Infections Flashcards
what is antibiotic resistance
microorganisms change in ways which render medications ineffective
how do resistant genes comes about
intrinsic or acquired via mutation or acquisition of new DNA
mechanism of antibiotic resistance
- altered target sites
- enzymatic inactivation
beta-lactamases are enzymes which inactivate beta-lactam, the key structure in abx
they keep changing
creation of extended spectrum beta-lactamase infections (ESBL_
creation of carbapenemase which hydrolyses carbapenems [which ESBL cannot do]
HUGE PUBLIC HEALTH THREAT - decreased uptake
what is resistance vs clinical resistance
resistance =
based on quantitative testing of bacterial suspensions of bacterial agents to give concentration and minimum inhibitory concentration
clinical resistance =
when infection is highly unlikely to respond to even max dose abx
what are red flags when pt presents with an infection
difficulty breathing/swallowing
trismus
loss of lower border of mandible
submandibular swelling
voice changes, hoarse
drooling
lifting of tongue
eye closure
what is Ludwigs angina
bilateral infection of submandibular and sublingual space
life threatening cellulitis of soft tissue in FOM + neck
anaerobic gram negative P.intermedia, staph/strep
tx = I+D, cultures, IV abx
what is SIRS
systemic inflammatory response syndrome
life threatening organ dysfunction caused by dysregulated host response to infection
parameters of SIRS
<36* OR >38*
pulse >90/min
resp rate >20/min
WCC <4 OR >12
management of SIRS
immediate action
quicker abx, improves survival
high flow O2
blood cultures
IV abx
fluid challenge
measure lactate
measure urine output
WITHIN 1ST HOUR, SEPSIS 6
what is antimicrobial stewardship
organisational healthcare-wide approach to promote + monitor judicious use of antimicrobials to preserve future effectiveness
coherent set of actions which promote responsible antimicrobial use
in regards to stewardship, how do you decide on pen v vs amoxicillin
limit unintended consequences
pen v is active against most strep+gram negative, and has a smaller spectrum
amoxicillin is wider spectrum and has greater impact on selection of resistance on host microflora
USE SMALLEST SPECTRUM WHEN POSSIBLE
what are fascial spaces
potential spaces between fascia which is normally filled with loose connective tissue or “closed”
in which infection can spread superficially to deep planes
primary maxillary spaces
canine space
buccal space
infratemporal space
palatal space
sinus
pharyngeal, lateral pharyngeal, retropharyngeal,
primary mandibular spaces
buccal space
submental space
submandibular space
sublingual space
lateral pharyngeal
pterygomandibular
which space do lower tooth infections generally go
what is the exception
lingually - perforating above mylohyoid attachment into the sublingual space/buccal
lower 8’s - perforating below mylohyoid attachment, into submandibular space [problematic], submasseteric -> pterygomandibular -> lateral pharyngeal
maxillary anterior vs molar teeth spread
anterior = canine
molars = buccal->infra temporal->palatal
what is the difference between below + above muscle insertions in maxillary
below - buccal spread
above - into soft tissue, infraorbital swelling, partial eye closure, lose nasiolabial spread [canine]
mandibular anterior vs molar spread
anterior = stay, mental/submental
pre/molars = buccal -> submasseteric -> sublingual -> submandibular -> lateral pharyngeal
how would you manage facial swellings
establish drainage
remove source of infection
abx - if systemic, look for SIRS, urgent referral if yes
e.g. submandibular
- GA?, IV abx, drainage
- be aware of facial nerve
- rule = 2 finger breadths below lower border of mandible
-hilton technique = 2-ended instrument, close and place in excision, open inside, allows bursting and drainage and ensures no blood vessel/nerve is damaged
- place E/O drain, suture, leave for few days
