Pulmonary edema (summary)

This is a basic article for medical students and other non-radiologists

Pulmonary edema refers to the abnormal accumulation of fluid in the extravascular compartments of the lung. This initially results in interstitial edema and perihilar airspace opacification.

Reference article

This is a summary article; read more in our article on pulmonary edema.

Summary

• epidemiology
  • a wide group of affected individuals
• presentation
  • chest pain
  • shortness of breath
  • diaphoresis
  • desaturation
• pathophysiology
  • abnormal accumulation of fluid in the lungs, leading to impaired gas exchange and possibly respiratory failure
  • causes
    • cardiogenic
      • congestive cardiac failure (CCF)
      • acute myocardial infarction (AMI)
      • valve disease e.g. mitral regurgitation
    • non-cardiogenic
      • numerous causes, see here
• investigation
  • chest X-ray
    • first-line investigation
    • search for potential causes
  • blood tests
    • electrolytes to search for causes
    • renal function
• treatment
  • diuretics
  • oxygen
  • nitrates and morphine (for acute pulmonary edema)
  • respiratory support

Radiographic features

Chest X-ray

• cephalisation of upper lobe vessels
• interstitial opacities
  • peribronchovascular cuffing
  • septal lines (a.k.a. Kerley B lines)
• airspace opacification
  • filling of the alveoli with fluid
  • when severe and acute, has a perihilar or 'batwing' distribution
  • air bronchograms: air-filled bronchi running through fluid-filled alveoli
• pleural effusion

CT chest

• same as CXR
• may see the cause