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Respiratory Exam


July 1st, 2020


Carefully inspect the patient's fingers, looking for discolouration of the nail beds and distal digits.

Tar Staining

  • Look For

  • Yellow staining to the distal phalanges, especially on the 2nd and 3rd digits.
  • Significance

  • An indicator of significant smoking history.
  • Respiratory Complications of Tobacco Smoking

  • Chronic obstructive pulmonary disease
  • Lung cancer

Nail Bed Cyanosis

  • Look For

  • Blue discolouration of the nail beds.
  • Significance

  • Nail bed cyanosis is a type of peripheral cyanosis, characterised by elevated levels of deoxygenated haemoglobin (hypoxaemia) in the peripheries. Always look for central cyanosis (under the tongue) when this is present.
  • Causes of Nail Bed Cyanosis

  • Central Cyanosis

  • High altitude
  • Obstructive lung disease, pulmonary oedema, pneumonia, pulmonary embolism
  • Congenital heart disease
  • Methaemoglobinaemia / sulfhaemoglobinaemia / carboxyhaemoglobinaemia
  • Peripheral Cyanosis

  • As for central cyanosis
  • Reduced cardiac output
  • Vasoconstriction
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