Distributive shock is a medical crisis where a patient has a normal blood volume, but the blood does not circulate effectively, leading to oxygen deprivation in the patient's tissues. If the patient does not receive treatment, severe injuries to organs and tissues can develop and the condition may be fatal. This is one form of shock, a medical condition where patients do not get enough blood to meet their needs. Other examples include hypovolemic shock, where patients lose large amounts of blood, and cardiogenic shock, where the heart is not beating enough to circulate the blood.
In distributive shock, the blood vessels dilate far too much, causing blood pressure to drop. This makes it difficult to push blood throughout the circulatory system. Patients can also experience blood pooling, where blood sinks to the lowest parts of the body with the help of gravity and then cannot move. Tissues start to experience hypoxia and may turn grayish or blue. Cramps and pain can occur as the patient's body tries to adjust to the inadequate oxygen.
The heart rate is usually normal, but inadequate for the patient's needs. In some cases, the heart will start to pump harder to try to raise blood pressure and push the blood where it needs to go. This can create considerable stress on the patient's body. Treatment options can involve administration of vasoconstrictors to tighten up the blood vessels, as well as treatment of the underlying cause of the shock with the goal of getting the patient stable.
Some types of distributive shock include neurogenic, anaphylactic, and septic shock. In patients with the neurogenic form of this condition, injuries to the brain or spinal cord interfere with the function of the blood vessels, causing them to relax. The open blood vessels lead to a drop in blood pressure, depriving tissues of their needed oxygen and nutrients. In patients with anaphylactic shock, an acute allergic reaction, a cascade of inflammation caused by histamine release triggers vasodilation and leads to distributive shock. Patients with septic shock have a severe infection that results in widening blood vessels, usually because of toxins released by bacteria.
If care providers identify distributive shock in a patient, they need to act quickly to provide treatment. This condition can be fatal, sometimes very rapidly, and can also cause serious damage to the patient's heart and other organs. Getting blood pressure up to improve circulation is the first step, keeping the patient alive long enough for doctors to start addressing the cause.