A seriously ill patient will often develop problems with their heart and circulation. These problems may be due to disease of the heart itself or be secondary to other disease. Problems seen may include: changes in volume and distribution of body fluid, changes in the condition of blood vessels and changes in the ability of the heart to pump blood around the body.

Treatments for these problems may include the administration of fluid and/or the use of medicines that allow control of the heart rate, heart pumping function, volume of body fluid and blood pressure.