Application of poly aluminum chloride and alum as catalyst in catalytic ozonation process after coagulation for the treatment of textile wastewater.

Textile wastewater is ranked highly contaminated among all industrial waste. During textile processing, the consumption of dyes and complex chemicals at various stages makes textile industrial wastewater highly challenging. Therefore, conventional processes based on single-unit treatment may not be sufficient to comply with the environmental quality discharge standards and more stringent guidelines for zero discharge of hazardous chemicals (ZDHC). In this study, a novel approach was followed by recycling Poly aluminum chloride (PACl) and Alum as a catalyst for the first time in the catalytic ozonation treatment process leading to a nascent method after using them as a coagulant in Coagulation/Flocculation. In the current investigation, six different combinations were studied to remove turbidity, TSS, COD, BOD5, color, and biodegradability (BOD5/COD ratios) of wastewater. Moreover, Central Composite Design was implied using RSM in Minitab software. During the combination of treatment processes, it was found that the pre-coagulation/flocculation with coagulant PACl followed by post-catalytic ozonation with recycled PACl, a more effective treatment than others. The optimum R.E of turbidity, TSS, COD, and color were 84%, 86%, 89%, and 98%, respectively. Moreover, a decrease in toxicity and increase in biodegradability (BOD5/COD ratio from 0.29 to 0.54) was observed as well. The electrical energy demand and operational costs of treatment processes were estimated and compared with other treatment processes.

A Comprehensive Review on Zeolite Chemistry for Catalytic Conversion of Biomass/Waste into Green Fuels.

Numerous attempts have been made to produce new materials and technology for renewable energy and environmental improvements in response to global sustainable solutions stemming from fast industrial expansion and population growth. Zeolites are a group of crystalline materials having molecularly ordered micropore arrangements. Over the past few years, progress in zeolites has been observed in transforming biomass and waste into fuels. To ensure effective transition of fossil energy carriers into chemicals and fuels, zeolite catalysts play a key role; however, their function in biomass usage is more obscure. Herein, the effectiveness of zeolites has been discussed in the context of biomass transformation into valuable products. Established zeolites emphasise conversion of lignocellulosic materials into green fuels. Lewis acidic zeolites employ transition of carbohydrates into significant chemical production. Zeolites utilise several procedures, such as catalytic pyrolysis, hydrothermal liquefaction, and hydro-pyrolysis, to convert biomass and lignocelluloses. Zeolites exhibit distinctive features and encounter significant obstacles, such as mesoporosity, pore interconnectivity, and stability of zeolites in the liquid phase. In order to complete these transformations successfully, it is necessary to have a thorough understanding of the chemistry of zeolites. Hence, further examination of the technical difficulties associated with catalytic transformation in zeolites will be required. This review article highlights the reaction pathways for biomass conversion using zeolites, their challenges, and their potential utilisation. Future recommendations for zeolite-based biomass conversion are also presented.

Hand washing behavior change effect of community-based hygiene and sanitation intervention in low resource setting.

BACKGROUND: Lack of hygiene and sanitation causes significant disease, disability and death. Majority of diarrheal diseases are related to hygiene and drinking water. Hand washing with soap after toilet use and before eating reduces these risks significantly. METHODS: This report is based on a behavior change project in the rural community setting (union council Nahqi), Peshawar, Pakistan aimed to improve hygiene- and sanitation-related behavior. A pre-intervention survey was conducted at household level (n = 958), followed by a structured behavior change communication program with motivational and educational material and key health messages for three months. Lastly, an end-line survey was conducted measuring change in practice domains. RESULTS: All the domains of hygiene and sanitation showed statistically significant improvement (11-59% P < 0.001), including handwashing before meals (28.2%), before cooking (54.1%), before child feeding (21.2%), after defecation (30.6%); tooth brushing twice daily (7.3%); nail clipping at least weekly (16.3%); bathing daily (11.3%); change of clothing twice weekly (24.7%); covering the water containers (59.3%) and house orderliness (30.6%). CONCLUSION: The findings conclude that a behavior change communication program that is in accord with community needs, level of their understanding, beliefs and sociocultural norms is well received for positive behavior change.

Treatment of leachate through constructed wetlands using Typha angustifolia in combination with catalytic ozonation on Fe-zeolite A.

Leachate control and management is a major challenge faced during solid waste management as it may pollute surface and groundwaters. In the current research, constructed wetlands (CWs) vegetated with Typha angustifolia plant in combination with catalytic ozonation by ferrous (Fe)-coated zeolite A was studied for the treatment of leachate. The CWs treatment with 9 days detention reduced the chemical oxygen demand (COD) and biochemical oxygen demand (BOD) up to 75.81% and 69.84%, respectively. Moreover, total suspended solids (TSS), total dissolved solids (TDS), and total kjeldahl nitrogen (TKN) removal of 91.16%, 33.33%, and 25.22% were achieved, respectively. The Fe-coated zeolite A catalytic ozonation further reduced the COD up to 90.7%. Comparison of the processes showed the effective performance of the combined process (CW/O3/Fe-zeolite) with 97.76% COD reduction of leachate. It is, therefore, concluded that the studied combined process (CW/O3/Fe-zeolite A) was more efficient as compared with single ozonation and CW alone, hence it can be implied for the leachate treatment in real conditions.

Subcritical and supercritical water oxidation for dye decomposition.

The total annual output of synthetic dyes exceeds 7 × 105 tons. About 1,000 tons of non-biodegradable synthetic dyes are released every year into the natural streams and water sources from textile wastes. The release of these colored wastewater exerts negative impact on aquatic ecology and human beings because of the poisonous and carcinogenic repercussions of dyes involved in coloration production. Therefore, with a growing interest in the environment, efficient technologies need to be developed to eliminate dyes from local and industrial wastewater. Supercritical water oxidation as a promising wastewater treatment technology has many advantages, such as a rapid reaction and pollution-free products. However, due to corrosion, salt precipitation and operational problems, supercritical water oxidation process did not gain expected industrial development. These technical difficulties can be overcome by application of non-corrosive subcritical water as a reaction medium. This work summarizes the negative impacts of dyes and role of subcritical and supercritical water and their efficiencies in dye oxidation processes.

Public health education and health system needs in Pakistan: a mixed methods study.

BACKGROUND: Pakistan has recently observed a significant growth in public health education programmes. Little is known about the structure of these programmes nor whether they are adequately responsive to national health system needs. AIMS: We reviewed existing public health degree programmes in Pakistan along with an exploration of the national public health market and health system needs. METHODS: A mixed-methods study was conducted between January 2015 and March 2016. Seventeen public health degree programmes were reviewed for programmatic and instructional attributes. Thirteen key-informant interviews were conducted to explore health system needs and challenges related to public health workforce. RESULTS: We found substantial variation in public health academic programmes in terms of offered courses, credit hours, number of faculty and tuition costs. About 70% of public health degree programmes were generic (i.e. with no specific concentration track) and only 18% offered practicums. Overall median tuition cost in 2016 was US$ 10 350. During key-informant interviews, emerged themes for challenges included lack of practical public health skills, limited knowledge of latest theoretical principles, poor communication skills and insufficient IT orientation. Identified themes about knowledge and skills areas to address future public health challenges of Pakistan included system thinking mind set, healthcare IT skills, and leadership and management skills. CONCLUSIONS: Public health education in Pakistan falls short of meeting current national challenges. Pakistan needs a national public health accreditation body for regulating education, harmonizing global standards to local context and developing relevant career pathways.

Practice and enforcement of national Hospital Waste Management 2005 rules in Pakistan.

BACKGROUND: Hospital waste management (HWM) rules in Pakistan were issued in 2005. Despite a decade of enactment, adherence to HWM 2005 rules has been inconsistent and systematic assessment of adherence using a World Health Organization (WHO)-recommended questionnaire has not been done in all teaching hospitals of Peshawar District. AIMS: This study assessed the adherence to HWM 2005 rules by tertiary care teaching hospitals of Peshawar District with respect to HWM personnel, policy and practices. METHODS: Pretested structured questionnaires based on WHO recommendations were used to survey all teaching hospitals of Peshawar District from January to March 2015. Data were also collected on HWM infrastructure and processes from 1 randomly selected medical, surgical, paediatric, and obstetrics/gynaecology unit in each hospital. Besides descriptive statistics, public and private hospitals were compared using Fisher's exact and Wilcoxon rank-sum tests. RESULTS: Most surveyed hospitals lacked formal HWM plans (70%), written procedures (80%), related job descriptions (80%) or records (90%). Many hospitals neither had trained HWM supervisors (56%) nor did they organize formal HWM trainings for new staff (40%). None of the hospitals followed waste segregation and colour coding. When compared to national HWM 2005 rules, multiple gaps in appropriate transportation, storage and disposal were found with no statistically significant difference between public and private hospitals. CONCLUSIONS: Serious gaps in adherence to HWM 2005 rules exist in surveyed hospitals. With recent devolution of environmental function, the Government of Khyber Pakhtunkhwa should enact provincial HWM rules (and ensure their implementation) to facilitate effective HWM practice across provincial healthcare facilities.

One-Step In Situ Growth of Iron-Nickel Sulfide Nanosheets on FeNi Alloy Foils: High-Performance and Self-Supported Electrodes for Water Oxidation.

Efficient and durable oxygen evolution reaction (OER) catalysts are highly required for the cost-effective generation of clean energy from water splitting. For the first time, an integrated OER electrode based on one-step direct growth of metallic iron-nickel sulfide nanosheets on FeNi alloy foils (denoted as FeNi3 S2 /FeNi) is reported, and the origin of the enhanced OER activity is uncovered in combination with theoretical and experimental studies. The obtained FeNi3 S2 /FeNi electrode exhibits highly catalytic activity and long-term stability toward OER in strong alkaline solution, with a low overpotential of 282 mV at 10 mA cm-2 and a small Tafel slope of 54 mV dec-1 . The excellent activity and satisfactory stability suggest that the as-made electrode provides an attractive alternative to noble metal-based catalysts. Combined with density functional theory calculations, exceptional OER performance of FeNi3 S2 /FeNi results from a combination of efficient electron transfer properties, more active sites, the suitable O2 evolution kinetics and energetics benefited from Fe doping. This work not only simply constructs an excellent electrode for water oxidation, but also provides a deep understanding of the underlying nature of the enhanced OER performance, which may serve as a guide to develop highly effective and integrated OER electrodes for water splitting.

Bovine carotid artery biologic graft outperforms expanded polytetrafluoroethylene for hemodialysis access.

OBJECTIVE: Arteriovenous grafts remain reliable substitutes for permanent hemodialysis access in patients without a suitable autogenous conduit. Advances in conduit design and endovascular management of access-related complications question the preference for synthetic conduits over biologic grafts in contemporary practice. In this study, we compared outcomes between a bovine carotid artery (BCA) biologic graft and expanded polytetrafluoroethylene (ePTFE) grafts for hemodialysis access in a recent cohort of patients. METHODS: This was a single-institution retrospective review of 120 consecutive grafts placed in 98 patients between January 1, 2011, and June 30, 2014. Univariate methods (χ2, analysis of variance, t-test) were used to compare demographic and medical characteristics of patients who received each graft type. Kaplan-Meier, log-rank tests, univariate and multivariate logistic analyses, and Cox regression analyses were used to evaluate patency and graft complications. Outcomes were defined and analyzed according to reporting guidelines published by the Society for Vascular Surgery. RESULTS: Of the 120 grafts studied, 52 (43%) were BCA and 68 (57%) were ePTFE. Successful graft use for dialysis was 96% (95% confidence interval [CI], 90%-100%) for BCA and 84% (95% CI, 74%-93%) for ePTFE (P = .055). Comparing BCA vs ePTFE, estimates for primary patency were 30% vs 43% at 1 year and 16% vs 29% at 2 years (P = .27). Primary assisted patency was 36% vs 45% at 1 year and 24% vs 35% at 2 years (P = .57). Secondary patency was 67% vs 48% at 1 year and 67% vs 38% at 2 years (P = .05). There were no differences in primary (hazard ratio [HR], 0.70; 95% CI, 0.40-1.28; P = .25) and primary assisted (HR, 0.87; 95% CI, 0.46-1.65; P = .67) patency for BCA compared with ePTFE. However, secondary patency was higher for BCA compared with ePTFE (HR, 2.92; 95% CI, 1.29-6.61; P = .01). Graft infection rates during the study period were 15.4% for BCA and 20.6% for ePTFE (P = .47). The significant predictors of graft failure were higher body mass index (HR, 1.06; 95% CI, 1.00-1.11; P = .04) and hyperlipidemia (HR, 2.94; 95% CI, 1.27-6.76; P = .01). CONCLUSIONS: In this study of a recent cohort of patients who received arteriovenous grafts, primary and primary assisted patencies were similar between BCA and ePTFE grafts. However, secondary patency was higher for BCA, indicating better durability for the biologic graft than for ePTFE grafts in patients whose anatomy preclude placement of an arteriovenous fistula.

Abdominal aortic aneurysm repair in octogenarians is associated with higher mortality compared with nonoctogenarians.

OBJECTIVE: Age is a well-known independent risk factor for death after abdominal aortic aneurysm (AAA) repair. However, there is significant debate about the utility of AAA repair in older patients. In this study, mortality outcomes after endovascular AAA repair (EVAR) and open AAA repair (OAR) in octogenarians (aged ≥80 years) were compared with younger patients (aged <80 years). METHODS: All patients recorded in the Vascular Quality Initiative database (2002-2012) who underwent infrarenal AAA repair were included. Univariable and multivariable statistics were used to compare perioperative (30-day) and 1-year mortality outcomes between octogenarians vs nonoctogenarians for OAR and EVAR. RESULTS: During the study period, 21,874 patients underwent AAA repair (OAR, 5765; EVAR, 16,109), including 4839 octogenarians (OAR, 765; EVAR, 4074) and 17,035 nonoctogenarians (OAR, 5000; EVAR, 12,035). Octogenarians (mean age, 83.0 ± 0.1 years) were less frequently male (66% vs 75%) and had a higher prevalence of congestive heart failure (9.9% vs 7.1%), chronic renal insufficiency (12.2% vs 7.5%), and a history of aortic surgery (14.3% vs 7.7%) compared with nonoctogenarians (P < .01 for all). Intraoperative use of blood transfusions and vasopressors was more common in octogenarians for OAR (blood: 3.3 ± 4.4 vs 1.8 ± 3.7 units; vasopressors: 45.2% vs 32.8%) and EVAR (blood: 0.43 ± 1.7 vs 0.31 ± 1.6 units; vasopressors: 7.6% vs 5.7%; P < .01 for all). Contrast dye volumes used during EVAR were similar in octogenarians and nonoctogenarians (108 ± 71 vs 107 ± 68 mL; P = .18). Perioperative mortality after OAR was 20.1% in octogenarians compared with 7.1% in nonoctogenarians (P < .01). Perioperative mortality after EVAR was 3.8% in the octogenarians compared with 1.6% in nonoctogenarians (P < .01). One-year mortality among octogenarians vs nonoctogenarians was 26% vs 9.7% for OAR and 8.9% vs 4.3% for EVAR (log-rank test, P < .01 for both). Multivariable analysis controlling for baseline and intraoperative differences between groups demonstrated that age ≥80 years increased the risk of 30-day and 1-year mortality after AAA repair by 223% and 187%, respectively (P < .01 for both). CONCLUSIONS: AAA repair should be approached with extreme caution in octogenarians. Perioperative and 1-year mortality rates after OAR are particularly high in the older population, suggesting that the appropriate aneurysm size threshold for OAR might be larger due to the greater operative risk in octogenarian patients.

Beta-blocker use is associated with lower stroke and death after carotid artery stenting.

BACKGROUND: Proper selection of patients for carotid artery stenting (CAS) remains controversial despite multiple controlled trials. This relates in part to differences in interpretation of the relative importance of myocardial vs stroke complications after the procedure by different specialties and a lack of granular clinical data to analyze outcomes outside the large clinical trials. The objective of this study was to assess the effect of preoperative medications, procedure parameters, and patient characteristics on outcomes of CAS performed in a multispecialty national database. METHODS: We analyzed all patients who underwent CAS between 2005 and 2014 in the Vascular Quality Initiative. A multivariate logistic regression model was built to assess the effects of age, gender, comorbidities, smoking, preprocedure medications, procedure details, and hypotension or hypertension that required intravenous medication on 30-day death or stroke rates. RESULTS: A total of 5263 patients underwent CAS (mean age, 70 years; 63% male). The 30-day stroke/death rate was 3.4% (1.5% minor stroke, 0.9% major stroke, and 1.2% death; 40% of patients who had major strokes died within 30 days), and the myocardial infarction rate was 0.8%. Postprocedural hypertension requiring treatment occurred in 519 cases (9.9%), and it was associated with a 3.4-fold increase in stroke/death (odds ratio, 3.39; 95% confidence interval, 2.30-5.00; P < .0001). Preprocedural beta-blocker use for >30 days was associated with a 34% reduction in the stroke/death risk (odds ratio, 0.66; 95% confidence interval, 0.46-0.95; P = .025) compared with nonuse. Beta-blocker use was not associated with postprocedural hypotension. Other predictors of postoperative stroke and death included age, symptomatic status, diabetes (type 1 or type 2), and postprocedural hypotension, whereas prior carotid endarterectomy and distal embolic protection use were protective. CONCLUSIONS: Postprocedural hypertension and hypotension that require treatment are both strongly associated with periprocedural stroke/death after CAS. Beta blockers significantly reduce the stroke/death risk associated with carotid stenting and should be investigated prospectively for potential use during CAS.

Contemporary Outcomes for Open Infrainguinal Bypass in the Endovascular Era.

BACKGROUND: The role of infrainguinal bypasses in this era of increasing endovascular interventions remains the subject of significant debate. In this study, we evaluate contemporary long-term outcomes of lower-extremity open revascularization for peripheral arterial disease (PAD). METHODS: We evaluated all patients who underwent infrainguinal bypass with autogenous vein conduits for claudication or critical limb ischemia in our institution between January 1st, 2007 and July 31st, 2014. Kaplan-Meier and Cox regression analyses were used to evaluate graft failure and identify its predictors. Outcomes were defined per the Society for Vascular Surgery standards. RESULTS: There were 428 autogenous vein grafts (femoro-popliteal: 32%, femoro-tibial: 39%, popliteo-tibial: 27%, and tibio-tibial: 2%) placed in 368 patients (mean age of 67 ± 11.4 years). Most patients were male (59%), white (73%), and presented with critical limb ischemia (81%). Sixty-five cases (15%) were redo bypasses. Arm veins and spliced vein conduits were used in 15% and 14% of cases, respectively. Primary patency at 1, 3, and 5 years was 66%, 59%, and 55%, respectively. Primary-assisted patency was 78%, 69%, and 64% at 1, 3, and 5 years, respectively. Secondary patency was 88%, 84%, and 82% at 1, 3, and 5 years, respectively. Patency was higher for grafts harvested from the lower versus upper extremities and for proximal versus distal bypass (all P < 0.05). Limb salvage rate was 88% after a mean follow-up of 2 ± 1.8 years. Significant predictors of graft failure were younger age, diabetes mellitus, and hyperlipidemia (all P < 0.05). CONCLUSIONS: In this contemporary cohort of patients, we have demonstrated that infrainguinal bypass for lower-extremity revascularization has good long-term outcomes in patients with symptomatic PAD. Patency and limb salvage rates are optimized with careful selection of autogenous conduits, close monitoring of high-risk groups and management of comorbidities.

Highly efficient decomposition of Remazol Brilliant Blue R using tubular reactor coated with thin layer of PdO.

In this work, we propose a novel approach to dye decomposition under subcritical water conditions using a continuous-flow tubular reactor coated with thin layer of PdO as a catalyst. Remazole Brilliant Blue R was used as an example of synthetic dyes. Hydrogen peroxide was used as an environmental-friendly oxidant as it leaves no residues after treatment. The effect of temperature, pressure and dye concentration on total organic carbon (TOC) removal were studied. 99.9% of TOC removal was achieved at 300 °C and 10 MPa pressure within a short residence time of 3.2 s. This method provided an efficient and rapid process that has a potential for treating a wide range of textile wastewaters.

Effect of patching on reducing restenosis in the carotid revascularization endarterectomy versus stenting trial.

BACKGROUND AND PURPOSE: The purpose is to determine whether patching during carotid endarterectomy (CEA) affects the perioperative and long-term risks of restenosis, stroke, death, and myocardial infarction as compared with primary closure. METHODS: We identified all patients who were randomized and underwent CEA in Carotid Revascularization Endarterectomy versus Stenting Trial. CEA patients who received a patch were compared with patients who underwent CEA with primary closure without a patch. We compared periprocedural and 4-year event rates, 2-year restenosis rates, and rates of reoperation between the 2 groups. We further analyzed results by surgeon specialty. RESULTS: There were 1151 patients who underwent CEA (753 [65%] with patch and 329 [29%] with primary closure). We excluded 44 patients who underwent eversion CEA and 25 patients missing CEA data (5%). Patch use differed by surgeon specialty: 89% of vascular surgeons, 6% of neurosurgeons, and 76% of thoracic surgeons patched. Comparing patients who received a patch versus those who did not, there was a significant reduction in the 2-year risk of restenosis, and this persisted after adjustment by surgeon specialty (hazard ratio, 0.35; 95% confidence interval, 0.16-0.74; P=0.006). There were no significant differences in the rates of periprocedural stroke and death (hazard ratio, 1.58; 95% confidence interval, 0.33-7.58; P=0.57), in immediate reoperation (hazard ratio, 0.6; 95% confidence interval, 0.16-2.27; P=0.45), or in the 4-year risk of ipsilateral stroke (hazard ratio, 1.23; 95% confidence interval, 0.42-3.63; P=0.71). CONCLUSIONS: Patch closure in CEA is associated with reduction in restenosis although it is not associated with improved clinical outcomes. Thus, more widespread use of patching should be considered to improve long-term durability. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00004732.

Poststent ballooning is associated with increased periprocedural stroke and death rate in carotid artery stenting.

BACKGROUND: Whereas carotid endarterectomy (CEA) remains the "gold standard" treatment, given its low complication rate, carotid artery stenting (CAS) has emerged as a valid alternative in patients with prohibitive surgical risks. However, the application of CAS has been scrutinized, given its increased perioperative risk in comparison to CEA. Operators follow general guidelines in intraoperative techniques in CAS. However, few of those are evidence based. We believe that a specific outcome-driven examination of the effect of pre- and poststent deployment ballooning is warranted. The objective of this study was to analyze the effect of prestent ballooning (pre-SB) and poststent ballooning (post-SB) on hemodynamic depression (HD) and perioperative stroke or death. METHODS: We performed a retrospective analysis of all patients who had CAS between 2005 and 2014 in the Vascular Quality Initiative database. Logistic regression analyses of the effect of different pre-SB and post-SB combinations on HD and the 30-day stroke and death rate were performed. We excluded patients who had no protection device, those with isolated common carotid artery lesions, and those who had no ballooning at all. The models controlled for patient age, gender, comorbidities, smoking status, symptomatic status, history of previous ipsilateral CEA, preoperative medications, and ipsilateral degree of stenosis. RESULTS: A total of 3772 patients who underwent CAS were included for analysis. Average age of patients was 69.8 ± 9.6 years, with 63% being male. The overall perioperative stroke and death rate was 3.0%. Compared with pre-SB only technique, the combined pre-SB and post-SB technique had a 2.1-fold increase in HD (odds ratio, 2.13; 95% confidence interval, 1.51-3.01; P < .001) and 2.4-fold increase in perioperative stroke and death rate (odds ratio, 2.37; 95% confidence interval, 1.01-5.62; P < .050). CONCLUSIONS: Compared with pre-SB alone, the use of post-SB increases the chances of perioperative HD and stroke and death rate in patients undergoing CAS. Post-SB should be used only in those cases with severe residual stenosis.

Mortality variability after endovascular versus open abdominal aortic aneurysm repair in a large tertiary vascular center using a Medicare-derived risk prediction model.

OBJECTIVE: Previous reports have documented better outcomes after open abdominal aortic aneurysm (AAA) repair in tertiary centers compared with lower-volume hospitals, but outcome variability for endovascular AAA repair (EVAR) vs open AAA repairs in a large tertiary center using a Medicare-derived mortality risk prediction model has not been previously reported. In the current study, we compared the observed vs predicted mortality after EVAR and open AAA repair in a single large tertiary vascular center. METHODS: We retrospectively analyzed all patients who underwent repair of a nonruptured infrarenal AAA in our center from 2003 to 2012. Univariable and multivariable logistic regression were used to evaluate 30-day mortality. Patients were stratified into low-risk, medium-risk, and high-risk groups, and mortality was predicted for each patient based on demographics and comorbidities according to the Medicare risk prediction model. RESULTS: We analyzed 297 patients (EVAR, 72%; open AAA repair, 28%; symptomatic, 25%). Most of our patients were of high and moderate risk (48% and 28%, respectively). The observed 30-day mortality was 1.9% after EVAR vs 2.4% after open repair (odds ratio [OR], 0.77; 95% confidence interval [CI], 0.14-4.29; P = .67). There was no difference in mortality with EVAR vs open repair after adjusting for predefined patient characteristics (OR, 0.92; 95% CI, 0.16-7.43; P = .93); only preoperative renal disease was predictive of 30-day mortality after AAA repair in our cohort (OR, 8.39; 95% CI, 1.41-67.0). The observed mortality within our study was significantly lower than the Medicare-derived expected mortality for each treatment group within patients stratified as high risk or medium risk (P ≤ .0002 for all). CONCLUSIONS: Despite treating patients with high preoperative risk status, we report a 10-fold decrease in operative mortality for EVAR and open AAA repair in a tertiary vascular center compared with national Medicare-derived predictions. High-risk patients should be considered for aneurysm management in dedicated aortic centers, regardless of approach.

Mortality benefits of different hemodialysis access types are age dependent.

OBJECTIVE: Risk of death in dialysis patients is lowest with arteriovenous fistulas (AVFs), followed by arteriovenous grafts (AVGs) and then intravenous hemodialysis catheters (HCs). Our aim was to analyze the effects of age at hemodialysis initiation on mortality across different access types. METHODS: All patients ≥18 years in the United States Renal Data System between the years 2006 and 2010 were analyzed. Spline modeling and risk-adjusted Cox proportional hazard models were used to analyze the effect of age on mortality for first dialysis access with AVF vs AVG vs HC. RESULTS: The study analyzed 507,791 patients (63.4 ± 0.02 years; 56.5% male; 40.9% mortality; follow-up, 1.57 ± 1.36 years). Increasing age was a significant predictor of overall mortality (adjusted hazard ratio [aHR], 1.03; P < .001). Compared with patients with HCs (n = 418,932), overall risk-adjusted mortality was lowest in patients with AVFs (n = 71,316; aHR, 0.63; P < .001) followed by AVGs (n = 17,543; aHR, 0.83; P < .001). AVF was superior to both HC and AVG for all age groups (P < .001). However, there was a significant change in the relative efficacy of AVG at ages 48 years and 89 years based on spline modeling; there were no significant differences comparing adjusted mortality with AVG vs HC for patients aged 18 to 48 years or for patients >89 years, but AVG was superior to HC for patients 49 to 89 years of age (aHR, 0.811; P < .001). The mortality benefit of AVF was consistently superior to that of AVG and HC for patients of all ages (all, P < .001). CONCLUSIONS: AVF is superior to AVG and HC regardless of the patient's age, including in octogenarians. In contrast, the mortality benefit of AVG over HC may not apply to younger (18-48 years) or older (>89 years) age groups. All patients 18 to 48 years should receive AVF for dialysis access whenever possible.

Performance of the Aorfix endograft in severely angulated proximal necks in the PYTHAGORAS United States clinical trial.

OBJECTIVE: This study compared the performance of the Aorfix endograft (Lombard Medical, Oxfordshire, United Kingdom) in standard (<60°), highly angled (60°-90°), and severely angled (>90°) aortic necks in the PYTHAGORAS study and evaluated changes in neck morphology over time. METHODS: PYTHAGORAS is a prospective nonrandomized clinical trial of the Aorfix endograft. We divided the endovascular aneurysm repair (EVAR) cohort into groups by standard, high, and severe neck angle. The primary control group was patients concurrently undergoing open repair. Mortality at 30 days, 1 year, and 2 years and 30-day freedom from Society for Vascular Surgery major adverse events for the EVAR groups was compared with the open control. Aneurysm sac change, type I and III endoleaks, graft migration, and the reintervention rate at 1 and 2 years was compared between the standard, highly, and severely angled populations. The relative risk of graft complications with a neck diameter increase >10% was also calculated. At predetermined anatomic points, the effect of oversizing on aortic diameter was evaluated by calculating oversize percentage ([1 - outer aortic diameter measured at a given time/stent graft diameter] × 100%) preoperatively and at 3 years. In addition, the average oversizing percentage at 30 days and annually at 1 to 5 years was compared with the preoperative oversizing percentage. Finally, complication rates with ≥30% vs <30% planned oversizing were compared. RESULTS: The adverse event rate was lower for every EVAR group than the open control. In addition, the mortality rates at 30 days, 1 year, and 2 years were similar between the standard-angle (1.5%, 3.0%, 4.5%), high-angle (0.9%, 7.3%, 13.8%), and severe-angle (4.8%, 9.5%, 14.3%) EVAR groups and the open control groups (1.3, 6.6%, 10.5%). At 1 and 2 years, there was no difference in graft complications among the EVAR groups. However, with neck dilatation of >10% at 5 mm above the proximal renal and 1 mm below the distal renal, there was an increased risk of graft migration (relative risk, 4.38 [P = .01] and 4.33 [P = .002], respectively). For all predetermined anatomic points, the oversizing percentage decreased over time. The rate of oversize percentage decrease was faster at more distal aortic locations, reaching <10% at 30 days 15 mm below the renal, at 2 years 7 mm below the renal, and at 5 years 1 mm below the renal (P < .001 for all). Half the oversize percentage achieved at the index procedure remained at 3 years (Pearson correlation coefficient = 0.5). However, there was no difference in complications between the ≥30% and <30% planned oversize groups. CONCLUSIONS: The Aorfix endograft has performed well in excluding aneurysms with standard and highly angled aortic neck anatomy.

Limitation of imaging in identifying iatrogenic aortic coarctation following thoracic endovascular aortic repair.

A 21-year-old male suffered blunt trauma from a motor vehicle accident causing thoracic aorta tear. The smallest available stent graft was deployed. Definitive repair was later performed using a 22 × 22 × 116 mm Talent Thoracic Stent Graft. The postoperative course was uneventful. Seventeen months later, he presented with dizziness, chest pain, acute renal failure, malignant hypertension, and troponin elevation. Computed tomography (CT) angiogram and transesophageal echocardiogram did not reveal any dissection, stent stenosis or collapse. Cardiac catheterization showed normal coronary arteries but a 117 mm Hg gradient across the stent graft. Iatrogenic coarctation of the aorta was confirmed with a second measurement during arch angiogram. A Palmaz stent was deployed over the distal end of the previous stent graft with complete resolution of symptoms and gradual normalization of kidney function. This case report demonstrates a need for wider availability and selecting appropriate stent graft in treating traumatic aortic injuries in young patients. It is the first case report of the inability of current imaging modalities in confirming stent collapse. Pressure gradient is a useful tool in confirming stent collapse when clinical scenario does not match CT findings.

The age effect in increasing operative mortality following delay in elective abdominal aortic aneurysm repair.

BACKGROUND: Elective repair of large abdominal aortic aneurysms (AAAs) is associated with the risk of significant perioperative mortality. When abdominal aneurysm repair is delayed, patients with asymptomatic large AAAs face the risk of death from rupture. In addition to the risk of rupture, the advancing age of the patients adds a future operative risk. This risk has been historically documented in age groups. However, a more accurate representation of the increasing operative risk with age is needed. METHODS: We analyzed all patients in the American College of Surgeons National Surgical Quality Improvement Program database who underwent endovascular or open repair for asymptomatic infrarenal AAA between 2005 and 2012. Multivariable logistic regression was used to evaluate the effect of increasing age and operative delay on 30-day postoperative mortality. RESULTS: There were 27,576 patients who underwent AAA repair during the study period (mean age 73.5 years, standard deviation 8.6, 80% male, 24% open repair). There was a linear relative increase of 5% (odds ratio [OR] 1.05, 95% confidence interval [CI] 1.04-1.06, P < 0.001) in the odds of operative death after AAA repair with each year of operative delay irrespective of treatment approach. There was a linear relative increase of 4% for endovascular aneurysm repair (OR 1.04, 95% CI 1.02-1.05, P < 0.001) and 6% for open repair (OR 1.06, 95% CI 1.04-1.08, P < 0.001) with each year of delay in repair. CONCLUSIONS: Because of increasing age, delay in surgery is associated with uniform increase in the risk of perioperative mortality in asymptomatic patients who meet criteria for AAA repair. It is important for surgeons to incorporate this more accurate estimation of operative risk into discussions with patients who qualify for treatment yet decide to forgo surgery for the repair of their AAA.