Arterio venous fistula is defined as an abnormal communication between an artery and vein. It is of two types 1.Congenital - is arteriovenous malformations 2.Acquired - Trauma is the main cause. It is commonly seen in limbs , either whole or part, toes , fingers, lungs, brain, other organs like bowel and liver

1. en love da Homoeopathy
ARTERIOVENOUS
FISTULA

2. ARTERIOVENOUS
FISTULA

3. ARTERIOVENOUS FISTULA
(AVF)
DEFINITION
• It is an abnormal
communication betweenan
arteryand vein.
TYPES
• 1. Congenital—is
arteriovenous malformation.
2. Acquired (Trauma is
commoncause).

4. SITE
• Limbs, either part or
whole of the limb is
involved.
• It may be localisedto toes
or fingers.
• Lungs.
• Brain—incircle of Willis.
• Other organs likebowel,
liver.

5. CLINICALFEATURES
• Structural changes in the
limb:
↓
Limbis lengtheneddue to
increasein blood flow
↓
since developmental period.
↓
Limb girthis also increased.
↓
Limb is warm.
↓
Continuous thrill & continuous
machinerymurmur all over the
lesion.
↓
Dilatedarterialised varicose
veins
↓
due to increasedblood flow &
valvular incompetence.
↓
bone erosionor extensionof
AVF into the bone as such.

6. • Physiological changes
↓
Because of the hyperdynamic
circulation
↓
there is increasedcardiacoutput
↓
congestive cardiac failure
COMPLICATION
• Haemorrhage
• Thrombosis
• Cardiac failure (CCF)

7. INVESTIGATION
• Angiogram—MR
angiogramis ideal.
• Doppler study.
• X-rayof the part.
• ECG
• Echocardiography
TREATMENT
• Conservative
• Sclerotherapy
• Compression
• avoiding injury.
INDICATIONS FOR
INNERVATION
• Absolute: Haemorrhage,
ischaemia, CCF.
• Relative: Pain, functional
disability, cosmesis, limb
asymmetry.
• Emergency: Torrential
bleeding usuallyafter
trauma (example—road
traffic accidents

8. ACQUIREDARTERIOVENOUS
FISTULA
CAUSES
• Trauma in (most common
cause): Femoral region.
Popliteal region. Brachial
region. Wrist. Aorta—
vena caval. Abdomen.
• After surgical intervention
of major vessels.
• Therapeutic: For renal
dialysis, AVF is created
(Cimino fistula) to achieve
arterialisation of veins and
also to have hyperdynamic
circulation.
• It is done to have easy and
adequatevenous accessfor
long time haemodialysis.
• Common sites
• Wrist
• Brachial
• Femoral region

9. PATHOPHYSIOLGY
Physiological changes:
• Cardiac failure due to
hyperdynamiccirculation.
Structural changes:
• Changes at theLevel of
Fistula
↓
Blood flows fromhighpressure
arteryto low pressurevein
↓
causing diversion of most of the
blood.
↓
Between the artery and vein, at
the site of fistula

10. ↓
dilatation develops with
formation of fibrous sac called
as Aneurysmal sac.
↓
This presents as warm, pulsatile,
smooth, soft, compressible
swelling at the site
↓
with continuous thrill and
continuous machinerymurmur

11. • Changes Belowthe Level of
the Fistula
↓
Because of diversionof arterial
blood distal part
↓
becomes ischaemic
↓
Because of highpressure
arterialisationof veins
↓
& valvular incompetence occurs
causing varicoseveins.

12. • Changes Proximal to the
Fistula
↓
Hyperdynamiccirculation
causes cardiac failure.
↓
Cardiac failure may be very
severe in traumaticAVF
↓
If pressure is appliedto the
arteryproximal to the fistula,
↓
swelling will reduce in size
↓
thrill and bruit will disappear,
pulserate and pulsepressure
becomes normal.
↓
This is calledas Nicoladoni’s
signor Branham’s sign.

13. INVESTIGATION
• Doppler
• Angiogram.
• ECG
• Echocardiography.
TREATMENT
• Excision of fistula and
reconstructionof artery
and vein with graft.
• Done in early stages—
larger vessels.
• Venous or Dacrongraft is
used.

14. REFERENCE
1. SRB's Manual of Surgery
by SriramBhat M
2. A Manual on Clinical
Surgery by Das
3. A Concise textbookof
Surgery by Das

15. A
Special Thanks
To A Very
Special Doctor