EBM Session 5 Flashcards
what is Septra/Bactrim?
TMP/SMX
trimethoprim and sulfamethoxazole
What is the moa of trimethoprim?
Inhibits dihydrofolate reductase to impair DNA.
What is the moa of sulfamethoxazole?
Structurally similar to PABA and so blocks DHF synthesis inhibiting DNA synthesis.
Often paired with Trimethoprim to create septra/bactrim.
What is the spectrum of activity for bactrim/septra?
TMP/SMX is best used for community aquired MSSA and has no coverage against anaerobes.
What is the dosage for bactrim?
2 tablets 80mg TMP/400mg SMX q 12 h
When is bactrim use contraindicated?
Increased drug levels of:
Coumadin and sulfonureas.
Also cleared renally/hepatically.
what is cubicin and what is its moa?
Cubicin is Daptomycin
It works by depolarizing cell membranes.
What is the indication for cubicin use?
Daptomycin use indicated in hospital aquired MRSA and MSSA.
Also hits enterococcus.
What is the dosage for cubicin?
IV injection over 2 mins or infusion over 30
4mg/kg q 24h for 7-14 days.
What is the moa of tygacil/tigecycline?
Inhibits protein translation by binding to the 30s subunit.
What is the indication for tygacil use?
MRSA and MSSA used for extreme cases in which there is a mixed infection or sepsis!!!!
What is the dosage for tygacil?
100 mg; 50 mg q 12h over 30-60 minutes.
Has extreme side effect of death.
What are the golden rules of surgical prophylaxis?
The drug should reach maximum levels at the time of the incision.
the abx should be directed against the most commonly found organism.
Which wound types demand prophylaxis?
Bites!
research has found that punctures and lacerations do not require prophylaxis unless signs of infection begin.
Which prophylaxis should be used if MRSA/MRSE is expected?
Vancomycin
1g 1 hour before surgery followed by 1g 12 hours following the first dose post op./
When would clindamycin prophylaxis be utilized?
Penicillin allergies or in the case of implantation.
600-900 mg IV is used.
What is the general consensus with surgical prophylaxis?
Some believe it must always be performed.
Other studies have shown that it does not decrease risk of infection at all.
How will synovial fluid analysis change with an infection?
Increased cell count normal 0-3000 with infection can get as high as 100,000
What is the most common infectious agent in acute hematogenous osteomyelitis?
Staph aureus!
GBS in neonates 0-3 months
H. influenzae in children under 2 years
Pseudomonas in drug user
Salmonella in sickle cell patients!
What ESR in children notates acute hematogenous osteomyelitis?
ESR >20 mm/h
or WBC >12,000
Realise that radiographs will lag behind by a week.
What are the best imaging modalities for acute hematogenous myelitis?
Bone scan for early cases.
MRI is the best non-invasive study when used without contrast. Will be looking for decreased T1 signal.
bone biopsy and bone culture is the gold standard here.
What is the treatment for hematogenous osteomyelitis in adults?
Vancomycin 15-20mg/kg/dose q8 to 12h
If IV drug user want to cover pseudomonas
What is the treatment of choice in adults that have osteomyelitis but also have sickle cell anemia?
This requires cipro to cover S. aureus and salmonella.
Ciprofloxacin 750 mg PO or 400 mg IV q 12 hours.
What antibiotic coverage should be used in children over 3 months old vs under 3 months with acute hematogenous osteomyelitis?
IV nafcillin/oxacillin clindamycin or vancomycin if over 3 months old.
Target group B strep if under 3 months and use cephtriaxone IV combined with vancomycin or nafcillin/oxacillin.
