NUR 1106 Final Exam Preparatory Notes

Chapter 24: asepsis and infection control
 Infection cycle:




o Infectious agent:
 Bacteria are the most significant and most commonly observed infection-
causing agents in health care institutions
 Virus: smallest microorganisms, visible only with an electron microscope
 Common cold, hepatitis B and C, and AIDS
 Antibiotics have no effect; there are some antiviral medications
 Fungi: plant-like organisms (mold and yeasts) that are present in the air,
soil, and water
 Athlete’s foot, ringworm, yeast infections
 Parasites: organisms that live on or in a host and rely on it for
nourishment
 Malaria
 An organism’s potential to produce disease in a person depends on:
 Number of organisms
 Virulence of the organisms, or its ability to cause disease
 Competence of the person’s immune system
 Length and intimacy of the contact between the person and the
microorganism
 Colonization: infection is present once the person exhibits specific
manifestations of the disease

,  E. coli and C. difficile
o Reservoir: natural habitat of the organism
 Ex: other people, animals, soil, food, water, milk, and inanimate objects
o Portal of Exit: point of escape for the organism from the reservoir.
 in humans, common portals of exit include the respiratory, GI, and
genitourinary tracts, as well as breaks in the skin and blood and tissue
o Means of Transmission:
 Direct contact: requires close proximity between the susceptible host and
an infected person or a carrier, including kissing and sexual intercourse
 Indirect contact: involves personal contact with either a vector (living
creature that transmits an infectious agent to a human, usually an insect),
or a fomite (inanimate object, such as equipment or countertops)
 Droplet transmission: greater than 5 mcm
 Airborne: particles are less than 5 mcm
o Portal of Entry: point at which organisms enter a new host
 Skin and urinary, respiratory, and GI tracts are common portals of entry
o Susceptible Host: source that provides shelter and nourishment to a
microorganism once the microorganism has overcome any resistance mounted
by the host’s defenses.
 Susceptibility: degree of resistance the potential host has to the
pathogen.

TABLE 24-1 Organisms Capable of Causing Disease
ORGANISM RESERVOIR MEANS OF DISEASE TRANSMITTED
TRANSMISSIO
N

B Borrelia burgdorferi T Ticks (sheep, cattle, deer, C contact (indirect- L Lyme disease
mice) vectors)

E Escherichia coli (E. coli) F feces C contact E. E. coli infection (Most common
C contaminated food or water (direct/indirect) manifestation is diarrhea)

H Hepatitis B virus (HBV) B blood C contact (direct; H Hepatitis B
F feces indirect possible,
Body fluids and excretions but unlikely)

H Human immunodeficiency B blood C contact (direct) A Acquired immunodeficiency
virus (HIV) S semen syndrome (AIDS)
V vaginal secretions
B breast milk

Mycobacterium S Sputum (respiratory tract) C contact (airborne) T Tuberculosis
tuberculosis (M.
tuberculosis [TB])

, S Salmonella I Intestinal tracts of humans C contact D Diarrheal illness
and other animals, including (direct/indirect)
birds

Staphylococcus aureus S Skin surface C Contact • Minor skin infections: Carbuncle,
Mouth (direct/indirect) boil, pimple, abscess
N Nose • Respiratory infection
T Throat • Endocarditis (infection of the hea
valves)
• Osteomyelitis (bone infection)
• Bacteremia (bloodstream infectio



 Stages of Infection:
o Incubation period: The incubation period is the interval between the pathogen’s
invasion of the body and the appearance of symptoms of infection. During this
stage, the organisms are growing and multiplying.
o Prodromal stage: A person is most infectious during the prodromal stage. Early
signs and symptoms of disease are present, but these are often vague and
nonspecific, ranging from fatigue and malaise to a low-grade fever. This period
lasts from several hours to several days.
o Full (acute) stage of illness: The presence of infection-specific signs and
symptoms indicates the full stage of illness. The type of infection determines the
length of the illness and the severity of the manifestations.
o Convalescent period: involves the recovery from the infection. Convalescence
may vary according to the severity of the infection and the patient’s general
condition. The signs and symptoms disappear, and the person returns to a
healthy state. However, depending on the type of infection, there may be a
temporary or permanent change in the patient’s previous health state even after
the convalescent period.

 Using PPE: REVIEW SKILL 24-2 USING PPE
o Gloves:
 When nursing care activities don’t involve the possibility of soiling the
hands with body fluids, gloves are not necessary. Activities such as
turning a patient, feeding a patient, taking vital signs, and changing IV
fluid bags do not require the use of gloves as long as the potential contact
with body fluids is not present
 Reactions to latex fall into three categories: (1) irritant contact dermatitis
that results from contact with gloves where the hands become irritated
and dry—this is not actually not an allergy at all; (2) allergic contact
dermatitis (a type IV sensitivity), which is an actual reaction to the latex
that results in localized pruritus (itching), erythema (redness or rash), and
urticarial lesions 24 to 96 hours after the contact; and (3) a true latex