Pneumonia Flashcards
What is pneumonia? What are the 4 types?
Acute lower respiratory tract infection causing inflammation of lung alveoli .
- CAP - primary or secondary to underlying disease
- HAP - hospital acquired pneumonia - >48hr after admission
- Aspiration - happens to people with stroke, myasthenia, bulbar palsies, reduced consciousness, oesophageal disease, or poor dental hygiene.
- Immunocompromised patient
Histologically there is bronchopneumonia and lobar pneumonia.
How do you confirm and diagose a pneumonia?
X Ray - must have consolidation
List the typical and atypical organisms causing community acquired pneumonia.
Typical (85%): streptococcus pneumoniae, haemophilus influenzae
Atypical(15%): legionella, mycoplasma, coxiella, chlamydia.
Viruses account for up to 15%. Flu may be complicated by community-acquired MRSA pneumonia.
What are the causes of hospital acquired pneumonia?
Most commonly gram -ve enterobacteria or staph. aureus. Also pseudomonas, klebsiella, bacteroides, and clostridia.
Which microbes most commonly cause pneumonia in immunocompromised patients?
- Strep. pneumoniae
- H. influenzae
- Staph. aureus
- M. catarrhalis
- M. pneumoniae
- Gram -ve bacilli and pneumocystis jirovecii (formerly named P carinii)
- Other fungi, viruses (CMV, HSV) and mycobacteria
What are the symptoms of pneumonia?
- Fever
- Rigors (sudden cold feeling)
- Malaise
- Anorexia
- Dyspnoea
- Cough
- Purulent sputum
- Heamoptysis
- Pleuritic pain
What are the signs associated with pneumonia?
- Pyrexia
- Cyanosis
- Confusion (can be the only sign in the elderly, may be hypothermic)
- Tachyponea
- Tachycardia
- Hypotension
- Signs of consolidation (reduced expansion, dull percussion, increased tactile vocal fremitus, bronchial breathing)
- Pleural rub
What tests would you do if you suspect pneumonia?
- Assess oxygenation: oxygen saturation, ABGs, and BP.
- Blood tests: FBC, U&E, LFT, CRP (GPs should consider a point of care CRP to guide antibiotic prescription where LRTI is suspected, NICE 2014)
- CXR: lobar or muultilobar infiltrates, cavitation, or pleural effusion
- Sputum: for microscopy and culture
- Urine: check for legionella and pneumococcal urinary antigens
- Pleural fluid: aspirate for culture
- Bronchoscopy and bronchoalveolar lavage: if the patient is immunocompromised or on ITU
How do you assess the severity of pneumonia?
- BUT this system may underscore the young so use clinical judgement. Other factors increasing risk of death: comorbidity, bilateral/multilobar. PaO2 <8kPa*
- In GP setting urea not used and a score of 2-3 definitely needs consideration of admission.*
How do you manage pneumonia?
- Antibiotics - broad spectrum initially then according to culture results
- Oxygen to keep PaO2>8kPa and/or saturation >94%
- IV fluids (anorexia, dehydration, shock)
- VTE prophylaxis
- Analgesia if pleurisy
- Follow up at 6 weeks for a CXR
What are the complications of pneumonia?
- Pleural effusion
- Empyema
- Lung abscess
- Respiratory failure
- Septicaemia
- Others: Brain abscess, pericarditis, myocarditis, cholestatic jaundice, repeat CRP and CXR in patients not improving to look for progression/complications.
Which antibiotics would you give for mild-mod CAP?
Consult the local guidelines
Amoxicillin 0.5-1g PO TDS 5 days
[penicillin allergic: clarithromycin 500mg PO BD 5 days]
Which antibiotics would you give for severe CAP?
- Co-amoxiclav 1.2g IV TDS AND
- clarithromycin 500mg PO/IV BD
Switch to oral when afebrile for 48hrs and continue for 5 days
[levofloxacin 500mg PO/IV BD 5 days]
Which antibiotics for non-severe vs severe HAP?
Non-severe:
- Doxycycline 200mg PO stat then 100mg BD 5 days
- [co-trimoxazole 1.44g PO/IV BD if allergy]
Severe:
- Co-trimoxazole 1.44g PO/IV BD 5 days OR (co-amox 1.2g IV TDS + gentamicin IV)
Which antibiotics to treat aspiration pneumonia?
Co-trimoxazole 1.44g PO/IV BD
AND metronidazole IV 500mg or 400mg PO TDS
for 7 days
Which at-risk groups should get the pneumococcal vaccine?
- All adults over 65
- Chronic heart/liver/kidney/lung conditions
- Diabetes mellitus or not well controlled diabetes
- Immunosuppressed e.g. low spleen function/AIDs/on chemotherapy or prednisolone >20mg/d
CI - pregnant/lactating/anaphylaxis to previous vaccine
Describe the type of respiratory failure you can get in pneumonia.
Type 1 - PaO2 <8kPa
Treat with high flow oxygen (60%) and transfer to ITU if it does not improve.
If rising PaCO2/worsening acidosis then consider elective ventilation
Aim to keep saturations at 94-98% and PaO2 at >8kPa
What are the causes of lung abscess ?
- Inadequately treated pneumonia
- Aspiration (e.g. alcoholism, oesophageal obstruction, bulbar pasly)
- Bronchial obstruction (tumour, foreign body)
- Pulmonary infarction
- Septic emboli (septicaeamia, right heart endocarditis, IV drug use)
- Subphrenic or hepatic abscess