Nurse Caring Concepts 1A
Skin Integrity, Wound Healing,
Inflammation and Infection
Week 12, November 3, 2003
Factors Affecting Skin Integrity
• Adequate perfusion depends on:
– Effective heart pumping
– Adequate blood volume
– Patent, functioning blood vessels
– Adequate capillary blood flow
• Any alteration in these factors can cause skin to
have abnormal color, texture, thickness,
moisture & temperature or result in ulcerations
Braden Scale: Pressure Ulcer Risk Predictor
• Sensory Perception: pt’s ability to respond to
pressure-related discomfort
• Moisture: degree to which skin exposed to
moisture
• Activity: degree of physical activity
• Mobility: ability to change & control body
position
• Nutrition: usual food intake pattern
• Friction & Shearing Force: amount of friction &
shearing force exposure
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Skin Ulcerations
• Leg & foot ulcers: r/t impaired venous/arterial
function in lower extremities
• Stasis dermatitis: eczema & rash r/t impaired
venous return, blood pooling & edema
• Pressure ulcers: decubiti r/t impeded capillary
blood flow from pressure
– Usually over bony prominences (sacrum,
coccyx, heels & elbows are common sites)
– Staged from I - IV according to development
Factors Affecting Integumentary Function
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Nutrition: protein, calories, vitamins & minerals
Lifestyle & habits: hygiene, UV exposure
Epidermis condition: intact, normal moisture
Allergy: may irritate, redden & blister skin
Infections: disrupt skin integrity in many ways
Abnormal skin growth rate: benign or malignant
Systemic disease: peripheral vascular disease
Trauma: accidental or surgical wounds
Exposure: heat, electricity, chemicals or radiation
Manifestations of Alterations in
Integumentary Function
• Pain: deep pressure ulcers usually cause less
pain
• Pruritis (itching)
• Rash: temporary skin interruption
• Lesion:
– Involves loss of structure or function of tissue
– Classified according to characteristics &
distribution (e.g., wheal (hive); pustule (acne);
crust (scab); excoriation (scratch)
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Wound Categories
Broad Categories:
• Acute: knife, burn,
surgical incision etc
• Chronic: persists past
usual healing time
• Open: break in the
skin; tissue damage
• Closed: soft tissue
damage; no skin break
Surgical Classifications:
• Clean: low infection
risk
• Clean/contaminated:
infection risk
• Contaminated: high
infection risk
• Infected: pathogens
present, signs of
infection
Sublethal Cell Injury
• Altered cell function without cell death:
– Hypertrophy: increase in cell size
– Hyperplasia: increase in number of cells
– Atrophy: decrease in size of tissue or organ
from decrease in cells number or size
– Metaplasia: reversible transformation of one
cell type into another
– Dysplasia: abnormal differentiation of dividing
cells
– Anaplasia: cells differentiate to immature form
Lethal Cell Injury
• Physical: heat, cold, radiation, electrothermal
injury, mechanical trauma
• Chemical: alteration of cell metabolism
• Microbial: viral or bacterial invasion of cell
• Ischemic: compromised blood flow to cell
• Immunologic: inflammatory response
• Neoplastic growth: uncontrolled cell growth
• Normal substances: digestive enzymes in
peritoneum; calcification of arteries
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Inflammatory Response
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Reaction to cell injury; neutralizes inflammatory
agent; removes necrotic material & creates
environment for healing & repair to occur
Phases of Inflammatory Response
– Vascular Response
– Cellular Response
• Leukocytosis
• Chemical Mediators
– Formation of Exudate
Vascular Response
• Vasodilation occurs in area of injury
• Results in hyperemia (increased blood flow in
area)
• Raises filtration pressure causing increased
capillary permeability
• Tissue becomes edematous
Cellular Response: Leukocytosis
• Blood flow through capillaries slows r/t fluid loss
• Leukocytes/WBCs (Neutrophils, Monocytes,
Basophils, Eosinophils & Lymphocytes) move to
site of injury via:
– Margination: adhesion to inner capillary wall
– Diapedesis: movement through capillary wall
– Chemotaxis: movement towards site of in
response to WBC-attracting factors
• WBC jobs vary per type: includes phagocytosis,
release of chemical mediators, immune response
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Cellular Response: Chemical Mediators
• Mediators:
– Histamine, serotonin, kinins, prostaglandins,
leukotrienes, complement components,
fibrinopeptides & cytokines
• Actions vary according to mediator & include:
– Vasodilation;increased vascular permeability,
stimulation of contraction of smooth muscle,
stimulation of pain, stimulation of chemotaxis,
histamine release
Formation of Exudate
• Type & quantity depends on tissue & severity
– Serous: thin & watery
– Catarrhal: mucous
– Fibrinous: whitish, filamentous coating;
– Purulent: whitish-yellow & creamy
– Hemorrhagic: bloody
• Beneficial effects of exudate include:
– Impedes microorganism movement; dilutes
toxins; delivers nutrients, antibodies & O2
Healing Process: Regeneration
• Replacement of lost cells with cells of same
type; ability to regenerate depends upon type of
cell:
– Skin, bone marrow, mucous membranes heal
by rapid regeneration
– Liver, pancreas, kidney & bone cells will
regenerate only if organ injured
– CNS & cardiac muscle do not regenerate;
(healing occurs by repair with scar tissue)
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Healing Process: Repair
• Healing as a result of lost cells being replaced
by connective tissue
• Most injuries heal by this way
• More complex process than regeneration
• Occurs by:
– Primary intention
– Secondary intention
– Tertiary intention
Healing by Primary Intention
• Wound margins are neatly approximated
– Initial phase:
• Edges aligned (stapled, sutured etc); incision
fills with blood & clot forms.
• Inflammatory reaction occurs (vascular,
cellular, exudate); fibrin clot forms
– Granulation phase: fibrous scar tissue forms;
pink granulation tissue forms
– Maturation phase/scar contraction: collagen
fibers cause contraction & mature scar forms
Healing by Secondary Intention
• Occurs in wounds with lots of exudate & wide,
irregular margins that can’t be approximated
• Acute inflammatory reaction results in debris,
cells & exudate
• Healing & granulation occurs from edge inward
and from bottom of wound upward until filled
• Results in larger scar
• Prolonged healing
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Healing by Tertiary Intention
• Two layers of granulation tissue are sutured
• Also called “delayed primary intention”because
suturing of wound delayed
– Contaminated wound left open; sutured after
infection controlled
– Sutured wound is infected & is opened to
allow granulation to occur before re-suturing.
• Results in larger, deeper scar than primary or
secondary intention
Local Manifestations of Inflammation
• Redness: hyperemia from vasodilation
• Heat: increased metabolism due to
hyperemia
• Pain: edema, pressure; chemical mediators
• Swelling: edema, exudate & cell migration
• Loss of function: pain & swelling
Systemic Manifestations of Inflammation
• Leukocytosis: WBC increase
• Malaise, nausea, anorexia: probably r/t chemical
mediator release
• Fever & chills: elevated body temp results from
WBC-generated mechanism that results in
shivering, which raises temp until new set point is
reached
• Increased pulse & respirations: r/t increased temp
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Factors Affecting Wound Healing
• Personal hygiene
• Smoking
• Nutrition
• Substance abuse
• Activity/exercise
• Medications
• Circulation
• Stress
• Immunosuppression
• Incontinence
• Age
• Diabetes
• Obesity
• Infection
• Procedures
Infection
• Infection involves invasion of tissues or cells
by microorganisms:
– Bacteria, Viruses, Fungi , Parasites
• Can range from:
– Minor illness (cold, ear infection)
– Life-threatening sepsis
• Inflammation always present with infection
but infection not always present with
inflammation
Normal Resistance to Infection
• Individual: heredity, hygiene, nutrition
• Anatomic: intact skin/mucous membranes
• Mechanical removal of microorganisms:
peristalsis, ciliary action, urine flow, tears
• Chemical factors: pH of secretions
• Local tissue factors: inflammatory response
• WBC function: phagocytosis & stimulus of fever
• Specific acquired defenses: immunity
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Factors Affecting Resistance to Infection
• Breaks in skin & mucous membranes
• Invasive devices
• Stasis of body fluids
• Inadequate nutrition
• Stress
• Immune system dysfunction
• Coexisting medical problems
• Drug therapy
Types of Infections
• Infection: when microorganisms invade body
tissues
• Colonization: microorganisms grow in body
site with no S/Sx of inflammation/infection
• Localized infection confined to one body area
• Systemic infection spreads thru body systems
• Acute infection develops & resolves rapidly
• Chronic infection develops & resolves slowly
• Nosocomial: r/t healthcare delivery
Manifestations of Infection
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Fever: Temperature > 100.4 is indication
Increased pulse & respiratory rate
Inflammatory S/Sx: red, swollen, tender, warm
Pain: dysuria, dyspnea, dysphagia
Purulent drainage: leukocytosis
Enlarged lymph nodes: lymphatic capillaries
dilate with excess fluid, proteins, microbes, etc
• Rash: common with communicable diseases
• Gastrointestinal S/Sx: anorexia, n/v & diarrhea
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