Pneumonia Flashcards
(138 cards)
Describe the general pathophysiology of pneumonia?
Increased # of microbial pathogens @ alveolar level
Host’s inability to fight off said pathogens
How do pathogens gain access to the pulmonary cavity to cause pneumonia?
Aspiration from oropharynx = MOST COMMON
Inhaled as contaminated droplets
Hematogenous spread = rare
Extension from infected pleural or mediastinal space
What are the defense mechanisms of the respiratory system?
Hairs/turbinates of nares
Branch architecture of tracheobronchal tree –> traps particles in lining
Mucociliary clearance
Local antibacterial factors
Gag reflex
Cough mechanism
Normal flora of the oropharynx
Body’s Immune Response
When will pneumonia occur?
When 1 or more of the bodies defense mechanisms fail
Large Infectious inoculum/virulent pathogen overwhelms immune response
What are the immune responses that triggers the clinical syndrome of pneumonia and what are their symptoms?
Alveolar capillary leak = infiltrate/rales
Alveolar filling = hypoexmia
Leakage of erythrocytes = hemoptysis
What is CAP?
Community Aquired Pneumonia
What is the epidemiology of CAP?
8th most common cause of death in the US –> 25% = hospitalized
4 - 5 million cases/year –> 12/1000
Most common cause of death from infectious disease
Which populations have the highest incidence of CAP?
Extremes of ages: very young and very old
12-18/1000 60 yo
What are the mortality rates of CAP?
Out patient = < 1%
In patient = 10 - 12%
1 year mortality of patents > 65 = 40%
What is the presentation of CAP dependent on?
Progression
Severity
What are the classic signs/symptoms of CAP?
Acute or subacute cough w/ or w/o sputum
Dyspnea
Fever
Chills
Sweats
Chest pain (esp. plueritic) w/ deep breath
Hemoptysis
GI complains = 20% have n/v and/or diarrhea
Fatigue
Head Ache
Myalgias (body Aches)
What is the etiology of CAP?
Strep. pneumonia = MOST common
H. Influenza
S. aureus
In pts w/ a Hx of aspiration, abscess formation, empyemas or parapneumonic effusions, what is the most common cause of CAP?
Anaerobes
In pts w/ a Hx of alcohol abuse, what is the most common cause of CAP?
Klebsiella pneumonia, Strep pneumonia
What are the signs/symptoms of CAP caused by Klebsiella pneumonia?
Necrosis
Hemorrhage
Sputum looks like currant jelly
What is the most common cause of CAP in a pt w/ a Hx of aspiration?
Pseudomonas aeroginose
What are the common risk factors/comorbidities of pneumonia (14)?
Alcoholism
Asthma/COPD
Immunosupression –> chronic steroid use
Institutionalism
> 70
Smoking = STRONGEST RISK FACTOR IN NON ELDERLY/NON IMMUNOCOMPROMISED
increase chance 2-4x
Dementia
Seizure disorder
Cerebrovascular dz
HIV
Structural lung DZ
Introvenous Drug Abuser
Gastric Acid Suppression Therapy
Short duration H+ inhibitors
What would you expect to see on physical exam of a pt w/ pneumonia?
Fever
Tachypnea
Tachycardia
Hypoxia
Increased tactile fremitus (increased chest wall vibration near infection)
Egophony over infected area (E sounds like A)
Altered breath sounds
Crackles
Ronchi
Bronchial breath sounds
Dullness to percussion over infection
When treating an outpatient CAP, should you culture for a specific pathogen?
Not at first
What test do you perform on EVERYONE w/ pneumonia?
Chest X-ray = Classic Exam
What would you expect to see on a chest x-ray of a pt w/ pneumonia?
Patchy airspace infiltrates
Lobar consolidation
Diffuse alveolar/interstitial infiltrates
may or may not see pleural effusion
When would you do a CT scan on a pt suspected of having pneumonia?
Severe cases
Unresolving cases
Complicated Cases
When do you do a follow Chest X-Ray for a pt w/ pneumonia?
At least 6 weeks (otherwise won’t see a difference in X-ray)
What are the Ddx for CAP?
Acute bronchitis
COPD exacerbation
CHF
Lung Cancer
Pulmonary Embolism
Atelectasis
Pulmonary Vasculitis