Chapter 29: Infection Prevention and Control Flashcards
Infection:
Invasion of a susceptible host (human being)
Pathogens:
microorganisms that lead to disease
Colonization:
presence and growth of microorganisms within a host but without tissue invasion or damage
Disease or infection results only
if the pathogens multiply and alter normal tissue function.
Some infectious diseases such as viral meningitis and pneumonia have a
low or no risk for transmission even though they are serious for patients, they do not pose a risk to others
Communicable disease:
if an infectious disease can be transmitted directly from one person to another
If pathogens multiple and cause clinical signs and symptoms, the infection is:
symptomatic
If clinical signs and symptoms are not present, the illness is termed
asymptomatic
Infection occurs in a cycle that depends on the presence of which elements (6)
infectious agent or pathogen
reservoir or source for pathogen growth
port of exit from reservoir
mode of transmission
port of entry to a host
susceptible host
Infection can develop if this chain remains uninterrupted
Virulence (3)
ability of microorganisms to produce disease
ability to enter and survive in a host
susceptibility of host
Most effective way to break chain of infection
HAND HYGIENE
Reservoir is a
place where microorganisms survive, multiple, and await transfer to a susceptible host
Common reservoirs:
humans
animals
insects
food
water
organic matter on inanimate surfaces
Human reservoirs are divided into 2 categories:
Acute/symptomatic
Those who show no signs of diseases but are carriers!
Aerobic organisms can cause:
more infections in humans than anaerobic organisms
Ideal temperature for most human pathogens:
Ideal pH for microorganisms:
68-109 F
5.0-7.0
Portals of exit include:
Blood
Skin
Mucous membranes
Respiratory tract
Genitourinary tract (GU)
Gastrointestinal tract (GI)
Transplacental (mother to fetus)
Major route of transmission for pathogens identified in the health care setting:
unwashed hands of healthcare worker!!!
Modes of transmission (6)
Direct
- person to person (fecal, oral) physical contact between source and host)
Indirect
- personal contact of host with contaminated inanimate object (needles, dressings, environment)
Droplet
- large particles that travel up to 3 feet during coughing, sneezing, talking and come in contact with susceptible host
Airborne
- Droplet nuclei, residue or evaporated droplets suspended in air during coughing or sneezing or carried on dust particles
Vehicles
- contaminated items
- water
- drugs, solutions
- blood
- food
Vector
- external mechanical transfer (flies)
- mosquitos, louse, flea, tick
Course of infection by stage: (4)
Incubation period
Prodromal stage
Illness stage
Convalescence
Incubation period:
interval between entrance of pathogen into body and appearance of first symptoms
chickenpox 14-16 days after exposure
Common cold 1-2 days
influenza 1-4 days
Suprainfection:
Develops when broad-spectrum antibiotics eliminate a wide range of normal flora organisms, not just those causing infection
When normal bacterial floras are eliminated, body defenses are reduced
Serous fluid
clear, like plasma
Sanguineous fluid
containing red blood cells
Purulent fluid
containing WBCs and bacteria
Major sites for HAIs (health care associated infections (4)
surgical or traumatic wounds
urinary tract
respiratory tract
bloodstream
Natural defense mechanisms against infection (7)
Skin
Mouth
Eye
Respiratory tract
Urinary tract
Gastrointestinal tract
Vagina
HAI infections are either:
exogenous
endogenous
Exogenous infection comes from
microorganisms found outside the individual
Endogenous infection occurs when part of the
patient’s flora becomes altered and an overgrowth results (staph, yeasts)
Iatrogenic infections are
a type of HAI caused by an invasive diagnostic or therapeutic procedure
Factors influencing infection prevention control
age
nutritional status
stress
disease process
A reduction in the intake of protein and other nutrients such as carbs and fats
reduces body defenses against infection and impairs wound healing
Risk factors of infection in adults (8)
Chronic disease
Lifestyle- high-risk behaviors
Occupation
Diagnostic procedures
Heredity
Travel history
Trauma
Nutrition
Examples of nursing diagnoses in the making:
risk for infection
imbalanced nutrition: less than body requirements
impaired oral mucous membrane
risk for impaired skin integrity
social isolation
impaired tissue integrity
Examples of common goals:
Preventing further exposure to infectious organisms
Controlling or reducing the extent of infection
Maintaining resistance to infection
Verbalizing understanding of infection prevention and control techniques (hand hygiene)
Medical asepsis:
absence of pathogenic (disease producing) microorganisms.
Aseptic technique refers
to practices that reduce risk for infection
2 types of aseptic techniques
Medical
Surgical
Basic medical aseptic techniques
break the chain of infection
Use this technique for all patients, even when no infection is diagnosed
Medical asepsis:
aggressive preventive measures such as
hand hygiene
barrier techniques
routine environmental cleaning
Disinfection
process that eliminates many or all microorganisms, with the exception of bacterial spores from inanimate objects
2 types of disinfection:
disinfection of surfaces
high-level disinfection
-required for some patient care items such as endoscopes and bronchoscopes
Sterilization and methods
eliminates or destroys all forms of microbial life, including spores
methods include: steam, dry heat, hydrogen peroxide plasma, ethylene oxide
Factors that influence the efficacy of the disinfecting or sterilizing method (6)
concentration of solution and duration of contact
type and number of pathogens
surface areas to treat
temperature of environment
presence of soap
presence of organic materials
Critical items for sterilization (4)
Items that enter sterile tissue or the vascular system…Must be free of EVERYTHING!!
Surgical instruments
Cardiac or intravascular catheters
urinary catheters
implants
Semicritical items for sterilization (5)
Items that come in contact with mucous membranes or non intact skin. These items must be free of all microorganisms (except bacterial spores), must be high leveled disinfected or sterilized
Respiratory and anesthesia equipment
endoscopes
endotracheal tubes
GI endoscopes
Diaphragm fitting rings
Noncritical items:
Items that come in contact with intact skin but not mucous membranes. Must be disinfected
Bedpans
Bloodpressure cuffs
Bedrails
Linens
Stethoscopes
Bedside trays and patient furniture
Food utensils
Order of putting ON PPE
Gown
Mask
Goggles
Gloves
Order of taking OFF PPE
Gloves
Goggles
Gown
Mask
Infection prevention and control to reduce reservoirs of infection(8)
Bathing
Dressing changes
Contaminated articles
Contaminated sharps
Bedside unit
Bottled solutions
Surgical wounds
Drainage bottles and bags
Contact precautions:
Used for DIRECT and INDIRECT contact
Care and handling of contaminated body fluids (blood)
Gown and gloves used
Droplet precautions:
Focuses on diseases that are transmitted by large droplets (greater than 5 microns) expelled into the air and by being within 3 FEET OF PATIENT
Mask needed
Influenza
Airborne precautions
focuses on diseases transmitted by smaller droplets that remain in air for long time
specifically equipped room with a negative air flow (airborne infection isolation room)
air is not returned to the inside ventilation system but is FILTERED through a high-efficiency particulate air (HEPA) filter and exhausted directly OUTSIDE
wear an N95 respirator every time they enter room
Protective environment:
Very limited patient population
specialized room with POSITIVE airflow
Airflow rate is set at GREATER than 12 air exchanges per hour and all air is filtered through a HEPA filter.
Masks!
