Lecture 2: Infection Control & Medical Asepsis Flashcards
Normal Flora
This is my home. I don’t usually cause trouble HERE, I often have weapons to protect my home, and the other residents keep me under control if I might get hostile
Pathogen
infectious agent (either virus or bacteria) -overwhelms infected host's defences causing illness
Nosocomial infections
HAIs health care associated infections
- Normal flora go where they shouldn’t
- Normal balance is compromised
- Pathogens from elsewhere are introduced (MRSA, VRE)
A-sepsis
without or freedom from disease causing microorganisms
A-septic technique
decreasing the chance of transferring microorganisms from one place to another
what are the a-septic techniques
-Clean technique (trying not to touch things)
-Medical asepsis- Clean technique
-Surgical asepsis – Sterile technique
(washing hands, gloves, sanitizer, ppe)
Colonization
Strain of microorganism becomes resident flora
- Grow and multiply but do not create illness
- Infection can occur when the organism succeeds in overcoming the hosts defense mechanism
Asymptomatic/subclinical infections
- No clinical evidence of disease
- Localized cell damage/infection
local infection
- Limited to a specific part of the body
- Generally easier to treat
Systemic infection
-Infection has spread from the site of origin and affects more systems
Bactermia
bacteria in the blood
Septicemia
Bacteremia results in systemic symptoms
explain the pathology of infection
1)Infection enters host
2)Moves to preferred target site
3)Overcomes host defences
due to:
-highly virulent microbe
-High microbial load
-Defenses are weakened
what components are involved with chain of infection
infectious agent susceptible host portal of entry mode of transmission portal of exit reservoir
what strategies are used to break the chain of infection for health care associated infections?
1) routine practices/ precautions
2) isolation precautions
chain of infection :
Etiological Agent
- what factors are associated
- Number (load, dose) – must be high
- Virulence
- Pathogenicity
- Ability to enter
- Susceptibility of host
- Ability to live and grow in host
etiological agents include..?
virus
bacteria
how do we protect ourselves from etiological agents
- Correctly cleaning, disinfecting, or sterilizing articles
- Educating clients and support persons
define: reservoir
The source, where microbe hangs out, causing illness or not
reservoir examples
- Other people (most common)
- Animals
- Self
- Plants
- Food
- Contaminated objects
reservoir: Respiratory tract
- what is the portal of exit?
Nose or mouth through sneezing, coughing, breathing or talking, endotracheal tubes or tracheostomies
reservoir: GI tract
- what is the portal of exit?
Mouth- saliva, vomiting
Anus- feces
Ostomies, drainage tubes
reservoir: reproductive tract
- what is the portal of exit?
Vaginal – vaginal discharge
Urinary meatus- semen, urine
Urethral discharge, contaminated urine
reservoir: blood
- what is the portal of exit?
Open wound, needle puncture, any disruption intact skin or mucous membrane surfaces
reservoir: tissue
- what is the portal of exit?
Drainage from wound or cut
what precautions are used to protect ourselves from microorganisms in reservoirs?
- Disposing of feces and urine appropriately
- Covering or capping all fluid containers
- Emptying suction and drainage bottles before full or according to agency policy
portal of exit
in order to infect more hosts, microorganism must leave it’s reservoir
possible portals of exit
Mouth, nose, Anus Urethral meatus Ostomies Drainage from wound Tubes and trachs Drainage tubes Open wound Break in skin or mucous membrane
what precautions are in place to avoid microbial transmission from portals of exit?
- Avoid talking, coughing, or sneezing over open wounds or sterile fields
- Cover the mouth and nose when coughing or sneezing
- Reservoir actions too
define: transmission
How microbes get to a receptive portal of entry of a susceptible host
what are the 6 routes of transmission?
Direct Indirect Droplet (sneeze) Airborne (TB) Vehicle borne (kleenex and dressings) Vector borne (bugs, animals)
Direct contact transmission
Just as the name sounds – requires direct transfer from person to person
Indirect contact transmission
Passive transfer from reservoir to intermediate inanimate object then to recipient
(sneeze on hand, touch door knob, another person touch knob then their nose)
Droplet transmission
- type of direct contact
- Large drops of respiratory secretions from coughing, sneezing, talking, singing, or when we suction patients
- Projected a short distance
airborne transmission
-particles are small
5 microns compared to 20 microns (droplet)
Remain in the air for a long time
ex) TB
-Particles are transmitted by air currents to a suitable portal of entry i.e. respiratory tract
Vehicle-borne transmission
- Any substance that serves as a means of transportation between infected host and the new host
- Fomites- inanimate materials or objects- including utensils, cups, soiled clothing, toys
- Water, food, milk, blood, serum and plasma
Vector-borne transmission
Animal or insect that serves as an intermediate means of transporting the infectious agent
-Salivary fluid is injected during biting or when feces or other materials are deposited into the skin through a bite or open wound
how do we protect ourselves from transmission?
- Teach appropriate hand hygiene
- Use proper antiseptics and disinfectants
- Wear gloves, gowns, masks and eye protection when necessary (PPE)
- Discard soiled materials appropriately
- Dispose of urine and feces appropriately
portal of entry
How the microorganism enters the host’s body
what are examples of portals of entry
- Break in skin or m membrane
- Mm of the eyes
- Respiratory tract
- Gi tract
- Blood stream
how do we protect ourselves against portal of entry
- Use sterile technique for invasive procedures and exposing open wounds
- Use puncture-resistant containers for used needles and syringes
- Provide clients with own personal care items
- PPE
susceptible hosts
Person at risk for infections
what factors increase susceptibility for infection?
1)Age –> very young and elderly (weaker immune systems)
2)Immune status (presence of antibodies)
3)Heredity
4)Physical and emotional stressors–> raises cortisol in the blood, decreasing immune and inflammatory response
5) Nutritional status
6) Medical therapies–> meds can increase risk of infection (antibiotics may kill off good bacteria), treatments (radiation), surgery
Medications
Obesity
Smoking
how do we decrease a person’s susceptibility?
- Maintain integrity of skin and mucous membranes
- Ensure client receives a balanced diet
- Educate public about importance of immunizations
- Educate about increased risks
routine precautions (standard universal)
- used with all clients
- all interventions that break chain of infection
- *hand hygiene, PPE (gloves, gown, masks, goggles)
- isolation precautions
- clean equipment, environment
- control source of infection
- educate
additional precautions
Used in addition to Routine Practices for patients with known or suspected infections that are spread by:
- airborne, droplet, contact transmission
- *special precautions used for drug resistant and emerging pathogens (C diff, MRSA, VRE, norovirus)
droplet precautions used for:
Influenza, Invasive Group A strep, MRSA, Meningitis, Pertussis, Respiratory infection of unknown origin, Rubella
contact precautions used for:
Clostridium difficile, ESBL, Gastroenteric illness of unknown origin, vomiting, diarrhea, impetigo, head lice, scabies
airborne and contact precautions used for:
Chickenpox, Disseminated Shingles, Measles (Rubella), TB (pulmonary)
special precautions used for:
VRE
What do you do if you are exposed to a blood borne pathogen?
- Report the incident immediately
- Needle stick injury
- Complete injury report
- Seek appropriate evaluation and follow-up
if you are punctured or lacerated by a utensil…
Encourage bleeding
Clean the area with soap and water
Initiate first aid
Seek treatment if indicated
mucous membrane exposure
Eyes, nose, mouth
Flush with saline solution or water
Flush for 5 to 10 minutes
how can you help susceptible hosts protect themselves?
Help patients perform good hygiene -Hand washing -Peri-care Ensure balanced nutrition with adequate hydration Mitigate stress -Coping mechanisms Ensuring adequate tissue oxygenation Glycemic controls Encourage immunizations Activate immunity (produce antibodies)
natural active immunity
Antibodies are formed in presence of active infection in the body
-lifelong
Artificial active immunity
Antigens administered to stimulate antibody formation
-lasts for years but is reinforced by booster vacines
passive immunity
Host receives natural or artificial antibodies produced from another source
Natural passive immunity
- Antibodies transferred naturally from an immune mother to baby through the placenta or in colostrums
- last 6 months to 1 year
Artificial passive immunity
- Occurs when immune serum (antibody) from an animal or another human is injected
- lasts 2 - 3 weeks
what are the risks for Nosocomial infections?
Diagnostic or therapeutic procedures.
Compromised host
Insufficient hand hygiene
