What Is Shock?
Shock is the medical term for the emergent situation that occurs when tissues in the body are not receiving enough nutrients and oxygen to properly function. If the body is left in shock for too long, cells begin to die and eventually organs will shut down, leading to death. Shock is often the body's reaction to severe injuries or illnesses.
Biology of Shock:
Cells function with two basic components - oxygen and glucose. When air enters the body through the lungs, the oxygen crosses into the blood stream and is taken up by red blood cells. Those blood cells travel through the body and deliver the oxygen to individual cells. The same blood cells then pick up carbon dioxide from other cells and transport it back to the lungs, where it's processed back out of the body through respiration.
Similarly, glucose is created as a product of processing food we eat. The glucose travels through the blood stream via insulin, produced by the pancreas. Insulin travels through the bloodstream, delivering glucose to the cells in a fashion similar to oxygen transport via red blood cells.
When cells are not able to receive either glucose or oxygen, cells produce energy using an anaerobic (without oxygen) process instead, forming lactic acid. The addition of lactic acid causes the body to leak toxic chemicals in to the bloodstream, damaging other cells, and leading to cell death. When enough cells die, organs fail and the body dies.
The shock process can be caused by a breakdown in any of the areas of the delivery system. For example, extreme illness that affects the lungs, such as pneumonia, can decrease the lungs' capacity to take in oxygen. Similarly, carbon monoxide poisoning, high altitude, and other breathing deficiencies caused by injury can have the same affect.
The shock process can also be instigated by a breakdown in the blood processing function. Congestive heart failure is a common cause of lungs filling with fluid, decreasing blood flow and decreasing lung capacity. The heart may not be able to adequately move blood around the body. This includes heart attack, inflammation, and anemia.
Severe dehydration can also cause shock. For example blood, which is 90% water, needs enough fluid to maintain pressure against the walls of veins and arteries. If there is not enough water in the blood, the walls collapse and restrict the ability of blood to flow through blood vessels. Finally, injury can cause enough blood loss that there is not enough blood in the system to adequately move blood through the body.
Types of Shock:
In addition to general shock, there are several specific kinds of shock that can affect the body.
Hypovolemic Shock: This is a condition in which the percentage of red blood cells is too concentrated for the body, leading to inadequate pressure against the vessel walls. Hypovolemic means "low volume." Other situations that cause hypovolemic shock include gastroenteritis (loss of water through diarrhea and vomiting), heat exhaustion, sun stroke, and sweating (through fever).
Hemmorrhagic shock occurs when a person has lost a significant amount of blood, typically from trauma or serious injury. Medical conditions such as ulcer, cancers, diverticulitis, uterine bleeding, and those taking blood thinners can cause excessive bleeding. People can lose approximately 10% of their blood before beginning to feel the effects of shock.
Cardiogenic shock - This is caused by a decreased ability of the heart to pump blood. When a heart attack happens, the muscle is weakened and unable to push blood around the body.
Neurogenic shock - This is the state in which your body is no longer able to keep consistent pressure on your blood vessels, regulating blood flow. If blood flow is not regulated, it flows away from the brain and in to the lowest point on the body.
Hypo/Hyperglycemia - This is a situation in which the blood sugar level in the body is too low or too high. This can be caused by not eating enough, anorexia, diabetes, and dehydration. The body responds drastically by producing excessive glucose (hyper), losing water because the kidneys work over time. It can also cause a person to go in to a coma (hypo).
Symptoms of Shock:
- Abnormal paleness
- Low blood pressure (leading to a feeling of being light-headed or dizzy)
- Shortness of breath
- Loss of consciousness
- Chest pain
- Lack of urine
- Clammy skin
- Nausea or vomiting
- Dilated pupils, lackluster gaze or blank stare
Diagnosis of Shock:
If you suspect shock, call 911 or other emergency medical line immediately.
Blood tests, vitals monitoring, x-rays, and heart or brain tests can be utilized to diagnose shock.
First Aid for Someone in Shock:
Shock is an emergency situation. Call 911 immediately if you suspect shock.
To aid someone with symptoms of shock:
- Aid them in lying down on their back (if conscious) with feet elevated approximately 12" above the head (unless positioning will cause or aggravate injury or pain).
- Roll the individual onto their side if unconscious, nauseous, or vomiting to avoid airway obstruction.
- Check vital signs and perform CPR if appropriate.
- Assist with comfort measures - provide a blanket or loosen restrictive clothing; however, do not provide food or drink. Emotional reassurance is also important to maintain calm.
- Manage external bleeding with application of clean cloth compresses.
- Seek professional medical care as soon as possible.
Shock is treated in a few ways, and greatly depends on the reason for the shock. Sometimes additional food or fluid is enough to revitalize the body. Other times it is more complicated, and in the case of a coma, brain function may not ever be recovered.
Additional Shock Resources:
The American Red Cross provides First Aid and CPR Training Courses.
The American Hearth Association offers classes to the community and provides an app for the iPhone that has guides for first aid and CPR.