Unit 2 Infection Control Flashcards
1
Q
Cycle of Infection
A
•Infectious organisms
•Reservoir of Infection
•Portal of exit
•Susceptible host
•Portal of entry
•Transmission of disease
2
Q
Microorganisms capable of causing disease are called
A
pathogens or pathogenic organisms
3
Q
Reservoir of Infection
A
•Place where pathogens can thrive in sufficient numbers to pose a threat
•Must have:
➢Moisture
➢Nutrients
➢Suitable temperature
•May be human or nonhuman (e.g., food, water, animals)
4
Q
Portal of Exit and examples
A
Any route through which blood, body fluids, excretions, or secretions leave the body
•Examples:
➢GI tract
➢Open wound
➢Respiratory tract
5
Q
Susceptible Hosts
A
•Patients are often hosts because of a reduced immune system.
•Nosocomial infection, also called HAI
➢hospital-acquired infection
➢health care-associated infection
•Healthcare workers are also at risk.
➢Exposure to blood and other bodily fluids
6
Q
Nosocomial infection is a
A
hospital-acquired infection
7
Q
Portal of Entry and examples
A
•The route by which microorganisms gain access into the susceptible host
•Examples:
➢Respiratory tract
➢Urinary tract
➢GI tract
➢Open wound or break in skin
➢Mucous membranes of the eyes, nose, or mouth
➢Bloodstream
8
Q
Transmission of Disease
A
Most direct way to break the cycle of infection is to prevent transmission of the infectious organism from the reservoir to the susceptible host
9
Q
Six main routes of transmission of disease
A
➢Direct contact
➢Fomites
➢Vectors
➢Vehicles
➢Airborne
➢Droplet contamination
10
Q
Direct Contact and examples
A
•Infected person must touch susceptible host.
•Requires the pathogens to be placed in direct contact with susceptible tissue
•Examples:
➢Syphilis
➢HIV infections
➢Staph infections
11
Q
Fomites and examples
A
•An object that has been in contact with pathogenic organisms
•Examples:
➢Contaminated gloves
➢X-ray table
➢Positioning sponges
12
Q
Vectors and examples
A
•An arthropod in whose body an infectious organism develops or multiplies before becoming infective to a new host.
•Transmission occurs when an infected insect bites host.
•Examples:
➢Mosquitos—malaria
➢Ticks—Lyme disease
13
Q
Vehicles and examples
A
•Any medium that transports microorganisms
•Examples:
➢Contaminated food, water, drugs, or blood
14
Q
Droplet Contamination
A
Occurs when an infectious individual coughs, sneezes, speaks, or sings in the vicinity of a susceptible host
•Involves contact of the mucous membranes of the eyes, nose, or mouth of a host with large droplets (greater than 5 µm) that contain microorganisms
- Travel 3ft at most
15
Q
How far do droplets travel
A
3 feet or less
16
Q
Droplet contamination examples
A
➢Influenza
➢Meningitis
➢Diphtheria
➢Pertussis
➢Streptococcal pneumonia
17
Q
Airborne Transmission
A
Occurs from dust that contains spores or by means of droplet nuclei
➢Droplet nuclei are particles of evaporated droplets containing microorganisms and measuring 5 microns (micrometers, µm, 0.001 mm) or smaller.
➢Can remain suspended in the air for long periods
18
Q
Airborne examples
A
➢TB
➢Varicella viruses like chickenpox (also transmitted via direct contact)
19
Q
Natural Resistance
A
Provided by mechanical barriers of intact skin and mucous membranes
-Skin
-Mucous membranes
-Body’s chemicals
-Inflammatory response
-Interferons
20
Q
Acquired Immunity (long term)
A
Occurs when an individual develops antibodies to a particular organism as a result of either infection or immunization
-History with the disease
-Vaccines
-Build antibodies
21
Q
Passive Immunity
A
Occurs following an injection of preformed antibodies to a particular infection
• Patients given antibodies and they “go to work” to prevent the disease
• Weaken over time
• Newborns have passive immunity from mom’s circulatory system and may continue with breastfeeding
• Short term because individual’s own body is not producing the antibodies
22
Q
Emerging Diseases
A
➢New diseases appearing in the population
➢Existing diseases that are rapidly increasing in incidence or geographic range
➢Resurgent or recurrent old diseases caused by an old or mutated pathogen
23
Q
What are the Infection-control departments of hospital responsible for keeping up-to-date emerging diseases?
A
➢CDC: recommendations, recommends hospitals or healthcare settings in ways to prevent spread of infection
➢WHO: studies, collects, and complies infection data all around the world
24
Q
Disease emergence is precipitated by many factors:
A
➢Increased human exposure to vectors in nature
➢Population growth and migration to crowded cities
➢Rapid international travel and transportation of goods
➢Contact with new strains of dangerous pathogens
➢Pathogen mutation caused by overuse of antimicrobial agents
➢Breakdown in public health measures
➢Climate change
➢Bioterrorism
25
Healthcare-Associated Infections (HAI)
Those that occur more than 48 hours after patient admitted to the hospital
26
Which infections are multi-drug resistant?
➢MRSA
➢VRE
27
Clostridium difficile
a gastrointestinal infection that causes diarrhea.
•Caused by a Gram-positive bacillus
•Difficult to control because it cannot be eliminated by routine asepsis methods
•Patients on antibiotics most susceptible
28
Bloodborne Pathogens
•HIV
•AIDS
•Hepatitis
•Needle-stick injuries are most common cause of transmission from patients to healthcare workers
29
Tuberculosis
•A contagious, airborne lung disease caused by M. tuberculosis
•Most patients are homeless, recent immigrants, or immunocompromised.
•Pre-employment screening required for healthcare workers and after known exposure
30
Preventing Disease Transmission
•Historical Perspective
•Standard Precautions
•OSHA Bloodborne Pathogens Standard
•Medical Asepsis
•Handling and Disposal of Contaminated Items and Waste
•Isolation Technique
31
Historical Perspective
•Quarantines were used to contain infectious diseases.
➢Not allowed to leave the house and no one could enter until all members were well
Isolation no longer commonly used, but still a legal practice of the U.S. Public Health Service for diseases such as
➢Cholera
➢Diphtheria
➢Smallpox
➢TB
➢Plague
➢Yellow fever
➢SARS
32
Protective measures of the past: Universal precautions vs Body substance precautions
➢Universal Precautions—focused on barriers against bloodborne pathogens
➢Body Substance Precautions—expanded protection to all moist body secretions
33
Standard Precautions (Current infection-control system)
Designed to reduce risk of transmission of infections from unrecognized sources of bloodborne diseases and from other pathogens in healthcare institutions
•Includes transmission-based precautions for:
➢Airborne
➢Droplet
➢Contact
34
OSHA (Occupational Safety and Health Administration) Bloodborne Pathogens Standard
Published in 1991
•Requires employers to
➢develop an exposure-control plan for the work site that describes employee protection measures.
➢include engineering and work-practice controls to ensure the use of personal protective clothing and equipment.
➢provide signs and labels to identify biohazard materials.
➢provide annual bloodborne pathogen training, hepatitis B vaccinations, and medical care in the event of occupational exposure.
35
What does OSHA stand for?
Occupational Safety and Health Administration
-a federal agency governing safety in the workplace, provides guidelines to ensure a high level of safety for hospital workers
36
Medical Asepsis
•Involves REDUCING the probability of infectious organisms being transmitted to a susceptible individual
37
Medical Asepsis: Microbial dilution
the process of reducing the number of organisms
➢Hand hygiene and other cleanliness measures
➢Disinfection
➢Sterilization (surgical asepsis)
38
Hand Hygiene
•Washing for 30–60 seconds with soap and water
•Alcohol-based rubs
➢More effective at killing some HAI organisms,
such as C. difficile
➢More convenient than accessing sinks
➢Box 9-1 provides CDC guidelines for use
39
Cleaning Techniques
•Cleaning reduces the incidence of airborne infections and the transfer of pathogens by fomites.
•Always clean from the least contaminated area toward the more contaminated area and from the top down.
•Avoid raising dust.
•Do not contaminate yourself or clean areas.
•After each use, clean all equipment that comes in contact with patients. Use a cloth moistened with disinfectant.
40
CDC recommends __________________________________ as an inexpensive, effective disinfectant for preventing the spread of HIV.
sodium hypochlorite bleach (Clorox)
41
How to use sodium hypochlorite bleach (Clorox)
Mix bleach in a 1:10 solution daily because its effectiveness declines rapidly when diluted.
42
Handling and Disposal of Contaminated Items and Waste
Replace linens after each patient.
•To dispose of contaminated linens
➢fold edges to the middle without shaking or flapping.
➢place loosely balled linens in designated hamper.
•Sharps container is proper disposal for needles.
•Blood-contaminated items (gauze, bandages) also have designated “Biohazard” disposal containers.
43
To dispose of contaminated linens
➢fold edges to the middle without shaking or flapping.
➢place loosely balled linens in designated hamper.
44
Radiography of Isolation Patient
•Requires two technologists:
➢One has all patient contact (dirty tech)
➢Other has no patient contact—only handles equipment (clean tech)
45
Precautions for Compromised Patients
•Includes neonates, organ transplants, burn victims, and those receiving chemotherapy
•Older terminology—protective isolation or reverse isolation
•May require a modified surgical aseptic technique.
•Two radiographers are recommended for imaging procedures(clean tech handles the patient, dirty tech handles equipment)
46
Surgical asepsis
The process of creating and maintaining an area that is COMPLETELY free of pathogens
47
Sterilization
The complete destruction of all organisms and spores from equipment used to perform patient care or procedures
48
Chemical Sterilization
The immersion and soaking of clean objects in a bath of germicidal solution followed by a sterile water rinse
49
T or F: Chemical sterilization is not recommended for surgical asepsis
Why or why not?
True;
One of the less satisfactory methods because control of effectiveness factors (time, solution strength and temperature, and contamination detection) is difficult
50
Autoclaving
An autoclave is a device that provides steam sterilization under pressure.
-most common and most effective method for surgical instruments and trays
51
The most commonly used sterilization method is? Why?
Autoclaving;
Quickest and most convenient means for items that can withstand heat and moisture
52
Conventional Gas Sterilization
•Method that uses a mixture of gases heated to 135°F (57°C)
•Used for items that cannot be autoclaved
➢Electrical, plastic, rubber items, and optical ware
➢Telephones, stethoscopes, blood-pressure cuffs, and other equipment used in isolation rooms
53
Drawbacks of using Conventional Gas Sterilization
➢Gases used are poisonous.
➢Must be dissipated by aeration in a controlled environment.
➢Process is time-consuming.
54
Gas Plasma Technology
•Safer than conventional gas sterilization
➢No toxic by-products
•Able to sterilize heat/moisture-sensitive items in greater volume
➢More cost-effective than conventional gas
➢Cannot completely replace gas because it is not effective on items with long, narrow lumina
➢Cannot be used on cellulose items (linens, etc.)
55
Dry Heat
•Method used more in Great Britain and tropical countries
•Many types
➢Vacuum chamber with an infrared heating element is most popular and effective.
•Temperature ranges from 329°F to 338°F (165°C to 170°C)
•Less expensive than autoclaves
56
Dry Heat Advantages and Disadvantages over Autoclave and Gas
•Advantages over autoclave and gas:
➢Needs only for heat to penetrate, whereas other methods must come into direct contact with the surfaces of the objects to be effective
➢More effective for articles in sealed tubes or containers, and for powders and ointments
•Disadvantages:
➢Requires 1–6 hours
➢Some objects cannot withstand high temperatures.
57
What are Sterility Indicators? What are they used for? Where are they placed?
•Chemical indicators that change color when sterilization has occurred
•Used to identify whether a pack has been sterilized
•Placed inside and outside the pack to show that the gas, heat, steam, or gas plasma has penetrated to all surfaces
58
Sterile Field
Defined as a microorganism-free area prepared for the use of sterile supplies and equipment
59
Steps to Establish a Sterile Field
•Place the pack on a clean surface within reach of the physician.
•Just before the procedure begins, break the seal and open the pack.
•Unfold the first corner away from you; then unfold the two sides.
•Pull the front fold down toward you and drop it.
-Do not touch the inner surface.
•The inner wrap, if there is one, is opened in the same manner.
•You have now established a sterile field.
60
Surgical Asepsis: Standard Principles
•Any sterile object or field touched by an unsterile object or person becomes contaminated.
•Never reach across a sterile field.
-Organisms may fall from your arm into the field.
-Increases the risk of brushing the area with your uniform
•If you suspect an item is contaminated, discard it.
-Includes damp items, items with broken seal, and items on which the indicator tape has not assumed the correct color
•Do not pass between the physician and the sterile field.
61
Skin Preparation for Sterile Procedures
1.Obtain a “skin-prep set” and a bottle of antiseptic for painting the skin. The preparation set includes a basin, liquid soap such as pHisoderm, gauze sponges, razor, towel, forceps, and medicine cup.
2.Perform hand hygiene.
3.Place the patient in a comfortable position and ensure privacy.
4.Explain what is to be done.
5.Expose an area slightly larger than the preparation site, keeping the patient as completely covered as possible to provide
Note: If hair removal is not ordered, omit steps 6 and 7.
6.If hair removal is ordered, use a dry razor to shave a small area at a time. Hold the skin taut with one hand and shave with short, firm strokes in the direction of hair growth. The same concept applies if using an electric razor.
7.Wipe the area with a sterile gauze sponge wetted with alcohol, removing all the hair.
8.Perform hand hygiene and don sterile gloves.
9.Pour a little of the antiseptic into a waste container to cleanse the lip of the bottle.
10.Fill the medicine cup with antiseptic.
11.Grasp several gauze sponges with the forceps and dip them into the antiseptic.
12.Paint the skin with the antiseptic, starting in the center of the area and working outward in a circular pattern. Do not scrub harshly, but remember that friction is more effective than soap in cleansing the skin. Discard the sponge.
13.Allow the skin to dry.
14.Repeat steps 12 and 13.
15.Open the pack containing the sterile drape or sterile towels. The physician, wearing sterile gloves, will drape the area surrounding the
62
Surgical Hand Scrub: Traditional
1.Wear surgical attire and appropriate personal protective equipment.
2.Using foot or knee lever, adjust water flow and temperature.
3.Wet your hands. Add a few drops of antimicrobial soap and more water as needed to make a lather.
4.Wash your hands and forearms thoroughly. Use one brush and soap to clean your hands and nails, and clean under your nails with the nail cleaner under running water.
5.Rinse your hands and arms thoroughly
6.The fingers and hands should be visualized as having four sides, and each side must be effectively scrubbed. Starting with the fingernails, scrub them vigorously, holding the brush perpendicular to them. Then scrub all sides of each finger and the palms and backs of the hands. Divide each forearm into thirds and use a circular motion to scrub each side of the forearms and elbows, up to 2 inches above the elbows.
7.Keep your hands above your elbows while scrubbing and add small amounts of water as needed to maintain a good lather.
63
Surgical Scrub: Alcohol-based Handrub Method
1.Wear surgical attire and appropriate personal protective equipment.
2.Using foot or knee lever, adjust water flow and temperature.
3.Wet hands and arms and lather with approved non-antimicrobial agent.
4.Clean fingernails under running water using disposable nail cleaner; discard nail cleaner.
5.Rinse hands and arms under running water.
6.Dry hands and arms using a paper towel.
7.Dispense of the manufacturer’s recommended amount of alcohol-based hand rub into the palm
8.Dip the fingertips of the opposite hand into the hand prep and work it under the nails.
9.Spread the remaining hand prep evenly over the hand and forearm to just above the elbow, covering all surfaces.
10.Using additional hand prep, repeat steps 7–9 with the other arm.
11.Repeat steps 7–10, if recommended.
12.To facilitate drying, continue rubbing antiseptic hand prep into hands until dry.
13.Keep scrubbed hands and arms in view and avoid contamination; allow to air dry completely
64
Sterile Gowning with Closed Gloving Technique
1.Assistant opens gloves and sterile gown pack.
2.Lift folded sterile gown, and step back from table. Allow gown to unfold with inside of gown toward you.
3.Insert arms into sleeves.
4.Do not allow hands to protrude through cuffs.
5.Assistant fastens gown at neckline.
6.With dominant hand remaining inside sleeve, pick up glove for nondominant hand.
7.Insert nondominant hand into glove.
8.Stretch cuff of glove over cuff of gown.
9.With nondominant hand, pick up second glove.
10.Stretch cuff of glove over cuff of gown.
11.Closed gloving is complete.
12.Separate waist tie from gown and pass tie with tab to assistant.
13.Turn in a circle to wrap tie around your waist.
14.A sharp tug on tie will separate it from the contaminated tab, allowing you to fasten the tie without contaminating gown.
65
Open Gloving Technique
1.Perform hand hygiene. Obtain gloves, and check for correct size.
2.Open outer wrap to remove folded inner wrap.
3.Expose gloves with open ends facing you.
4.Open inner wrap completely, taking care not to contaminate gloves or wrap immediately surrounding gloves.
5.With one hand, grip cuff fold of glove for opposite hand.
6.Put on first glove, touching only inner surface of folded cuff.
7.Using gloved hand, grasp second glove under cuff.
8.Insert hand into second glove.
9.Put on second glove, and unfold cuff.
10.Insert fingers under cuff of first glove, and unfold cuff.
11.Gloving complete. Keep hands in front of body
and at safe distance from uniform to avoid contamination.
66
Wound Dressings: Dressing Removal
•Perform hand hygiene and don gloves.
•Inform the patient of what you are about to do.
•Use care in removing the dressing to prevent cross-contaminating the wound and yourself.
•Remove the dressing gently to avoid hurting the patient.
•Place the soiled dressing in a plastic bag and seal it before adding it to the biohazard container.
•Remove your gloves following the same procedure used with isolation techniques.
•Perform hand hygiene.
67
Applying a Sterile Dressing
•Prepare supplies:
➢Sterile gloves
➢Sterile drape
➢Sterile gauze
➢Tape
➢Normal saline
1.Tell the patient what you plan to do.
2.Perform hand hygiene.
3.Tear several strips of tape to a convenient length.
4.Open the sterile drape pack, placing the drape near the patient.
5.Partially open the drape by pulling from the corners. This creates a small sterile field for your other sterile items.
6.Open the dressing package and add the sterile dressing to your sterile field.
7.If you will need to cleanse around the wound, drop sterile gauze sponges into your field for this purpose.
8.To moisten the gauze sponges, open a small vial of sterile normal saline solution. Recheck the label and pour a small amount of the saline over the sponges. Do not allow liquid to soak through to the sterile towel. Check the label for the third time before discarding the vial.
9.Don sterile gloves using the open method described for sterile gloving.
10.Use the moist sponges to clean gently around the wound.
11.Allow the area to dry completely.
12.Apply the dressing over the wound, and secure it in place with tape.
13.Cover the patient.
14.Dispose of any waste.
15.Remove your gloves.
16.Perform hand hygiene.
68
Bacteria
• Have a cell wall
• Grow independently & replicate without a host cell
• Different characteristics
• Shape
• Gram (+) or (-)
• Acid-fast or Nonacid-fast
• Adapt to new conditions & mutate to resist and survive medical treatment
69
Viruses
• Smallest known disease-causing organisms
• Can not survive independently
• Uses host cell to form additional virus particles
• Mutate rapidly and become resistant to medications
70
Fungi
• Can be single or multicellular
• Many varieties
• Some are beneficial
• Some destructive
• May cause opportunistic infections when host is immunocompromised
71
Prions
• Lots of unknowns
• Discovered in 1983
• Possibly infectious proteins
• No DNA or RNA
• Transform healthy proteins in nerve cells into more prions!
• Resistant to body’s defense system
• Can multiply unchecked & cause irreversible damage
•Not curable
72
Protozoa
• Free-living, single cell animals
• Some are parasitic & live within the body
• Classification based on motility
• Some can survive outside the host
• Some can live between human body & insect vector
73
Pathogenic Organisms
microorganisms that cause disease
74
Susceptible host
for us it’s a patient who has reduced natural resistance to infection
75
Counters & Surfaces:
• Dilute bleach or germicide
• Surfaces must remain wet for minimum time stated
76
Mobile X-ray
• Wipe down before entering highly-susceptible patient area
77
Aprons & Gloves
• Clean weekly with disinfectant/ dilute bleach
• Clean if soiled
78
X-ray Room
• Wipe down table & tube
• Change pillow cases & sheet
79
Hand Hygiene
Hand washing:
• Visibly dirty
• Contaminated
• Before & after eating & restroom
• Possible contact exposure
Alcohol rub:
• In between patients
• After contact with inanimate objects
• Donning/doffing gloves
• Isolation areas
80
Standard Precautions
-Hand Hygiene
-Gloves
-Mask, Eye Protection, Face Shield
-Gown
-Respiratory Hygiene/Cough Etiquette
-Patient Placement
-Needles & Other Sharps
-Patient-Care Equipment
-Environmental Control
-Linen
-Safe Injection Practices
-Infection Control for LPs
-Medical Asepsis
81
Airborne Diseases and Precautions
-Airborne Diseases:
• Measles
• Varicella
• Tuberculosis
• SARS
-Precautions:
• N95 mask, particulate respirator
• Must be fit tested
-Designed to reduce the risk of transmitting dust particles containing the infectious organisms or ariborne droplet nuclei to a susceptible person
82
Droplet Diseases and Precautions
-Bacterial:
• Pneumonia
• Diptheria (pharyngeal)
• Pneumonic plague
• Pertussis
-Viral:
• Influenza
• Rubella
• Mumps
• SARS
-Precautions:
• Surgical mask when within 3 feet
-Designed to reduce the contact of large-particle droplets with the conjunctivae or with mucous membranes of the nose and mouth of a susceptible person
83
Contact Diseases and Precautions
-Enteric:
• C. diff, E. coli
-Respiratory:
• Parainfluenza
-Skin:
• Herpes simplex virus
• Scabies
• Varicella zoster
• Viral hemorrhagic infections
-Precautions:
• Gown
• Gloves
-Used to prevent transmission of diseases such as multidrug-resitant wound infections
84
Virulence factors
-Factors that enable bacteria to destroy or damage host cells and resist destruction by the host’s cellular defenses
-Properties of pathogens that distinguish them from normal flora
85
Can normal flora cause disease?
Yes if located outside their usual environment or when host’s immune system is compromised
