What Causes Shock?
Shock can be the result of numerous different pathophysiological processes that can be broadly accommodated within four somewhat artificial categories: hypovolaemic, distributive, obstructive and cardiogenic. [8] (Table 1)
Irrespective of the cause the inadequate delivery of oxygen to tissues results in a failure of aerobic metabolism leading to end organ dysfunction.
The situation becomes more confusing if examples of dysoxia are considered to be types of shock. Cyanide poisoning is a classic example wherein mitochondria are prevented from using oxygen. Such disease states are outside the remit of this module as the primary problem is not one of circulatory compromise.
| Hypovolaemic (inadequate circulating volume secondary to fluid loss) |
Distributive (inadequate perfusion secondary to |
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Obstructive (inadequate cardiac output as a result of mechanical obstruction) |
Cardiogenic (inadequate cardiac output as a result of cardiac failure)
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Learning bite
Shock describes a pathophysiological state with many different causes, NOT a specific diagnosis.