What defines distributive shock?

Distributive shock is characterized primarily by the loss of vascular tone, which means that the blood vessels do not maintain their normal diameter, often resulting in widespread vasodilation. This vasodilation leads to a significant decrease in systemic vascular resistance, causing inadequate blood flow to vital organs even though the heart may be pumping normally. In conditions such as sepsis or anaphylaxis, the body’s response to infection or allergen triggers systemic inflammation that results in this loss of vascular tone, thereby contributing to inadequate perfusion despite an adequate or even increased cardiac output.

Recognizing this fundamental mechanism is critical for effective treatment, which might involve fluid resuscitation or vasopressor medications to restore vascular tone and improve circulation. Other choices involve different mechanisms of shock; for instance, the inability of the heart to pump effectively refers more to cardiogenic shock, while physical blockage of blood flow pertains to obstructive shock. Severe fluid loss leading to low blood volume defines hypovolemic shock. Understanding these distinctions helps in diagnosing and treating the specific type of shock accurately.