Diese Präsentation wurde erfolgreich gemeldet.
Wir verwenden Ihre LinkedIn Profilangaben und Informationen zu Ihren Aktivitäten, um Anzeigen zu personalisieren und Ihnen relevantere Inhalte anzuzeigen. Sie können Ihre Anzeigeneinstellungen jederzeit ändern.

A v fistula in heamodialysis

32.687 Aufrufe

Veröffentlicht am

Veröffentlicht in: Gesundheit & Medizin

A v fistula in heamodialysis

  1. 1. A-V Fistula in HeamodialysisTechniques and ComplicationsDr- Saeed Al-ShomimiKing Faisal University Saudi Arabia2003<br />
  2. 2. Introduction<br />Definition<br />Abnormal connection between artery and vein which bypasses capillary bed<br />Aetiology<br /> congenital <br /> acquired:- surgically created for haemodialysis- penetrating trauma- iatrogenic eg following surgical dissection of artery, cannulation of artery or vein<br />
  3. 3. Introduction<br />The advent of hemodialysis in the early 1960 has provided longevity for many patients with CRF<br />Quinton and his associates -> external A-V shunt<br />1963 , Shaldon -> femoral vien catheter<br />
  4. 4. Introduction<br />Fistula vs Graft<br /><ul><li>Maturation</li></ul>Fistula 4 -8 weeks<br />Graft 2- 4 weeks<br /><ul><li>Infection
  5. 5. Blockage (thrombosis)
  6. 6. Other complications:</li></ul>Psudoaneurysm<br />Venous hypertension<br /><ul><li>Cosmotic</li></li></ul><li>Introduction<br /> Grafts:<br /><ul><li>Vein
  7. 7. Artificial:</li></ul>Gortex<br />Teflon<br /><ul><li>Straight
  8. 8. looped</li></li></ul><li>
  9. 9. Anatomy<br />
  10. 10. Anatomy<br />
  12. 12. General Principles<br />Preferable to use the arm vessels rather than the leg vessels<br /> When possible the non-dominant arm<br />Access site should be placed as distally as practical in the limb , so that proximal sites will be available for subsequent procedures.<br />3. Inadequate or atherosclerotic arteries should be avoided , and a long section of patent vein is required to accommodate multiple cannulation site.<br />
  13. 13. General Principles<br />The chosen site should allow for ease of access for cannulation and should be positioned so that patient comfort is assured during heamodialysis.<br />Technical precision and gentle tissue handling is mandatory.<br />A temporary access procedure , such as :<br /><ul><li>Rt Internal jagular
  14. 14. Subclavian or femoral catheter
  15. 15. External shunt
  16. 16. Peritoneal catheter</li></ul> required during the time that the permanent access are maturing prior to use.<br />
  17. 17. General Principles<br />Anticoagulation is not necessary during routine access operations , except for graft thrombectomy and revision procedures, or patients who do not have the usual hypocoagulable state of chronic renal failure.<br />8. Prophylactic antibiotics are used for all cases involving insertion of prosthetic material.<br />
  18. 18. Preservation of access vessels<br />The autogenenous AV fistula at the wrist is the procedure of choice <br />Most second choice procedures also make use of the forearm , with the principle access vessels being the :<br /><ul><li>Radial – brachial artery
  19. 19. Cephalic and cubital fossa veins</li></ul>So these vessels should be preserved by avoidance of:<br /><ul><li>Venipuncture
  20. 20. Intravenous cannulation
  21. 21. Invasive monitoring lines</li></li></ul><li>Procedure choices in vascular access surgery<br />First choice:<br /><ul><li>Radiocephalic direct AV fistula</li></ul>Brescia-Cimino (wrist)<br />Snuff-box (base of the thumb)<br />Second choice:<br /><ul><li>Forearm AV graft bridge fistula</li></ul>Straight : radial artery -> largest superficial vein of the cubital fossa<br />Loop : brachial artery -> largest superficial vein of the cubital fossa<br /><ul><li>Brachioaxillary graft
  22. 22. Upper arm AV fistula (brachial basilic)</li></li></ul><li>Procedure choices<br />Third choice:<br /><ul><li>Forearm AV graft to brachial vein</li></ul>Straight : radiobrachial<br />Loop : brachiobrachial<br />Forth choice:<br /><ul><li>Femorosaphenous graft
  23. 23. Femorofemoral graft</li></ul>Others:<br /><ul><li>Axilloaxillary graft
  24. 24. Illiac-femoral graft
  25. 25. miscellaneous </li></li></ul><li>Surgical Techniques<br />
  26. 26. Surgical Techniques<br />Four different anastomotic connections of artery and vein are in common use and each has its advantages and disadvantages<br />Side to side anastomosis:<br /><ul><li>Technically is the easiest anastomosis
  27. 27. Highest fistula flow</li></ul>End to side (artery to vein):<br /><ul><li>Minimize turbulence and distal steal
  28. 28. Slightly lower fistula flow
  29. 29. Twisting of the artery during construction</li></li></ul><li>Surgical Techniques<br />3. End to side (vein to artery):<br /><ul><li>Decrease turbulence
  30. 30. Highest venous flow
  31. 31. Minimal venous hypertension
  32. 32. More difficult than side to side</li></ul>4. End to end:<br /><ul><li>Least arterial steal and venous hypertension
  33. 33. Lowest flow of the four configurations</li></li></ul><li>Procedures <br />Side to side radiocephalic fistula:<br />Oblique or longitudinal incision is made overlaying the selected anastomotic site.<br />Cephalic vein is located and isolated from the surrounding subcutanious tissue<br />Venous tributaries are ligated and divided to improve mobility of the vein<br />Incision is made in the deep fascia of the forearm and the radial artery exposed carfully<br />Radial artery carefully mobilized , ligating the muscular branches and isolating it from the surruondhig tissue<br />Adequately mobilized length of both vessels are necessary so that they rest side by side without tension<br />
  34. 34.
  35. 35.
  36. 36.
  37. 37.
  38. 38.
  39. 39. Procedures<br />Side to side brachiocephalic fistula:<br />When construction of fistula at the wrist is not possible , anastomosis of the cephalic vein to the brachial artery immediately proximal to the cubital fossa will provide satisfactory access<br />A transverse incision is made proximal to the cubital fossa <br />The brachial artery is mobilized untill it reaches the bifurcation at the level of bicipital tendon<br />The median nerve lies medial and posterior to the artery and should be carefully protected<br />The anastomosis is similar to the radiocephalic but the veenotomy and arteriotomy should be limited to about 5 – 7 mm to minimize the incidence of steal syndrome<br />
  40. 40. Procedures<br />Basilic vein – radial artery fistula:<br />Mobilization of the basilic vein in the forearm and anastomosis of its end to the radial artery also may be used to provide access for heamodialysis<br />The basilic vein is mobilized along the ulner border of the forearm to about the middle of the forearm.<br />A subcutanious tunnel is prepared between the vein and the radial artery<br />These vessels are then anastomosed attaching the vein end to either the end or the side of the artery<br />
  41. 41. This technique of fistula formation may be used in patients who have an obliterated cephalic vein or distal radial artery<br />It is possible to anastomose the basilic vein to the ulner artery, however if there has been a previous radiocephalic fistula in that arm , there is a danger that circulation in the hand will be compromized<br />
  42. 42.
  43. 43. Complications<br />
  44. 44. complications<br />Failure:<br />The most frequently complication is that of early failure <br />Reported incidence of up to 27% <br />Such a complication may be a result of :<br />Thrombosis: (more in)<br /><ul><li>DM
  45. 45. erythropoietin</li></ul>Failure to mature and achieve an adequate flow rate to maintain dialysis:<br /><ul><li>Techniqal problems in constructing the anastomosis
  46. 46. A sclerotic vein segment in the forearm because of previous venisection
  47. 47. Inadequate venous size
  48. 48. Cacification of the arterial wall</li></li></ul><li>complications<br />So when thrombosis is suspected by clinical evaluation , further assessment can be made by :<br />Angiogram<br />US<br />Surgical thrombectomy is done by making a small venotomy and using a fogarty balloon catheter to remove the thrombus<br />
  49. 49. complications<br />Aneurysm:<br />Pseudoaneurysm formation may occur at puncture sites following dialysis<br />However , the incidence is much lower than that of prosthetic grafts<br />True aneurysm are much rare but have also been reported in few occasions in the vein distal to the anastomosis <br />These can be treated with resection and either <br />end to end anastomosis <br />Placement of short segment graft<br />
  50. 50.
  51. 51. complications<br />Infection:<br />Infection of autogenous fistula are rare compared to prosthetic graft<br />They present with:<br />Fever<br />Erythema<br />Tenderness<br />And complications (such as thrombosis and aneurysm )<br />The most common infecting organism is staph aureus<br />Managed by systemic antibiotics , drainage and revision as necessary<br />
  52. 52. complications<br />Ischemic changes:<br />Steal symptoms may occur in around 4% of patients with autogenous fistula<br />The incidence is higher in :<br />Diabetic patients<br />Atherosclerotic patients<br />And in anticubital fistulas<br />The symptoms may only manifested during dialysis and as such may be managed by observation and by using low flow rate<br />At its worst , gangrene may occur requiring amputation<br />To avoid the problem of retrograde flow through the palmar arch in wrist fistula , ligation of the radial artery distal to the anastomosiscan be performed . Alternatively an end to end anastomosis can be constructed<br />
  53. 53.
  54. 54. complications<br />Venous hypertension:<br />Another vascular complication is the development of venous hypertension syndrome , where the hand distal to the fistula become swollen and uncomfortable with thickning of the skin and hyperpigmentation<br />Venous hypertension may be avoided by forming an end to end anastomosis<br />Or to ligate the enlarged venous tributaries causing the hypertension of the distal digits , so preserving the fistula<br />
  55. 55. complications<br />Cardiovascular complication:<br />High output cardiac failure is a rare complication which may occurs particularly in patients displaying a combination of low heamatocrit, cardiomyopathy from diabetes and the presence of high flow fistula<br />Treatment usually involves sacrificing the fistula<br />
  56. 56. Care of A-V Fistula<br />Keep the fistula arm raised on a pillow to reduce swelling. <br />The dressing should remain intact and dry at all times. <br />As soon as post operative pain has subsided, start arm exercises <br />Do not allow blood pressure, blood taking or intravenous administration on the fistula arm. <br />Check for thrill<br />
  57. 57.
  58. 58. Thank<br /> you<br />