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Flashcards in 105 - Pleurisy Deck (31):

What are the differences between the pulmonary arteries and systemic arteries?

  • Pulmonary arteries are ~30% thinner walled compared to systemic.
  • The small arterial vessels in the lung contain relatively little smooth muscle compared to systemic


What are the symptoms and signs associated with pleural effusion?

  • Gradual SOB with unilateral pleuritic chest pain
  • Increased RR


  • Reduced expansion and breath sounds
  • Stony dull PN
  • Slight hypoxia and cyanosis may be present
  • Tracheal deviation away from affected side may be present.


What are the 3 things that, according to Light's criteria, indicate an exudative pleural effusion?

  1. Ratio of pleural fluid protein to serum protein is greater than 0.5
  2. The ratio of pleural fluid LDH and serum LDH is greater than 0.6
  3. Pleural fluid LDH is greater than 0.6 or 2/3 times the normal upper limit for serum


What are the 4 types of airflow?

  1. Laminar
  2. Oscillatory
  3. Transitional
  4. Turbulent


Define pneumothorax

Air in the pleural space.


What 2 diagnostic tests are routinely performed to confirm a pleural effusion?

  • Chest X-ray
  • Ultrasound


What are the primary causes of an exudate pleural effusion?

  • Neoplastic
  • Infection
  • Inflammatory
  • Post-operative
  • Trauma
  • Pulmonary embolus


What 2 mechanisms shunt ventilation and perfusion from a hypoxic area of the lung?

  1. A deficiency of O2 and an increase in CO2 lead to vasoconstriction diverting blood away from the area.
  2. Diverted blood means a lower Pco2 leading to bronchial constriction.


These shift both ventilation and perfusion away from the area.


How much volume is required in a pleural effusion for clinical signs to develop?

Around 300ml


What tests are performed on extracted pleural fluid?

  • pH (
  • Cytology
  • Protein
  • LDH
  • Glucose
  • AFB
  • General culture


What are the symptoms of a tension pneumothorax?

  • Sudden onset of unilateral pleuritic chest pain
  • Dry cough
  • Increased RR and HR
  • Dereased BP
  • Dyspnoea
  • Hypoxia and slight cyanosis


  • Reduced expansion
  • Hyper-resonance and diminished breath sounds
  • Tracheal deviation away from affected side


What constitutes the borders of the "safe area" for insertion of a chest drain?

A triangle in the 5th ICS in the mid-axillary line, marked out by:- diaphragm- latissimus dorsi- pectoralis major


What are the 2 main areas of resistance within the respiratory tract?

  1. Oro- and nasopharyngeal cavities - 50%
  2. Bronchioles - remaining 50%


What is Bohr's equation used for?

To calculate the amount of physiological dead space within the lungs


What are the 2 main categories of pleural effusion?

  1. Transudate
  2. Exudate


What is the best way to manage a tension pneumothorax?

  • 100% High flow O2
  • Immediate needle thoracocentesis in 2nd ICS in MCL should produce hissing sound
  • Converts to simple pneumothorax and then normal treatment; chest drain etc


When should a chest drain be removed?

When there is no swinging in the bell of water, indicating that all the fluid has been drained.


What further investigations are performed in the investigation of a transudative pleural effusion?

  • ECHO
  • LFTs
  • U & Es


What pressures maintain the small volume of fluid in the lungs?

Pulmonary circulation is about 10mmHg, whereas the oncotic pressure is about 25mmHg.This means there is an inward force of 15mmHg acting on the fluid in the alveoli.


What further tests are performed forthe investigation of an exudative pleural effusion?

  • CT thorax
  • Thoracoscopy/ VATS


What is the alveolar gas equation useful in determining?

The alveolar partial pressure of oxygen from data that is practically measurable.


What is the management options for a simple pneumothorax?

  • Needle aspiration
  • Chest drain
  • Surgery - Talc/tetracycline, pleurodesis or pleurectomy
  • Endobronchial valves


What are the iatrogenic causes of pneumothoraces?

  • Central line
  • Nerve blocks
  • Liver/lung biopsy
  • Positive ventilation pressure


What primary investigations are performed for a simple pneumothorax?

  • Chest X-ray on maximal inspiration
  • CT scan of thorax


What is the difference between primary and secondary pneumothoraces?

  • Primary pneumothorax; no apparent cause, and not cause by disease; congenital blebs in young, tall men (think Marfans)
  • Secondary pneumothorax; associated with lung disease, usually COPD


Where on the chest is a simple aspiration performed?

In the intercoastal space towards the top of the area of dullness


What are the symptoms of a pneumothorax?

  • Mild dyspnoea
  • Sudden onset of unilateral pleuritic chest pain
  • Increased RR and HR


  • Reduced expansion
  • Hyper-resonant PN
  • Diminished BS
  • Slight hypoxia and cyanosis may be present


What are the main causes of a transudate pleural effusion?

  • Renal failure
  • Heart failure
  • Liver failure


What is the main difference between transudate and exudate pleural effusions?

  • Transudate; protein content of less than 30g/L
  • Exudate; protein content of more than 30g/L


When would an endobronchial valve be inserted?

If there was a Bronchopulmonary fistula and persistent pneumothorax.


What are the dangers of a tension pneumothorax?

  • Compression of good lung leading to hypoxia and cyanosis
  • Compression of the heart and kink/occlusion of VC
  • Can cause cardiac arrest; pulseless electrical activity.