DEAR DOCTOR K:
What does it mean when someone “goes into shock”?
Shock occurs when there is not enough blood flowing through the body to supply the oxygen and nutrients your cells need to survive. People who go into shock can develop organ damage — or even die — if the condition is not treated promptly.
Shock results from extremely low blood pressure, which can result from many different causes.
Low blood pressure may be brought on by a heart problem. A serious heart rhythm abnormality, for example, keeps the heart from forcefully pumping enough oxygen-rich blood throughout the body. So can a heart attack, which weakens the heart muscle.
Low blood pressure also can be caused by severe dehydration, which may result from prolonged vomiting or diarrhea, or by not drinking enough fluids. This lessens the amount of fluid in the blood, which affects blood pressure.
Another cause of low blood pressure is heavy bleeding. Blood loss that is significant enough to cause shock can follow a severe injury, or it may be the result of bleeding from the stomach or intestines. However it happens, just as with severe dehydration, the amount of fluid in the blood vessels drops — and with it, blood pressure.
Shock can quickly develop from chemicals produced by severe infections or a severe allergic reaction called anaphylaxis. The chemicals cause blood vessel walls to become leaky; fluid leaves the blood to go elsewhere in the body. With less fluid, blood pressure drops.
A person is considered to be in shock when he or she has low blood pressure and certain symptoms. These symptoms indicate that there is not enough blood flowing through the body to supply the brain and other organs. Symptoms of shock can include:
- Mental confusion;
- Anxiety or agitation/restlessness;
- Bluish lips and fingernails;
- Chest pain;
- Dizziness, lightheadedness or faintness;
- Pale, cool, clammy skin;
- Low or no urine output;
- Profuse sweating, moist skin;
- Rapid but weak pulse;
- Shallow breathing;
Shock requires emergency medical treatment. The first priority is to get blood pressure back up to normal. This may be done by giving blood and fluids through a vein. Blood-pressure-raising medicines may be administered. They work by narrowing the small arteries or by strengthening the pumping action of the heart.
Anti-shock trousers can help. They squeeze blood from the legs into the heart. Doctors will also give extra oxygen through a mask.
Once blood pressure is back to normal, doctors will shift their focus to treat whatever led to shock in the first place.