Lower Respiratory Tract Infections - Hospital Acquired Pneumonia/Ventilator-Associated Pneumonia Flashcards
Definition of HAP
Pneumonia occurring 48 hours or more after hospital admission
Definition of VAP
Pneumonia occurring 48 hours or more after endotracheal intubation
What kind of bacteria typically colonize in HAP?
-Usually colonized with aerobic gram-positive bacteria
-After 3-5 days of hospitalization, converts to gram-negative organisms
Why does VAP occur so often in ventilated patients?
Endotracheal tube bypasses all host defenses and decreases LRT defenses
Risk factors for HAP/VAP
-Advanced age
-Severity of comorbid diseases
-Duration of hospitalization
-Endotracheal intubation
-Nasogastric tube
-Altered mental status
-Surgery
-Previous antimicrobial therapy
Typical presentation of HAP/VAP
-New lung infiltrate +
-New onset fever
-Purulent sputum
-Leukocytosis
-Decline in oxygenation
Common pathogens present in HAP/VAP
-Pseudomonas aeruginosa
-Enteric gram-negative bacilli
-Acinetobacter baumannii
-Staph aureus (MRSA greater concern in this population)
What is more likely to infect HAP/VAP, gram-negative or gram-positive?
-Aerobic gram-negative bacilli (70%)
-Staph aureus (20-30%)
Which cultures should be obtained in all HAP/VAP patients?
-Respiratory cultures
-Blood cultures
Would you want to obtain an invasive or non-invasive respiratory culture?
Non-invasive is better
Risk factors for multi-drug resistant HAP
Prior IV antibiotic use within 90 days
Risk factors for multi-drug resistant VAP
-Prior IV antibiotic use within 90 days
-Septic shock at time of diagnosis
-Acute respiratory distress syndrome prior to diagnosis
-Acute renal replacement therapy prior to VAP
-5 days or more of hospitalization prior to diagnosis
Risk factors for MRSA in HAP/VAP
-Typical risk factors for MRSA
-Prior IV antibiotic use within 90 days
-ICUs where > 10-20% MRSA isolates
-Treatment where prevalence is unknown
Risk factors for MDR pseudomonas in HAP/VAP
-Prior IV antibiotic use within 90 days (carbapenems, broad-spectrum beta-lactams, FQs)
-ICUs where >10% of isolates resistant
-Treatment where resistance rates are unknown
What is the goal of empiric therapy in HAP/VAP?
-Provide broad spectrum antibiotics while avoiding unnecessary harms of inappropriate coverage
-Empiric regimens should be based on local distribution of pathogens and susceptibility and if possible, should stratify for populations such as VAP or ICU populations
Empiric antibiotic therapy for HAP/VAP specifically for MRSA coverage
-Vancomycin
-Linezolid
Empiric antibiotic therapy for HAP/VAP specifically for pseudomonas coverage
-Zosyn
-Cefepime
-Imipenem
-Meropenem
-Levofloxacin
Empiric antibiotic therapy for HAP in patients who ARE NOT at high risk for mortality (not on ventilator support or septic shock)
-Zosyn
-Cefepime
-Imipenem
-Meropenem
-Levofloxacin
Empiric antibiotic therapy for HAP in patients who ARE at high risk for mortality (not on ventilator support or septic shock) and MRSA risk
Beta-lactam (Zosyn, cefepime, imipenem, meropenem) + non-beta-lactam (levofloxacin, tobramycin/amikacin) + MRSA coverage
Empiric antibiotic therapy for VAP
Beta-lactam (Zosyn, cefepime, imipenem, meropenem) + non-beta-lactam (levofloxacin, tobramycin/amikacin) + MRSA coverage
When would you use daptomycin in LRTIs?
Never
When would you use polymyxin in LRTIs?
-Avoid empiric use if possible
-Reserve for patients with high prevalence of MDR pathogens
-Significant nephrotoxicity
When would you use aminoglycosides in LRTIs?
-Recommend against use as monotherapy
-Avoid empiric use unless necessary
-Poor lung penetration, nephrotoxicity, ototoxicity, reports of lower clinical response rates
When would you use tigecycline in LRTIs?
-Great for polymicrobial infections
-Associated with increased mortality
Duration for HAP/VAP therapy
Recommend 7 day duration if clinically stable
