Campylobacter fetus Bacteremia Related to Vascular Prosthesis and Pseudoaneurysm Infection: A Case Report and Review.

BACKGROUND: Campylobacter fetus rarely causes gastrointestinal diseases but shows an affinity for the endovascular epithelium. METHODS: We describe a case of C. fetus bacteremia related to vascular prosthesis and pseudoaneurysm infection, with a review of the literature. RESULTS: A 67-year-old male was admitted with a history of fever, weakness and painful swelling of the groin. After unsuccessful treatment with ciprofloxacin, the patient was transferred to our hospital, where he had been previously treated for aortoiliac occlusive disease including a prosthetic aortobifemoral and popliteal bypass with polyester graft placement. An angiography showed a pseudoaneurysm in the groin and, therefore, repair of the pseudoaneurysm, removal of the prosthesis and biologic graft placement were performed. Blood cultures and tissue samples of the vascular prosthesis and pseudoaneurysm yielded C. fetus resistant to ciprofloxacin. The patient was treated with meropenem for four weeks, followed by amoxicillin-clavulanate for another two weeks after discharge. Eight previously published cases of C. fetus bacteremia due to infected cardiovascular prosthetic devices (prosthetic heart valves, implantable cardioverter-defibrillators and a permanent pacemaker) were summarized in the review. CONCLUSIONS: To our knowledge, this is the first report of a C. fetus bacteremia related to post-surgical infection of a vascular prosthesis causing a pseudoaneurysm.

The Femoral Venoarterial Perfusion During Open Abdominal Aortic Aneurysm Repair in Patient With Renal Transplant.

We report of a patient with abdominal aortic aneurysm and renal transplant who underwent aneurysm repair. These patients can be treated by eather open or endovascular approach, depending on several factors, including aneurysm morphologic suitability for endovascular tretament, age of patient, and comorbidities.The main challange with open repair approach is to maintain renal transplant perfusion during the aortic cross clamping. Several methods of renal transplant perfusion during aneurysm repair have been described. In this case, we opted for open aneurysm repair beacuse of the age of the patient. The femoral venoarterial perfusion technique using extracorporal circulation machine was employed. We found this technique safe and easy in treating such patients.

Role of Doppler ultrasonography in the evaluation of hemodialysis arteriovenous access maturation and influencing factors.

The goal of vascular access creation is to achieve a functioning arteriovenous fistula (AVF) or arteriovenous graft (AVG). An autologous fistula has been shown to be superior to AVG or to central venous catheters (CVCs) with lowest rate of re-intervention, but vessel obstruction or immaturity accounts for 20 % to 54% of cases with primary failure of AVF. This review is focused on the factors influencing maturation; indication and timing of preoperative mapping/creation of vascular access; ultrasound parameters for creation AVF/AVG; early postoperative complications following creation of a vascular access; ultrasound determinants of fistula maturation and endovascular intervention in vascular access with maturation failure. However, vascular accesses that fail to develop, have a high incidence of correctable abnormalities, and these need to be promptly recognized by ultrasonography and managed effectively if a high success rate is to be expected. We review approaches to promoting fistula maturation and duplex ultrasonography (DUS) of evaluating vascular access maturation.

Quality indicators of vascular access procedures for hemodialysis.

Improved quality of surgical procedures can minimize complications, the morbidity and mortality of patients, and in addition decrease costs. Quality indicators in angioaccess surgery are, however, not clearly defined. The aim of this review article is therefore to find the most important factors affecting quality in vascular access procedures. Even though autogenous arteriovenous fistula has been recognized as the best vascular access for hemodialysis, the high percentage of unsuccessful attempts associated with it raises the question about quality assessment in angioaccess procedures. Unfortunately, quality indicators in vascular access surgery are difficult to define and measure. Among those that can be obtained are: the time between the presentation of patients to a vascular access surgeon and the construction of a fistula, the percentage of autogenous fistulas, the percentage of functional fistulas in prevalent and incident hemodialysis patients, the percentage of creation of a functional fistula in the first attempt, and durability of an access. Organizational improvement and educational programs are also necessary at institutions with inferior quality indicators of vascular access care, as even small increase in quality may mean the survival of an individual patient. Quality indicators in angioaccess surgery can also serve as a helpful tool in choosing the best vascular access surgeon or vascular access center. The choice can consequently reflect on increased survival and quality of life in patients needing hemodialysis.

The Advantages of Using Vascular Dilators in Angioaccess Surgery.

The creation of a functional angioaccess is the cornerstone in treatment of chronic hemodialysis patients. The aim of this article is to review the use of vascular probes as a simple and cheap tool that could help surgeons in preparation of vessels and with creation of an anastomosis. Autogenous arteriovenous fistula is the best angioaccess available but is hampered by its relatively high non-maturation rate. Guidelines recommend preoperative duplex ultrasonography (USG) and use of vessels with a diameter that is able to maintain sufficient flow and fistula maturation to avoid unsuccessful attempts. Despite recommendations, preoperative duplex USG is not performed in many centers. In such circumstances, the use of vascular probes could help surgeons to create a fistula with a high chance of successful maturation. Vessel probes and dilators could be used to assess vessel diameter and patency, the ability to dilate and resolve a spasm, to stop retrograde blood flow in the vein (to avoid the use of vascular clamps), to avoid torsion of vein, to open and check vessel lumen with each stitch (to avoid using the forceps and possible wall injury), for tightening of continuous suture over the probe (to avoid excessive tightening and possible anastomotic stenosis). To my knowledge, this is the first review article which summaries the experience of using vascular dilators in angioaccess surgery. This information can be very helpful especially when there is the lack of valid preoperative USG of the vessels.

Quality assessment of vascular access procedures for hemodialysis: A position paper of the Vascular Access Society based on the analysis of existing guidelines.

Quality assessment in vascular access procedures for hemodialysis is not clearly defined. The aim of this article is to compare various guidelines regarding recommendation on quality control in angioaccess surgery. The overall population of end-stage renal disease patients and patients in need for hemodialysis treatment is growing every year. Chronic intermittent hemodialysis is still the main therapy. The formation of a functional angioaccess is the cornerstone in the management of those patients. Native (autologous) arteriovenous fistula is the best vascular access available. A relatively high percentage of primary failure and fistula abandonment increases the need for quality control in this field of surgery. There are very few recommendations of quality assessment on creation of a vascular access for hemodialysis in the searched guidelines. Some guidelines recommend the proportion of native arteriovenous fistula in incident and prevalent patients as well as the maximum tolerable percentage of central venous catheters and complications. According to some guidelines, surgeon's experience and expertise have a considerable influence on outcomes. There are no specific recommendations regarding surgeon's specialty, grade, level of skills, and experience. In conclusion, there is a weak recommendation in the guidelines on quality control in vascular access surgery. Quality assessment criteria should be defined in this field of surgery. According to these criteria, patients and nephrologists could choose the best vascular access center or surgeon. Centers with best results should be referral centers, and centers with poorer results should implement quality improvement programs.

The importance of success prediction in angioaccess surgery.

Access to the circulation is an "Achilles' heel" of chronic hemodialysis. According to the current guidelines, autologous arteriovenous fistula is the best choice available. However, the impossibility of immediate use and the high rate of non-matured fistulas place fistula far from an ideal hemodialysis vascular access. The first attempt at constructing an angioaccess should result in functional access as much as possible. After failed attempts, patients and nephrologists lose their patience and confidence, which results in high percentage of central venous catheter use. Predictive models could help, but clinical judgment still remains crucial. Early referral to the nephrologist and vascular access surgeon, careful preoperative examinations, preparation of patients and duplex sonography mapping of the vessels are very important in the preoperative stage. In the operative stage, it is crucial to understand that angioaccess procedures should not be considered as minor procedures and these operations must be performed by surgeons with demonstrable interest and experience. In the postoperative stage, appropriate surveillance of the maturation process is also important, as well as good cannulation skills of the dialysis staff. The purpose of this review article is to stress the importance of success prediction in order to avoid unsuccessful attempts in angioaccess surgery.

Arteriovenous fistula for haemodialysis: The role of surgical experience and vascular access education / Fístula arteriovenosa para hemodiálisis: el papel de la experiencia quirúrgica y la educación sobre el acceso vascular

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Vein diameter after intraoperative dilatation with vessel probes as a predictor of success of hemodialysis arteriovenous fistulas.

BACKGROUND: Vascular access is "the life line" for patients on chronic hemodialysis. The autogenous arteriovenous fistula provides the best access to the circulation because of low complication rate, long-term use, and lower cost, compared to arteriovenous graft and central venous catheter. The primary objective of this prospective study was to investigate the predictive value of vein diameter after intraoperative dilatation with vessel probes on hemodialysis fistula maturation. MATERIAL AND METHODS: Ninety-three fistulas were performed by a single surgeon from February 1, 2006 to January 31, 2009. Intraoperative vein dilatation with vessel probes was attempted in all fistulas. Measurements of the feeding artery diameter, vein diameter and the increased vein diameter after intraoperative dilatation were performed and immediate failure, early patency, early failure, primary patency, and fistula survival outcomes were recorded during 48-month follow-up. RESULTS: Early failure occurred in 20% of fistulas and 70% matured sufficiently for cannulation. Variables with significant impact on the failure to mature by univariate analysis were: body-mass index (P=0.041), artery diameter (P<0.001), vein diameter (P=0.004), and vein diameter after dilatation (P=0.002). However, but multivariate analysis showed that only body-mass index (P=0.038), artery diameter (P=0.001), and the diameter of the vein after dilatation (P=0.018) significantly affected maturation. In a group of 56 (60%) patients with vein diameter before dilatation ≤ 2 mm, among vessel characteristics found by multivariate analysis, only vein diameter after dilatation (P=0.004) significantly affected function. CONCLUSIONS: Artery diameter and vein diameter after intraoperative dilatation with vessel probes were the main predictors of fistula function.