Hospital-Associated Infections Flashcards
What are HAIs?
Infections that patients get while receiving treatment for medical or surgical conditions, many preventable
What are examples of places to acquire a healthcare associated infection?
Acute care hospitals, GPs, ambulances, dialysis, outpatient, long term care, hospice
What is a CLABSI?
A central line-associated bloodstream infection, serious, pathogens enter bloodstream through central line
What is an MRSA?
Methicillin-resistant Staphylococcus aureus, bacteria resistant to many antibiotics, causes life-threatening bloodstream infections, pneumonia and surgical site infections
What are some risk factors for HAIs?
Crowding, antibiotic use, medical procedures, patient characteristics (gender, age, genetics), length of stay, behaviour of healthcare staff, healthcare facility
What are the 6 links in the chain of infection?
- Infectious agent or germ
- Reservoir
- Portal of exit
- Mode of transmission
- Portal of entry
- Susceptible host
What is a reservoir?
The habitat that the pathogen or germ grows, multiplies, and lives.
What is a human reservoir?
Human to human, no intermediate
What is an animal reservoir?
Pathogens in animals (e.g. COVID)
What are examples of environmental reservoirs?
Plants, soil, water
What is a the portal of exit?
The path by which a pathogen leaves its reservoir/host (e.g. influenza - respiratory tract in cough)
What are the two examples of modes of transmission?
- Direct transmission
- Indirect transmission
What are the two examples of direct transmission?
- Direct contact (skin to skin, kissing, intercourse)
- Droplet spread (spray, aerosols, coughing, talking)
What are the three examples of indirect transmission?
- Suspended air particles (airborne indirect transmission, dust or droplet nuclei)
- Inanimate objects (vehicle borne indirect transmission)
- Animate intermediates (vector borne indirect transmission)
What are the two examples of animate intermediates?
- Mechanical (e.g. rats)
- Biological - when pathogen reproduces within biological intermediate (e.g. mosquitos, ticks)
What is the portal of entry?
Access to tissues for pathogen to multiple (skin, mucus membranes, fecal oral, blood)
What factors affect host susceptibility?
- Genetic/constitutional factors
- Specific immunity (infection, vaccine, transplacental)
- Non-specific immunity
What are examples of non-specific immunity for susceptible host?
- Skin, mucous membranes, gastric acidity, cilia in respiratory tract, cough reflex
- Acquired - malnutrition, alcoholism, disease, therapy
What is herd immunity?
Resistance to spread of infectious disease within a population based on pre-existing immunity of high proportion of individuals as result of previous infection or vaccination.
What is septic shock?
Sepsis - body’s extreme reaction to infection
shock - imbalance in supply and demand
What are the three steps in septic shock?
- Blood pressure drops
- Tachycardia (increase in heart rate)
- Respiratory rate goes up
What are the four mechanisms of antibiotic resistance?
- Altered target site
- Decreased drug accumulation
- Altered metabolism profile
- Inactivation of antibiotic
What does the altered target site involve?
Change in structure of site the antibiotic inhibits
What does decreased drug accumulation involve?
Pump out antibiotic/reduced penetration
What does altered metabolism profile involve?
Different enzyme/pathway/decreasing steps
What does inactivation of antibiotic involve?
Enzymatic degradation
What is the betalactam mechanism?
Betalactam binds to the cell wall and inhibits cell wall synthesis, ruining cell wall integrity
What is beta lactamase?
An enzyme that bacteria has evolved which can break down the betalactam ring in antibiotics, inactivating it
How can beta lactamase be prevented?
Using beta lactamase inhibitors (like Co amoxiclav = amoxicillin + clavulanic acid) with antibiotics
What are the 5 moments of hand hygiene?
- Before touching patient
- Before a clean/aseptic technique
- After body fluid exposure
- After touching a patient
- After touching a patient’s surroundings
What is Candour?
Legal duty to be open and honest with patients, or families when something goes wrong that appears to have caused or could lead to significant harm in the future
