Overview of Full-Thickness Skin Grafts
A skin graft is a procedure where a piece of skin is removed from one area of the body (the donor site) and then transplanted to another area (the recipient site) where skin has been lost or damaged. This technique is used when other healing methods, like naturally healing over time, stitching the wound closed, or moving skin from nearby, aren’t good options.
There are two main types of skin grafts. Full-thickness skin grafts (FTSGs) include all layers of the skin, while partial-thickness skin grafts (PTSGs) only include the top layer and part of the second layer.
FTSGs are relatively straightforward for doctors to take from the donor site and secure to the recipient site. They work especially well for areas like the tip of the nose, the bridge of the nose, the side walls and the outer parts of the nose, alongside the eyelids and the ears. It’s best to use skin that closely matches the color, thickness, level of sun damage, and the texture of the surrounding skin at the recipient site.
The benefits of FTSGs are that they don’t change the structure of the recipient site, they’re straightforward for both the doctor and the patient, and the skin is thicker and more resistant to damage. They also tend to have better visual outcomes because they shrink less during healing. However, FTSGs have a higher chance of not being accepted by the body, are more limited in the size and location of the donor site, and require a longer healing process for the donor site.
Anatomy and Physiology of Full-Thickness Skin Grafts
The skin graft, or a piece of healthy skin, can be taken from almost any part of the body, but certain areas are usually more suitable. There are two types of skin grafts. The first one, full-thickness skin grafts, include the entire top and middle layer of the skin. The other type, partial-thickness skin grafts, include all of the top layer but only part of the middle layer of the skin. When doing a skin graft, doctors try to match the skin at the area receiving the graft as closely as possible. Things like the thickness of the skin, the number and size of oil glands, whether there’s hair or not, the color of the skin, and the amount of sun damage are all taken into consideration. Commonly used areas for taking skin grafts include the area front and back of the ear, the area around the collarbone, and the inner arm among others. The grafts are most often used in areas like the eylids, ears, or the tip and sides of the nose.
For the graft to survive, it needs to be able to get blood from the new site, so that site needs to be healthy and have some blood vessels. Providing blood flow from the edges of the wound to the graft can supply up to about 5 mm of the graft. If the area doesn’t have enough blood flow, it can be left to heal for a while to allow for the growth of new, healthy tissue, before the graft is placed. Another option is to move a flap of muscle or soft tissue into the wound base to provide a source of blood for the graft. In the first 24 hours after placement, the graft absorbs fluid from the new site and swells, this stage is known as “plasmatic imbibition.” Fibrin, a type of protein, acts as a natural glue holding the graft in place during this time. Later on, the fibrin is replaced by new, healthy tissue. Blood vessels begin to form connections between the new site and the graft about 48 to 72 hours after the grafting. This process is known as “inosculation.” Full blood flow is restored within 4 to 7 days, and lymphatic flow or flow of the fluid that forms part of the immune system occurs within 7 days. Although feeling in the graft can begin to return 2 to 4 weeks after grafting, it may take several months or even years to fully return to normal.
Why do People Need Full-Thickness Skin Grafts
If your skin won’t heal on its own or close up naturally, or if closing it up with stitches or using a flap of skin from elsewhere on your body isn’t an option, then skin grafts are your next best bet. Skin grafts are especially good at fixing skin damage on areas like the tip of your nose, the bridge of your nose, the nostril surfaces, the sides of your nose, your eyelids, and your ears.
When a Person Should Avoid Full-Thickness Skin Grafts
The success of a skin graft mainly depends on the small blood vessels growing from the recipient site into the graft. Therefore, it’s important that there is a healthy and somewhat blood-rich layer of tissue at the graft site. This is why full-thickness skin grafts (skin grafts that include all layers of the skin) shouldn’t be placed on areas of any size without an existing blood supply. This is especially true if, for example, the area is larger than 1 cm and is showing exposed bone or cartilage – these are not ideal for graft placement.
Also, it’s important to note that smoking can significantly compromise the oxygenation of tissue – basically, smoking restricts the amount of oxygen that can reach the tissue. Because of this, if possible, the patient should stop smoking before the graft is placed.
Equipment used for Full-Thickness Skin Grafts
Before the procedure, the doctor will need:
* A local anesthetic (usually a mix of lidocaine 0.5% and epinephrine 1:200,000, adjusted with sodium bicarbonate) to numb the area
* Small syringes (3 cc)
* Thin needles (30 gauze)
* Antiseptic scrub to clean the skin and prevent infection
* Surgical marker to outline the area
* Foil or similar material to trace the area needing treatment
During the procedure, the doctor will use:
* A sterile drape to keep the area clean
* A scalpel with a #15 blade for making incisions
* Toothed forceps for gripping tissues
* Serrated scissors for trimming fat from graft (a piece of tissue for transplant)
* Suture scissors for cutting thread needed for stitching
* Needle holders for controlling the needle
* Normal saline, a saltwater solution, to clean the area and prevent drying
* Sterile gauze for absorbing fluid or wrapping the operation site
* Absorbable sutures for deep stitches, which will dissolve on their own over time
* Cutaneous suture, which may or may not dissolve, for skin sutures
* Ideally, an electrosurgical device should also be ready for stopping bleeding
After the procedure, the doctor will use:
* Nonstick dressing to cover the wound
* A petrolatum-infused gauze strip or similar material to create a pad over the graft site. This can be sutured or taped securely to apply slight pressure and keep the graft in one place.
* Sterile ointment, the doctor prefers sterile petrolatum over antibiotic ointment because many patients can develop allergies to antibiotics.
* Adhesive dressing that’s hypoallergenic and flexible. This sticks to the skin and keeps the bandage in place.
* Additional adhesive liquid can also be used to secure the bandage even further.
Who is needed to perform Full-Thickness Skin Grafts?
A skin graft procedure where the complete thickness of the skin is used can be done by two medical specialists: a main surgeon and another doctor who assists them. This means that it requires a team of just two people – a skilled surgeon who leads the operation, and a surgical assistant who helps the surgeon in performing the procedure safely and effectively.
Preparing for Full-Thickness Skin Grafts
When a skin graft is needed, the doctors select a part of the body that has healthy skin and matches the area needing the graft. They prefer areas without much scarring for this. To make sure the graft fits perfectly, the doctors create a sort of pattern or stencil of the wound. They use a flexible material, like foil, to make this pattern. This pattern is then placed on the area of good skin (donor site) and traced with a surgical pen.
Once the doctors have a clear guide to follow, the donor site and the area getting the graft are numbed with a local anesthesia. This helps to lessen any discomfort during the procedure. Then, everything is cleaned and prepared following standard hygiene practices to avoid any infection. This way, the skin grafting process is done as safely and effectively as possible.
How is Full-Thickness Skin Grafts performed
Once the skin graft is collected, it should be cleaned up. This means removing any leftover fat and hair if there are any present. Then the skin graft is securely attached using a series of single stitches, and the area where the graft was taken from is carefully stitched up in layers. This is especially important in cases where the surgery was done on the nose. Sometimes, the surgeon may partially close the surgical wound and take a small triangular piece of nearby skin, known as a Burow’s triangle, to help move the tissue around. This tiny piece of skin can then be used as a full-thickness skin graft to help repair the rest of the wound.
The grafted skin is generally left in place for one week. This skin graft has to stay directly in contact with the underlying wound and should stay still during this time. Additional stitches, also known as basting sutures, may be placed within the graft to keep it attached to the wound. It’s also important to put a firm bandage on the surgical site, which can be with or without a stitched bolster, which is a padded dressing.
The patient should avoid injuring the site and should not perform any intense physical activities for at least 2 weeks after the surgery. This is to ensure the new skin graft can heal properly.
Possible Complications of Full-Thickness Skin Grafts
Full-thickness skin grafts, or simply skin grafts, might sometimes not work entirely or partially. This could happen due to a condition called hematoma where blood collects outside the blood vessels, or due to infection, smoking, or excessive use of a special surgical tool called the electrocoagulator during the surgery. Sometimes, when your body tries to reject the new skin graft, the area might become necrotic, or in other words, the tissues may die off.
If this happens, doctors usually prefer not to remove the graft but leave it there to act as a framework for new skin to grow upon. For the graft to work, it’s crucial that neither the graft itself nor the area where it’s placed is infected.
If you’re a smoker, especially a heavy smoker (more than one pack a day), it’s important to know that you have thrice the risk for your graft not working, specifically having necrotic tissues. Therefore, it’s highly recommended to stop smoking for at least two days before and a week after the surgery.
Finally, consulting with a hematologist before the operation, the doctor who specializes in blood and its diseases, is a smart move to make sure everything goes smoothly and the graft works properly.
What Else Should I Know About Full-Thickness Skin Grafts?
If you have a wound that won’t heal well by itself or won’t benefit much from stitches or a skin flap procedure, a full-thickness skin graft might be a good option. This is a procedure where doctors take skin from one area of your body to cover and help heal the wound in a different area. The goal is to provide better healing and recovery for your wound.
