Ch10: Lower Respiratory Flashcards
(202 cards)
pneumonia is infection of the….
lungs and bronchi
everyone with pneumonia also has….
bronchitis
but not everyone with bronchitis has pneumonia
most-likely causative pathogens in pneumonia depends on whether they have underlying conditions, including: (6)
- COPD
- diabetes
- heart failure
- liver disease
- CKD
- asplenia
- alcoholism
- malignancy
Most likely causative pathogens in someone with CAP without significant comorbidities (6)
BACTERIAL
- Strep pneumoniae (most common)
- M. pneumoniae (atypical)
- C. pneumoniae (atypical)
- Staph aureus
VIRAL
- influenza A or B
- respiratory synctial virus (RSV)
Most likely causative pathogens in someone with CAP and with significant comorbidities (6)
same as before, PLUS Haemophilus pneumoniae and legionella
- S. pneumoniae
- H. influenzae
- M. pneumoniae
- C. pneumoniae
- Staph aureus
- Legionella
- respiratory viruses (influenza A/B, RSV)
who is likely to have M. pneumoniae or C. pneumoniae pneumonia
atypical
largely cough-transmitted
often seen in groups of people who have recently spent extended time in close proximity (e.g., correctional facilities, college dormitories, long-term care facilities, small offices)
index patient 1 –> 3 weeks later, the rest of the group is sick with it
will cause a bilateral pneumonia
typical presentation of CAP caused by M. pneumoniae or C. pneumoniae
atypical
“walking pneumonia”
(most commonly from M. pneumoniae)
usually dry cough with less severe signs or symptoms
usually bacterial
how is legionella pneumonia transmitted
usually contracted by inhaling mist or aspirating liquid that comes from a water source contaminated with Legionella
No evidence for person-to-person spread
outbreaks occur when common source of contaminated water or air conditioning systems
major risk factors for severe legionella pneumonia disease
- older age
- male
- smoking
- diabetes
with these risk factors, may get very very ill and need ICU
who gets Staph Aureus pneumonia?
largely limited to post-influenza pneumonia
folks who were recently sick with flu
only see this pneumonia occurring after an influenza infection
staph aureus pneumonia
diagnostic evaluation for pneumonia
- CBC with diff
- BUN/Cre
- additional testing based on patient presentation and comorbidity
- chest xray
why do a CBC with diff in someone with pneumonia?
- see if WBCs are responding to infection
- those with anemia do worse than those without
why get BUN/Cre in someone with pneumonia?
- hydration status (BUN)
- those with kidney disease do worse than those without
recommended length of antibiotics for CAP
- minimum of 5 days
- needs to demonstrate evidence of increasing stability
- must be afebrile for 48-72 hrs before discontinuation
- average length = 5-7 days
Empiric antibiotic options for CAP WITHOUT comorbidities (3)
- doxycycline (best choice per Fitzgerald)
- macrolide (azithromycin, clarithromycin, erythromycin) if local resistance rates are low
- amoxicillin (high dose)
how to determine if azithromycin or other macrolide (e.g., clarithromycin, erythromycin) is a good prescription for someone with CAP?
take into consideration local Strep Pneumoniae macrolide resistance rates
if rate >20%, do not use
can be determined from local antibiogram, from public health department
best choice antibiotic for CAP without comorbidities
doxycycline (per Fitzgerald)
Empiric antibiotic options for CAP WITH comorbidities (3)
- respiratory fluoroquinolone (levofloxacin, moxifloxacin)
- doxycycline OR macrolide (azithromycin, clarithromycin) PLUS a beta-lactam such as amoxicillin-clavulanate, cefpodoxime, or cefuroxime
best choice antibiotic for CAP with comorbidities
respiratory fluoroquinolone
levofloxacin, moxifloxacin, gemifloxicin
what are the (3) respiratory fluoroquinolones
levofloxacin, moxifloxacin, gemifloxicin
significance of tachypnea in CAP
one of the most sensitive and specific findings for pneumonia, especially in children and the elderly
this may be a better sign in elderly than a fever (don’t always develop fever)
s/t impaired gas exchange, possibly due to fever
significance of crackles or rales on respiratory exam in CAP
occurs with sudden opening of distal fluid-filled airways
often demonstrate partial (not full) resolution with a cough
noted in pneumonia and heart failure, among others
crackling, clicking, rattling sound on inspiration
evidence of consolidation in CAP
- dullness to percussions (dense tissue when percussed sounds dull)
- increased tactile fremitus (increases with increased tissue density)
- cough does not alter the sound
- may have bronchial or tubular breath sounds, often with late inspiratory crackles, that do not clear with cough