Respiratory Emergencies Flashcards
What is pleural effusion?
Accumulation of fluid in pleural cavity
Note: Not a diagnosis
What are the causes of pleural effusion?
1) Transudative
- Cardiac failure
- Hypoalbuminemia (eg in nephrotic or liver conditions)
2) Exudative
- Bacterial pneumonia, TB, uremia
3) Hemothorax
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4) Traumatic
5) Spontaneous
- Cancer related
- Blood dyscrasias
- Pulmonary embolism with infarction
- Spontaneous pneumothorax
What is the pathophysiology of pleural effusion?
1) Small effusions
- >300ml to be seen on X-rays
- No symptoms
2) Large effusions
- Limited lung expansion -> Reduction in vital capacity -> Hypoxia and hypercapnia
What are the clinical features of pleural effusion?
- Acute pleural pain
- Dyspnea
1) Small effusions
- No findings or
- Shifting dullness on percussion
2) Large effusions
- Dullness on percussion
- Shift of mediastinum
- Decreased chest movements
Investigations for pleural effusion?
1) XRay
- White on affected areas
What is the treatment for pleural effusion?
1) Thoracostomy drainage
- For hemothorax
2) Surgical exploration
- In causes of traumatic hemothorax
- If blood >1000mL is evacuated during thoracostomy
- If continuous bleeding from chest 150-200ml/hr for the next 24 hours
- If persistent blood transfusion is needed
What is a pneumothorax?
Collection of air in the pleural cavity
What are the causes of pneumomthorax?
1) Spontaneous
- Rupture of bullae on lung surface
- Bronchial asthma
- COPD
- TB
2) Chest trauma
- Negative pleural pressure allows air to enter
What are the clinical features of a pneumothorax?
1) Small pneumothorax
- Asymptomatic
2) Large pneumothorax
- Acute pleural pain on inspiration
- Dyspnea
- Shift of mediastinal structures
- Hyper-resonance on percussion
- Absent breath sounds
Investigations for pneumothorax?
1) XRay
- Darker on affected areas
- Marked difference in radiolucency
- Absence of vascular markings
What is tension pneumothorax?
Accumulation of air under pressure in the pleural space
Life-threatening emergency
What is the pathophysiology of tension pneumothorax?
1) Increasing pressures -> Displacement of structures and compressions of heart and vessels -> Reduces venous return/preload to R heart -> Decreases cardiac output -> Hypotension
What are the complications of tension pneumothorax?
1) Decreased VR and CO
- Hypotension and tachycardia
2) Hypoxemia (low blood O2)
- Due to alveolar collapse
3) Re-expansion pulmonary edema
- Rapid process (instead of slow) means damaged capillaries allowing more fluid leakage from increased capillary permeability and inflammatory response
4) Bronchopleural fistula (BPF)
- Sinus tract between bronchus and pleural space
- Continuous flow of air into cavity worsens pain
What are the investigations for tension pneumothorax?
1) Chest radiography
- Low quality film may miss out small pneumothorax
- Supine position avoided
2) CT
- To confirm size and presence of pneumothorax
What is the treatment for tension pneumothorax?
1) Oxygen
- Supplemental O2 speeds absorption of air from pleural space
2) Observation of stable px
- Primary: Observe for 4 hrs, home if no enlargement
- Secondary of iatrogenic: Hospitalise and observe
- May need to drain if any vital signs deterioration
3) Simple aspiration
- Use a 3-way stopcock
- Slowly evacuate until no more air at all
- If 4L of air is removed without resistance, insert chest tube
4) Chest tubes
- Small bore: Small incision, 2nd ICS if midclavicular line or 5-7th ICS if laterally
- Large bore: Blunt dissection in 3 -bottle system
5) Pleurodesis
- Stick your lung to your chest wall and prevent fluid or air from accumulating around it
