1. Dr. Karen Coker Tennessee State University
Integumentary System
Dr. Karen Coker
Tennessee State University

2. SKIN
Skin reflects one’s personality and character Much can be learned just by looking at an individual’s skin

3. SKIN
Wrinkles indicate mood, age, social habits, overexposure to the sun

4. Skin Tone
Color reflects one’s ethnicity as a result of the melanin content

5. Melanocyte

6. Skin Texture
The skin’s texture indicates one’s life occupation from repeated mechanical forces or weather exposure

7. Reflects Emotion-gestures
Skin reflects one’s emotions as it moves fluidly with the underlying muscles and connective tissue.

8. SKIN
Skin abnormalities can be a response to a disease process, injury, allergy, or medication
Contact Dermatitis from a silver watch band

9. Wounds Skin wounds that are partial thickness heal with skin
Skin wounds that are full thickness heal with scar tissue

10. Skin-Two Distinct Layers
Epidermis and dermis
Largest organ
Functions
Temperature regulation
Excretion of sweat and electrolytes
Oil secretion
Vitamin D synthesis
Sensation

11. Skin-Two Distinct Layers
Epidermis
Outermost layer
Waterproof
Protects body from infection

12. Skin-Two Distinct Layers
Dermis
Contains nerves, vessels, lymphatics, elastic fibers, sweat and sebaceous glands, hair follicles
Contains collagen fibers that give skin its strength and elasticity

13. Skin
Subcutaneous tissues and fat

14. 5 layers to the epidermis
Stratum corneum-dead cells that shed
Stratum lucidum-soles and palms (thickness)
Stratum granulosum
Stratum spinosum
Stratum basale-produces epidermal cells

15. Cell adherence Epithelium: Cells bind the skin cells to each other
Cells bind the stratum basale of the epidermis to the dermis

16. Dermal-epidermal Junction
Dermal papillae and epidermal pegs meet together to create a bond that will withstand friction and shear forces to the skin

17. Sensation Informative Protective
Skin has sensors that pick up information and send that information to the brain
If the skin senses danger or pain, a quick reflex to move away from the pain protects you from further injury

18. Skin Renewal
New skin cells (keratinocytes) are located in the epidermis in the stratum basale
If skin needs to heal, the fibroblasts in the dermis are the major cells involved

19. Prevention of fluid loss
The outer most layer of the epidermis is the stratum corneum
It is a barrier to fluid loss
Homeostasis (balance) is maintained
Water loss can cause dry skin or irritant dermatitis

20. Immunity In addition to the physical barrier skin provides,
Langerhans cells (stratum spinosum in the epidermis: are alerted by foreign microbes that come on the skin)
pH (acidic pH of that is an “acid mantle” for a chemical barrier to microbes)
Antimicrobial peptides and lipids (prick the microbe cell membrane and destroy its integrity, making it inactive)

21. Thermoregulation Skin responds to changes in temperature
Dermal blood vessels:
arteries constrict when cold to preserve inner body heat
In heat, arteries dilate to allow more blood to circulate near the skin surface and dissipate the heat
Sweat glands
Eccrine sweat glands allow fluid to evaporate
(apocrine sweat glands are stress related: armpits, groin)

22. Protection from Ultraviolet Rays
Presence of melanin
Provides color variation
Provides protection of underlying tissue from the UV rays of the sun

23. Synthesis and Storage of Vitamin D
Vitamin D is necessary for calcium metabolism and bone formation
Stratum basale and stratum spinosum have keratinocytes that secrete Vitamin D
Process is stimulated by sunlight
At least 10 min per day is recommended

24. Aesthetics and Communication
Appearance and sexual attraction
Skin color
Texture
Hyper/hypopigmentation
Apocrine sweat glands in the armpit and groin are dependent on sex hormones and they secrete sex pheromones that can influence behavior

25. Wound Healing
Primary Intention: incision is sutured or fibrin glued or staples back together
Delayed primary intention: wounds left open a few days, then sutured
Secondary Intention: healing by letting it close on its own: inflammatory response, granulation tissue formation, re-epithelialization
Partial thickness wounds: epithelial cell mitosis and migration

26. Wound Healing Hemostasis: blood clot formation (6-12 hours)
Inflammation (1-7 days)
Invaders killed
Wound debridement
Neo-angiogenesis
Proliferation (6 days-8 weeks)
Maturation/Remodel (2 weeks -2 years)

27. Hemostasis: blood clot formation (6-12 hours)

28. Inflammation (1-7 days)

29. Proliferation (6 days-8 weeks)
Eschar
(needs debridement)
Neo-genesis
Proliferation

30. Maturation/Remodel (2 weeks -2 years)
Re-epithelialization of a wound: skin cells grow over the granulation tissue to seal the wound

31. Reference
Text and Atlas of Wound Diagnosis and Treatment by Rose L Hamm McGraw-Hill Education.