Chain of infection
Ability for micro organisum to spread if goes through chain. Must take interventions to break chain
Etilogical agent-> reservior-> portal of exit-> mode of transmission-> sucestible host
Infectious Agent
Pathogen that contains virulence, ability to cause infection ( etilogical agent)
Reservior
Endogenous and exogenous infections stem from reserviors
- Source of the pathogen , source of infection and where it thrives
- Endogenous infection: infection from within, body’s normal flora becomes overcome by opportunistic pathogens due to weakened host. ( ecoli, staphyloccous)
- Colonized bacteria causes infection ( no symptoms) but can cause infection ( symptoms, weak immunity) - infection due to these pathogens colonizing over normal flora
- Exogenous: sources from outside and does not exists in flora. Brought in via food, water, blood and can pass into body. As a virus, require living tissues to thrive and divide -COVID19, HIV , salmonella
Portal of exit
Leave reservoir via nose, mouth, vaginal, urethral, wounds, rectal, ways to leave the reservoir
Mode of transmission
Travel to host via direct ( skin to skin between susceptible host and infected person) indirect ( intermediate object carry infectious agent to host) via living and nonliving object
Portal of entry
Ways to enter host, wounds, oral, uretheal etc
Sucestible host
Weakend host, higher risk to exposure, virulence, suffcient number and enter of host.
- Increased risk , due to older/younger age, weak immunity , nutrient intake, poor health, illness, hospitalization- opportunsitic pathogens , stress and immune overload , medications and treatments
Nosomial infection
Infection acquired after hospitalization , HIA, acquired infection in hospital- iatrogenic illness due to exam that was not present upon admission
- Pathogen spread in hospitals, between patients, nurses. Treatments, providers, equiptment produce iatrogenic infections.
- Microbial resistance ( superbugs) MRA, C diff infections require routined resistance screening.
Cleaning
Medical aspetic technique of removal of substances, secretions, excetions, blood, microbes from surfaces.
Handwash, friction, sterilized objects and rinse.
Disinfection
Reduces and eleminates bacteria expect for spores- disinfecants, chemicals, heat, cleaner agents can be used, UV and heat.
- Used in PPE, soiled linen, ABHR
Sterlization
Destruction of all bacteria and spores, gas, pressure, steam and pressure instruments- cleaned, sterilized via pressure, gas agents.
Routine precautions
PPE worn include gloves, gown, mask or n95, and shield
- Designed for all regardless of infection risk, exposure to blood, emesis, sweat, gown, ,masks used to prevent exposure and transmission via fluids
- Done in all care regardless of diagnosis, fluid secretions, nonintact skin and to dispose linen/clean. * universal precautions to protect membranes and skin- PPE’s used as barrier protection
Second tier Isolation Precautions
- Contained pathogens within patient room with risk for infectious agent.
- Full isolation and protection
- Patients colonized and placed under full airbone, droplet, contact precautions
- Higher risk for contamaintion, in additon to usal routine practices.
Modes of transmission isolation
Direct ( direct with infected person)
Indirect ( contaminated object)
Airbone: microbes via airbone droplets, aerosols smaller as well. Measels, TB- full negative pressure room and isolation, contain aeresols and droplets. N95 to protect, private room
Droplet: microbes known to transmit via resp. droplets via cough, sneeze, talking and spread mircobes. Private room, mask, and 2mm distance.
Contact: infections due to direct/indirect , wound/skin infections. Skin or object spreads microbes. Gloves and gown, disinfection of surfaces
Mask donning and doffing
Ensure mask fits, never is reused, remains on during care, and use or handrub before and after.
- When maks becomes damaged and soiled, cannot prevent pathogen spread. Ensure extends above nose and at chin, replace and discard between care, when soiled, damp and clean hands after use.
- Clean hands prior to touching face
When should gloves be removed
Soiled, broken, damp, prior to care, during different activities, and once they have become contaminated.
Remove after care, and ensure hand hygine before replacing gloves, discard gloves. Replace when done, between patients.
Factors Increasing Risk for infection
- Diabetics ( WBC unable to destory bacteria)
- Family: genetics, lack of hygine knowledge, precautions, exposure to host, health promotion, caregiver faitgue
- Catheterization: Rubber catheter, external deviced, IV’s, promote biolfims ( collection of microbes that can enter patient, collection of pathogens , reserviors thus cause infection.
–> Become resistance, ensure cleaned prior to sterilized sat insertion sites. Biofilms can remain if secretions are not washed off, kills bacteria but must be cleaned prior. - Treatments: weak WBC, immune response thus lower defence
Impacts of HIA
- Inflammatory, painful response,
- ADL’s, caregiver roles, income, loss of employment, food
- Prolonged hospialization , use of resources harms population, expenses, delayed healing, isolation, and asymp. colonized patients can spread.
Breaking the chain
- PPE donning and doffing, protect patient, nurse, family
- Pandemic ( worldwide spread) epidemic occurs first - COVID19 spread resp. aerorels and droplets.
Vaccines to prevent illness
Donning
ABHR-
1. Gown ( protect from transmission, tied top down, front becomes dirty, avoid front)
2. Masks (prevent exposure of membranes, medical mask or n95 ( airbone, droplet precautions) - change when damp, broken, soiled)
3. Eye spray protection
4. Gloves for hand safety, change when soiled, damaged, between care activities
Doffing
Prevent contamination, most to least, dirty to cleanest order, hand hygine between steps
1. Gloves - hand hygine
2. Gown- hand hygine untie top-bottum and avoid touching outside
3. Eye mask- hand hygine
4. Mask- hand hygine
Patient isolation
- Risk for sensory depervation due to prolonged isolation, orient to person, place, time
- Meaningfull stimuli, music, belongings, reading
Secondary/teritary: asssess actual sensory status, tiem, touch, taste, stimulate senses
Social support: family involvement, validate feelings , goals, encouraged particpation of care
Assess services: collobration, pyschology, dietary needs, meaningful stimuli, personal objects. Planned activites, vists, call bell in reach
For depression, secondary prevention of symptoms, changes in mood, positive feedback and teritary includes assess harm, pt strengths , goals and rewards to achieve
Barrier precautions at home
Income, employment, food, housing, access to services all impact ability to manage barriers
- Isolation can result in economic burdens, caregiver roles, unemployment
- PPE education of family, provide emotional supports
- Poor PPE can reintroduce pathogens the patient who is already compromised, delay recovery
- Secondary prevention includes wearing PPE, vaccinations, hand hygine, understand how airbone, droplet, contact precautions spread
- Sensory depervation include assessing LxO, aXO, and bring in tv, music, family to engage with
Hand hygine steps
Before, during, after pt contact
Before and during clean (aspetic)
After contact, objects, exposure to linen, fluids, contamination, personal care.
