ABSTRACT
Shock is the most common cause of death of surgical patients. Death may occur rapidly because of a profound state of shock or may occur later because of the consequences: of organ ischaemia and reperfusion injury. Shock is a systemic state of low tissue perfusion that is inadequate for normal cellular respiration. Hypoxia and acidosis activate complement and prime leukocytes, resulting in the generation of oxygen free radicals and cytokine release. The metabolic acidosis and increased sympathetic response result in an increased respiratory rate and minute ventilation to increase the excretion of carbon dioxide. Hypovolaemia may be due to haemorrhagic or non-haemorrhagic causes. Cardiogenic shock is due to primary failure of the heart to pump blood to the tissues. Distributive shock describes the pattern of cardiovascular responses characterising a variety of conditions, including septic shock, anaphylaxis and spinal cord injury.
