Objective: Describing tissues in the Integumentary system and their function.

My project was on The Integumentary system and the stages of wound healing utilizing a skin graft. I shared an experience that I had personally gone through as part of this project. For the creative portion of this project, I created a cake outlining each layer of the Integumentary system. if you zoom in on the image you will be able to see the different levels of the system clearly with all the parts involved in each layer of the skin. The images at the bottom of the poster are my stages of healing through the skin graft process and include a before and after image of the graft donor site.

The integumentary is your skin. It protects the external and internal parts of your body, and is the largest bodily organ comprising about 16% of a persons normal body weight. It also provides lots of nerve fibers into the millions used for sensation, thermoregulation for when your body gets too hot or too cold. It synthesizes vitamin D which we use for our bones. The skin helps our psychological well being if it is functioning normally. It excretes waste through our glands, give us our pigmentation, and is a blood storage unit. Did you know that your skin holds about 5% of your entire blood volume.

There are three major layers of the integumentary system, The epidermis, dermis, and hypodermic layers. The epidermis which is the top layer that you can see. There are many layers or stages of the epidermis, the bottom most layer is the Basal layer that is the factory where most of the new cells are created. Most of the cells in the epidermis are called Keratinocytes. Theses cells are constantly being replaced. Your epidermis replaces itself every 4-6 weeks. Which is why when you get a tattoo, the needle has to go very deep into the dermis. The epidermis gets its energy from diffusion from the blood vessels in the dermis. As the keratinocytes move from the bottom to the top layer they eventually die. The dermis is the where all the “work” is done. The Dermis is filled with many different types of connective tissues. It also has the hair follicles which are very important in the growth of new skin. Then there is the subcutaneous or the Hypodermis which stores fat for energy storage, shock absorption and helps anchor the skin. The skin is very resilient. When I underwent a procedure that went horrible wrong. It left the skin of my core without blood, and the skin died pretty quickly when it went without getting the oxygen and nutrients that it needed to survive. We had to remove all of the dead tissue and eventually after months of healing I was left with skin that was clean and very vascularized and ready for a skin graft to help repair the skin.

From learning about the skin cells we know that the epidermis or outermost layer of the skin provides barrier protection, nerve endings, and merkle cells, Langerhans cells, and melanocytes. Skin Structures including sweat glands, hair follicles, and sebaceous glands. They are epidermis derivatives that are also in the dermis. Stem cells from the hair follicles are responsible for the re-epthlialization of the skin graft donor site. My healing process of the donor site went very well you can hardly tell. The Demis is the fibrous layer composed of collagen, elastins. The upper part of the dermis is the papillary layer it has the plexi of the blood vessels and nerves. The plexi provides nutrients to the epidermis through diffusion. The dermis provides the strength and stability in the the split thickness skin graft. Skin grafts are used for a lot of things including burns, wound healing and even frost bite.

For my situation, I had a what is called a split thickness graft. Which means the doctor removed all of the epidermis and part of my dermis off a layer of good skin off of my leg and moved it to the hole in my stomach (that is called a Autograft). He used a meshing process so that the skin won’t collect fluids under the graft and would not be able to take to the clean and well vascularized wound. The doctor stapled the mesh and skin to keep them in place. Along with using a wound vac which uses negative pressure to stabilize the graft and increase blood flow in the wound and promote healing. The Doctor put the graft on the wound bed with the dermis side down. If he put it down epidermis side down, the graft wouldn’t take. The wound needs the connective tissues that are in the dermis. There are a few steps to rejuvenate the skin. It is called Fibrin adhesion, Imbibition, Inosculation, and Neovascular . First thing the skin sticks to the wound with Fibrin adhesion then Imbibition which is a flow of fluids from the wound to the skin graft which takes nutrition from diffusion into the newly grafted skin. Inosculation while the blood vessels from the wound goes into the blood vessels from the skin graft when the skin graft turns pink usually takes about 48 hours. The Revascularization which has many different theories the neovascularization theory is of the new vessels ingrowth into the graft from the recipient wound bed. Then comes the remodeling so the skin graft looks as good as it can and overtime softens and flattening. Without the skin graft it would have taken me several months to years to close that wound leaving me open to get infected causing more issues in my life. I am happy to be alive. I have scars that are a constant reminder to me about what it most important in life. Thank you for reading.