Hypovolemic shock is a condition, usually due to a severe injury, in which the body has lost so much blood volume that not enough blood can circulate throughout the body to deliver sufficient oxygen to the vital organs.
Blood, which contains fluid, cells, and other particles, carries oxygen through the body. Oxygen is required to keep body tissues alive. When there is a severe decrease in blood or total body fluid, hypovolemic shock occurs. If this situation is not corrected right away, the person will die.
Hypovolemic shock can cause the following: cold, pale skinconfusionfaintinglow blood pressurerapid heartbeatreduced urine output
Hypovolemic shock is usually caused by massive blood loss or severe dehydration. Blood loss may be the result of gastrointestinal bleeding, internal bleeding due to an injury, a hemorrhage, or severe burns. Dehydration may follow severe diarrhea or vomiting. It can also be caused by excessive sweating or an inadequate intake of oral fluids.
In many cases, hypovolemic shock cannot be prevented. It often occurs after a traumatic injury or severe illness. Dehydration can sometimes be prevented by drinking enough fluids. A drink that balances essential salts and sugars, such as a commercial hydration solution, helps if the vomiting or diarrhea is severe.
Shock is usually diagnosed based on a person's symptoms and a physical exam. If the exact cause of shock is not clear, blood tests, X-rays, and other tests may be done.
Without rapid, effective treatment, hypovolemic shock can lead to irreversible brain and kidney damage. It can also cause cardiac arrest, and ultimately death.
Hypovolemic shock is not contagious, and poses no risk to others.
Emergency treatment for hypovolemic shock includes prompt replacement of fluid and/or blood. Usually, this is done through a needle in a vein known as an IV. Any bleeding sites must be found so that blood loss can be controlled. People in shock are very ill and may need to be put on a ventilator, an artificial breathing machine.
Medicines may be needed to support blood pressure or treat other complications. Surgery may be needed to treat any injuries that are present. Other procedures, such as endoscopy, may be performed to treat specific sites of bleeding so that bleeding will stop.
Blood transfusions can cause allergic reactions and infections. Medicines may include allergic reactions, stomach upset, and other problems. For example, some of the drugs used to support blood pressure can cause irregular heartbeats. Surgery can be complicated by bleeding, infection, or a reaction to the anesthetic.
When shock is treated and people recover, they often do well. Sometimes, permanent damage to organs or tissues requires ongoing treatment.
Depending on the person's health status, monitoring may include physical exams, blood tests, and X-rays. Any new or worsening symptoms should be reported to the healthcare professional.
Harrison's Principles of Internal Medicine, 1998, Fauci et al.