GUIDELINES [ back to index ]
8. Post operative control of A/V fistula and graft function (1)
*1 Surgeon
• Immediate postoperative evaluation comprises palpation of peripheral pulses and arterio-venous thrill. Auscultation may fail to detect arterio-venous murmur in tiny vessels – a frequent phenomenon in children. Doppler examination is then necessary to exclude early failure. The absence of murmur in adults in most cases indicates early failure. Haematoma or haemorrhage have to be excluded as well as peripheral ischaemia and neurological impairment, which may indicate steal syndrome. Development of acute ischaemic monomelic neuropathy, especially after creation of an elbow fistula in a diabetic patient, needs to be recognised.
• Wound healing should be complete after the first week. Therefore, a surgical examination within 10 days is useful to exclude skin necrosis, infection, and to remove sutures, if necessary, and assess fistula patency. At this time, a thrill should be palpable, and a murmur heard during auscultation. Again thorough assessment of the peripheral circulation and sensorimotor function of the hand is necessary, if the patient complains of symptoms of steal syndrome.
*2 Patient education
• The well informed, well prepared patient is the best partner. Patients should be trained to monitor the function of their vascular access daily. This self-assessment training can be performed by a nurse or a technician in one training session, supplemented by brochures and videos. The use of a diary may be helpful to ensure patient compliance.
• Patients should be taught to feel the pulse and thrill in their A/V fistula or graft. Simple palpation can reveal differences in intravascular pressure, indicating early development of aneurysm and stenosis. If possible, the patient should be instructed to use a stethoscope for auscultation of the vascular access. They should look for redness, swelling, new or changing pseudoaneurysms or evidence of pustule formation and report any development of pain. Abnormalities or changes should be brought to the attention of the patients’ care team.
*3 Treatment of access site
• Patients should be taught how to wash the skin with soap and water daily and before dialysis.
• They should be advised to check that the cannulation site is rotated, except for the use of the buttonhole technique, see algorithm “Routine management of A/V fistula and graft” *17.
*4 Use of access arm
• Patients should be advised to avoid high pressure on their access site caused by occlusive clothes, by sleeping on the access arm or during compression of the bleeding access at the end of dialysis1.
• They must avoid carrying heavy items with the access arm 1.
*5 Nephrologist and staff
• Clinical signs such as pain, redness, swelling, haematoma, intravascular pressure etc. can be obtained routinely by history, inspection, palpation and auscultation.
• Routine computer-assisted documentation of all access-relevant data should be available in the future and include reports of all surgical and interventional procedures, results of ultrasonographic and radiological diagnostic investigations and the routinely documented data, such as arterial and venous pressure, during dialysis therapy. Trends should be monitored automatically.
*6 Management of anastomotic infection
• In forearm A/V fistulas and grafts, wound infection always means anastomotic infection with the risk of erosion and bleeding. Patients with signs and symptoms of infection following access creation should be immediately hospitalised and consequently treated.
*7 A/V Fistula: surgical intervention
• In A/V fistulas, uncomplicated infection without false aneurysm or bleeding (confirmed by colour-coded duplex-ultrasound) can be treated with antibiotics alone. In case of systemic signs of infection, excessive discharge of pus or progressive skin necrosis, early surgical wound revision is indicated.
• False aneurysms or active bleeding urge immediate surgical exploration of the anastomosis. The surgeon has to decide whether suturing the infective dehiscence of the anastomosis is possible or whether resection of the anastomosis with reconstruction of the artery is necessary 2.
*8 Graft: surgical intervention
• Following graft implantation, wound infection means infection of the complete graft and of both anastomoses. Antibiotic treatment alone is not likely to eliminate the infective agent. Hence a complete removal of the foreign body is advisable before local or systemic complications occur. The artery can be reconstructed by vein patching at the anastomotic site, the vein may be ligated proximally and distally to the anastomosis unless it is the main draining vein of the respective extremity 3. A more conservative approach by leaving small cuffs of the graft on the artery and vein as patches, has also been performed successfully in those cases where the infection does not involve the anastomosis 3 4 5 6.