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Medical Author:

Benjamin Wedro, MD, FACEP, FAAEM

Benjamin Wedro, MD, FACEP, FAAEM

Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Shock is defined as abnormal metabolism at the cellular level. Since it is not easy to directly measure cellular problems, the symptoms of shock are indirect measurements of cellular function. Shock is the end stage of all diseases, and symptoms will often be dependant on the underlying cause.

Vital signs

As the patient goes through the various stages of shock, vital signs change. In the early stages, the body tries to compensate by moving fluids around from within cells to the blood stream with an attempt to maintain blood pressure in a normal range. However, there may be a slight rise in the heart rate (tachycardia = tachy or fast + cardia or heart). For example, donating blood. A unit of blood (or about 10% of the bloods volume) is removed, yet the body compensates well, except for a little lightheadedness, which is often resolved by drinking fluids. Another example is exercising and forgetting to drink enough fluids and feeling a little tired at the end of the day.

As the body loses the ability to compensate, the breathing rate gets faster and the tachycardia increases as the body tries to pack as much oxygen onto the remaining red blood cells as possible and deliver them to the cells. Unfortunately, blood pressure starts to drop (hypotension=hypo or low + tension= pressure) as compensation mechanisms fail.

Body function

Cells don't receive enough oxygen and the organs that they comprise begin to fail. All organs may be affected.

• As the brain is affected, the patient may become confused or lose consciousness (coma).
• There may be chest pain as the heart itself doesn't get an adequate oxygen supply.
• Diarrhea may occur as the large intestine becomes irritated due to hypotension.
• Kidneys may fail and the body may stop producing urine.
• The skin becomes clammy and pale.

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