Duplex ultrasound scanning in the assessment of arteriovenous fistulas. Objective to measure the accuracy of transrectal ultrasound in detecting fistulous tracts and internal openings in preoperative evaluation of fistulainano. The vein will also frequently show a poor response to. Us fistula evaluation results were analyzed retrospectively in 69 patients within 4 months after avf placement. A probe or transducer is used to obtain us image on the. Native arteriovenous fistula avf is the vascular access of choice for hemodialysis patients. Role of duplex ultrasound in fistula planning and diagnostics.
The protocol for vascular mapping before hemodialysis access placement has been previously described. A vein is a blood vessel that carries blood back toward your heart. Patients with severe renal insufficiency and endstage renal disease require renal replacement therapy i. A detailed protocol for the performance and interpretation of duplex ultrasound evaluation of hemodialysis access is described. Measurements of the vein diameter were recorded from the ultrasound scan images at eight representative sites. One hundred twentysix new renal transplants were scanned regularly with color doppler ultrasound cdu. Ultrasound evaluation of dialysis access grafts and fistulas. An arteriovenous fistula is an abnormal connection or passageway between an artery and a vein. The arteriovenous fistula avf has long been recognized as the preferred access. Doppler ultrasound of av access for hemodialysis slideshare. Connecting the vein and artery is a surgical procedure. Standardized protocol for hemodialysis vascular access.
Dysfunction of the av access is a significant problem, especially in prosthetic grafts, and is a frequent. The recipient vein may be dilated and show an arterialized flow pattern. Eighty percent of the patients with endstage renal disease in denmark receive hemodialysis, the predominant form of renal replacement therapy. Vascular ultrasound for the preoperative evaluation prior. A preoperative vein mapping allows the surgeon to choose the configuration of av fistula that provides the highest likelihood of maturation. The operation to create the av fistula is usually carried out around 4 to 8 weeks before haemodialysis begins.
In chronic renal failure patients under longterm hemodialysis, native and graft arteriovenous fistulas avfs are more favored than a hemodialysis catheter because of their lower morbidity and better prognosis. Sutures to be removed 710 days post av fistula formation. Evaluation of traumatic groin arteriovenous fistulas with duplex doppler sonography. It may be congenital, surgically created for hemodialysis treatments, or acquired due to pathologic process, such as trauma or erosion of an arterial aneurysm. The most common mode of failure of a native av fistula is outflow vein stenosis, followed by anastomotic stenosis 3. This allows the tissue and skin surrounding the fistula to heal. Arteriovenous fistula procedure, blood, tube, removal. Color doppler ultrasound and arteriovenous fistulas for hemodialysis. Wiener cardiovascular institute, mount sinai medical center, new york, ny 10029, usa.
Vascular laboratory protocol and ultrasound mapping. The direct sign is visualization of the fistulous communication seen as a disturbed highvelocity jet of blood on color doppler imaging. Doppler ultrasound dus, arteriovenous fistula avf, preoperative vascular. Color flow and imagedirected doppler ultrasound evaluation of iatrogenic arteriovenous fistulas in the groin. Data were acquired using the above protocol by 3 ultrasound users 1 sonologist and 2 sonographers, both with registered diagnostic medical sonographer credentials and 1 also with registered vascular technologist credentials with an average of 15 years of experience range, 922 years in an american college of radiologyaccredited laboratory. Ultrasound guided non surgical closure of post angiographic. Management options include surgical thrombectomy versus thrombolysis with streptokinase or tissue plasminogen activator with or without angioplasty. Compared with grafts and central venous catheters, avfs last longer and are. When the link is made, the arterys higher pressure pushes blood into the vein. The basic principles are easily learned and are similar to those for examining an av fistula.
In europe, doppler ultrasound has become the standard of care for evaluation of arteriovenous av fistula dysfunction and is essential in the preoperative evaluation for access placement. Ultrasound offers the advantage of dynamic imaging without the risks of radiation exposure and can be done as an office based procedure using portable equipment. This scan is performed to determine if there is a problem with a dialysis fistula or graft. In order to standardize native and prosthetic arteriovenous fistula avf.
When the surgeon connects an artery to a vein, the vein. Source of data this study was conducted in the department of surgery, st. The groundbreaking article by brescia and cimino in 1966 revolutionized the creation of the vascular. Handbook on ultrasound for vascular access examination from the specialist to the nurse medical ultrasound us is based on the use of highfrequency sound and the analysis of the variation that exists when it rebounds off different structures. Role of transrectal ultrasound scan in patients with.
Ultrasound to predict stealsyndrome after arteriovenous. A surgeon connects an artery to a vein, usually in your arm, to create an av fistula. The printing of this book has been sponsored by an unrestricted. An acquired arm arteriovenous fistula avf creation is a procedure performed for haemodialysis access in those with end stage renal failure. Finding the time to use the ultrasound prior to and during cannulation availability and costs of portable ultrasound machines the types of patientaccesses most likely to benefit from the use of ultrasound are likely to include. When a hemodialysis arteriovenous fistula havf is created, it is important to wait for venous dilatation and volume flow increase through the havf, a phenomenon called maturation. Studies in emergency departments and particularly in paediatric care have suggested that us guidance can improve the speed and accuracy of cannulation in peripheral veins for. Aium practice parameter for the performance of vascular. Unlike an arteriovenous malformation avm, these are frequently acquired lesions, rather than developmental abnormalities.
The ultrasound evaluation of the pseudoaneurysm allows to identify the size of the pseudoaneurysm and of the communicating channel. Arteriovenous fistulas have a number of etiologies. However, after the creation of an avf, problems, including immediate thrombosis, failing to mature, or even early fistula failure, might develop 2, 3. Av fistula the best type of longterm access is an av fistula. Haemodialysis arteriovenous fistula radiology reference. Ultrasound examinations for postoperative assessment of hemodialysis. This is a prospective study where the research team will acquire data from the patients after they have signed the informed consent form. An arteriovenous fistula avf is an abnormal connection between an adjacent artery and vein. A duplex ultrasound study confirmed an arteriovenous fistula avf at the level of the proximal posterior tibial artery pta or distal popliteal artery. Nevertheless, it is a good technique for detecting significant clinical problems and should. As with the veins in the calf, the veins of the forearm genarally run in pairs venous commantantes. Guidelines on the management of arterio venous fistula and grafts.
The goal of duplex ultrasound testing is to provide the dialysis access surgeons with anatomic and physiologic information to construct a highflow dialysis access and maximize the number of primary autogenous fistula performed. Arteriovenous fistula and graft evaluation in hemodialysis. Preoperative, intraoperative, postoperative, 510 days, 46 weeks, 6 months, and 1 year. Performance of vascular ultrasound examinations for postoperative assessment of hemodialysis access introduction t he american institute of ultrasound in medicine aium is a multidisciplinary association dedicated to advancing the safe and effective use of ultrasound in medicine through professional and public education, research, development. Ultrasound with color doppler is a sensitive modality for diagnosing uterine vascular malformations especially av fistulae. Av fistula thrombosis is quickly identified by examining the fistula site for the absence of a bruit and thrill. This is a brief introduction to the use of color doppler imaging using the carotid artery as an example. To evaluate the time required for havf maturation using ultrasound criteria. To compare various objective ultrasonographic us criteria for native arteriovenous fistula avf maturation with subsequent fistula outcomes and clinical evaluation by experienced dialysis nurses. Home books arteriovenous fistulas diagnosis and management. After a few months, the vein will become larger and its walls will become. For radiocephalic avf, a metaanalysis estimated modest primary 63% and secondary 66% patencies at 1 year 2. Volume flow in arteriovenous fistulas using vector. Allow avg 36 weeks after placement before cannulation, this will allow swelling to subside.
Color doppler ultrasound and arteriovenous fistulas for. Cannulation tips for a dialysis technician dialysis. However, avf failure has become more common over the last three decades as more patients are older, and have diabetes or vascular disease. Protocol for creation of an av fistula andor synthetic graft 1. Duplex ultrasound is a useful tool in the planning, creation, diagnostics, and troubleshooting of avfs. An arteriovenous fistula av fistula is the connection of a vein and an artery, usually in the forearm, to allow access to the vascular system for hemodialysis, a procedure that performs the functions of the kidneys in people whose kidneys have failed. Doppler us of av access for hemodialysissamir haffar m. Download citation hemodialysis access ultrasound maintenance of hemodialysis graft and fistula patency is becoming even more important as the number of patients with endstage renal disease. The vascular access planning guide for professionals is the companion document to the patient guide, planning for your vascular access, and it is important to use both together. Duplex ultrasound evaluation of hemodialysis access. Arteriovenous fistula, blood access, central vein catheters, surgical salvage introduction in 1966, brescia and colleagues described the creation of an arteriovenous fistula avf using the radial artery and an adjacent vein 1.
Ultrasound evaluation before and after hemodialysis access. Protocols in the usa require a flow volume of at least 350 mlmin, while smaller. Protocol and technique of dialysis ultrasound surveillance. Allow the arteriovenous fistula to mature for 34 months after formation and before cannulation. The echocolor doppler technique is useful for identifying the pseudoaneurysms and the arteriovenous fistulas. The arteriovenous fistula avf is the preferred access for haemodialysis 1. A fistula is usually situated in the patients upper or lower arm. Use of portable ultrasound to support cannulation of av. An endovascular intervention resulted in successful coverage of the avf and improvement of distal limb perfusion figure 1. Outflow vein stenosis can occur at a sclerotic, scarred or iatrogenically constricted area.
Aneurysm development and degenerative changes in dilated artery proximal to arteriovenous fistula. Ultrasound guided cannulation of dialysis fistulas full. Gray scale ultrasound features may be nonspecific, demonstrating a hypoechoic mass or multiple anechoic channels within the uterine myometrium. Still with the patient seated on the side of the bed, follow the radial and ulnar veins to the wrist confirming compressibility and flow. The preferred access for longterm hemodialysis is the surgically.
Last editions of the clinical guidelines on vascular access. Grayscale transverse plane imaging is used to identify vessels artery and vein and evaluate their diameter and wall thickness. To study the role of transrectal ultrasound scan in patients with fistulainano. This can either be a native connection or a connection using a ptfe polytetrafluoroethylene graft. An artery is a blood vessel that carries blood away from your heart. The patient guide is designed to meet the information needs of patients and to reinforce the central role they play in the access planning process. The arterialvenous av fistula the av fistula uses the patients native vein and artery to make a connection. Ultrasound technology is safe and images arteries and veins. Acquired arteriovenous fistula of the lower extremity. There is still some controversy as to the exact time required for this maturation to occur. Data will be collected before, during and after the arteriovenous fistulaavfplacement, and during followup at predefined time intervals. Normal ultrasound doppler parameters for functioning av fistulas. Access is the lifeline for the hemodialysis patient, but its creation and maintenance is a difficult.