Haemodynamics and cardiovascular shock

Haemodynamics is the measurement of the circulation within the body. Shock exists when the perfusion of vital organs is inadequate. The use of haemodynamic monitoring aims to identify hypoperfusion early, and allow for its correction in a timely manner, before irreversible organ dysfunction occurs. This article outlines the basic physiology of the circulation and the mechanisms of different forms of shock. Current invasive and non-invasive methods of haemodynamic monitoring are described, such as may be encountered in theatre or in the Critical Unit.