(Dyspnea actually is a shortness of breath in medical term.)
Dyspnea (Breathlessness) is a non-specific symptom and may be caused by cardiac, respiratory, neuromuscular and metabolic conditions, or by toxins or anxiety.
Dyspnea may be caused by myocardial ischaemia and is known as ‘angina equivalent’. It may occur instead of, or with, chest discomfort, especially in elderly and diabetic patients. It has identical precipitants to angina and may be relieved by GTN.
Dyspnea in heart failure may be associated with fatigue. Pulmonary oedema (accumulation of fluid in the alveoli) occurs with left heart failure because increased left atrial enddiastolic pressure leads to elevated pressure in the pulmonary veins and capillaries.
Causes of Dyspnea:
Causes of dyspnea include:
• Metabolic acidosis
• Left ventricular failure
• Mitral valve disease
• Constrictive pericarditis
• Pericardial effusion
• Laryngeal tumour
• Foreign body
• Lung cancer
• Cystic fibrosis
• Pulmonary fibrosis
• Diffuse infections, e.g.Pneumocystis jirovecipneumonia
• Tumour (metastatic, lymphangitis)
• Pulmonary thromboembolism
• Pulmonary vasculitis
• Primary pulmonary hypertension
• Diffuse pleural fibrosis
• Ankylosing spondylitis
• Myasthenia gravis
• Muscular dystrophies
• Guillain–Barré syndrome
Types of Dyspnea:
• Paroxysmal nocturnal dyspnea is sudden breathlessness waking the patient from sleep. It is caused by accumulation of alveolar fluid.
• Orthopnoea is dyspnea on lying flat and is a sign of advanced heart failure. Lying flat increases venous return and in patients with left ventricular impairment may precipitate pulmonary oedema. The severity can be graded by the number of pillows used at night, e.g. ‘three-pillow orthopnoea’.
• Platypnoea is breathlessness on sitting upright. It is much rarer than orthopnoea and is usually associated with deoxygenation (platypnoea–orthodeoxia syndrome). It requires both anatomical and functional abnormalities.