intergumentary system

patho

layers of the skin

• epidermis

• dermis

• hypodermis (subcutaneous)

medication takes slower to absorb than in the muscle or epidermis

hypodermis med administration

dermal appendages

• nails

• hair

• sebaceous glands

• eccrine and apocrine sweat glands

blood supply is limited to what

to the dermis

eccrine glands

distributed through the whole body but more abundant at hand, feet, and forehead and produce less sweat than aprocrine

apocrine

produce less sweat but open into the hair follicles so they’re more present in mons pubis, axillae, etc.

primary lesions

• macule

• papule

• patch

• plaque

• wheal

• nodule

• tumor

• vesicle

• bulla

• pustule

• cyst

• telangiectasia (spider veins)

secondary lesions

always a result of modification of a primary lesion

• scale

• lichenification

• keloid

• scar

• excoriation

• fissure

• erosion

• ulcer

• atrophy

macule

• flat lesions

• different in color and texture from its surrounding tissue

• <1 cm in size

• ex: petechiae, flat nevi

patch

• flat lesions

• a large macule

• >1 cm

• ex: cafe au lait spot, mongolian spot etc

papule

• small, solid, elevated lesion

• <1 cm in diameter

• ex: elevated nevus (mole), wart, bug bite

plaque

• elevation of skin

• >1 cm in diameter

• often times silvery and scaly

• ex: psoriasis

pustule

• a visible accumulation of purulent fluid under skin

• <1 cm in diameter

• ex: acne, impetigo

vesicle

• a circumscribed elevation of the skin

• contains serous fluid

• <1 cm in diameter

• ex: herpes simplex, varicella, zoster

nodule

• solid mass of skin

• observed as an elevation or can be palpated

• >1 cm in diameter

• often extends into the dermis (deeper)

• ex: dermatofibroma, xanthoma

bulla

• circumscribed elevation containing fluid

• >1 cm in diameter

• extends only into the epidermis

• ex: burns, blisters

wheal

• elevated white or pink compressible papule or plaque

• a red, axon-mediated flare often surrounds it

• commonly seen in allergic reactions

• ex: PPD test, urticaria

cyst

• any closed cavity/ sac

• contains fluid or semisolid material

• ex: sebaceous cyst, cystic acne

pressure ulcers

• ischemic ulcers resulting from any unrelieved pressure on the skin, causing underlying tissue damage. Decubitus ulcers develop when pressure interrupts the normal blood flow to the skin

• causes:

  • pressure

  • shearing forces

  • friction

  • moisture

• usually over bony prominences as the sacrum, heels, ischia, greater trochanters.

• prevention: reposition every 2 hours, optimize nutrition and hydration

suspected deep tissue injury

discolored (purple or maroon) intact skin or blood-filled blister

unstageable

full thickness tissue loss with base of ulcer covered by slough or eschar, or both

inflammatory disorders

atopic dermatitis

contact dermatitis

eczema (atopic dermatitis)

• inflammatory process causes erythema of the skin

• characterized by:

  • severe prurititus

  • lesions with indistinct borders

  • epidermal changes

• associated with IgE antibodies

• hypersensitivity type II

• common with hay fevers or asthma

contact dermatitis (allergic and irritant)

• inflammatory: CD4 and CD8 T lymphocytes are responsible.

• allergic agents: antimicrobials, anesthetics, hair dies, preservatives, latex, adhesives and from plants in the Rhus genus.

• irritant agents: soaps, detergents, organic solvents

• the allergen comes in contact with the skin, binds to a carrier protein to form a sensitizing antigen; non-IgE mediated allergic response

• manifestations

  • erythema

  • swelling

  • pruritus

  • vesicular lesions

• type IV hypersensitivity

papulosquamous disorders

• psoriasis

• pityriasis rosea

psoriasis

• chronic, relapsing,, proliferative, inflammatory skin disorder

• caused by complex interactions between macrophages, fibroblasts, dendritic cells, natural killer cells, T helper, and regulatory T cells

• this epidermis

• turnover happens faster

• cells do not have time to mature or adequately keratinize

• red plaque surrounded by silver scales, the scales cannot be removed, if they are they’ll start bleeding

• activation of T cells increase growth factors

• attract neutrophils and monocytes which activate inflammation factors.

pityriasis rosea

• benign, self-limiting (will go away by itself), inflammatory disorder

• usually occurs during the winter months

• herald patch

  • circular, demarcated, salmon-pink, 3 to 10 cm lesions

• secondary lesions develop within 14 to 21 days and extend over the trunk and upper part of the extremities

skin infections

• fungal

• bacterial

• viral

fungal

• tinea infections: superficial fungal infections.

• fungi causing superficial skin lesions are called dermatophytes

  • ringworm, athlete’s foot. Attach the dead cells. Inflammatory infections

  • deep fungal infections

  • candidasis. Attack living tissue. Normally found on the skin, mucous membranes, in the GI tract, and in the vagina. (not an std)

• fingal disorders are called mycoses: mycoses caused by dermatophytes are termed tinea

  • tinea capitis (scalp)

  • tinea manus (hand)

  • tinea pedis (foot, athlete’s foot)

  • tinea corporis (ring worm)

  • tinea cruris (groin, jock itch)

  • tinea unguium (nails) or onychomycosis

bacterial

• cellulitis

  • infection of the dermis and subcutaneous tissue

• impetigo

  • superficial infection of the skin. Caused by Staphylococcus or streptococci. Highly contagious. Honey-colored crust with a moist erythematous base

viral

• HPV (human papiloma virus)

  • common warts

    • common in children

    • usually on fingers

    • plantar warts (usually on pressure points on bottom of feet)

  • condylomata acuminata (anogenital warts; sexually transmitted HPV)

• HSV (herpes simplex virus)

  • HSV 1 and HSV 2 associated with oral infections or infection of the cornea, mouth, and orolabial- HSV1

  • inflamed and painful vesicles

  • gential infections are more commonly caused by HSV 2

• herpes zoster (shingles) and varcella (chicken pox)

  • caused by the same virus varicella zoster virus (VZV)

  • primary infection followed years later by activation of the virus to cause herpes zoster (shingles)

  • virus remains latet in trigeminal and dorsal root ganglia

which of the following skin conditions is caused by a bacterial infection?

impetigo

benign tumors

• actinic keratosis

• nevi (moles or birthmarks)

actinic keratosis

premalignant lesions composed of aberrant proliferations of epidermal keratinocytes

nevi (moles or birthmarks)

benign pigmented or non-pigmented lesions

skin cancers

• basal cell carcinoma

• squamous cell carcinoma

• malignant melanoma

basal cell carcinoma

• most common cancer in the world

• red macule or papule and may develop a depressed center.

• grows slowly, often ulcerated, develop crusts, and is firm to the touch

• metastasis is rare

squamous cell carcinoma

• usually in sun exposed areas

• second most common human cancer

• in situ or invasive

• may occur as a result of actinic keratosis (premalignant lesions composed of aberrant proliferations of epidermal keratinocytes)

malignant melanoma

• malignant tumor of the skin originating from melanocytes

• most serious skin caner

• ABCDE approach to evaluate

• changing nevi, with new swelling, redness, scaling, oozing or bleeding.

ABCDE’s

asymmetry

borders

change

diameter

elevation

sun exposure

• sun exposure increases the risk of skin cancers

• cumulative sun exposure increases the risk of:

  • basal cell carcinoma

  • squamous cell carcinoma

• severe sun exposure with blistering increases the risk of:

  • malignant melanoma

which of the following skin conditions is benign

actinic keratosis

burns

injury that results from contact and/ or exposure to any thermal, radiation, chemical or electrical agent.

• superficial (first degree)

• superficial partial thickness (first degree)

• deep partial thickness (second degree)

• full thickness (third degree)

• fourth degree

• >20% TBSA considered to be major burn injuries

  • associated with massive evaporative water losses and fluctuations of large amounts of fluid, electrolytes, and plasma proteins into the body tissue

  • burn shock

• cardiovascular system will be affected as cardiac output and cardiac contractibility will be decreased ands there will below capillary perfusions.

• cellular response as Na K pump will be impaired and there will be abnormal concentrations of each

• metabolic response will be affected as there will be a hypermetabolic state, we will beed lots of energy during this state. person will be in imunosuppresant state.

superficial

• epidermis only

• local pain and erythema and blanches with pressure

• no blisters

• heal in 3-6 days with no scarring

• mild to moderate sunburn

superficial partial thickness

• epidermis and some dermis

• blisters and heals in 10-21 days

deep partial thickness

• epidermis and deeper dermis

• blisters and heals in 2-6 weeks, usually without scars

• wet or waxy dry

• MOST painful

• do not remove blisters, the longer they keep them, the least chance of having infections and better healing

full thickness

• epidermis, dermis, and underlying subcutaneous tissue

• wound dry and leathery as eschar develops

• without blisters. Painless

• escharotomies performed to release pressure and prevent compartment syndrome

• e.g. flames, explosion with very high temperature

fourth degree

• full-thickness and deeper tissue

  • epidermis, dermis, and underlying subcutaneous tissue, tendons, muscle, and bone

elements of survival of a major burn

• control airway

• provision of adequate fluids

• nutrition (high-[protein, high-fat, high-calorie)

• meticulous management of wounds with early surgical excision and grafting

• aggressive treatment of infection or sepsis

• promotion of thermoregulation

• monitor circumferential burns for compartment syndrome

compartment syndrome

• characterized by nerve and blood vessel damage or destruction that results from swelling and edema

  • interstitial swelling, pressure on blood vessels causes them to collapse

  • low blood flow with tissue hypoxia and death

  • pain intense

  • typically occurs in arms and legs

• treatment: escharotomy (fasciotomy) to relieve pressure

escharotomy

opening the skin to relieve edema pressure on the blood vessels and nerves. if this isnt done, areas distal to collapse will necrotize and die.