Compromised Skin Grafts and Flaps
Reconstructing complex wounds is accomplished
by shifting or transferring tissues to the wound from a different part of
the body. A “skin graft” is the transfer of a portion of
the skin (without its blood supply) to a wound. A “flap”
consists of one or more tissue components including skin, deeper
tissues, muscle and bone. Flaps are transferred with either their own,
original blood supply (pedicle flap) or with detached blood vessels which
are attached at the site of the wound (free flap).
Skin grafts survive as oxygen and nutrients
diffuse into them from the underlying wound bed. Long-term survival
depends on a new blood supply forming from the wound to the graft.
When the wound bed does not have enough oxygen supplied to it, the skin
graft will at least partially fail. Common causes for this are
previous radiation to the wound area, diabetes mellitus, and certain
infections. In these situations, the availability of oxygen in the
wound bed can be increased with hyperbaric oxygen therapy (HBO2)
in preparation for skin grafting. Additionally, HBO2 can be
used after skin grafting to increase the amount of the graft that will
survive in these compromised settings.
Flaps also require oxygen and nutrients to
survive. The outer, visible portion (usually skin) is furthest from
the source of blood supply for the flap. This is the area most likely
to be compromised by inadequate oxygen. Factors such as age,
nutritional status, smoking, and previous radiation result in an
unpredictable pattern of blood flow to the skin. If a flap is found to
have less than adequate oxygen after it has been transferred, HBO2
can help minimize the amount of tissue which does not survive and also
reduce the need for repeat flap procedures.
Partial or complete failure of the wound reconstruction is very difficult for a patient and also very expensive. HBO2 can help by assisting in the preparation and salvage of skin grafts and compromised flaps.