NUR 226G. MCGINTY, MSN, RNInflammation, Fever, Infection
ObjectivesoExplain the pathophysiology of inflammation and feveroOutline basic steps in acute inflammatory responseoExplain role of chemical mediators in the inflammatory responseoOutline general strategies for treating inflammationoCompare and contrast NSAIDSoExplain the role of corticosteroids in the inflammatory response
Review of Body DefensesMechanical Barriers: Defense mechanisms used by the body to protect itself from any injurious agent may be specific or nonspecificNonspecific MechanismsSkin or mucous membrane: often called the first line of defenseSecond line of defense includes processes of phagocytosis and inflammationSpecific MechanismsThird line of defense provides protection: stimulates the production of unique antibodies or sensitized lymphocytes following exposure to specific substances.
InflammationNatural, nonspecific defense mechanismOccurs in response to an injury or antigenInflammation limits spread of injury or antigenContains injuryDestroys microorganismsAcute- 8-10 daysChronic – months or years
Signs/Symptoms of InflammationSwellingPainWarmthRedness
InflammationThe general signs and symptoms of inflammation serve as a warring of a problem, which may be hidden within the bodyInflammation is not the same as infectionInfection: microorganisms such as bacteria, viruses, or fungi are always present at the site causing the inflammation.
Chemical MediatorsAlert surrounding tissue of injuryHistamineSerotoninLeukotrienesBradykininComplementProstaglandinsInterstitial fluid and bloodCytokines serve as communicators in the tissue fluids, sending messages to lymphocytes and macrophages, the immune system or the hypothalamus to induce fever.
Chemical MediatorsMany of these chemicals also intensify the effects of other chemicals in the responseMany anti-inflammatory drugs and antihistamines reduce the effects of some of these chemical mediators
HistamineThe key chemical mediator of inflammationReleased from mast cellsLocated in skin, bronchial tree, GI tract, along blood vesselsCan initiate inflammatory response w/in secondsCauses dilation of vessels, increased permeability, Itching, Smooth-muscle constrictionAlso responsible for anaphylaxis
Histamine ReceptorsHistamine can produce its effects by interacting with two different receptorsH1receptors: found in vascular smooth muscle, in bronchi, and on sensory nervesStimulation results in itching, pain, edema, vasodilation, bronchoconstrictionCharacteristic of inflammation and allergyH2receptors located in stomachStimulation results in secretion of hydrochloric acid
LeukotrienesReleased from mast cellsSimilar effects to those of histamines
BradykininPresent in mast cells and in plasmaVasodilates and causes painEffects similar to histamineBroken down by angiotensin converting enzyme