Pneumonia Flashcards
What are the differences between CAP, HAP, and VAP? What is their pathophysiology?
CAP: pneumonia in a patient not hospitalized or hospitalized for less than 48 hours
HAP: pneumonia > 48 hours after hospitalization
VAP: pneumoniae > 48 hours after endotracheal intubation
Pathogens gain access either through direct inoculation, aspiration of bacteria, hematogenous spread or inhalation of aerosolized pathogen
Untreated can lead to bacteremia, sepsis/septic shock, lung abscesses, empyema/parapneumonic effusion
Clinical presentation: high fever, chills, cough or sputum with phlegm, SOB, pleuritic chest pain
What are the common pathogens involved in CAP?
Outpatient: respiratory viruses, S./C./M. pneumoniae, M. catarrhalis, S. aureus, H. influenzae (think, normal respiratory flora or pathogens!)
Inpatient (non-ICU): Outpatient gram-negatives (M. catarrhalis, H. influenzae)
ICU: S. pneumoniae, S. aureus (+ MRSA), H. influenzae, Legionella spp., GM – bacilli (i.e., atypicals)
What are the common pathogens in HAP/VAP?
S. aureus (+ MRSA), Pseudomonas., Enteric GM- bacilli (Enterobacter spp.), S. pneumoniae
How do you diagnosis pneumonia?
CXR (can see infiltrates), CT (detailed images), MRI (less common), C+S (sputum and blood, usually reserved for severe CAP, HAP, and VAP)
What are the risk factors for pneumonia?
- Decreased respiratory transport, smoking
- Malnutrition, previous CAP
- Increased aspiration risk (stroke, Parkinson’s, decreased level of consciousness, alcohol use, BZDPs, APs)
- Very old or young patients, underlying disease, immunocompromised
What is the importance of treating pneumonia ASAP?
delay 8+ hours of therapy, bacteremia, severity
What are some causes of pneumonia?
- Drugs that may exacerbate: ACE, BBs, NSAIDs
- Pulmonary toxic drugs: bleomycin, MTX, phenytoin
- Sedatives, depressants may increase aspiration risk
- Cigarette smoke (impairs mucociliary and macrophage activity – can promote)
- Pneumonitis (inflammation that can present like pneumonia but self resolves)
What are some general treatment consideration when treating pneumonia?
General: use empiric therapy until C+S and always consider local resistance patterns! Then progress to targeted therapy (always, always, always).
- Symptoms usually improve after 3-5 days, but should treat patient for approximately 5-7 days (7-10 for HAP/VAP) (i.e., patient is stable for at least 72 hours)
Special: If the patient’s received antibiotics within the last three months, always give a different class of antibiotics to minimize AMR.
- Suspect MDR if: hospitalization 3+ days, ABX therapy within 3 months, higher frequency of resistance based on local antibiogram, immunocompromised or a nursing home resident
How do you treat outpatient CAP? (no modifying factors)
- Amoxicillin (kids and adults; consider HD) [GM+ coverage]
- Doxycycline 100mg PO BID [GM +/-, atypicals]
- Macrolide (azithro/clarithro) [GM+/-, atypicals]
How do you treat outpatient CAP? (with modifying factors)
- Beta-lactam (amoxi-clav) + macrolide/respiratory FQ [atypical coverage]
How do you treat inpatient CAP? (non-ICU)
- Respiratory FQ (Levo/Moxi) [GM+/-, atypicals)
- Beta-lactam (ceftriaxone, cefotaxime, or amoxi-clav) + macrolide (GM+/-, atypicals)
How do you treat inpatient CAP? (ICU)
Beta-lactam IV + FQ IV or AZITH IV
How do you treat inpatient CAP? (Pseudomonas suspected)
- Antipseudomonal beta-lactam (Pip-taz, cefepime, meropenem, meropenem, ceftaz) + (Cipro/Levo)
- Antipseudomonal beta-lactam + AG + AZITH
What is the targeted therapy for CAP if it’s S. pneumoniae?
(consider resistance): penicillin, amoxicillin (or amoxi-clav), 3GC
What is the targeted therapy for CAP if it’s H. influenzae?
amoxicillin, 2/3 GC, amoxi-clav
