Acute Medicine | Breathlessness 18 knowledge A

Causes of Anaemia Associated with Breathlessness
Session Overview
Description
This session will look at the classification of anaemia based on red cell indices and the associated factors leading to breathlessness in an anaemic patient.

Learning Objectives
By the end of this session you will be able to:

• Describe which associated factors are likely to lead to breathlessness in an anaemic patient and the causes of anaemia based on red cell indices

The World Health Organisation defines anaemia as a haemoglobin (Hb) level below 12g/dL in women or 13g/dL in men; although local ranges may vary. Anaemia causes breathlessness by reduced oxygen delivery to the tissues.

It is important to be aware that not all anaemic patients are breathless. Many patients with breathlessness are, however, anaemic.

The degree to which an individual patient’s breathlessness is due to the anaemia depends on many factors.

Anaemia is not a diagnosis in itself and a cause for anaemia should always be sought. Different classifications of anaemia exist based on pathophysiology and other factors. However, the most useful classification of anaemia is that based on the red cell indices dividing anaemia into microcytic hypochromic, normocytic and macrocytic causes.