Infection Flashcards
These are infections that patients acquire during the course of medical treatment. I
Health care-associated infections (HAIs)
Approximately how many percent of all patients admitted to a hospital develop an HAI, and how many percent of HAIs are pneumonias.
5%, 15%
Infection control procedures aim to
eliminate the sources of infectious agents, create barriers to their transmission, and monitor and evaluate the effectiveness of control.
People may also serve as their own source of infection, via_______ This latter process is called_______
endogenous flora, autogenous infection
What are the susceptible host factor that can enhance susceptibility
poorly controlled diabetes mellitus, extremes of age, and underlying acquired (HIV infection) or iatrogenic (through chemotherapy or anti-tumor necrosis factor inhibitors) immunodeficiency
These are infections that are acquired in the hospital.
Hospital-acquired or nosocomial infections
Three elements must be present for transmission of infection within a health care setting:
a source (or reservoir) of pathogens, (2) a susceptible host, and (3) a route of transmission for the pathogen
Patients with an artificial tracheal airway are at high risk for_________ for several reasons
nosocomial pneumonia
The three major routes for transmission of human sources of pathogens in the health care environment are
contact (direct and indirect), respiratory droplets, and airborne droplet nuclei (respirable particles <5 µm).
The three major routes for transmission of human sources of pathogens in the health care environment are
contact (direct and indirect), respiratory droplets, and airborne droplet nuclei (respirable particles <5 µm).
It is the most common route of transmission
Contact transmission
Two types of contact transmission
Direct and indirect
It occurs when a pathogen is transferred directly from one person to another
Direct contact
It is the most frequent mode of transmission in the health care environment and involves the transfer of a pathogen through a contaminated intermediate object or person
Indirect contact
Inanimate objects that may serve to transfer pathogens from one person to another are called_________
fomites
It is a form of contact transmission, but the mechanism of transfer of the pathogen is distinct, and additional prevention measures are required.
Droplet transmission
Organisms that are transmitted by respiratory droplets include
influenza and Neisseria meningitidis
Transmission occurs when infectious droplets are propelled (usually what distance) and are deposited on another person’s mouth or nose.
≤3 feet through the air
occurs via the spread of airborne droplet nuclei.
Airborne transmission
These are small particles (≤5 µm) of evaporated droplets containing infectious microorganisms that can remain suspended in the air for long periods
airborne droplet nuclei
Examples of pathogens transmitted via the airborne route include
Mycobacterium tuberculosis, varicella-zoster virus (chickenpox), and rubeola virus (measles).
Types of aerosol transmission
obligate, preferential, opportunistic
Under natural conditions, disease occurs after transmission of the microorganism through small-particle aerosols.
Obligate transmission
Natural infection results from transmission through multiple routes, but small-particle aerosols predominate
Preferential transmission
Microorganisms that cause disease through other routes but under certain environmental conditions may be transmitted via fine-particle aerosol (e.g., SARS transmission via an aerosol plume that originated from sewage in the Amoy Gardens housing complex).
Opportunistic transmission
occurs via exposure to pathogens in contaminated food, water, or medications
(e.g., heparin solution).
Common vehicle transmission
Transmission of infectious diseases from insects and rats and other vermin occurs but is of less significance in U.S. health care facilities.
Vector-borne
It is the most difficult and least feasible approach to infection control.
Decreasing inherent host susceptibility to infection
Hospital efforts at this level focus mainly on
employee immunization and chemoprophylaxis
Meaning of OSHA
Occupational Safety and Health Administration
The best way to decrease host susceptibility to a device-related infection is
first to_______ and second_________
limit device use, to ensure that devices are placed and maintained appropriately
defined as the use of multiple different evidence-based best practices to prevent device-related infection
Prevention bundles
Infection control procedures designed to remove environmental pathogens fall into two major categories:
general sanitation measures and specialized equipment processing
aims to reduce the number of pathogens to a safe level. This reduction is achieved through sanitary laundry management, food preparation, and housekeeping.
General sanitation
The goal of______ is to decontaminate equipment capable of spreading infection.
Equipment processing involves cleaning, disinfection, and sterilization (when necessary).
specialized equipment processing
Methods that kill bacteria are______, whereas methods and techniques that
inhibit the growth of bacteria are_______ . Methods that destroy spores are__________ , and methods that destroy viruses are_______
bactericidal, bacteriostatic, sporicidal, virucidal
There are two tiers of HICPAC and the Centers for Disease Control and Prevention (CDC) transmission precautions:
standard precautions and transmission-based precautions.
These precautions are intended to be applied to the care of all patients in all health care settings all the time. This is the primary strategy for the prevention of healthcare-associated transmission of infections among patients
and health care personnel.
Standard precautions
refers to various barriers and respirators used alone or in combination to
protect mucous membranes, skin, and clothing from contact with infectious agents
PPE
It includes handwashing with either plain or antiseptic-containing soap and water for at least 15 seconds and the use of alcohol-based products (gels, rinses, and foams) containing an emollient that does not require the use of water.
Hand hygiene
It is an important component of standard precautions because the mucous membranes of the eyes, nose, and mouth are particularly vulnerable to some types of pathogens.
Face protection
It protect mucosal surfaces against splashes or sprays
Masks
It protects caregivers from contamination when contacting blood, body fluids, secretions, excretions, mucous membranes, and nonintact the skin of patients and when handling or touching visibly or potentially contaminated patient care equipment and environmental surfaces
Gloves
Caregivers should wear sterile gloves whenever performing______. A single pair of________ (e.g., latex, vinyl, nitrile) may be used for routine patient care.
invasive procedures, non-sterile disposable gloves
It (use of NIOSH-approved N-95 or higher-level respirator) is intended for diseases (e.g., M. tuberculosis, SARS, smallpox) that could be transmitted through the airborne route.
Respiratory protection
The term respiratory protection has a regulatory context that includes components of the program required by OSHA to protect workers:
- medical clearance to wear a respirator, (2) provision and use of appropriate NIOSH-approved fit-tested respirators, and (3) education in respirator use.
It also provides barrier protection and can prevent the contamination of clothing and exposed body areas from blood and body fluid contact and transmissible pathogens (e.g., respiratory syncytial virus and Clostridium difficile).
Isolation gowns and other apparel (aprons, leg coverings,
boots, or shoe covers)
The elements of respiratory hygiene/cough etiquette include
(1) education of health care personnel, patients, and visitors; (2) posted signs in language appropriate to the population served with instructions for patients and accompanying family members or friends; (3) source control measures (covering the mouth and nose with a tissue when coughing or placing a surgical mask on a coughing person when possible); (4) hand hygiene after contact with respiratory secretions; and (5) spatial separation (≥3 feet from persons with respiratory infections in common waiting areas)
refers to isolation techniques intended to reduce the risk of selected infectious agents transmitted by “small droplets” of aerosol particles (e.g., M. tuberculosis).
AI or Airborne Isolation
A specialized engineering approach to protect highly immunocompromised patients is a________. A________ is used for patients with allogeneic hematologic stem cell transplants to minimize fungal spore counts in the air.
protective environment, protective environment
It is a practice of grouping patients with the same infection (or colonized with the same organism) together to confine care geographically and prevent transmission to other patients.
Cohorting
Removal of all foreign material (e.g., soil, organic material) from objects
Cleaning
Inactivation of all microorganisms except bacterial spores (with sufficient exposure times, spores may also be destroyed)
Disinfection,
high-level
Complete destruction of all forms of microbial life
Sterilization
Inactivation of all vegetative bacteria, most viruses, most fungi, and M. tuberculosis, without destruction of bacterial spores
Disinfection,
intermediate-level
Inactivation of most bacteria, some viruses, and fungi, without destruction of resistant microorganisms such as Mycobacterium tuberculosis or bacterial spores
Disinfection,
low-level
Inactivation of most pathogenic organisms, excluding spores
Disinfection
general term
The five key components to bronchoscope reprocessing are
cleaning, disinfecting, rinsing, drying, and storage
What bronchoscope offers many advantages over manual disinfection because they automate several
steps.
Automated bronchoscope reprocessors (ABRs)
In what year does , who published his approach to disinfection
and sterilization, which was based on the degree of risk of
infection involved in the use of the item in patient care.
1968, Spaulding
These items are categorized based on the high risk of infection if such an item is contaminated with pathogens, including bacterial spores (e.g., items that enter sterile tissue or the vascular system).
Critical items
Most of these critical items should be purchased
sterile or be sterilized, by steam sterilization if possible
These items come into contact with mucous membranes or nonintact skin; this includes most respiratory equipment.
Semicritical
These items should be free of all microorganisms before use (bacterial spores may be present). Semicritical items require at least________ using chemical disinfectants.
high-level disinfection
These items come into contact with intact skin (an effective barrier to
most microbes) but not mucous membranes
Noncritical items
It is the first step in all equipment processing. It involves removing
dirt and organic material from equipment, usually by washing.
Cleaning
Examples of critical items
surgical devices Intravascular catheters Implants Heart-lung bypass components Dialysis components Bronchoscope forceps/brushes
Examples of semicritical
Bronchoscopes Oral, nasal, and tracheal airways Ventilator circuits/humidifiers PFT mouthpieces and tubing Nebulizers and their reservoirs Resuscitation bags Laryngoscope blades/stylets Pressure, gas, or temperature probes
Examples of noncritical items
Face masks Detergent washing
Blood pressure cuffs
Ventilators
Describes a process that destroys the vegetative form of all pathogenic organisms on an inanimate object except bacterial spores
Disinfection
By definition, disinfection differs from sterilization by its lack of_______
sporicidal activity
The most common physical method of disinfection is
pasteurization
It involves the application of chemical solutions to contaminated surfaces or equipment
Chemical disinfection
destroys all microorganisms on the surface of an article or in a fluid, which prevents transmission of pathogens associated with the use of that item.
Sterilization
Physical methods include various forms of_______ .Chemical methods of sterilization include_______
heat (steam) and ionizing radiation, low-temperature sterilization technologies such as ethylene oxide (EtO) gas.
It is the most common, most efficient, and easiest sterilization method.
Moist heat in the form of steam under pressure
It (steam sterilization) is the application of steam under pressure. It is efficient, quick, cheap, clean, and reliable.
Autoclaving
The combination most commonly used for autoclaving is psi at ° C
15, 121
It is a modification of conventional steam sterilization in which the item is placed in an open tray or a specially designed container to allow for rapid penetration of steam.
Flash “steam sterilization”
are needed for sterilizing temperature-sensitive and moisture-sensitive medical devices and equipment
Low-temperature (<60° C) sterilants
Low-temperature sterilant technology includes
EtO, hydrochlorofluorocarbon, hydrogen peroxide gas plasma, and peracetic acid
It is a colorless, toxic gas and potent sterilizing agent. Because it is active at ambient temperatures and is harmless to rubber and plastics,
EtO
EtO must be removed from equipment after sterilization
via a process called_______ .______ is used to sterilize critical
(and sometimes semicritical) items that cannot be steam
sterilized
aeration, EtO
It has an efficiency rate of 99.97%, and the use of ensheathed suction catheters, help reduce endotracheal tube contamination.
high-efficiency particulate air/aerosol (HEPA) filters
It poses the most significant contamination risk, particularly in systems using
heated humidifiers
The external ventilator circuitry
are a source for colonizing both the airways of intubated patients and the hands of medical personnel
Bag-mask devices
_______suctioning increases the risk of infection. Proper
handwashing and gloving help minimize this risk.
Tracheal suctioning
To minimize the risk of cross-contamination during suctioning with an open system, a_______ should be used on each patient.
fresh, sterile single-use catheter
In-use_________ have a contamination rate of 33%
nondisposable oxygen humidifiers
Three major issues are involved in using disposable
devices:
cost, quality, and reuse
It is an ongoing process of monitoring patients and health care personnel for the acquisition of infection or colonization of pathogens, or both.
Surveillance
What are the five key recommended components of an infection prevention
program
Surveillance, investigation, prevention, control, and
reporting
It is a tool to provide HAI data on patients to provide outcome measurements either to ensure that there is no ongoing problem or to detect problems and intervene to prevent transmission of pathogens in the health care environment.
Surveillance
It fulfills a central role in surveillance for HAIs and community-acquired
pathogens (e.g., influenza) that are important for the infection control practitioner
The hospital microbiology laboratory
organisms in active growth. These organisms pose the greatest hazard for infection via respiratory therapy equipment because the most common equipment contaminants are not spore-forming bacteria
Vegetative organism
organisms in a resting, resistant stage. These are very difficult to kill but pose little threat to infection via respiratory therapy equipment. Examples of
spore-forming bacteria are Clostridium and Bacillus.
Spores
The killing of all vegetative forms of organisms but not spores. Agents that disinfect equipment are called disinfectants.
Disinfection
The killing of all organisms, both vegetative and spores. An agent that sterilizes equipment is called a sterilant.
Sterilization
It is used for differential staining of bacteria. Gram-positive bacteria stain a_______ ; gram-negative bacteria stain a______ color.
The Gram stain method, purple-black color. pink
Three main classes of bacteria
Cocci: Sphere-shaped bacteria
Spirillum: Spiral-shaped bacteria
Bacilli: Rod-shaped bacteria
Gram- negative bacteria causing pneumonia
Klebsiella pneumoniae, Pseudomonas aeruginosa, Legionella species, Serratia marcescens, Haemophilus influenzae
are the bacteria most frequently encountered on respiratory equipment
Bacilli
