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Shock Overview

The word shock is used differently by the medical community and the general public. The connotation by the public is an intense emotional reaction to a stressful situation or bad news. The medical definition of shock is much different.

Medically, shock is defined as a condition where the tissues in the body don't receive enough oxygen and nutrients to allow the cells to function. This ultimately leads to cellular death, progressing to organ failure, and finally, if untreated, whole body failure and death.

How the body works

Cells need two things to function: oxygen and glucose. This allows the cells to generate energy and do their specific jobs.

Oxygen in the air enters the body through the lungs; where oxygen molecules cross into the smallest blood vessels, the capillaries, and are picked up by red blood cells and attached to hemoglobin molecules. The red blood cells are pushed through the body by the actions of the pumping heart and deliver the oxygen to cells in all the tissues of the body. The hemoglobin then picks up carbon dioxide, the waste product of metabolism, where it is then taken back to the lungs and breathed out into the air, whereby the whole cycle begins again.

Glucose is generated in the body from the foods we eat. Glucose travels in the blood stream and uses an insulin molecule to "open the door," where it then enters the cell to provide energy for cellular metabolism.

Medically Reviewed by a Doctor on 12/8/2014
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Patient Comments & Reviews

The eMedicineHealth doctors ask about Shock:

Shock - Treatment

What was the treatment for your shock?

A Typical Night in the ER

Medical Author: Benjamin C. Wedro, MD, FAAEM
Medical Editor: Melissa Conrad Stöppler, MD

The ambulance call comes in.

"We're running lights and siren with a 67 year old male. He's confused, lethargic, blood pressure 80 over 40, thready pulse (a pulse that is very fine and barely perceptible) and sweaty. We'll be at your door in a couple of minutes."

The nurses start setting up the equipment to care for the patient. We've been through this drill before when someone arrives at the ER with low blood pressure. I hope it's an easy diagnosis and something that we can treat quickly. IV's are set up, monitor pads ready. The respiratory tech arrives with her machines just in case they are needed.

The EMTS unload a man in obvious distress, sweaty, struggling to breathe, and limp.

"He's had a fever for a couple of days with a cough. Past history of COPD, heart problems, and smokes."

The diagnosis could be easy, but there are a variety of factors that could be causing this man's condition. He is in shock; his blood pressure is so low there is not enough pressure to provide blood flow and oxygen to his brain. That's why he is lethargic. No doubt the rest of his organs are at risk too. But why?

Read What Your Physician is Reading on Medscape

Shock, Distributive »

Shock is defined as a clinical syndrome due to inadequate tissue perfusion that results in end-organ dysfunction.

Read More on Medscape Reference »

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