WEEK 5 Flashcards
chain of infection
sequence of factors needed for an infection to occur. It includes the following links:
presence of an infectious agent, an available reservoir, a portal of exit from the reservoir, a mode of transmission from the reservoir to a host, and a portal of entry to enter a susceptible host.
A break in any of the links of this chain can prevent the development of an infection.
Chain of Infection: Infectious Agent
something that contains a bacterium, fungus, virus, parasite, or prion
example of infectious agent
An individual’s resident flora—that is, the bacteria that live on or in a client and help protect the body from infection—can become an infectious agent when moved to a different location of the body; for example, flora from the gastrointestinal tract can move elsewhere in the body and create infection there.
How must infectious agents be destroyed?
disinfecting, sterilizing, and cleaning or through antimicrobial treatment (antibiotics, antifungals)
Chain of Infection: Resevoir
habitat of the infectious agent—where it lives, grows, reproduces, and replicates itself.
can be an animate or inanimate object (animals and humans, or soil, water, food, medical equipment, door handle, feces, etc)
How to break chain of infection with resevoirs?
nurses should use proper hand hygiene when caring for clients, clients should receive preoperative skin preparation prior to surgery, and the clinical or surgical environment should be cleansed properly by following the facility’s protocols to prevent infection.
Chain of Infection: Portal of Exit
the route by which an infectious pathogen can leave the reservoir
can be any body orifice—for example, ears, nose, or mouth—or can even be the skin. Any of these sites can provide a place for the infectious agent to replicate or for the toxin to act. and bodily fluids too.
How to break chain of infection with portal of exit?
careful containment of body fluids through usage of drains or dressings can be implemented, and methods can be used to decrease body secretions.
Chain of Infection: Mode of Transmission
How bacteria, viruses, fungi, parasites, and prions move from place to place. These are contact, droplet, and airborne.
What are the modes of transmission?
contact, droplet, airborne, vehicle, and vector-borne transmission.
How to break chain of infection with modes of transmission?
Hand hygiene and use of proper barrier devices can help break the chain of infection by eliminating various modes of transmission.
Chain of Infection: Portal of Entry
Any body orifice–for example, ears, nose, mouth, or skin–that provides a place for an infectious agent to replicate or for a toxin to act.
Can the portal of entry and portal of exit be the same?
yes, such as influenza. it both enters and exits the respiratory tract
Chain of Infection: Susceptible Host
required for the infectious agent to take hold and become a reservoir for infection.
How to decrease host susceptibility?
Immunizations, proper nutrition, dietary supplements, proper hygiene, and control of blood sugar
virulent
term to describe how efficient an infectious agent is at making people ill
What are the three main modes of transmission?
contact-transmitted by contact with an object or person
droplet-transmitted through droplets such as sneezing, coughing, and singing
airborne-transmitted through the air
contact transmission-direct and indirect
direct-Occurs when micro-organisms are directly moved from an infected person to another person, rather than through a contaminated object or person.
example of direct-a client’s blood coming in contact with an open abrasion on a nurse’s skin
indirect-that is, from an infected person to another person via a contaminated object or person.
example-staph infections in the hospital. drainage from a client’s wound might get on the bed rail or a bedside table, which others then touch
EXAM QUESTION!
airborne transmission
occurs when small particulates found in the air move into the airspace of another person and carry infectious agents.
examples: tuberculosis, rubeola (measles), and varicella (chickenpox).
how to treat client will illness that is airborne
For this reason, clients who have an infection that can be transmitted through the airborne route require placement in a private room with negative air pressure.
droplet transmission
occurs when infectious droplets from a client travel through the air and come in contact with the mucosa of a host (i.e., nurse, other client, health care worker).
examples: influenza virus and Bordetella pertussis
what medical procedures can release droplets into the air?
cardiopulmonary resuscitation (CPR), endotracheal intubation, and chest physiotherapy can release droplets into the air.
what are the three specific types of body defenses to fight off pathogens?
physical and chemical barriers, nonspecific immunity, and specific immunity
These defenses involve external and internal body structures, such as skin and white blood cells.
physical and chemical barriers
The skin is the body’s largest organ and is the primary physical defense mechanism. The skin performs three major functions:
Reduce loss of water
Protect against abrasion and micro-organisms
Provide a permeable barrier against the environment
intact skin the most important components in fighting infection
nonspecific immunity
maintained by neutrophils and macrophages—both are types of white blood cells—and their work as phagocytes.
EXAM QUESTION!
specific immunity
refers to the work of antibodies (also called immunoglobulins) and lymphocytes. Antibodies bind to infectious agents and activate the white blood cells and complement to destroy the infectious agent.
inflammatory response
Natural defense of the body when injured, when foreign substances are present or when infectious agents attack.
basic steps of inflammation
Recognition of harmful stimuli by pattern receptors (located on the surface of cells)
Activation of the inflammatory pathway
Release of inflammatory markers
Recruitment of inflammatory cells
inflammatory response triggers: infectious triggers
Viruses
Bacteria
Other micro-organisms
inflammatory response triggers: noninfectious triggers
Physical: burns, frostbite, injury, foreign bodies, trauma, radiation
Chemical: glucose, fatty acids, toxins, alcohol, irritants (e.g., fluoride, nickel)
Biological: damaged cells
Psychological: excitement
example of inflammation as a solitary response?
a client might get struck in the face while playing baseball. The face swells and then resolves, so that this is a solitary event.
when would inflammation repeat itself?
a client who has asthma develops bronchial swelling, and its resolution occurs chronically.
gastroesophageal reflux disease (GERD) causes acid to regurgitate into the esophagus. This acid causes erosion, followed by inflammation to heal the erosion. This cycle happens repeatedly, leaving the client with GERD in a constant state of inflammation.
manifestations of inflammation
heat
redness
swelling
pain
loss of function
place the findings in the order in which the occur during the inflammatory process
Bacteria invade an open wound (the pattern receptors on the surface cells recognize the bacteria as harmful stimuli) 2. Histamine, Kinins, and Prostaglandins (the inflammatory mediators are released) 3. Plasma from the blood enters the site (blood flow is increased to the site causing erythema and heat. Plasma from the blood causes swelling and pain at the site) 4. Phagocytosis occurs (the increased blood flow brings in more WBCs to the site and they begin to wall off the infection and destroy the harmful stimuli and the affected cells – bacteria) 5. Pus develops (the containment of the destroyed pathogen and the affected cells as well as the WBCs)
stages of infection
incubation
prodromal
acute illness
period of decline
period of convalescence
local vs systematic infections
local-are confined to one area of the body. These infections can be treated with topical antibiotics and oral antibiotics.
systematic-start as local infections and then move into the bloodstream, from which they infect the entire body. Intravenous antibiotics and careful monitoring are both needed to treat systemic infections.
types of antiseptic agents
Alcohols
Chlorhexidine
Chlorine
Chloroxylenol (parachlorometaxylenol [PCMX])
HexachloropheneIodine/iodophors
Quaternary ammonium compounds
Triclosan
how short should you keep your nails
less than 0.25 inches