Lower Respiratory Infections: Nosocomial Flashcards
What are the two types of nosocomial pneumonias?
HAP and VAP
What is the criteria for pneumonia to be HAP or VAP?
Must occur at least 48 hours after admission (thus it was not already present at admission), or after intubation (for VAP).
What’s the big deal about HAP and VAP?
They are the leading cause of mortality among hospitalized patients! Mortality is 15-50% depending on severity.
What are the common pathogens for HAP/VAP?
Mostly gram negative rods. (Psuedomonas, acinetobacter, Enteric g-‘s like e coli, klebsiella, enterbatcer, proteus, etc.)
Staph Aureus is also a concern 16% HAP, 25% VAP. methacillin resistant about half the time.
How do you diagnose HAP/VAP
Via clinical criteria alone. Procalcitonin and the CPIS score are not sensitive enough.
Should you aggressively search for offending pathogen in HAP/VAP?
Yes! Blood and sputum cultures for everyone! Resistant orgs are much more common than in CAP, and we need to have a way to de-escalate. Non-invasive cultures are preferred (sputum) over more invasive (BAL).
Who gets double antipseudomonal coverage in HAP?
- People who have have IV abx in prior 90 days
- People with structural lung disease (bronctiectasis or CF).
- Anyone at high mortality risk (on vent, septic shock)
Who needs MRSA coverage with HAP?
- IV abx in prior 90 days
- In treatment unit/hosp with MRSA prevalence > 20%
- Anyone at high mortality risk (on vent, septic shock)
Empiric Coverage for HAP (low-risk of mortality)
Single agent antipseudomonal +/- MRSA coverage
beta-lactam (cefepime, imipenem, merrem, zosyn) OR Levaquin/Cipro AND Vanc or Zyvox if MRSA > 20%
*beta-lactam could be aztreonam or even ceftaz, and FQ could be Cipro, if providing Vanc/Zyvox since MSSA coverage is there.
Empiric Coverage for HAP with High risk of mortality or high risk of MDR orgs?
Double antipsuedomonal coverage + MRSA coverage
Two of either: Beta-lactam (cefepime, imipenem, meropenem, zosyn, aztreonam) OR FQ (levaquin, cipro) OR AG (Amikacin, Gent, Tobra) PLUS Vanc/Zyvox
Considerations for Empiric Coverage for VAP?
If one of the following risk of MDR, double pseudomonas and MRSA coverage:
- IV abx in last 90 days
- septic shock
- ARDS preceding VAP
- 5 or more days in hospital prior to VAP
- Acute renal replacement prior to VAP
Regardless, if MRSA > 10-20%, cover, and if risk of resistant G- bacilli > 10% or unknown, double cover pseudomonas. If you can use an agent that is more than 90% active for all g- bacilli per antibiogram, you can use that single agent.
How does Empiric Coverage for VAP differ from HAP?
Polymyxins are an option for gram- coverage: Colistin or Polymyxin B. Otherwise it’s the same as HAP.
Can you use Aminoglycoside Monotherapy for pathogen directed therapy of HAP/VAP?
No! There risk of treatment failure and emergence of resistance.
Should you still use combination therapy for directed therapy against Pseudomonas?
If patient still in septic shock, yes, there is a mortality benefit. But once septic shock resolves, de-escalate to one active agent per C&S (just not AG monotherapy).
Which organism can be treated with the Sulbactam component of Unasyn?
Acinetobacter!
What about directed therapy against Acinetobacter?
Notoriously drug resistant. These are the preferred agents, if supported by C&S.
First - Carbapenem
Second - Unasyn (because of sulbactam)
Third - Polymyxin + adjunctive inhaled colistin
Can you use Daptomycin for MRSA pneumonia?
NO! The surfactant destroys the drug.
What about ESBL producing organisms?
Carbapenems are often the treatment of choice
What about Carbapenem resistant organisms?
Base it on C&S results: Polymyxins, inhaled colistin. Potential role for newer agents: - Cefolozane-tazobactam (Zerbaxa) - Ceftazidime-avibactam (Avicaz) - Meropenem-vaborbactam Zosyn may still retain activity, but questionable
What about Ceftolozane-tazobactam in HAP/VAP?
- Zerbaxa
- It’s a novel cephalosporin with beta-lactamase inhibitor.
- Active against most ESBL and AmpC producters
- Retains activity against many strains of carbapenem resistant P. aeruginosa.
- Does NOT have activity against carbapenemase producers.
- Does NOT have much G+ activity (no Staph activity)
- FDA approved for HAP/VAP in adults
- Reserve for when other therapies won’t work
What about Ceftazidime-Avibactam for HAP/VAP?
- Avicaz
- Novel beta-lactamase + ceftaz
- Retains activity against many MDR GNR, including ESBL, AmpC, and CRE (including KPC and OXA-48)
- FDA approved for HAP/VAP
What about Meropenem-vaborbactam for HAP/VAP?
- Vabomere
- Espeically useful for CRE (carbapenem enterbaceriaceae).
- Active against most ESBL, AmpC, and KPC-producting CRE (similar to Avicaz).
- No MRSA activity
- Does not inhibit OXA-48 enzymes.
Are PK/PD dose optimizations recommended by the guidelines?
Yes! Vanc/AG’s should be weight-based and utilize TDM. Beta-lactams should be administered via extended infusions.
What about inhaled abx for HAP/VAP?
Use for VAP due to MDR GNRs suscebtible only to AG’s or polymyxins.
