Chapter 5 Inflammation and Healing

Replacement by connective tissue

(scar or fibrous tissue formation) takes place with extensive tissue damage or when cells are incapable of mitosis (brain, myocardium). Chronic inflammation or infection results in more fibrous material.

large or deep area of tissue

A blank damage requires a prolonged healing time and results in larger scars.

Small gap(injury)

A blank in the tissue will completely heal within a short period of time.

Leukocytosis

Abnormally high WBC count The normal number of WBCs in the blood is 4,500 to 11,000 WBCs per microliter

Factors that may delay healing

Advanced age, reduced mitotic potential Poor nutrition and dehydration Anemia Circulatory problems Presence of other disorders or chronic diseases Irritation, bleeding, or excessive mobility Infection, foreign material Exposure to radiation Chemotherapy Prolonged use of glucocorticoids

acute inflammation and release of chemical mediators, resulting in a major fluid shift, edema, and decreased blood volume.

All burns cause what?

Aspirin

Although blank is the oldest anti-inflammatory agent on the market, other drugs that mimic the effects of corticosteroids are now available as well. These drugs are not chemically related to corticosteroids and are therefore referred to as nonsteroidal anti-inflammatory drugs (NSAIDs).

outside edges inward

At the same time as blood clot formation, nearby epithelial cells undergo mitosis, extending the wound from the blank: Fibroblasts and connective tissue cells enter the area and produce collagen. Fibroblast and macrophages also produce cytokines (growth factors): Stimulation of epithelial cell proliferation and migration Development of new blood vessels (angiogenesis) in healing tissue

Decreased high

At the venous end of the capillary, the hydrostatic pressure is blank and the osmotic pressure is relatively blank. Both the blank hydrostatic pressure and the blank osmotic pressure in the capillaries promote the diffusion of fluid, carbon dioxide, and wastes into the blood.

Cold

Blank applications are useful in the early stage of acute inflammation. These applications cause local vasoconstriction, decreasing edema and pain.

Local Inflammation Signs

Blank are characterized by redness, heat, swelling, and pain: Redness and warmth are caused by increased blood flow to the injured area (example of cellulitis). Edema (swelling) is caused by the shift of protein and fluid into the interstitial space. Pain is a result of increased pressure by the fluid on nerve endings as well as local irritation by bradykinin. Loss of function may develop if cells lack nutrients or if swelling interferes with function.

Burns

Blank are classified according to the depth of skin damage and the percentage of the body surface involved.

Hypertrophic scar tissue

Blank is an overgrowth of fibrous tissue consisting of excessive collagen deposit. Masses are disfiguring and often cause more severe contractures.

Systemic effects

Blank or general manifestations include mild fever, malaise, fatigue, headache, and anorexia.

Microbial toxins

Blank released into the bloodstream can also act as pyrogens.

Ulceration

Blank results when the blood supply is impaired around a scar, resulting in further tissue breakdown. Can occur at a future time.

Capillaries

Blood cells and plasma proteins remain in the

isoenzymes

Blood levels of blank and other cell enzymes may be elevated in the presence of severe inflammation and necrosis: Some of these enzymes are tissue-specific and may be helpful in locating the site of the necrotic cells. Other enzymes are not tissue-specific and can be elevated as a result of an inflammation in a nondisclosed area.

NSAIDs

Can be categorized into seven groups: Salicylates (e.g., aspirin) Para-chlorobenzoic acid derivatives, or indoles (e.g., indomethacin—Indocin) Phenylacetic acids (e.g., diclofenac sodium—Voltaren) Propionic acid derivatives (e.g., ibuprofen) Fenamates (e.g., meclofenamate sodium monohydrate—Meclomen) Oxicams (e.g., piroxicam—Felden) Selective COX-2 inhibitors; second-generation NSAIDs (e.g., celecoxib—Celebrex)

Contractures and obstructions

Complication of scarring Scar tissue is nonelastic and most often will shrink over time. This shrinkage may restrict the range of movement of a joint and eventually may result in contracture. Fibrous tissue may limit movement of the mouth or eyelids. Shrinkage of the scar tissue may also cause shortening or stenosis (narrowing) of structures (for example, narrowed esophagus causing obstruction during swallowing)

Loss of function

Complication of scarring a result of the loss of normal cells and lack of specialized structures or normal organization in scar tissue—that is, scar tissue that replaces normal skin will lack hair follicles, glands, and sensory nerve endings. In a highly organized organ, scar tissue will not fit the normal patterns of blood vessels, tubules, and/or ducts. The replacement tissue therefore will not provide normal function.

Adhesion

Complication of scarring are bands of scar tissue joining two surfaces that are normally separated, for example, adhesions between loops of intestine or between the pleural membranes—usually a result from inflammation of infection in the body cavities. Prevent normal movement of structures and may cause distortion or twisting of the tissue.

Beneficial anti-inflammatory effects of glucocorticoids

Decreasing capillary permeability and enhancing the effectiveness of epinephrine and norepinephrine—vascular system stabilized Reduction in the number of leukocytes and mast cells, decreasing the release of histamine and prostaglandins Blocking the immune response—a common cause of inflammation

Inflammation

Diagnostic tests for blank primarily involve testing changes in the blood that occur as a result of it. These changes include: Leukocytosis Elevated serum C-reactive protein Elevated erythrocyte sedimentation rate or ESR Increased plasma proteins and cell enzymes in serum:

size of the injury

Factors affecting the healing process are greatly determined by the blank. Several factors play a role in the healing process or in the delay thereof.

Elevated Serum C- reactive protein

For a standard CRP test, a normal reading is less than 10 milligram per liter (mg/L). A test result showing a CRP level greater than 10 mg/L is a sign of serious infection, trauma or chronic disease

Scar

Gradually a tight, strong blank is formed and the capillaries in the area decrease; the color of the scar slowly fades. Scar tissue is not normal, functional tissue and does not contain any specialized structures such as hair follicles or glands.

regeneration or by scar formation.

Healing of tissue damage either happens by blank or blank

Hot or cold use depends on situation

Heat and moderate activity may improve circulation in the affected area, removing excess fluid, pain-causing chemical mediators, and waist metabolites. The application may also promote healing.

prevent microbes from entering the underlying tissues.

If the inflammatory response begins as soon as the skin is broken, it may be strong enough to

mast cells and platelets

In addition to bradykinin and histamine, blank and blank release chemical mediators including serotonin, prostaglandins, and leukotrienes. Some of these chemical mediators are responsible for the later effects, prolonging the inflammation. Many of these chemicals also intensify the effects of other chemicals in the response. Many anti-inflammatory drugs and antihistamines reduce the effects of some of these chemical mediators.

Eosinophil

Increased numbers in the blank count usually indicate an allergic reaction or a parasitic infection.

ASA

Individuals may be allergic to Blank and similar anti-inflammatory drugs. These drugs may also cause irritation and ulcers in the stomach.

Potential Complications of Inflammation

Infection develops when microorganisms penetrate the inflamed tissue. Inflammatory exudate provides an excellent medium for microorganisms to reproduce and colonize. Ulcers (often deep) result from severe or prolonged inflammation. Cell necrosis and lack of cell regeneration cause the erosion of tissue; this can lead to complications such as perforation of viscera or development of extensive scar tissue. Skeletal muscle spasms may be initiated by inflammation. This may result in: Sprains Tendonitis Fractures Local complications depend on the site of inflammation.

Second Line of Defense

Is nonspecific Involves the process of phagocytosis and inflammation Includes inflammation and interferons

First Line of Defense

Is nonspecific Is a mechanical or chemical barrier Includes the skin and mucous membranes that block bacteria and harmful substances from entering the body Body secretions like tears or saliva

Third Line of Defense

Is specific Involves lymphocytes that produce specific antibodies against a specific invader

Characteristics of chronic inflammation

Less swelling and exudate than in acute inflammation. More lymphocytes, macrophages, and fibroblasts than in acute inflammation Tissue destruction (common) Extensive scar tissue formation Granuloma(s) that may develop around a foreign object

Major Burns

Medical Emergency

Hydrostatic Pressure

Movement of fluid, electrolytes, oxygen, and nutrients out of the capillary at the arteriolar end is due to the net blank. The relative osmotic pressures in the blood and interstitial fluid also provide a concentration gradient and therefore aid in the diffusion of substances.

Normal

Once the pathogens are eliminated, the set point for body temperature returns to blank, causing perspiration to cool off the body.

Physiotherapy Occupational therapy Splints, which may be required during acute episodes

Other treatment measures may be necessary to maintain joint mobility and reduce pain:

Histamines

Released by mast cell granules Immediate vasodilation and increased capillary permeability to form exudate

Prostaglandins(PGs)

Released synthesis from arachidonic acid in mast cells Vasodilation, increased capillary permeability, pain, fever, potentiate histamine effect

Leokotrines

Released through synthesis from arachidonic acid in mast cells Later response; vasodilation and increased capillary permeability, chemotaxis

type, intensity, and duration of the tissue injury.

The course of the inflammatory response and the healing process are dependent on the blank

Neutrophils

The first cells at the site of injury are blank, followed by monocytes and macrophages.

Diapedesis

The movement of neutrophils, monocytes, and macrophages out of the capillaries into the interstitial space is referred to as

elevated erythrocyte sedimentation rate

The normal range is 0 to 22 mm/hr for men and 0 to 29 mm/hr for women.

Increased Plasma Protein and Cell Enzymes in serum

The normal serum protein level is 6 to 8 g/dl. Most of them are products of the liver. Their synthesis is increased during the primary stages of inflammation. The proteins are either pro- or anti-inflammatory and are referred to as acute phase reactants.

blood clot forms

The process of tissue repair begins following injury when a blank and seals the area: Inflammation develops in the surrounding area. Foreign material and cell debris will be removed by phagocytes, monocytes, and macrophages. Granulation tissue grows into the gap from nearby connective tissue: Granulation tissue is highly vascular and appears pink or red in color. It contains many capillary buds from surrounding tissue. This tissue is fragile and can easily be broken by microorganisms or stress on the tissue.

With brief exposure to a damaging agent

The response often subsides after approximately 48 hours. Vascular integrity is regained. Excess fluid and proteins are recovered by the lymphatic capillaries and returned to the cardiovascular system. The signs and symptoms of inflammation gradually decrease.

capillary beds

Under normal conditions, not all blank are open at the same time unless the metabolic needs of cells in a particular area are not met by the blood supply or metabolic byproducts have to be removed.

Atrophy of lymphoid tissue and reduced numbers of white blood cells, increasing the risk of infection and a decrease in the immune response Catabolic effects including osteoporosis, muscle wasting, and tendency to thinning and breakdown of skin and mucosa Delayed healing Delayed growth in children Retention of sodium and water

What are the side effects of glucocorticoids?

The inflammatory process

When capillaries and tissue cells are injured, these cells release bradykinin. Bradykinin stimulates pain receptors. The sensation of pain activates mast cells and basophils to release histamine. Nerve reflexes at the site of injury cause immediate but transient vasoconstriction, but the rapid release of chemical mediators causes vasodilation, which causes hyperemia, an increased blood flow to the area. Both bradykinin and histamine not only cause vasodilation in the injured area, but also increase the capillary permeability. The increase in permeability allows plasma proteins to move into the interstitial space. Attracted by chemotaxis, leukocytes move to the site of injury.

They have thinner skin

Why does burns affect the elderly different than younger adults?

Short period of Time

With resolution, damaged cells recover and the tissue returns to normal within a blank (for example, as with sunburn).

Factors that promote healing

Youth/age Nutrition: protein, vitamins A and C Adequate hemoglobin levels Effective circulation Clean, undisturbed wound No infection or trauma to the injured site

Abscess

a localized pocket of purulent exudate in a solid tissue.

Bradykinin

a powerful vasodilator that increases capillary permeability and constricts smooth muscle

Glucocorticoids

also referred to as corticosteroids or steroidal anti-inflammatory drugs, are valuable in the short-term treatment of many disorders, but they do have significant side effects.

Scars

are areas of fibrous connective tissue that replace the injured tissue after injury or disease. blank formation is part of the healing process, and every wound except for very minor lesions results in some degree of scarring. blank tissue is structurally and functionally different than the tissue it replaces.

Differential White Blood Cell Counts

are helpful in distinguishing a viral from a bacterial infection. Neutrophils - 2500-8000 per mm3 (55-70%) Lymphocytes - 1000-4000 per mm3 (20-40%) Monocytes - 100-700 per mm3 (2-8%)

Monocytes

blank that leave the bloodstream mature into macrophages and quickly phagocytize microbes or other debris.

The body's nonspecific response

blank to tissue injury, resulting in redness, swelling, warmth and pain, and sometimes loss of function, is inflammation.

Chronic Inflammation

can occur after an unsuccessful acute inflammation. Bacteria or foreign objects persist in a traumatic wound. Pus formation and/or discharge, suppuration, and incomplete wound healing may be characteristic.can also occur as a distinct process without much previous inflammation, such as in the case of: Microbes that are insensitive to phagocytosis and are relatively resistant to clearance in an acute inflammatory response Microorganisms that can survive in macrophages Microorganisms that produce toxins that stimulate tissue-damaging reactions Chemicals, particulate matter, or physical irritants can also cause an inflammation that lasts longer than 2 weeks.

Chronic Inflammation

can spread slowly and may result in serious metabolic dysfunctions and long-term health issues. It has been suggested that chronic inflammation may be a major contributing factor to chronic degenerative diseases. Chronic inflammation is almost always accompanied by tissue destruction.

Serous Exudate

consists primarily of fluid with small amounts of protein and white blood cells (e.g., allergic reactions, burns).

Regeneration

damaged tissue is replaced by identical tissue from the proliferation of nearby cells. This type of healing may be limited if the organization of a complex tissue is altered; that is, fibrous tissue may develop, distorting the orderly arrangement in an organ (such as in the liver).

Severity of Burns

depends on the cause of the burn, the temperature, duration of contact, and the extent of the burned surface, as well as the site of injury. Skin thickness also varies in the different areas of the body, thus influencing the severity.

The amount of necrosis

depends on the cause of the trauma, not the factors contributing to the inflammatory response.

Pyrogens

fever-producing substances, are released by white blood cells and macrophages in response to a microbial invasion. Stimulate the specific neurons in the hypothalamus that release prostaglandins.

The inflammatory process

follows basically the same pathway regardless of cause. may develop immediately and last a short time, it may have a delayed onset (for example, with sunburn), or it may be severe and prolonged. The severity is dependent on the specific cause and duration of exposure.

Anti-inflammatory agents such as aspirin (acetylsalicylic acid, ASA)

inhibit the biosynthesis of prostaglandins at the site of inflammation, thus reducing the inflammatory response. reduce pain, reduce elevated body temperature, and inhibit platelet aggregation.

The inflammatory response

is a protective mechanism and an important basic concept in pathophysiology. The response is intended to localize and remove any injurious agent. The general signs and symptoms of inflammation are a warning of a problem.

Body temperature

is regulated by the hypothalamus.

Excess Tissue Fluid

is returned to the cardiovascular system by lymphatic vessels.

Fibrinous Exudate

is thick and sticky with high cell and fibrin count. This type of exudate represents an increased risk of scar formation.

Purulent Exudate

is thick, yellow-green in color, and contains more leukocytes, cell debris, and microorganisms. This type is referred to as pus and is indicative of a bacterial infection.

High fever

may be beneficial if it impairs the growth and reproduction of an organism

Burns

may be mild or cover only a small area of the body, or they may be severe and life-threatening. may be caused by direct contact with a heat source, or by chemicals, radiation, or electric shock. In addition to cutaneous injury, they are also associated with smoke inhalation injuries.

Hemorrhagic Exudate

may be present if a number of blood vessels have been damaged.

Excessive necrosis

may lead to ulcer formation or tissue erosion.

Chemotaxis

movement by a cell or organism in reaction to a chemical stimulus

Granulation tissue

new tissue that is pink/red in color and composed of fibroblasts and small blood vessels that fill an open wound when it starts to heal

Interferons

nonspecific agents that protect uninfected cells against viruses

Persistent inflammation

occurs until the causative agent is removed.

Healing by first intention

occurs when the wound is clean, free of foreign material and necrotic tissue, and the edges are close together with a minimal gap. This type of healing is usually seen with surgical incisions.

Elevation

of the inflamed limb is used to improve fluid flow away from the damaged tissue.

Pyrexia

often occurs when the inflammation is extensive. The fever may become severe, depending on the particular microorganism involved.

Neutrophils

phagocytize bacteria and destroy them via their hydrolytic enzymes of the lysosomes.

Prostaglandins

raise the physiologic set point of the body temperature. This results in shivering and an increase in body temperature.

Exudate

refers to a collection of interstitial fluid formed in the inflamed area. The different types of exudate vary with the cause of the trauma

Kinins(bradykinin)

released from activation of plasma protein(kinogen) Vasodilation and increased capillary permeability, pain, chemotaxis

RICE

rest, ice, compression, elevation

Acetulsalicylic Acid

should not be used in children with viral infections because the combination may cause Reye's syndrome.

Healing by second intention

takes place with a large break in tissue, more inflammation, a longer healing period, and formation of more scar tissue (for example, as with a compound fracture).

Phagocytosis

the process by which neutrophils(leukocyte) and macrophages randomly engulf and destroy bacteria, cell debris, and foreign matter

Mild to Moderate exercise

useful in cases of many inflammatory conditions. Improved blood and fluid flow is beneficial and could improve mobility.

Compression

using elastic stockings or other supports also may reduce fluid accumulation.