Line 1: |
Line 1: |
− | == Introduction<br> == | + | {{review}} |
| + | == Introduction == |
| + | As the name implies, an arteriovenous fistula is an abnormal direct connection between an artery and a vein. This connection causes the capillary circulation to be completely ignored. We will concentrate on peripheral fistulas here. The consequences of an arteriovenous fistula are the following: |
| + | :Increased blood return to the right heart raises cardiac output |
| + | :Decreased blood perfusion at the affected site |
| + | :Venous hypertension will arise |
| | | |
− | As the name implies, an arteriovenous fistula is an abnormal direct connection between an artery and a vein. This connection causes the capillary circulation to be completely ignored. We will concentrate on peripheral fistulas here. The consequences of an arteriovenous fistula are the following; Increased blood return to the right heart raises cardiac output, there is decreased blood perfusion at the affected site and venous hypertension will arise.<br>
| + | Some causes of an arteriovenous fistula include trauma, surgery and neoplasia. |
| | | |
− | Some causes of an arteriovenous fistula include trauma, surgery and neoplasia amongst others.
| |
| | | |
− | <br>
| + | == Clinical Signs == |
| | | |
− | == Clinical Signs<br> ==
| + | Signs depend on where the AV fistula has formed. Some signs include subcutaneous [[Oedema|oedema]], presence of a warm swelling, inflammation, pain, palpable vibration (thrill) over fistula, increased pulse & heart rate, an audible continuous murmur over the fistula site and the Branham sign (decreased heart rate with surgical occlusion of blood flow to fistula). |
| | | |
− | Signs depend on where the AV fistula has formed. Some signs include subcutaneous oedema, presence of a warm swelling, inflammation, pain, palpable vibration (thrill) over fistula, increased pulse & heart rate, an auudible continuous murmur over the fistula site and the Branham sign (decreased heart rate with surgical occlusion of blood flow to fistula). <br>
| |
| | | |
− | <br>
| + | == Diagnosis == |
| | | |
− | == Diagnosis<br> ==
| + | Clinical signs and history are quite indicative of the condition. |
| | | |
− | Clinical signs and history are quite indicative of the condition. <br>
| + | '''Angiography''' can be performed and an abnormal direct connection between an artery and a vein will be found. '''Ultrasonography''' can also be used to demonstrate the presence of abnormal flow. |
| | | |
− | Angiography can be performed and an abnormal direct connection between an artery and a vein will be found. Ultrasonography can also be used to demonstrate the presence of abnormal flow.
| |
| | | |
− | <br>
| + | == Treatment and Control== |
| | | |
− | == Treatment and Control<br> ==
| + | Treatment is to surgically ligate the abnormal vessels to and from the fistula area. Another possible procedure would be amputation of the limb in severe cases. |
| | | |
− | Treatment is to surgically ligate the abnormal vessels to and from the fistula area. Another possible procedure would be amputation of the limb in severe cases.<br>
| |
| | | |
− | <br>
| + | == Prognosis == |
| | | |
− | == Prognosis<br> ==
| + | Good with complete ligation and cessation of blood flow through the fistula. Poor if surgical ligation is unsuccessful at stopping blood flow through the fistula. |
| | | |
− | Good with complete ligation and cessation of blood flow through the fistula. Poor if surgical ligation is unsuccessful at stopping blood flow through the fistula.
| |
| | | |
− | <br>
| + | == References == |
| | | |
− | == References<br> ==
| + | Ettinger, S.J. and Feldman, E. C. (2000) Textbook of Veterinary Internal Medicine Diseases of the Dog and Cat Volume 2 (Fifth Edition) W.B. Saunders Company |
| | | |
− | Ettinger, S.J. and Feldman, E. C. (2000) Textbook of Veterinary Internal Medicine Diseases of the Dog and Cat Volume 2 (Fifth Edition) W.B. Saunders Company<br>Ettinger, S.J, Feldman, E.C. (2005) Textbook of Veterinary Internal Medicine (6th edition, volume 2)W.B. Saunders Company<br>Fossum, T. W. et. al. (2007) Small Animal Surgery (Third Edition) Mosby Elsevier <br>
| + | Ettinger, S.J, Feldman, E.C. (2005) Textbook of Veterinary Internal Medicine (6th edition, volume 2)W.B. Saunders Company |
| | | |
− | <br>
| + | Fossum, T. W. et. al. (2007) Small Animal Surgery (Third Edition) Mosby Elsevier |
| | | |
− | <br>
| |
| | | |
− | <br>
| |
| | | |
− | [[Category:Vascular_Diseases_-_Dog]] [[Category:Vascular_Diseases_-_Cat]] [[Category:Arterial_Pathology]] [[Category:To_Do_-_Review]] | + | [[Category:Vascular_Diseases_-_Dog]] [[Category:Vascular_Diseases_-_Cat]] [[Category:Arterial_Pathology]] [[Category:Expert_Review]] |