Arteriovenous Graft Infection Research Articles

Rerouting bei Infektionen des vaskulären Zugangs unter Verwendung eines biosynthetischen Gefäßtransplantats (Omniflow® II)

Abstract Background Surgical treatment of infected arteriovenous grafts (AVG) while preserving the hemodialysis access remains a challenge. Partial graft excision (PGE) directly followed by interposition grafting (IG) is an established method but is associated with a high rate of local reinfection. This retrospective study investigated the technique of rerouting using a biosynthetic vascular graft (Omniflow® II). Methods This was a retrospective analysis of all patients at a tertiary referral center undergoing surgical treatment for AVG infections using PGE and IG with the rerouting technique using Omniflow® II between January 2009 and December 2018. Follow-up data were collected until May 2021. Results Fifteen patients (53% male, median age 62 years [range 49-81]) were identified for further analysis, thereof twelve received an Omniflow® II vascular graft. Eleven patients had positive local microbial cultures, with Staphylococcus aureus being the most frequently identified pathogen (9 cases). Mortality and reoperation rates within 30 days were both 0%. Median follow-up was 32 months (range 2–101 months) with a median follow-up index of 0.92 (range 0.18–1). During follow-up a surgical intervention for reinfection was necessary in 3 patients with Omniflow® II at a median of 304 days (range 298–485 days). Conclusion Partial graft excision and direct interposition grafting using a biosynthetic Omniflow® II vascular graft is a valid treatment option in selected patients with AVG infections when total graft excision can be avoided. Using a careful rerouting technique, while preserving clinically noninfected graft sections the risk of early reinfection can be minimized and the dialysis access maintained.

Management of infected arteriovenous grafts for haemodialysis: Outcomes and strategies using a novel objective scoring system.

In haemodialysis patients with exhausted autogenous options, prosthetic arteriovenous grafts (AVGs) are frequently utilised as tertiary vascular access. However, the prosthetic nature of AVGs precipitates an increased risk of infection which may translate to excess morbidity and life-threatening complications. The current evidence remains divided on the optimal treatment strategy for arteriovenous graft infections (AVGi) with arguments for conservative management by antibiotics, salvaging with graft revision or total/subtotal excision. To address this gap, we assessed the outcomes of AVGi patients treated in our institution, developing an AVGi severity classification model and a proposed treatment algorithm to guide AVGi management. We conducted a single centre retrospective review of outcomes of patients with AVGi managed either by sole antibiotics therapy, graft revision or surgical excision between June 2016 and May 2021. Outcomes of AVGi patients across differing treatment groups were compared, including 1-year mortality, 6-month and 1-year functional vascular access. We also analysed the outcomes of tunnelled haemodialysis lines (THL), which were used as a temporary vascular access in several AVGi patients in our study. A total of 34 AVGi patients were managed within that time frame and included in the study (5 conservatively management by antibiotics, 5 graft revisions and 24 surgical excision) with a mean age of 60.4 ± 14.4 years (67.6% males). Overall 1-year mortality was 14.7%. A 6-month functional vascular access status across the three groups stood at 60%, 60% and 10% while 1-year functional vascular access status was 60%, 75% and 42% respectively. When clinically appropriate, conservative management by antibiotics or salvage/graft revision can present as prudent AVGi treatment options. The adoption of our proposed severity classification system and treatment algorithm provides a more thorough objective assessment of the infection and helps guide the clinical decision-making process.

Management of Arteriovenous Graft Infection.

Objective: Arteriovenous graft (AVG) infection influences the survival and quality of life of patients, causing life-threatening sepsis reducing dialysis access. This study aimed to evaluate an appropriate treatment strategy for AVG infection. Methods: We analyzed 61 cases involving AVG infections identified at a single center. The cases were divided into two groups based on the type of AVG and surgical methods, namely, currently used AVG (cAVG) (n=29) or abandoned AVG (aAVG) (n=32) and total graft excision (TGE) (n=10) or partial graft excision (PGE) (n=46). Results: There was a significant difference in lower procedure frequency (p<0.001) and longer procedure time (p=0.014) in the cAVG group. A significant difference in lower reinfection rate (p=0.009) was found in the TGE group. Multivariable analysis confirmed that aAVG significantly independently affected the reinfection rate (hazard ratio, 2.208; 95% confidence interval, 1.069-4.561; p=0.032). Staphylococcus aureus was the most frequent cause of AVG infection (61.5%); 77.5% of Staphylococcus aureus were methicillin-resistant Staphylococcus aureus. Conclusion: We found a higher risk of reinfection after PGE than TGE, and aAVG infection was associated with approximately two times higher likelihood of reinfection. These findings suggest that TGE should be considered for patients with AVG infections, particularly aAVG infections.

Meta-analysis of total versus partial graft excision: Which is the better choice to manage arteriovenous dialysis graft infection?

Arteriovenous graft infection (AVGI) is a major cause of hemodialysis access failure. Delayed diagnosis and inappropriate treatment may lead to increased morbidity (3-35%) and mortality up to 12%. Compare the postoperative outcomes of total graft excision (TGE) and partial graft excision (PGE) in the treatment of AVGI. Systematic review and meta-analysis METHODS: The dataset was defined by searching PubMed, EMBASE, Google Scholar, and the Cochrane database for articles outlining the terms arteriovenous graft infection, infected dialysis graft, TGE and PGE published between 1995-2020. The data analysis evaluated the outcomes of TGE and PGE in the management of AVGI. The meta-analysis was performed using Review Manager Software version 5.4.1. 30-day mortality, recurrent infection, and reoperation rate. Eight studies, including 555 AVGI, and 528 patients. PGE showed a significant increase in recurrent graft infection rate (OR=0.23,95% CI=0.13-0.41, P<.00001) and re-operation rate for control of infection (OR=0.14,95% CI=0.03-0.58, P<.007). However, the 30-day mortality rate did not differ significantly between the groups (OR=0.92,95% CI=0.39-2.17, P=.85). TGE remains a safe and effective surgical method for the management of AVGI. PGE is associated with a higher risk of graft infection and need for re-operation. As a result, PGE should only be considered in carefully selected patients. Risk of bias due to the differences in patient characteristics. None.

528 A Single-Centre Retrospective Study in a Large Tertiary Renal Centre on the Management of Infected Arteriovenous Grafts

Abstract Aim Prosthetic arteriovenous grafts (AVGs) are often used as tertiary vascular access for haemodialysis in patients with exhausted autogenous options. AVGs are associated with an increased risk of infection which can lead to excess morbidity and life-threatening complications. Infected AVGs are challenging to manage, and the current evidence remains unclear on optimal strategy with arguments for conservative management, salvaging with revision or surgical excision (subtotal or total). This study sought to evaluate the management of infected AVGs by examining the clinical outcomes of patients with infected AVGs managed in our institution. Method We conducted a single-centre retrospective study of all AVG infections managed (conservative management via antibiotics; graft revision; surgical excision) in a large tertiary renal centre between June 2016 to May 2021. Primary outcome was mortality at 1 year. Secondary outcome was functional vascular access at 6 months and 1 year. Data were extracted from electronic patient records, radiology imaging and reporting. Results 34 patients were included in our study (14.7% conservatively managed; 14.7% revision; 70.6% surgical excision) with a mean age of 60.4 ± 14.4 years (67.6% males). Average time from AVG placement to presentation was 11.8 months. 1 year mortality was 14.7%. Functional vascular access at 6 months in the three groups was 60%, 60% and 10% and 1-year functional vascular access was 60%, 75% and 42% respectively. Conclusion Surgically excised infected AVGs are associated with poor 6-month and 1-year vascular access outcomes. The findings suggest that conservative management and/or revision are more prudent given their higher probability of subsequent functional access.

O061 A single-centre retrospective study in a large tertiary renal centre on the management of infected arteriovenous grafts

Abstract Introduction Prosthetic arteriovenous grafts (AVGs) are often used as tertiary vascular access for haemodialysis in patients with exhausted autogenous options. AVGs are associated with an increased risk of infection which can lead to excess morbidity and life-threatening complications. Infected AVGs are challenging to manage, and the current evidence remains unclear on optimal strategy with arguments for conservative management, salvaging with revision or surgical excision (subtotal or total). This study sought to evaluate the management of infected AVGs by examining the clinical outcomes of patients with infected AVGs managed in our institution. Methods We conducted a single-centre retrospective study of all AVG infections managed (conservative management via antibiotics; graft revision; surgical excision) between June 2016 to May 2021. Primary outcome was mortality at 1 year. Secondary outcome was functional vascular access at 6 months and 1 year. Data were extracted from electronic patient records, radiology imaging and reporting. Results 34 patients were included in our study (14.7% conservatively managed; 14.7% revision; 70.6% surgical excision) with a mean age of 60.4 ± 14.4 years (67.6% males). Average time from AVG placement to presentation was 11.8 months. 1 year mortality was 14.7%. Functional vascular access at 6 months in the three groups was 60%, 60% and 10% and 1-year functional vascular access was 60%, 75% and 42% respectively. Conclusion Surgically excised infected AVGs are associated with poor 6-month and 1-year vascular access outcomes. The findings suggest that conservative management and/or revision are more prudent given their higher probability of subsequent functional access. Take-home message Provision of a definite vascular access within the first year of graft infection is highly challenging. As such, conservative management and graft revision present as superior options to manage infected arteriovenous grafts.

Long‒term administration of tedizolid for spinal epidural abscesses due to an arteriovenous graft infection and MRSA sepsis： A case report

Long‒term administration of tedizolid for spinal epidural abscesses due to an arteriovenous graft infection and MRSA sepsis： A case report

A Case of a Patient Who Successfully Achieved Early Wound Closure by Local Negative Pressure Wound Therapy (NPWT) against Compromised Wound Healing after Arterio-Venous Graft Infection

The primary treatment strategy for arterio-venous graft (AVG) infection includes appropriate antibiotic use and removal of the infected graft. It is well known that patients with hemodialysis are likely to experience compromised wound healing, which often leads to various postoperative complications. Negative pressure wound therapy (NPWT) is a non-invasive procedure that promotes wound healing by sealing the wound under negative pressure. Although NPWT is practically accepted in general surgery, there are only a few reports of this strategy to the vascular access operation for patients with hemodialysis due to the possibility of severe bleeding. In the present report, we report a case of a patient who successfully achieved safe and early wound closure by NPWT against compromised wound healing after AVG infection.

Recurrent Pseudomonas aeruginosa Bacteremia

Introduction As part of an institutional review board–approved quality improvement project reviewing 10 years of experience (2009–2018) with Pseudomonas aeruginosa bacteremia (PAB) at our institution, we identified 15 patients with recurrent Pseudomonas bacteremia. Because recurrent P. aeruginosa bacteremia (RPAB) is uncommon, we reviewed our patients with PAB to evaluate its occurrence, epidemiology, clinical characteristics, and outcomes of care. Methods This was an institutional review board–approved quality improvement project. We reviewed the medical records of all patients with PAB from January 1, 2009, to December 31, 2018, and identified the subset of patients with RPAB. We report the incidence, epidemiology, source of bacteremia, comorbid conditions, treatment, and outcome for patients with RPAB. We compare these data to previously published series of PAB patients with RPAB. Results We identified 268 episodes of PAB. One patient with 6 occurrences of PAB secondary to injection drug use–associated tricuspid valve endocarditis was excluded because of noncompliance with therapy. This left 262 episodes of PAB for evaluation. Fifteen patients had a total of 19 episodes of RPAB: 13 patients had 2 episodes (1 recurrence each), 1 patient had 3 episodes (2 recurrences), and 1 patient had 5 episodes (4 recurrences). The recurrence rate was 7.3% (19/262). The mean and median ages for patients with RPAB were 59 and 58 years, respectively. The time between episodes of PAB ranged from 26 to 688 days with a mean and median of 166 and 97 days, respectively. There were 3 patients (16%) with different sources of bacteremia for consecutive episodes of PAB: 1 with neutropenic sepsis followed by acute mastoiditis, 1 with cellulitis of the leg followed by an infected sacral pressure ulcer, and 1 with pneumonia and then an infected arteriovenous graft. The source of the recurrent episode was the same as the prior episode in 16 instances (84%): (1) skin and soft tissue infection (7 episodes), (2) central venous catheter infection (3 episodes), (3) genitourinary infection (2 episodes), (4) pneumonia (1 episode), (5) infected aortic vascular graft (1 episode), (6) obstructive cholangitis (1 episode), and (7) primary bacteremia (1 episode). All but 2 patients had multiple comorbid conditions, and all but 1 patient with RPAB had ≥1 of 5 risk factors for PAB as reported in the literature. Six (32%) of 19 episodes of RPAB resulted in death. Five of 6 patients with fatal RPAB received appropriate antimicrobial therapy at the initial presentation to the hospital for the second/fatal episode. Infectious disease consultation was obtained in all but 1 episode of RPAB. Conclusions Recurrent PAB accounted for 19 (7.3%) of 262 episodes of PAB in our 10-year study. It was associated with multiple comorbid conditions. The recurrent episode was usually from the same source as the prior episode of PAB. Sources of RPAB were diverse (as discussed previously), and mortality was 32% despite appropriate antipseudomonal antimicrobial therapy in all but 1 episode of those who died. We review the literature for patients with RPAB and compare these patients with those in our patient population.

Application and implications of a standardised reporting system for arteriovenous access graft infection.

The perception that arteriovenous graft infection (AVGi) is frequent and severe is not based on contemporary data from large units using modern AVG. Furthermore, older reports compounded misperceptions by using non-standardised reporting that prevents easy comparison against the alternative modalities. The aim of this article is to use a recently published reporting scheme to analyse the frequency, management and outcome of AVGi in a large series of sequential early-cannulation AVG with long-term follow-up. A single-center series analysis was performed of 277 early-cannulation AVG with minimum 1-year follow-up (total 120,082 days). Infections relating to the AVG were classified, root-cause analysed and the outcomes presented. Sixteen percent of all AVG implanted (51 episodes) developed infection related to the AVG. Primary AVGi (related to the insertion procedure or within 28 days) occurred in 9 (3%); secondary AVGi (related to AVG in use) occurred 33 times (rate 0.27/1000 haemodialysis days), at a mean of 382 days, and tertiary AVGi (in AVG no longer in use) occurred nine times. Only 1/3 of all AVGi led to bacteraemia, and ½ did not lead to loss of functional access. AVG infection is not common, caused a systemic infection in only one-third, did not lead to metastatic infection, and importantly, was treatable without loss of access in one-half of all cases. Using an objective system that discriminates between aetiology and outcome allows a more complete objective understanding of relative infection risks and outcomes for AVG that can inform discussions with patients requiring vascular access for haemodialysis.

Patency of ePTFE Arteriovenous Graft Placements in Hemodialysis Patients: Systematic Literature Review and Meta-Analysis.

Arteriovenous grafts (AVGs) are an appropriate option for vascular access in certain hemodialysis patients. Expanded polytetrafluoroethylene (ePTFE) has become the dominant material for such grafts, due in part to innovations in graft design and surgical interventions to reduce complications and improve patency rates. Comprehensive evidence syntheses have not been conducted to update AVG performance in an era in which both access choice and ePTFE graft functioning may have changed. We conducted a systematic review and meta-analysis summarizing outcomes from recent studies of ePTFE AVGs in hemodialysis, following PRISMA standards. Literature searches were conducted in multiple databases to identify observational and interventional studies of AVG patency and infection risk. Primary, primary-assisted, and secondary patency rates were analyzed at 6, 12, 18, and 24 months postplacement. Kaplan-Meier graft survival plots were digitized to recreate individual patient-level data. Patency rates were pooled using a random effects model. We identified 32 studies meeting our selection criteria that were published from 2004 through 2019. A total of 38 study arms of ePTFE grafts were included, representing 3381 AVG accesses placed. The mean primary, primary-assisted, and secondary patency rates at 1 year were 41% (95% CI, 35% to 47%), 46% (95% CI, 41% to 51%), and 70% (95% CI, 64% to 75%), respectively. Mean 24-month patency rates were 28% (95% CI, 22% to 33%), 34% (95% CI, 27% to 41%), and 54% (95% CI, 47% to 61%), respectively. A high degree of heterogeneity across studies was observed. Overall risk of infection was not consistently reported, but among available studies the pooled estimate was 9% per patient-year (95% CI, 6% to 12%). This meta-analysis provides an up-to-date estimate of the performance of ePTFE AVGs, within the context of improved graft designs and improved interventional techniques.

The safety of bovine tissue arterial repair in removal of infected prosthetic hemodialysis grafts.

More than 400,000 Americans require dialysis, and many receive it via a prosthetic arteriovenous graft. Infection of these grafts is rare, but associated with significant morbidity and mortality. The gold standard is total graft excision with arteriotomy closure. This was previously done with autologous vein, but bovine tissue offers a reasonable alternative. The objective of this article is to evaluate a community hospital experience with bovine tissue arterial repair after total graft excision of infected prosthetic arteriovenous graft. A retrospective review was performed of all cases of infected prosthetic arteriovenous graft removal with bovine tissue arterial repair was performed. Thirteen cases were identified. Presentation, location of graft, and causative organism were reviewed; outcomes including reoperation and mortality were recorded. Of the 13 patients, 12 (92%) had positive cultures of the graft, bloodstream, or wound. Methicillin-resistant Staphylococcus aureus was the most commonly isolated organism (54%). There were two unplanned reoperations including hematoma drainage and wound debridement within the first year. Over the 1-year follow-up period, 1 patient died for a mortality of 8%. There were no re-infections during follow-up. Prosthetic arteriovenous graft infection remains a difficult challenge and is associated with significant morbidity and mortality. It presents in a variety of ways, including within an old thrombosed graft. Over the last several years, the causative organism has increasingly become drug resistant. Treatment with total graft excision requires arteriotomy closure, and for this bovine tissue has been demonstrated to be a viable option.

Total Resection of Infected Peripheral Hemodialysis Grafts Has a Favorable Impact on Outcomes

Surgical resection could be an eradication treatment for patients with infected hemodialysis arteriovenous grafts (AVGs). This study aimed to investigate the outcomes of 3 surgical methods, including total resection, subtotal resection, and revision. The patients who underwent surgical excision of infected AVGs performed at a single center from August 2012 to March 2019 were retrospectively analyzed. The following 3 surgical methods were used in our study: revision, subtotal resection, and total resection. Patients' demographics, medical history, perioperative details, reconstruction time, and follow-up data were collected. The outcomes including perioperative complications (within 30days), mortality, reinfection rate of AVGs, with new access reconstruction or not, and the outcomes between reconstruction and nonreconstruction in the follow-up period were evaluated. Forty-one patients had infected AVGs in our study. Patients' mean age was 62years, and 65.9% of the patients were female. The mean duration from the time of diagnosis to the operation was 14.4days. Signs and symptoms at presentation included fever (51.2 %), swelling (43.9%), pain (58.5%), erythematous change (92.7%), and more severe features, such as altered consciousness (14.6%) and hypotension (12.2%). The pathological changes in the infected grafts included bleeding (29.3%), pus formation (73.2%), pseudoaneurysm (26.8%), and graft exposure (17.1%). Wound and graft cultures revealed an infectious etiology with fungi (7.3%), Pseudomonas aeruginosa (12.2%), Enterococcus spp. (2.4%), and Staphylococcus spp. (58.5%), with methicillin-resistant Staphylococcus aureus accounting for only 7.3%. Total resection, subtotal resection, and revision surgery were performed in 17.1%, 63.4%, and 19.5% of patients, respectively. Seven patients with complications required reoperation (17.1%), and adhesion ileus and hospital-acquired pneumonia occurred in only 2.4% and 7.3% of patients, respectively. During follow-up, most patients (82.9%) had reconstruction of the peripheral hemodialysis access with mean time of 64.3 (range: 21-92) days; mean time of use of new access was 90.5days; and mean time of removal of catheter was about 106.3days. Mortality rates in patients without and with reconstructed AV access during follow-up were 50% and 18%, respectively (P<0.004). Eight cases (19.5%) had recurrence of AV access infections during follow-up; of these, 2 had revision surgery and 6 had subtotal resection. However, no patient with total resection had recurrent infections. The total resection group had no recurrent infection compared to the subtotal and revision groups. In addition, patients with reconstruction of peripheral hemodialysis access had a low mortality rate during the follow-up period.

Arteriovenous Grafts' Types of Indications and Their Infection Rate

Arteriovenous graft infection is a well-known and frequent complication. The objective of this study was to compare infection rates of primary and secondary indicated arteriovenous grafts (AVGs). Retrospectively, we evaluated the indications for AVGs created at our institution which became infected. One hundred forty AVGs were evaluated. Of these AVGs, 33 (23.6%) were primary and 107 (76.4%) secondary indicated. Infection of a primary AVG was detected in 5 patients (15.2 %). Infection of a secondary AVG was detected in 30 patients (28.0%). Primary and secondary patency were significantly lower in patients with infected AVG (P=0.006; P=0.0001). The effect of diabetes mellitus and age on development of infection was not confirmed. Indications for AVG creation clearly influence the future risk of infection. If the indication to use the AVG is to correct a complicated arteriovenous fistula, the risk of infection is 2 times higher.

Risk assessment of significant upper extremity arteriovenous graft infection in the Vascular Quality Initiative

ObjectiveInfectious complications of arteriovenous grafts (AVGs) are a major source of morbidity. Our aim was to characterize contemporary risk factors for upper extremity AVG infection. MethodsThe Vascular Quality Initiative (2011-2018) was queried for all patients undergoing upper extremity AVG creation. AVG infection was classified as an infection treated with antibiotics, incision and drainage, or graft removal. Multivariable analyses were used to evaluate risk factors for short- and long-term AVG infection. ResultsOf 1758 upper extremity AVGs, 49 (2.8%) developed significant infection within 3 months, resulting in incision and drainage in 24% and graft removal in 76% of cases. None were managed with antibiotics alone in the study sample. Patients with significant AVG infection were more likely to be white, to be insured, to have a history of coronary artery bypass graft and intravenous (IV) drug use, to be undergoing a concomitant vascular procedure, and to be discharged on an anticoagulant. In multivariable analysis, significant AVG infection within 3 months was associated with IV drug use history (odds ratio [OR], 5; 95% confidence interval [CI], 1.75-14.3; P = .003), discharge to a health care facility (OR, 2.66; 95% CI, 1.07-6.63; P = .035), discharge on an anticoagulant (OR, 2.31; 95% CI, 1.13-4.72; P = .021), white race (OR, 2.3; 95% CI, 1.21-4.34; P = .011), and female sex (OR, 2.02; 95% CI, 1.06-3.85; P = .033). Kaplan-Meier analysis showed that freedom from graft site infection at 1 year was 96.4%. Longer term graft infection at 1 year was independently associated with IV drug use history (hazard ratio [HR], 1.98; 95% CI, 1.06-3.68; P = .032), initial discharge to a health care facility (HR, 1.88; 95% CI, 1.19-2.97; P = .007), and white race (HR, 1.64; 95% CI, 1.23-2.19; P = .001). ConclusionsAlthough significant AVG infection was uncommon in the Vascular Quality Initiative, the majority were treated with graft removal. In select high-risk patients, extra care should be taken and alternative forms of arteriovenous access may be considered.

Complete versus partial excision of infected arteriovenous grafts: Does remnant graft material impact outcomes?

ObjectiveInfected arteriovenous grafts necessitate intervention to obtain source control. However, excising the graft material can be challenging and can lead to complications. Leaving a cuff of graft at the sites of anastomosis allows for the avoidance of potential risks. However, it is unclear whether doing so places patients at risk of recurrent graft infection. The purpose of the present study was to investigate the effect of complete vs partial excision of infected arteriovenous prosthetic dialysis access grafts. MethodsThe data from all patients who had undergone surgical intervention for infected arteriovenous grafts at a single institution were retrospectively reviewed. The patients were grouped according to intervention type: complete excision and partial excision of arteriovenous prosthetic grafts. Partial excisions were further substratified based on whether flow had been restored through the arteriovenous access. The primary outcome was freedom from subsequent intervention for infection, defined as the number of days from excision to subsequent reoperation for reinfection. Freedom from infection was analyzed using the Kaplan-Meier method. ResultsA total of 117 patients had undergone surgical intervention for 122 infected arteriovenous grafts from 2003 to 2016. Of these 117 patients, 79 (64.8%) had undergone partial excision of infected arteriovenous grafts, and 43 (35.2%) had undergone complete excision with vascular repair. Within the partial excision cohort, 71 infected arteriovenous grafts (58.2%) were not flow restored and 8 (6.6%) were flow restored using either prosthetic or autogenous interpositions. The median follow-up time was 2.4 years (interquartile range, 0.6-4.5 years). The most common causative organisms included methicillin-resistant Staphylococcus aureus (n = 34; 27.9%), methicillin-sensitive S. aureus (n = 17; 13.9%), and S. epidermidis (n = 15; 12.3%). The recurrent infection rate in the partial excision group was 16.5% (n = 13) compared with 2.3% (n = 1) in the complete excision group. In the flow-restored subcohorts, those with restoration using prosthetic interposition grafts had the greatest reinfection rate at 57.1% (n = 4), and those with restoration using autogenous conduits did not experience reinfection (P = .033). ConclusionsIncomplete excision of infected arteriovenous prosthetic grafts was associated with a higher rate of reinfection compared with complete graft excision. Complete excision presents technical challenges but could provide superior source control in managing infected dialysis access. Complete excision with vascular reconstruction should be performed when possible to avoid leaving remnant prosthetic material.

18F-FDG PET/CT and 99mTc-HMPAO-WBC SPECT/CT effectively contribute to early diagnosis of infection of arteriovenous graft for hemodialysis.

An arteriovenous graft (AVG) is indicated in hemodialysis patients with failed arteriovenous access. Early treatment of AVG infection is important because an advanced prosthetic infection leads to the removal of the prosthesis. The aim of this study was to evaluate the benefits of 18F-FDG PET/CT and 99mTc-HMPAO-WBC SPECT/CT in early detection of AVG infections. Fifty-one AVGs were evaluated. 18F-FDG PET/CT and 99mTc-HMPAO-WBC SPECT/CT studies were performed at intervals of 10, 20-30, and 40-50 weeks after AVG insertion. Agreement between the imaging methods and reference parameters (i.e. clinical presentation, C-reactive protein and microbiological findings on the hemodialysis cannula extracted after hemodialysis from AVG) was evaluated. The study results showed that focal accumulation of the radiopharmaceuticals can be considered a sign of AVG infection. At 10 weeks after AVG implantation, the focal 18F-FDG findings showed the best agreement with the reference parameters (agreement coefficients AC1 - clinical status: 0.693, CRP: 0.605, cannula microbiology: 0.518, respectively). At 20 to 30 weeks after AVG implantation, the diagnostic value of focal 99mTc-HMPAO-WBC accumulation increased (AC1 coefficients: 0.658, 0.658, 0.408) and was similar to that of focal 18F-FDG uptake (AC1s: 0.656, 0.570, 0.409). Between 40 and 50 weeks since AVG implantation, the diagnostic significance of focal 99mTc-HMPAO-WBC accumulation (AC1 coefficients: 0.771, 0.811, 0.611) slightly exceeded the diagnostic value of focal 18F-FDG accumulation (AC1 coefficients: 0.524, 0.456, 0.569). 18F-FDG PET/CT and 99mTc-HMPAO-WBC SPECT/CT can both serve as important tools contributing to early diagnosis of AVG infection.

Vascular Access for Hemodialysis Patients: New Data Should Guide Decision Making.

This commentary critically examines key assumptions and recommendations in the 2006 Kidney Disease Outcomes Quality Initiative vascular access guidelines, and argues that several are not relevant to the contemporary United States hemodialysis population. First, the guidelines prefer arteriovenous fistulas (AVFs) over arteriovenous grafts (AVGs), on the basis of their superior secondary survival and lower frequency of interventions and infections. However, intent-to-treat analyses that incorporate the higher primary failure of AVFs, demonstrate equivalent secondary survival of both access types. Moreover, the lower rate of AVF versus AVG infections is counterbalanced by the higher rate of catheter-related bloodstream infections before AVF maturation. In addition, AVFs with assisted maturation (interventions before successful AVF use), which account for about 50% of new AVFs, are associated with inferior secondary patency compared with AVGs without intervention before successful use. Second, the guidelines posit lower access management costs for AVFs than AVGs. However, in patients who undergo AVF or AVG placement after starting dialysis with a central venous catheter (CVC), the overall cost of access management is actually higher in patients receiving an AVF. Third, the guidelines prefer forearm over upper arm AVFs. However, published data demonstrate superior maturation of upper arm versus forearm AVFs, likely explaining the progressive increase in upper arm AVFs in the United States. Fourth, AVFs are thought to fail primarily because of aggressive juxta-anastomotic stenosis. However, recent evidence suggests that many AVFs mature despite neointimal hyperplasia, and that suboptimal arterial vasodilation may be an equally important contributor to AVF nonmaturation. Finally, CVC use is believed to result in excess mortality in patients on hemodialysis. However, recent data suggest that CVC use is simply a surrogate marker of sicker patients who are more likely to die, rather than being a mediator of mortality.

The forearm arteriovenous graft between the brachial artery and the brachial vein as a reliable dialysis vascular access for patients with inadequate superficial veins

ObjectiveThe arteriovenous fistula (AVF) is recommended as the preferred hemodialysis access. However, placing an AVF in all patients may result in poor access outcomes and increased central venous catheter (CVC) use because of increased comorbid conditions, age, and suboptimal vessels. In patients with inadequate superficial veins for AVFs, the use of the brachial veins for creation of forearm arteriovenous grafts (AVGs) has received limited attention. This retrospective study aimed to evaluate outcomes of forearm brachial-brachial AVGs (BB-AVGs) placed in patients with poor superficial veins. MethodsWe identified 111 BB-AVGs created in 111 consecutive patients, using standard-walled polytetrafluoroethylene grafts, between January 2010 and December 2015. After excluding 6 patients (non-dialysis initiation, missing information, and death within 1 month), we included 105 patients from 21 dialysis centers. We analyzed primary failures, time to cannulation, patency, complications, and revisions. Patency rates were calculated by the Kaplan-Meier method. The incidence of complications and revisions was expressed as number of events per person-year. ResultsA total of 105 patients (median age, 69 years) were followed up for a median time of 21.2 months (interquartile range, 9.2-36.5 months). Of the patients, 72.4% were on chronic hemodialysis and had previously undergone one or more access procedures. At the time of BB-AVG placement, prior accesses were 39 AVFs, 20 tunneled CVCs, and 17 AVGs. BB-AVG rates of primary failure and revision before cannulation were 7.6% and 5.7%, respectively. BB-AVGs were cannulated after a median time of 3.4 weeks (interquartile range, 2.8-4.1 weeks). Primary patency rates at 12, 24, and 36 months were 49.5%, 29.5%, and 19.5%. Secondary patency rates at 12, 24, and 36 months were 76.3%, 62.7%, and 54.6%. After cannulation, the incidence of complications and revisions was 1.054 and 0.649 per person-year, respectively. Most complications and interventions were due to thrombosis (0.527 per person-year) or stenosis (0.381 per person-year) and related interventions (0.490 per person-year). A minority of patients experienced AVG infections (0.052 per person-year), with only two requiring access removal. ConclusionsIn patients with poor superficial veins, the forearm BB-AVG is a reliable access because of low access-related morbidity and considerable long-term access survival. BB-AVG placement has the advantage of preserving proximal vessels. In these patients, such an approach can delay both rapid exhaustion of vascular sites and early recourse to CVC permanent use.

Current Concepts in Hemodialysis Vascular Access Infections.

Infection-related causes are second only to cardiovascular events for mortality among end-stage renal disease patients. This review will provide an overview of hemodialysis catheter-, graft-, and fistula-related infections with emphasis on diagnosis and management in specific settings. Use of catheters at the initiation of dialysis has remained unchanged at 80%. Of all access-related bloodstream infections (BSIs), 70% occur in patients with catheters. The risk factors for BSIs in tunneled, cuffed catheters include the duration of the catheter, past catheter-related bacteremia, left-sided internal jugular vein catheters, hypoalbuminemia, and immunosuppression. Surprisingly, human immunodeficiency virus infection has not been associated with a higher risk of catheter-related bacteremia. Catheter-related bloodstream infection is a clinical definition that requires specific laboratory testing to identify the catheter as the source of the BSI. A central line-associated bloodstream infection is a primary BSI in a patient who had a catheter within the 48-h period before the development of the BSI with no other identifiable source. Guidewire exchange of catheter is a viable alternative in select patients to aid in preserving venous access sites. Catheter lock therapy can decrease infectious complications and mortality. Arteriovenous graft infections are prevalent with significant morbidity. Studies evaluating the impact of stent use in infection risks of the arteriovenous graft are sorely needed.