diaphragmatic paralysis

Etiology

• chronic diaphragmatic paralysis (> 6 months) is generally idiopathic
• hilar mass may cause acute unilateral diaphragmatic paralysis

Clinical manifestations

• unilateral: frequently associated with hemiplegia
• bilateral: orthopnea Pulmonary function testing:
• unilateral
  • decreased total lung capacity by 35%
  • decreased vital capacity by 20%
  • decreased maximal voluntary ventilation by 20%
• bilateral
  • decreased vital capacity
    • 50% in the upright position
    • 60-75% in the upright position
  • decreased maximal voluntary ventilation by 20%

Laboratory

• diaphragmatic electromyography

Radiology

• elevated diaphragm or hemidiaphragm on chest X-ray
• diaphragmatic fluoroscopy:
  • demonstration of paradoxical motion
  • 6% of normal subjects have positive findings

Management

• exclude hilar mass with acute unilateral diaphragmatic paralysis

More general terms

• diaphragm disorder
• paralysis

More specific terms

• hemidiaphragm paralysis; elevation of one hemidiaphragm

Additional terms

• diaphragm muscle