Integumentary System

1. Integumentary System HSTIII 2009-2010

2. Objectives: After completing this unit each student should be able to: • Compare the composition and function of the epidermis with those of the dermis • Describe the functions of the skin. • Describe normal hair, nails, sebaceous glands, and sudoriferous glands and their primary functions.

3. Objectives: • Give examples of the appropriate health history questions for assessment of the skin, hair, and nails. • Describe how to assess thee client’s skin by inspection and palpation. • Differentiate between normal and abnormal skin conditions. • Describe the characteristics of common skin lesions using appropriate terminology.

4. Objectives: • Identify life-threatening drug induced skin eruptions. • Describe the general dermatologic preparations and their indications. • Discuss ectoparasitic diseases and the use of topical ectoparasiticidal drugs in their treatment.

5. Anatomy and Physiology

6. Considered to be both: • (a) Membrane – covers the body • (b) Organ – contains several types of tissue • Largest organ in body - covering (c) 3,000 square inches • About (d) 15% total body weight

7. Tissue: • 3 layers of tissue 1. (e)Epidermis – outermost layer of skin • (f) NOblood vessels or nerve cells (avascular) 2. (g)Dermis – corium or “true skin” • Includes: • Elastic connective tissue • Blood vessels • Lymph vessels • Nerves • Involuntary muscle • Sweat and oil glands • Hair follicles

8. Tissue: • (h) Subcutaneous layer (hypodermis) – the innermost layer • Made of: • Elastic and fibrous connective tissue • Adipose (fatty) tissue • Connects the skin to underlying muscles

9. Fingerprints? • The top layer of the dermis has ridges which form lines or striations on the skin which give us our unique fingerprints

10. Major Organs/Structures • Skin • Sweat and oil glands • Nails • Hair

11. Two Main Types of Glands • (i) Sudoriferous (sweat) glands • Sweat eliminated by these glands contains water, salts, and some body wastes • Sweat is odorless until it interacts with bacteria on the skin • Perspiration (sweating) removes excess water from the body and cools the body

12. Two Main Types of Glands • (j) Sebaceous (oil) glands • Usually open onto hair follicles • Produce sebum (oil) which keeps skin and hair from becoming dry and brittle • Slightly acidic nature helps prevent infection • Oil glands plugged with dirt and oil result in blackheads or pimples.

13. Hair • Consists of a root (which grows in a hollow tube called a (k)follicle) • A (l)hair shaft • Helps protect the body • Covers all body surfaces except the palms of the hands and the soles of the foot

14. (m) Alopecia (baldness) • Genetically inherited • Males (and some females) • Permanent loss of hair of the scalp

15. Nails • Protect the fingers and toes from injury • Made of (n)dead, keratinized epithelial cells • Formed in the nail bed • If lost, nails will regrow if the nail bed is not damaged

16. Functions of Skin

17. (o) Protection –barrier against UV rays and infection, and helps prevent dehydration • (p) Sensory perception – nerves help the body respond to pain, pressure, temperature, and touch sensations • (q) Body temperature regulation • when blood vessels in the skin (r)dilate (get larger) – excess heat can escape • when blood vessels (s)constrict (get smaller) – heat is retained

18. (t) Storage – tissue temporarily stores fat, glucose, water, vitamins, and salts; adipose (fatty) tissue is a source of energy • (u) Absorption – certain substances are absorbed through the skin, such as medicine and nicotine patches; medication patches are (v)transdermal • (w) Excretion – eliminates salt, waste, excess water and heat through perspiration • (x) Production – skin helps produce vitamin D using UV rays

19. Skin Pigmentation

20. Basic skin color is inherited • (y)Melanin – brownish-black pigment produced in the epidermis • Everyone has the same number of (z)melanocytes but genes determine the amount of melanin produced • Freckles are small concentrated areas of melanin • (aa)Albino – absence of color pigments in the skin • Skin has pinkish tint • Hair is pale yellow or white • Eyes lack pigment; are red; very sensitive to light

21. Abnormal Pigmentation:

22. (bb)Erythema – reddish color that can be caused by burns or a congestion of blood in the vessels

23. (cc)Jaundice – yellow discoloration; indicates bile in the blood resulting from liver and gallbladder disease; also seen in diseases that involve destruction of RBC

24. (dd)Cyanosis – bluish discoloration caused by insufficient oxygen; associated with heart, lung, and circulatory diseases or disorders

25. (ee)Chronic poisoning – may cause gray or brown skin discoloration

26. Primary Skin Lesions: Appear on previously healthy skin in response to disease or external irritation.

27. Macules – flat spots on the skin, such as freckles

28. Papules – firm, raised areas such as pimples and the eruptions seen in some stages of chickenpox and syphilis; up to 0.5cm in diameter

29. Vesicles – blisters, or fluid-filled sacs, such as those seen in chickenpox

30. Pustules – pus-filled sacs such as those seen in acne, or pimples

31. Bulla – fluid filled lesion greater than 2cm in diameter; caused by severe poison oak or ivy dermatitis

32. Comedo – plugged pilosebaceous duct, formed from sebum and keratin; blackhead (open comedo); whitehead (closed comedo)

33. Cyst – Semi-solid or fluid-filled encapsulated mass extending deep into the dermis; example is lacrimal cyst

34. Nodule – Firm, raised lesion; extending into dermal layer; deeper than a papule, 0.5 – 2cm in diameter; example intradermal nevus

35. Patch – Flat, pigmented, circumscribed area greater than 1cm in diameter

36. Plaque – Circumscribed, solid, elevated lesion greater than 1cm in diameter; elevation above skin surface occupies larger surface area in comparison with height

37. Wheals– itchy, elevated areas with an irregular shape; hives and insect bites are examples

38. Tumor– Elevated, solid lesion larger than 2cm in diameter, extending into dermal and subcutaneous layers

39. Secondary Skin Lesions: Result from changes in the primary lesion, usually related to the disease process.

40. Crusts – areas of dried pus and blood, commonly called scabs

41. Ulcer – a deep loss of skin surface that may extend into the dermis; may cause periodic bleeding and the formation of scars

42. Atrophy – Thinning of skin surface at site of disorder; aging skin

43. Erosion – Circumscribed lesion involving loss of superficial epidermis; rug burn, abrasion

44. Excoriation – Linear scratched or abraded areas, often self-induced; for example, abraded (scratched) acne lesions, eczema

45. Fissure – Linear cracking of the skin, extending into the dermal layer; for example hand dermatitis (chapped skin)

46. Keloid – Thick, red, or dark firm scar formed by hyperplasia of fibrous tissue; more frequent in African Americans and Asians.

47. Lichenification – Thickened, prominent skin markings caused by constant rubbing;

48. Scale – Thin, dry flakes of shedding skin; for example psoriasis, dry skin

49. Scar – Fibrous tissue caused by trauma, deep inflammation, or surgical incision; red and raised (recent); pink and flat (6 weeks), or pale and depressed (old)

50. Diseases and Abnormal Conditions