Asepsis and Infection Control
Dr. sabah abbas
Asst. prof./University of Baghdad/Nursing college
OBJECTIVES:
1. Differentiate between medical asepsis and surgical asepsis
2. Differentiate among disinfection, and sterilization
3. Describe the the parts of the “ chain of infection, ” and give examples of how this chain can be broken.
4. Explain why it is important for medical assistants to understand the basic principles of infection control
5. Define, all the Key Terms for this chapter
Introduction:
Patients with infections and infectious disease regularly come to the medical facility for
treatment. As the medical assistant goes from patient to patient performing clinical
Procedures, such as taking vital signs and assisting the physician, the potential for
transmitting disease is high if the medical assistant does not follow protective measures such
as hand washing, sanitization, and proper handling of medical waste Infection control and
medical and surgical asepsis are crucial in medical facilities to prevent the spread of disease
and infection. Understanding and following the guidelines for breaking the“chain of
infection” protects not only the patients and other health care workers in the facility but also
the medical assistant.
Terminologies:
1-Asepsis:
- Medical asepsis(clean)
1. Includes all practices intended to confine a specific microorganism to a specific area
2. Limits the number, growth, and transmission of microorganisms .
3. Objects referred to as clean or dirty (soiled, contaminated)
-
Surgical asepsis (sterile)
1.
2.
3.
4.
Sterile technique
Practices that keep an area or object free of all microorganisms
Practices that destroy all microorganisms and spores.
Used for all procedures involving sterile areas of the body
2-Infection:
The invasion of the body by disease-producing microorganism and the
body's reaction to their presence
Signs of Localized Infection
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Localized swelling
Localized redness
Pain or tenderness with palpation or movement
Palpable heat in the infected area
Loss of function of the body part affected, depending on the site and extent of
involvement
Signs of Systemic Infection
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Fever
Increased pulse and respiratory rate if the fever high
Malaise and loss of energy
Anorexia and, in some situations, nausea and vomiting
Enlargement and tenderness of lymph nodes that drain the area of infection
Factors Influencing Microorganism’s Capability to Produce Infection
1- Number of microorganisms present
2- Virulence and potency of the microorganisms (pathogenicity)
3- Ability to enter the body Susceptibility of the host
4- Ability to live in the host’s body
3- Disinfection
: is the process of applying an antimicrobial agent to nonliving objects
to destroy pathogens and is considered an intermediate level of infection control. Disinfection
occurs when scrubbing or soaking an item with a chemical cleaning agent (e.g., 10% bleach
solution, alcohol). Disinfection destroys or inhibits the activity of microorganisms, but it has
no effect on spores
.
4-Sterilization:
destroys all microorganisms, including spores. Sterilization occurs by using
heat, steam under pressure, gas, ultraviolet (UV) light, or chemicals.
autoclave operation
5-Nosocomial
infections:
are those that occur as a result of treatment in a health
care facility (e.g., hospital, outpatient treatment center). Or also known as a hospitalacquired infection or HAI, is an infection whose development is favored by a hospital
environment, such as one acquired by a patient during a hospital visit
6 -Microorganisms:
are found in the air we breathe, on our skin, on everything we touch, and
even in our food. Microorganisms are so small that they can only be seen with a microscope.
Fortunately, not all microorganisms are harmful
7 - Pathogens:
are disease-producing microorganisms. When a pathogen invades a person who
has a weakened immune system, an infection can occur, possibly leading to death.
8-Cross –infection: Is an infection transmitted from an infected person or an object to
other persons or objects
9-Inflammation:
Inflammation is a response of a tissue to injury, often injury caused
by invading pathogens. It is characterized by:
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increased blood flow to the tissue causing
increased temperature,
redness,
swelling, and
pain.
10- Endemic
: The occurrence of certain diseases as they relate to a population or
geographic area.
11- Contamination :
Means to make something unclean, such as area
equipment, if it contains microorganisms that cause disease.
12-Antiseptic:
A substance used to destroy pathogens on living object such as skin
and mucous membrane.
13- Disinfectant :
A substance used to destroy pathogens but not necessarily their spores, in general not
intended for use on persons.
Chain of Infection
-The chain of infection refers to those elements that must be present to cause an
infection from a microorganism
- Basic to the principle of infection is to interrupt this chain so that an infection
from a microorganism does not occur in client
1.
-Infectious agent; microorganisms capable of causing infections are
referred to as an infectious agent or pathogen.:
.
a-. Bacteria: The most significant and most commonly observed infection-causing
agents in health care institutions
Can be categorized according to : .
1. Shape
-spherical (cocci)
-rod shaped (bacilli)
-corkscrew shaped (spirochetes)
2. Reaction to Gram stain
-Gram positive bacteria
- Gram negative bacteria
3. Bacterial is their need for oxygen
- Aerobic
- Anaerobic
Is the smallest of all microorganisms, visible only with an electron ‫ل‬
microscope, such as virus cause common cold and AIDS
b -. Viruses:
C -. Fungi:
Plant-like organism (molds and yeasts) that also can cause infection, are
present in the air, soil, and water.
.
Examples of disease cause by fungi include athlete's foot, ringworm, and yeast
infections.
2- Modes of transmission: the microorganism must have a means of transmission
to get from one location to another, called direct and indirect
3-Susceptible host describes a host (human or animal) not possessing enough
resistance against a particular pathogen to prevent disease or infection from
occurring when exposed to the pathogen; in humans this may occur if the person’s
resistance is low because of poor nutrition, lack of exercise of a coexisting illness
that weakens the host.
4-Portal of entry: the means of a pathogen entering a host: the means of entry can
be the same as one that is the portal of exit (gastrointestinal, respiratory,
genitourinary tract).
5-Reservoir: the environment in which the microorganism lives to ensure survival;
it can be a person, animal, arthropod, plant, oil or a combination of these things;
reservoirs that support organism that are pathogenic to humans are inanimate
objects food and water, and other humans.
6-Portal of exit: the means in which the pathogen escapes from the reservoir and
can cause disease; there is usually a common escape route for each type of
microorganism; on humans, common escape routes are the gastrointestinal,
respiratory and the genitourinary tract.
- Breaking the Chain of Infection
-Etiologic agent (Infectious agent)
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Correctly cleaning, disinfecting or sterilizing articles before use
Educating clients and support persons about appropriate methods to clean,
disinfect, and sterilize article
-Reservoir (source)
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Changing dressings and bandages when soiled or wet
Appropriate skin and oral hygiene
Disposing of damp, soiled linens appropriately
Disposing of feces and urine in appropriate receptacles
Ensuring that all fluid containers are covered or capped
Emptying suction and drainage bottles at end of each shift or before full or
according to agency policy
-Portal of exit
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Avoiding talking, coughing, or sneezing over open wounds or sterile fields
Covering the mouth and nose when coughing or sneezing
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Method of transmission
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Proper hand hygiene
Instructing clients and support persons to perform hand hygiene before
handling food, eating, after eliminating and after touching infectious material
Wearing gloves when handling secretions and excretions
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Wearing gowns if there is danger of soiling clothing with body substances
Placing discarded soiled materials in moisture-proof refuse bags
Holding used bedpans steadily to prevent spillage
Disposing of urine and feces in appropriate receptacles
Initiating and implementing aseptic precautions for all clients
Wearing masks and eye protection when in close contact with clients who
have infections transmitted by droplets from the respiratory tract
Wearing masks and eye protection when sprays of body fluid are possible
Portal of entry
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Using sterile technique for invasive procedures, when exposing open wounds
or handling dressings
Placing used disposable needles and syringes in puncture-resistant containers
for disposal
Providing all clients with own personal care items
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Susceptible host
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Maintaining the integrity of the client’s skin and mucous membranes
Ensuring that the client receives a balanced diet
Educating the public about the importance of immunizations
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Modes of Transmission
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1. Direct contact: describes the way in which microorganisms are transferred
from person to person through biting, touching, kissing, or sexual intercourse;
droplet spread is also a form of direct contact but can occur only if the source
and the host are within 3 feet from each other; transmission by droplet can
occur when a person coughs, sneezes, spits, or talks.
2. Indirect contact: can occur through fomites (inanimate objects or materials)
or through vectors (animal or insect, flying or crawling); the fomites or vectors
act as vehicle for transmission
3. Air: airborne transmission involves droplets or dust; droplet nuclei can remain
in the air for long periods and dust particles containing infectious agents can
become airborne infecting a susceptible host generally through the respiratory
tract
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Stages of Infection :
1. Incubation: the
time between initial contact with an infectious agent until the
first signs of symptoms the incubation period varies from different pathogens;
microorganisms are growing and multiplying during this stage
2. Prodromal Stage: the time period from the onset of nonspecific symptoms to
the appearance of specific symptoms related to the causative pathogen
symptoms range from being fatigued to having a low-grade fever with
malaise; during this phase it is still possible to transmit the pathogen to
another host
3. Full Stage: manifestations of specific signs & symptoms of infectious agent; referred
to as the acute stage; during this stage, it may be possible to transmit the infectious
agent to another, depending on the virulence of the infectious agent
4. Convalescence: time period that the host takes to return to the pre-illness stage;
also called the recovery period; the host defense mechanisms have responded to the
infectious agent and the signs and symptoms of the disease disappear; the host,
however, is more vulnerable to other pathogens at this time; an appropriate nursing
diagnostic label related to this process would be Risk for Infection
-The body's defense against infection
1. Body's normal flora
2. Inflammatory response
3. Immune response
- Body's normal flora:
Bacterial that normally cause no problem but, with certain
factors, may potentially be harmful are referred to as opportunists.
For example .one type of Escherichia coli normally resides in the intestinal tract and
causes no harm. However, if it migrates to the urinary tract ,it can lead to UTI
-. Inflammatory response: The inflammatory response is a productive mechanism that eliminates the invading
pathogen and allows for tissue repair to occur. The inflammatory response also occurs
in response to injury .it is either an acute or chronic process.
The vascular and cellular stages are the main component of the inflammatory
process and these physiological processes are responsible for the appearance of the
cardinal signs( redness , heat, swelling, pain, and loss of function)
-Immune response:The foreign material is called an antigen, and the body responds to the antigen by
producing an antibody. (humoral immunity)
-Cell mediated defense (cellular immunity)
Increase the number of lymphocytes (white blood cell)
Help to defend the body specifically against bacterial, viral , and fungal infections, as
well as malignant cell.
-Factors Increasing Susceptibility to Infection
Age:
young infants & older adults are at greater risk of infection because
of reduced defense mechanisms:
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Young infants have reduced defenses related to immature immune
systems
In elderly people, physiological changes occur in the body that make
them more susceptible to infectious disease
2- Heredity: some people have a genetic predisposition or susceptibility
to some infectious diseases.
3-Cultural practices:
healthcare beliefs and practices, as well as nutritional and hygiene practices,
can influence a person’s susceptibility to infectious diseases
4- Nutrition:
inadequate nutrition can make a person more susceptible to infectious
diseases; nutritional practices that do not supply the body with the basic components
necessary to synthesized proteins affect the way the body’s immune system can
respond to pathogens
5- Stress:
stressors, both physical and emotional, affect the body’s ability to protect
against invading pathogens; stressors affect the body by elevating blood cortisone
levels; if elevation of serum cortisone is prolonged, it decreases the anti-inflammatory
response and depletes energy stores, thus increasing the risk of infection
6- Rest, exercise and personal health habits:
altered rest and exercise patterns decrease the body’s protective, mechanisms
and may cause physical stress to the body resulting in an increased risk of infection;
personal health habits such as poor nutrition and unhealthy lifestyle habits increase
the risk of infectious over time by altering the body’s response to pathogens
7- Inadequate defenses:
any physiological abnormality or lifestyle habit can influence normal defense
mechanisms in the body, making the client more susceptible to infection; the immune
system functions throughout the body and depends on the following:
o Intact skin and mucous membranes
o Adequate blood cell production and differentiation
o A functional lymphatic system and spleen
8- Environmental:
an environment that exposes individuals to an increased number of toxins or
pathogens also increases the risk of infection; pathogens grow well in warm moist
areas with oxygen (aerobic) or without oxygen (anaerobic) depending on the
microorganism, an environment that increases exposure to toxic substances also
increases risk
9-Immunization history:
Inadequately immunized people have an increased risk of infection
specifically for those diseases for which vaccines have been developed.
10-Medications and medical therapies:
examples of therapies and medications that increase clients risk for infection
includes radiation treatment, anti-neo-plastic drugs, anti inflammatory drugs and
surgery