Chapter 29 -Infection Prevention and Control
Types of infections, how they are transmitted, prevention of infection
Colonization: microorganism invades host without tissue
invasion/damage/disease
Infection: invasion of susceptible host by pathogens or microorganisms resulting
in signs/symptoms
LOCAL: limited to a body part
SYSTEMIC: spreads/damages other body parts
ACUTE: sudden onset/ short duration
CHRONIC: slow onset/ long duration (months to years)
NOSOCOMIAL: hospital acquired infection
HAI: from any healthcare setting
IATROGENIC: type of HAI from a procedure
exogenous: from germs outside the patient
endogenous: patient’s flora balance changes and causes
overgrowth
Standard precautions and transmission based precautions, when to use which?
Standard Precautions are designed for all clients. Apply to: blood, all body
fluid, excretions, secretions (except sweat). Also for nonintact skin, mucous
membranes. This will decrease risk of transmitting recognized and unrecognized
sources.
Transmission based precautions are used in addition with standard precautions:
for known or suspected infections that are spread in one of three ways: Airborne,
Droplet, Contact. This may be used alone or in combination, but always in
addition to standard precautions.
AIRBORNE <5 Chickenpox (VZ), measles, TB Private negative pressure room, HEPA
micron filter, N95 mask or respirator
(tiny particles
suspended in air)
DROPLET >5 micron Strep throat, Influenza, Private room, mask
(large particles within pneumonia, scarlet fever
3-6ft)
CONTACT Cdiff, norovirus, VRE, MRSA, Private room, gloves, gown
VZ, wound infections
Airborne Precautions (droplet nuclei smaller than 5 microns) ex: measles,
chickenpox, disseminated varicella zoster, pulmonary or laryngeal tuberculosis
Protection private room with negative pressure airflow at least 6-12
exchanges/hr. Mask or respiratory protection device, N95 respirator.
, Droplet Precautions ( droplets larger than 5 microns; being within 3 ft of pt. ex)
Diphtheria, rubella, streptococcal pharyngitis,pneumonia or scarlet fever in
infants and young children, pertussis, mumps, Mycoplasma pneumonia,
meningococcal pneumonia or sepsis, pneumonic plague Protection Private room
or cohort patients, mask or respirator required
Contact Precautions (direct patient or environmental contact) colonization or
infection with MRSA, VRE, C.diff, Shigella. Major wound infections such as
herpes simplex, scabies, varicella zoster, respiratory syncytial virus. Protection
private room or cohort patients gloves and gowns worn.
Protective Environment Allogeneic hematopoietic stem cell transplants.
Protection private room, positive airflow with 12 or more gas exchanges/ hr.
Hand hygiene
1-before touching patient
2-after touching patient/environment
3-after taking off gloves
4-before procedure
5-hands are visibly soiled
-important in breaking chain of infection (method of transmission-direct or indirect
contact)
-alcohol based is better UNLESS hands visibly soiled OR C-Diff present
-instruct patients and support persons about hand hygiene (before handling food,
eating,
after eliminating, after touching infectious material)
-wear gloves when handling secretions and excretions
Chain of infection, breaking the chain of infection
Agent → Number/ Virulence/ Ability to enter or live.
Prevent by disinfecting/sterilizing
Reservoir → Carriers can be people, animals, etc
Prevent by good hygiene, avoid prolonged moisture
Portal of Exit → way out of carrier
Prevent by cough etiquette, mind your sterile field
Mode of transportation →
INDIRECT: Vehicle (contaminated object) or Vector (flies,
mosquitos)
DIRECT: fecal, oral
AIRBORNE: droplets, suspended particles
Prevent by hand hygiene, PPE, precautions
Portal of Entry → Anatomic and Physiologic barriers (skin, mucous membranes,
pH of environment, etc)
Prevent by using sterile technique, disposable items, mind open wounds
Susceptible Host → Age, nutrition, stress, disease, treatments/surgery/wounds
Prevented by immunizations, good skin care, good nutrition
- Infectious process -> 4 stages, Incubation period, Prodromal stage, Illness stage,
Convalescence.
, - Incubation period is the period between exposure to a pathogen and when
symptoms and/or signs are first apparent. This phase signifies the period taken by the
multiplying organism to reach a population necessary to produce symptoms in the host.
- Prodromal stage of an infectious illness is the period between end of incubation
period and the point at which the characteristic symptoms of the illness appear. A person in
the prodromal stage of an infectious illness often displays nonspecific symptoms, such as
fatigue or malaise.
- Illness stage is the phase of rapid multiplication of the pathogen with exponential
growth and peak in its’ population. Symptoms are very pronounced, both specific to the
organ affected as well as in general due to the strong response of the immune system.
- Convalescence period is the time the host recovers gradually and returns to
baseline. The pathogen load starts to decline, but may not be completely eliminated
immediately, hence the host may continue to be a source of infection even if feeling better.
Surgical vs. Medical Asepsis:
-Absence of pathogenic (disease producing) organisms.
-Aseptic technique is practice/procedure that assist in reducing the risk of
infections.
-There is TWO different types of asepsis: Medical asepsis aka clean technique
and surgical asepsis aka sterile technique.
-Medical Asepsis involves:
- reducing the number of organism present
- preventing the transfer or organisms
-Surgical asepsis involves:
- preventing the contamination of an open wound
- isolate the operative area from the unsterile environment
- PRINCIPLES OF SURGICAL ASEPSIS INCLUDE:
- Sterile object can only touch other sterile objects
- Only sterile object may be place on the sterile field
- A sterile field out of sight or below waist is considered contaminated
- A sterile field/object is contaminated by prolonged exposure to air
- When a sterile field/object touches a wet surface, they become contaminated.
- A 1” edge of the sterile field is considered contaminated.
Safety- Donning and Removing PPE: Gowns Gloves Face Mask/eyewear
Chapter 40 -Hygiene
Factors influencing personal hygiene
Social patterns
Body image
Health beliefs and motivations (culture)
Personal preferences
Socioeconomic status
Physical condition
cultural variables
developmental stage
Types of hygiene