ABSTRACT
The importance of the location of a surgically-created arteriovenous fistula around
the pedicle (both distal and proximal) on the viability of rat skin flaps was investigated.
The animals were randomly divided into four groups. Group 1 included bilateral standard
island groin flaps. The right side flap was used as a control. On the left side, after
elevation of the flap, an X-type arteriovenous fistula greater than 1 mm (up to 2
mm) in length was created distal to the pedicle, and just before the bifurcation of
the common femoral vessels. In Group 2, the flap was an axial-pattern medially-based
peninsular flap, including the same vessels. In this group also, two flaps were elevated
bilaterally, and the right side was used as a control; on the left side, an X-type
arteriovenous fistula the same length as in Group 1 was also created distal to the
pedicle. In both groups, all other branches of the common femoral vessels were kept
intact. In a second part of the study, two other animal groups were used to clarify
the importance of the length of the arteriovenous fistula on the viability of skin
flaps. In Group 3, the model was the same as in Group 1, but the fistula was 1 mm
in length. In Group 4, the length of the fistula was 1 mm, and its location was on
the common femoral vessels proximal to the pedicle, using the same flap model. Flow
values were measured repeatedly using a laser Doppler flowmeter. Histopathologic studies
were also done.
There are three important points arising from these studies. 1). The location of an
X-type arteriovenous fistula around an island skin flap pedicle seems to be more important
than diameter. An arteriovenous fistula proximal to the pedicle is more hazardous
than an arteriovenous fistula distal to the pedicle, regarding island skin-flap viability.
2). However, the length of the fistula is also important, and an arteriovenous fistula
distal to the pedicle, with a sufficiently long length, is not devoid of harmful effects.
It is also clear that the larger the fistula, the greater the systemic effects. 3).
An island skin flap with an arteriovenous fistula distal to its pedicle might be a
useful model to study the relationship between skin-flap viability and edema formation.
KEYWORD
Arteriovenous fistula - pedicle site - axial-pattern skin flaps
