blood after lower limb revascularization by percutaneous transluminal angioplasty (PTA) versus diagnostic angiography. The purpose of this study was to investigate PGI2/TX imbalance after PTA. This imbalance is of pathophysiologic importance and it is a potential sign of platelet function alteration. Twenty-five patients requiring PTA were compared with 20 patients undergoing angiography alone from April 2004-December 2005 from a single vascular unit. Patient age range was 42-90 years, and the majority of patients were men. Prostaglandin F2-alpha (PGF2-alpha) and thromboxane B2 (TXB2) were measured sequentially (preprocedure, at 1 hour, and 24 hours after procedure). Differences between postprocedure and preprocedure level were compared statistically between angiography and PTA. Baseline demographics were distributed equally between the two groups except presence of critical ischemia and ankle brachial pressure index, which were two significant confounders. TXB2 was significantly higher after PTA at 1 hour and 24 hours after PTA (P = .005 and P = .014 respectively), PGF2-alpha was significantly higher 24 hours after PTA only (P = .018) (Mann-Whitney U test). PGI2/TX balance homeostasis is of significant pathophysiologic importance. The authors found that PTA results in significant PGI2/TX imbalance and shifts more toward increased TX production. This finding is partly suggestive of significant platelet activation. This imbalance in PGI2/TX level may have implications for future failure of PTA. Future research in reducing this platelet activation is recommended.

Tratamiento de las oclusiones crónicas en el sector femoropoplíteo mediante técnicas endovasculares

Introduction Advances in endovascular techniques have provided new options in the treatment of complex infrainguinal occlusive lesions. Aims To evaluate the effectiveness and patency of endovascular treatment in patients with femoropopliteal occlusive disease. Methods All patients undergoing endovascular interventions for superficial femoral artery and above knee popliteal artery obstructions between February 1997 and February 2009 were retrospectively reviewed and assessed for comorbidities, operative and follow-up variables potentially associated with restenoses and limb salvage. Results During the study period, 52 patients were treated. Patients were 71.7 years (range 40 to 94), 69.2% male, 53.8% diabetic, 69.2% current or former smokers, and 67.3% hypertensive. Lesions were 28.8% TASC II C, 46.2% TASC II B, and 25% TASC II A. Mean recanalization length was 73.6 mm (range 20 to 150 mm). There were three embolizations, and four early thrombosis. Mean follow-up time was 18 months (range 1 to 115), based on clinical, hemodynamic, and ultrasound data. Primary patency rates were 85%, 76.8%, 60% and 52.5% at 3, 6, 12 and 24 months. Ten restenoses were successfully treated. The assisted primary patency rates were 85%, 82.3%, 74% and 74% at 3, 6, 12 and 24 months. Eight complete occlusions could not be reverted by a second recanalization procedure, and were treated by surgical bypass (6 cases) and amputation (2 cases). The secondary patency rates were 91.4%, 86%, 76.4% and 76.4% at 3, 6, 12, and 24 months. Conclusions Endovascular recanalization is a viable and effective strategy for lower limb revascularization in selected patients.

Extra-anatomical bypass grafting – a single surgeon's experience

Extra-anatomical bypass grafting is a recognised method of lower limb re-vascularisation in high-risk patients who cannot tolerate aortic cross clamping, or in those with a hostile abdomen. We present a single surgeon series of such procedures and determine relevant outcomes. A retrospective review was performed on a prospectively maintained database of patients undergoing femoro-femoral or axillo-femoral bypass surgery between 1986 and 2004. Patency rates for femoral (n = 28; 32%) versus axillary (n = 59; 68%) bypass procedures at 1 month, 1, 3 and 5 years were (92% vs 93%), (69% vs 85%), (60% vs 72%) and (55% vs 67%), respectively. Patient survival rates for the corresponding procedures and time intervals were (96% vs 90%), (96% vs 67%), (85% vs 45%) and (73% vs 38%) and revealed a significantly lower survival rate in those undergoing axillary procedures (P = 0.002). Limb salvage rates were calculated at (100% vs 91%), (96% vs 84%), (96% vs 81%) and (92% vs 81%) with no statistically significant difference found between the two groups (P = 0.124). Two-thirds of the patients who required major amputation died within 12 months of surgery. Acceptable 30-day morbidity, long-term primary patency and survival rates are obtainable in patients suitable for extra-anatomical bypass surgery despite having significant co-morbidities. We have shown 5-year patency rates in those that survive axillary procedures to be as good as those undergoing femoral procedures. Furthermore, surviving patients who evade amputation within a year have an excellent chance of long-term limb salvage.

Anaesthetic Specialisation Leads to Improved Early- and Medium-term Survival Following Major Vascular Surgery

Objective Vascular surgical specialisation is associated with improved outcomes. We aimed to assess the effect of anaesthetic specialisation on outcome following major vascular surgery. Design Retrospective cohort study. Methods Patients undergoing major vascular surgery (lower limb revascularisation, elective and ruptured abdominal aortic aneurysm repair, endovascular aneurysm repair and carotid endarterectomy) over a five-year period were identified from a prospective database. The primary outcomes were death within 30 days and death within two years of surgery. Potential risk factors for mortality were assessed using multivariate logistic regression modelling. Results The analysis cohort comprised 1155 patients followed up for a median of 583 days. Mortality within two years of surgery was 16%. For the overall cohort, care from vascular anaesthetists was independently associated with reduced 30-day (odds ratio 0.22; 95% CI 0.12–0.62) and medium-term mortality (0.31; 95% CI 0.18–0.55). For elective patients ( n = 851), vascular anaesthesia reduced two-year mortality (odds ratio 0.29; 95% CI 0.15–0.58; P = 0.0004) though not 30-day mortality (odds ratio 0.55; 95% CI 0.15–1.95; P = 0.35). For emergency patients, care by a vascular anaesthetist influenced neither 30-day mortality (odds ratio 0.33; 95% CI 0.08–1.41; P = 0.13) nor medium-term mortality (odds ratio 0.45; 95% CI 0.17–1.21; P = 0.11). Conclusions Anaesthetic specialisation reduced early- and medium-term mortality rates following major vascular surgery. If replicated by prospective studies, these results suggest that vascular surgery services would benefit from specialised anaesthetic support.

An Effective Guidewire Looping Technique for the Recanalization of Occlusive Segments of Infrapopliteal Vessels

ObjectiveTo determine the efficacy, safety and primary follow-up results of a guidewire looping technique for the treatment of infrapopliteal arteries.Materials and MethodsFrom October 2006 to May 2008, an intraluminal angioplasty of the infrapopliteal arteries was attempted in 200 consecutive patients. Altogether, 417 infrapopliteal lesions, with lengths varying from 2 cm to 32 cm, were treated as part of this study, including 305 lesions in the anterior tibial arteries, 89 in the posterior tibial arteries, and 23 in the peroneal arteries. The 'U'-shaped guidewire technique was attempted in 393 lesions from 361 limbs. The tip of a hydrophilic 0.035-inch guidewire was formed into a 'U' shape with the aid of a 4-Fr catheter and collateral branch vessel to recanalize the completely occluded long segment lesions.ResultsA successful angioplasty with at least one artery recanalized directly to the malleolar or dorsal foot was achieved in 322 limbs (89%). The looping technique had a success rate of 90% (352 of 393 lesions). After the procedure, the rest pain was relieved in 58 of 69 patients, while 207 of 245 limbs (85%) showed improvement for intermittent claudication. Complete wound healing was noted in 21 of 54 patients, while 20 of 54 patients showed an improvement in the wound size or depth. A total of 38 major immediate procedure-related complications were noted, including retroperitoneal hematoma, distal emboli, and vessel rupture.ConclusionThe results of this study suggests that the guidewire looping technique is a safe and effective method for the recanalization of the occluded lesions in infrapopliteal vessels.

Proteomic profiling of oxidative stress in human victims of traffic-related injuries after lower limb revascularization and indication for secondary amputation

Microsurgical replantation and revascularization are frequently performed to salvage devascularized severe lower-extremity fractures in the human victims of road traffic-related injuries. However, some patients require secondary amputation within 1 week of successful revascularization due to tissue necrosis and sepsis. Enhanced efforts to understand the underlying molecular mechanism of such events are needed and should characterized in depth. Thus, functional proteomics were applied in this study to evaluate the role of oxidative stress in acute injury following microsurgery in a set of human subjects surviving serious road traffic accidents. Changes in the levels of protein volume and the accompanying content in protein carbonylation were visualized using two-dimensional electrophoresis (2-DE) and immunoblot analysis. Since oxidation of some acute-phase proteins not only causes them to lose their function as antioxidants but also initiates the intracellular stress signaling pathway that regulates cytokine and chemokine responses, how cytokine expression correlated with oxidative stress was also evaluated via protein array assays. It was observed that the growth-regulated oncogene protein family (GRO), the range of IL-6, IL-8, IL-10 and monocyte chemotactic protein-1 (MCP-1), which are responsible for neutrophil and monocyte aggregation with subsequent cytotoxic effects, were significantly elevated in the plasma of amputees subjects, whilst the level of chemokine recruiting leucocytes into inflammatory sites (RANTES) was diminished in the salvaged group of patients. Our results suggest that severely oxidative injury during revascularization perturbs the normal redox balance and induces carbonylation of specific proteins, thereby activating pro-inflammatory factors leading to severe tissue damage. The dissimilar 2-DE protein and cytokine profiles revealed here might reflect distinct etiologies resulting in oxidative damage to tissues and may serve as pivotal indicators of local necrosis and the subsequent need for secondary amputation of limbs. We believe that the combination of proteomic and cytokine profile results presented in this work offers more reliable information and defines more sophisticated criteria in clinical practice than currently used C-reactive protein levels (CRP) or white blood cells counts (WBC) for predicting secondary amputation requirements in patients requiring limb salvage surgery.

Análise espectral segmentar no seguimento de pacientes revascularizados

CONTEXTO: Pacientes tratados por revascularização arterial (enxertos e angioplastias) nos membros inferiores acometidos por doença arterial oclusiva periférica foram seguidos por até 2 anos pós-tratamento usando ultrassom vascular (análise espectral segmentar, AES). OBJETIVO: Demonstrar que a AES pode ser utilizada no seguimento dos pacientes tratados por doença arterial oclusiva periférica. MÉTODOS: As medidas de AES realizadas foram: velocidade sistólica de pico, índice de pulsatilidade e forma da onda de velocidade de fluxo. Essas foram comparadas em cada paciente no pré e pós-tratamento (com intervalos de 3 meses) para diagnóstico de perviedade. RESULTADOS: Medidas realizadas no pós-operatório nas artérias imediatamente distais aos segmentos tratados mostraram aumento consistente de velocidade sistólica de pico e índice de pulsatilidade com mudanças na forma da onda de velocidade de fluxo de unifásica para bi ou trifásica. A velocidade sistólica de pico e o índice de pulsatilidade aumentaram respectivamente em 92,26 e 98,2% (tratamentos no segmento aorto-ilíaco), em 112,83 e 62,39% (tratamentos no segmento fêmoro-poplíteo) e em 149,08 e 28,8% (tratamentos no segmento poplíteo-tibial). Tais mudanças nos padrões de velocidade de fluxo ocorreram em todos os pacientes e permaneceram quase inalteradas enquanto os tratamentos estivessem pérvios. Quando ocorria falência nos tratamentos (oclusões ou estenoses hemodinamicamente significantes), os parâmetros caíam a níveis similares aos de antes do tratamento. Se a falência do tratamento era corrigida por nova revascularização (enxerto ou angioplastia), os parâmetros de AES voltavam a se comportar como após o tratamento inicial. CONCLUSÃO: A AES pode ser usada no seguimento dos pacientes com revascularização dos membros devido a doença arterial oclusiva periférica, demonstrando tanto a perviedade quanto a falência do tratamento.