Skin Grafts
Skin grafts are used in treating partial thickness and full thickness burns.
Early surgical removal (excision or debridement) of burned skin followed
by skin grafting reduces the number of days in the hospital and usually
improves the function and appearance of the burned area, especially when
the face, hands, or feet are involved. However, if the patient’s life
is in danger skin grafting is usually postponed.
The best skin grafts come from the patient’s own unburned skin (donor
sites). The grafts (called autografts) will ideally come from locations
that are not ordinarily visible, such as the buttocks or upper thighs, because
the donor sites will not be normal in appearance after they heal. However,
the size of grafts that are needed and the location of burns will also determine
where the grafts are taken from.
An instrument called a power dermatome is set to a particular depth and
shaves off a uniform layer of healthy skin to graft onto a burned site.
The thickness of the skin graft depends on the area needing the graft. Most
grafts are “split” (partial) thickness. The donor site for a
split thickness graft does not need to be surgically closed and will ordinarily
form a new top layer of skin in 10 to 14 days. In many cases donor sites
can be used again for additional grafts. Because skin around a split thickness
graft usually contracts and grows tighter, full thickness skin grafts may
be needed in areas such as around the eyes, where tight skin could prevent
the eyelids from fully closing. A full thickness donor site needs to be
surgically closed. For large areas requiring skin grafts, a “mesh”
is made out of multiple skin grafts. The area to be grafted has the dead
skin removed (debrided), often with a power dermatome, in preparation for
the graft.
Can anything be done if the burn patient doesn’t have enough healthy
skin for needed skin grafts?
The patient’s donor sites can often be used more than once for grafts
after a new layer of skin forms on the donor site, although there is a limit
to how many grafts can be taken from the same site. Grafts from skin banks
and other living and synthetic grafts are also available.
Skin banks
Skin banks are similar to blood banks. They test for communicable diseases
and store skin from individuals who agreed to be organ donors before dying.
The donor skin (called an allograft) is preserved in a solution or frozen.
Grafts from skin banks are used as a temporary covering to protect against
infection, reduce pain, reduce fluid loss, and allow the tissues underneath
to heal. However, because the body’s immune system recognizes an allograft
as being foreign, it rejects the graft in 1 to 3 weeks. It is then removed.
High tech skin grafts and artificial membranes
“Biotechnology” has recently produced new types of skin grafts.
CEA (cultured epithelial autograft) uses living skin cells from the burn
patient to grow new skin cells in sheets in a laboratory. Because the skin
cells come from the patient, they are not rejected and form a permanent
new skin layer. The sheets of CEA are very thin (10 – 15 cells thick)
and fragile; they have the strength when first applied of wet tissue paper
and are easily torn. In patients with massive burns, CEA produces a better
cosmetic result than if it weren’t used, but CEA patients often require
longer hospitalizations and more surgeries to release contractures because
of the need to reduce movement to avoid damaging the delicate grafts until
they are established. Products like Integra use products from animals, including
collagen and condroitin, in combination with silicone to form a synthetic
skin substitute as a temporary covering for massive burns.
Our burn research information page has
news about medical research. And our long-term
care page talks about other issues that come up for many patients that
receive skin grafts.
