immune system Flashcards
What is
Immunity?
When a person has protection against a disease or condition
Person will not get or be affected by the disease
Immune System
Protects body against disease and infection
Does so by working both inside and outside body
Works to STOP attackers from getting into body and to REACT and DEFEND if attackers get in
3 Outcomes of Exposure to
a Pathogen
- Immune system destroys pathogen
- Immune system does not destroy pathogen, no infection develops
- An infection develops sometime after exposure to pathogen
2 types of immunity
non-specific:
body’s reaction to anything it sees as foreign which enters body
specific:
body’s reaction to a specific foreign agent
first line of defense for Non-Specific Immunity
mechanical & physical barriers
(intact skin, mucous membranes)
Chemical barriers
(tears, perspiration)
Reflexes
(cough, sneeze, diarrhea)
second line of defense for Non-Specific Immunity
inflammation:
release of histamine to injured area, causing blood vessels to dilate and bring blood to area
Phagocytosis:
white blood cells digest and destroy microorganisms or unwanted substances
Fever:
stimulates phagocytosis and decreases ability of certain pathogens to multiply
Phagocytes
some types of WBCs are able to surround microorganisms
and cellular debris and digest them
process is called phagocytosis
Fever
Temp elevated above normal
Rate and depth of respirations increases (tachypnea)
Heart rate increases (tachycardia)
Fever helps to defend against invading organisms/infection
stimulates phagocytosis
makes the internal environment too hot for some pathogens to multiply
causes and danger of fever
infection
inflammatory stimulus
some drugs
environment (heat stroke)
dehydration
dangers:
temp above 40oC may cause seizures
temp above 41oC may cause damage to the temp center in hypothalamus
inability to decrease temp
Fever in older adults
temperature may be normal even if infection present
Watch for:
new or increased confusion or delirium
new or increased incontinence
loss of appetite
decreased ability to perform ADLs
Falls
change in mood
Care Giving Actions for a
Client with Fever
no cooling measures unless temp is dangerously high
warm blanket, or light sheet
cool washcloth
increase fluid intake
rest
comfortable room temp
antipyretics (delegated)
S & S of Inflammation
redness & heat:
increased blood supply to the area from dilated blood vessels
tissue swelling:
fluid leaking from blood vessels from increase permeability
pain:
tissues stretched or compressed from swelling
may cause lack of mobility at site
Treating Inflammation
elevate the injured area:
decrease further accumulation of fluid
application of cold:
constrict vessels, slow swelling
decrease pain
application of heat:
not til a few days after injury
promote blood flow to area (dilate vessels)
brings O2 and nutrients to area
helps remove wastes
medications
Specific Immunity
final line of defence
immune system activated when antigen sensed
increased production of lymphocytes
produce antibodies to destroy antigen
increased production of phagocytes
digest antigen
if same antigen enters the body
at later time, it will be recognized
antibodies
proteins produced by B lymphocytes
recognize, attack, and destroy specific antigens
antigens
abnormal or unwanted substances in the body, e.g. pathogens
lymphocytes
WBCs which produce antibodies
B cells & T cells are types of lymphocytes
Types of Lymphocytes
B lymphocytes (B-cells):
Cells cause production of antibodies
T lymphocytes (T-cells):
Cells destroy invading cells
acquired Immunity
naturally:
active, get the disease ex. chicken pox
passive, mom to babe via placenta and breast milk (only lasts about 6 mos)
artificially:
active, vaccine causes body to produce antibodies
immune globulin, antibodies from someone else
Factors Which Weaken the
Immune System
aging, elderly
poor nutrition
stress or anxiety
lack of sleep
poor general health
environmental or other toxins
diseases such as AIDS
immunosuppressant meds
side effects (se) of some other meds
infant who is not breast fed
Autoimmune
Disorders
immune system can’t tell difference between self and non-self
body produces immune response to self, attacks self
Treatment…
immunosuppressants
tx for s&s, e.g. anti-inflammatories, analgesics
Effects of Aging on the
Immune System
Fewer and less responsive T cells
B cells do not create antibodies as fast
number of antibodies produced compared to antigen is decreased (increase risk for pneumonia and
flu)
Cancerous tumor cells are not identified and eliminated as quickly
Killer cells are less able to distinguish the self from the non-
self
HCA Interventions when
working with Older Adults
and People with Weak
Immune Systems
Medical Asepsis!!
Promote healthy diet
Promote regular routines and
sleep
Decrease stress
