Intro Flashcards
Presentation:
BP 80/60
Temperature 39 degrees
HR 120/min
This presentation is signs of ______→ can lead to ______
Bacteria that are responsible for this presentation: typically ______ bugs eg. klebsiella pneumonia & ecoli
Bacteria component that is responsible: ______
This presentation is signs of septic shock → can lead to death
Bacteria that are responsible for this presentation: typically gram -ve bugs eg. klebsiella pneumonia & ecoli
Bacteria component that is responsible: Lipopolysaccharide
What is a biofilm
Biofilm is produced by bacteria as a protective mechanism; a layer of slime that protects bacteria so that they are not killed by the immune system.
what is the impact of biofilm on patient treatment
When the bacteria reach a certain concentration → can lead to infections
Culture: to ____ an organism
Eg. :
grow
Aerobic culture
Anaerobic culture
Fungal culture
Viral culture
Serology: To detect the ____ present following exposure to the organism
Eg.
antibodies
Eg. Blood test
Microscopy: to _____
Eg.
visualise the organism
Gram stain Fungal microscopy Acid-fast stain Immuno-fluorescence Parasitology aka OCP
Molecular testing: to _______
Mostly for detecting ____ or pathogens that cannot be ____.
Or when you need an answer ____.
Eg
detect nucleic acids
Mostly for detecting viruses or
Pathogens that cannot be cultured
You need an answer FAST
Eg. PCR
Sterile vs non sterile sites
Sterile: “inside” body
Eg. blood, CBF, vitreous fluid, joint
Non-sterile: “outside”
Eg. skin, drains, anus, intestines, respiratory organs, stomach, etc
Examples of wound swabs in infection
Staphylococcus aureus, group A streptococcus
Examples of urine culture in colonization
Bacteria growth from indwelling catheters
Examples of urine culture in infection
E coli, klebsielle pneumoniae (pure & high viable count with clinical signs)
The 5 moments of hand hygiene
- Before patient contact
- Before aseptic task
- After body fluid exposure risk
- After patient contact
- After contact with patient surrounding
Swab: avoid swabbing an area that is ______
completely dry
A more representative sample is a swab taken before/during/after wound cleansing
AFTER
Screening swabs generally detect only a SPECIFIC organism eg. ____
MRSA
Rayon bud (Tip) is for identifying
bacteria
Aerobic culture
Anaerobic culture
MRSA screen
Gram-stain
They suit what kind of swab?
Rayon bud (Tip)
Rayon bud (Tip) is not suitable for
Viral PCR
Viral culture
Labels found in Rayon bud (Tip)
‘Aerobes and anaerobes’
Swab in UTM/VTM is for
Viral & PCR testing
Viral culture
Viral antigen
Viral PCR (eg. influenza)
Chlamydial PCR
They suit what kind of swab?
Swab in UTM/VTM
Swab in UTM/VTM is not suitable for
Aerobic & anaerobic culture
Label found in swabs in UTM/VTM
‘UTM-RT’
eSwab media is used for
better detection of bacteria compared to Rayon bud
Aerobic culture
Anaerobic culture
Bacterial PCR
They suit what kind of swab?
eSwab media
eSwab media is not suitable for
viral testing
What is the default urine sample to send? And why?
Mid-stream urine.
Because urethra is a non-sterile site
Best method as the 1st bit of urine that pass may be contaiminated with bacteria from skin (reduce contamination from urethra & perineal region)
In-out catheter urine: if required, clamp the tubing ______ to the sampling port
a few cm distal
In-out catheter urine—
Best way to get good quality urine sample: sample from the ______ (______)
sample from the sampling port (needle-less)
Good specimens of culture: low/high viable count
high
Disadvantages of long term urinary catheter
- ↑ risk of UTI (esp elderly)
- ↑ risk of getting infection caused than > 1 bug
- Colonization of the catheter with various organisms
- Patients will almost always have +ve urine cultures
Collect sputum in the _____ to avoid _______ with food particles
morning; contamination
Broncho-alveolar lavage is only used in ____, for ____ patients
ICU; sedated
Presence of epithelial cells in a respiratory sample = specimen from upper respiratory tract which means
POOR QUALITY SAMPLE as it is highly contaminated with other flora
What is a BAL sample?
How is it obtained?
It helps diagnose and treat certain lung diseases.
Collected by washing the airways with a saline solution and capturing fluid during the process.
What is a ETT sample?
How is it obtained?
A flexible plastic tube is placed through the nose or mouth into the trachea, or windpipe, to help a patient breathe.
Can be obtained from instinctively ventilated covid patients through catheter from an endotracheal tube or from tracheotomised patients by directly tracheal suction
Effect of endotoxin found in gram -ve bacteria
- Endotoxin are chemicals (found in cell wall of gram -ve bacteria) that can cause body reaction
- Even when the bacteria is dead (correct antibiotic is given), this chemical will still be released into the bloodstream and tissues
- It initiates a host inflammatory response which contributes to the severity of symptoms during infection (Eg. fever, septic shock)
- Effects: histamine release, WBCs release and vessel dilation
- Vessels dilate (blood supply to organs are compromised, blood pressure drops) capillaries become permeable, fluid leaks out
- Can affect clotting system (thrombin formation) → blocked blood vessels
- Can cause: sepsis → organ failure
- Must be treated early
What is commensal bacteria? Are they usually harmful?
- bacteria that are normally found on the human body
- usually not harmful
- may contribute beneficial effects
Colonization increases in these type of patients:
- Hospitalised patients
- Patients with medical conditions
- Patients given antibiotics
Lipopolysaccharide is found within ____.
Ability:
- Found within the cell wall
- Ability to produce antibiotics → hypotensive, tachycardic & pyrexic
Where do you find biofilms?
ETT tubes, urine catheters
