Shock
Shock is an abnormality of the circulation that results in inadequate organ perfusion and tissue oxygenation.
History
Trauma
Trauma is a pertinent feature in the history, as haemorrhage invariably accompanies penetrating trauma. The site and approximate amount of blood loss should be assessed. Blunt trauma to the chest is associated with tension pneumothorax, myocardial contusion and cardiac tamponade. Trauma to the pelvis and long bones can result in closed fractures, causing significant haemorrhage that may not always be apparent to the observer. Thermal injury can occur with patients involved in fires, water-heater explosions and gas explosions. Acute onset of paralysis following trauma may be due to spinal or peripheral nerve injury. Disruption to the descending sympathetic pathways with spinal injuries, results in loss of vasomotor tone and consequently hypotension.
Dyspnoea
Although tachypnoea is a physiological accompaniment to blood loss, when dyspnoea is the predominant symptom you should consider pulmonary oedema from the causes of cardiogenic shock. In addition, dyspnoea is also a prominent feature of all the causes of obstructive shock.
