Infection, bronchiectasis + CF Flashcards
(33 cards)
Describe the common pathogens causing pneumonia and their associations
CAPs:
- Strep pneumonia
- S aureus
- Haemophilus influenzae
- Viruses: influenzae, coronavirus
- Klebsiella: alcoholics
- Pseudomonas: bronchiectasis, COPD
Atypicals:
- Mycoplasma pneumonia
- Legionella pneumoniae: air-conditioners, water sources
HAPs:
- Gram -ve enterobacter
- S aureus
Immunocompromised:
- PCP
- TB
- Fungi
Describe the presentation of pneumonia
Commonly:
- Productive cough
- Fever
- CP, SOB
- Severe: sepsis
Atypicals: dry cough, confusion, hepatitis, headache, flu-like symptoms etc
Describe the signs of pneumonia on examination
General: tachycardia, tachypnoea, generally unwell, pyrexial, sweaty, rigors
Chest:
-Dullness to percussion
-Crackles on auscultation
Describe the investigations for pneumonia
History + examination
- ECG if CP
- Urine sample (rapid Ag test), sputum sample (MCS)
- Bloods: FBC, CRP, U+Es, consider LFTs/cultures as needed
- CXR
Describe how the severity of pneumonia is assessed
If 2+: severe pneumonia. Admit CURB 65 Confusion Urea >7 RR >30 BP low Age >65
Describe the antibiotic management of pneumonia
CAP:
- Mild (CURB65 0-1): amox 500mg TDS 5 days OR doxy/clari/erythro
- Mod (CURB65 2): amox + clari (500mg BD)
- Sever (CURB65 3+): coamox (500/125 PO or 1.2g IV) + clari
HAP:
-Co-amox 500/125 TDS 5 days
Name some complications of pneumonia
Respiratory failure Sepsis Empyema Bronchiectasis Pleural effusion
Define type I and type II respiratory failure
Type I: PaO2 < 8 kPa
Type II: PaO2 < 8 kPa and PaCO2 >6.5 kPa
Describe the aetiology of respiratory failure
V/Q mismatch:
- Vascular causes: PE, PHTN
- Pneumothorax
- Atelectasis
Alveolar hypoventilation:
- Obstructive causes: asthma, COPD, bronchiectasis
- Restrictive causes: ILDs, CNS sedation, neuromuscular disease (GBS, MG), fluid
Describe the management of respiratory failure
Treat cause
Type I: high flow O2 to keep sats 94-98%, consider ventilation
Type II: Venturi mask 24% O2 to keep sats 88-92%, consider NIV
Describe the ways of administering oxygen therapy and when they are used
Nasal cannulae: 2-6L/min, 24-40% FiO2 (very variable FiO2 achieved). Most pts needing O2 who are not critically unwell
Face mask: alternative to nasal cannulae, not as well tolerated.
Venturi mask: 2-4L/min, very specific FiO2 achieved- 24-60% FiO2 (usually start with blue, 24%). For pts with chronic hypercapnia
Non-rebreathing mask: 15L/min, 60-80% FiO2. For critically ill pts
Define bronchiectasis
Bronchiectasis is permanent dilatation of the bronchi due to destruction of the elastic and muscular components of the bronchial wall
Describe the aetiology of bronchiectasis
- Typically due to severe/recurrent infections
- Congenital disorders: CF, Kartagener’s/PCD
- Immunodeficiency: HIV, SCIDs, etc
- Connective tissue disease
- COPD and asthma
Describe the pathophysiology of bronchiectasis
Inflammation -> destruction of bronchial wall components -> dilatation and predisposition to infection -> recurrent infections etc
Describe the presentation of bronchiectasis
Typically:
- Persistent productive cough
- Recurrent chest infections
- Progressive SOB
- Fatigue
- Haemoptysis
Describe the signs of bronchiectasis on examination
General: may have weight loss
Hands: clubbing
Chest: widespread coarse crackles, rhonchi, wheeze
Describe the investigations for bronchiectasis
- History and exam suggestive
- Sputum sample (MCS)
- Bloods (exacerbation): FBC, CRP, U+Es
- CXR (if suspecting acute infection- not for Dx)
- HRCT (diagnostic!!!): dilatation, signet ring sign, tram lines
- Spirometry
To investigate cause:
- Chloride sweat test
- Serum a1 antitrypsin
- Ig levels
- HIV serology
- RF and antibody screen
Describe the management of bronchiectasis
Conservative:
- Chest physio
- Vaccinations
- Smoking cessation
Medical:
- Maintenance: mucolytics, nebulised hyperosmolar solutions (hypertonic saline), prophylactic antibiotics (may have emergency pack at home)
- Acute exacerbations: antibiotics
Surgical:
-For complications eg. pneumothoraces
Describe the complications of bronchiectasis
Pneumonia Pleural effusions Pneumothorax Pulmonary HTN and RHF Massive haemoptysis
Describe the epidemiology of CF
One of the commonest genetic conditions
Common among white people
Describe the pathophysiology of CF
Defects in the CFTR gene encoding a transmembrane chloride channel -> impaired absorption of electrolytes + water -> thick mucous in exocrine glands
Describe the presentation of CF
May be detected:
1) Antenatally
2) At birth on Guthrie spot test
3) With cough, failure to thrive in childhood
4) Later in life with recurrent infections, bronchiectasis, etc
Describe the signs of CF on examination
General: thin/malnourished, pale
Hands: clubbing
Chest: hyperinflation, signs of infection (coarse crackles), bronchiectasis (rhonchi, crackles)
Describe the investigations for CF
Diagnosis:
- Guthrie spot: immune reactive trypsinogen
- Chloride sweat test to confirm/later life Dx
- Genetic mutation testing
- Faecal elastase for pancreatic insufficiency
Investigations if general presentation (eg. infection):
- Sputum sample
- Bloods: FBC, CRP, U+Es
- CXR
