Weak or Absent Pulse

What is shock?

Fact Checked

Shock is a dangerous condition where the delivery of oxygen to the bodily organs is low that can result to organ damage and even death. In most cases, the blood pressure is usually low.

An individual can go into a state of shock if the blood pressure is too low in which the cells do not receive enough blood and oxygen. As an outcome, the cells in several organs including the liver, kidney, brain and the heart ceases to function normally. If the flow of blood to these cells is not restored rapidly, they are irreversibly damaged and eventually die. If enough cells are damaged or destroyed, the organ might fail.

Even though low blood pressure is essentially the cause of shock, it might not be low in the initial phases of shock. In addition, the blood pressure can be low among those who do not have shock.

What are the causes of shock?

There are several cause of shock – low blood volume (hypovolemic), significant widening of the blood vessels (distributive) and inadequate pumping action of the heart (cardiogenic).

The condition can start with sleepiness, sluggishness and confusion.

Hypovolemic shock

Low blood volume causes poor supply of blood to enter the heart during every heartbeat, thus limited amount is being pumped out to the body and its cells. The blood volume might be low due to significant bleeding, poor intake of water or excess loss of body fluids.

Cardiogenic shock

Poor pumping action of the heart can lead to insufficient amounts of blood being pumped out during every heartbeat. The usual causes of inadequate pumping action include:

  • Heart attack complications
  • Inability of the heart to fill
  • Blood clot in the lungs
  • Erratic heart rhythm
  • Malfunction of a heart valve
  • Other conditions that affect the heart structure

Distributive shock

Significant dilation of the blood vessels increases the capacity of the blood vessels and lowers the blood pressure. This results to diminished flow of blood and oxygen being delivered to the organs.

The possible causes in which the blood vessels can end up excessively dilated include the following:

  • Severe allergic reaction or anaphylaxis
  • Certain endocrine conditions
  • Severe bacterial infection
  • Injuries to the spinal cord
  • Overdose on drugs or poisons that dilate the blood vessels

What are the indications?

The indications of shock are similar if the cause is low blood volume or poor pumping action of the heart.

  • The condition can start with sleepiness, sluggishness and confusion.
  • Skin becomes cold and sweaty and often pale and bluish. If the skin is pressed, the color returns slower than normal.
  • Blood vessels are more visible as a bluish network of lines beneath the skin.
  • Pulse is rapid and weak unless a slow heartbeat is the cause for the shock.
  • In most cases, the individual could not sit up without feeling lightheaded or passing out.
  • Rapid breathing but both breathing and the pulse rate are slow if death is imminent.
  • There is a drop in the blood pressure that it could not be measured by a blood pressure cuff.
  • Skin becomes warm and flushed and the pulse rate is strong at first if shock is due to excess dilation of blood vessels. However, it can also trigger cold, clammy skin and even lethargy.

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