Fast breathing due to other causes – blood loss
This will be covered in more detail in the chapter about shock.
Our circulation carries essential nutrients such as oxygen and glucose to the cells of the body and takes away waste products like carbon dioxide. If we lose a significant amount of blood either internally or externally, the ability of the circulation to meet the oxygen needs of the body may be challenged. As a result, one of the changes that occurs is the brain makes us breathe more frequently to help take on more oxygen and breathe away more carbon dioxide. Casualties with insufficient blood in the circulation may appear pale and confused as well as be breathing faster than you would expect for the setting. Remember that it usually takes a little time for people to lose enough blood to show signs of shock. Early breathing problems are more likely to indicate pain or injury.
Medical problems and asthma will be covered in a separate chapter.