First Aid Refreshers, part 3: Shock

When someone has sustained an injury, we are pretty well conditioned to check for breathing, heartbeat, and profuse bleeding.  In the absence of problems with any of those, we may be tempted to dismiss the injury as “no big deal” when other things may in fact being going on within the body that are harder to observe at a glance.  One of these is shock.

The Definition of Shock

Television dramas and movies like to portray “shock” as a state of disbelief over someone’s fate.  You know, that mumbling denial that so-and-so is gone.  Medically speaking, it has a different definition.  The well-respected NOLS Handbook for Wilderness Medicine quotes a cardiologist as defining shock this way.

“Shock is the inadequate perfusion of tissue with oxygenated blood.  It is a failure of any or all three basic components of the circulatory system- heart, blood vessels, and blood to deliver oxygenated blood to tissues.  Shock is a state in which inadequate oxygen and nutrient delivery and waste product removal leads first to reversible then irreversible tissue damage.   Bodily processes slow, and tissues begin to die.”

Shock is often related to inadequate blood pressure.  This can be caused by a decrease in blood volume (from profuse bleeding, for example), hypoglycemia, electrocution, hypo/hyperthermia, extreme pain, allergic reaction (food/bites/stings), drug overdose, or loss of fluids through infection, burns, excessive diarrhea, or dehydration.  A loss of half a liter of blood is enough to affect blood pressure.  One and a half liters (25% of an adult’s blood volume) can cause moderate shock.  More than that is quite serious.

Following a heart attack, the cardiac muscle is sometimes so damaged that it cannot maintain an adequate movement of blood through the body.  This can lead to shock also.

Blood vessel dilation can cause blood pressure to drop occasionally.  This sometimes happens in spinal cord injuries when the nerves are damaged.

Initial Signs of Shock:

1. Rapid, but weak or irregular pulse
2. Pale, cool, clammy skin
3. Nausea
4. Restlessness (“fight or flight” response)
5. Profound weakness

 Advanced Signs of Shock:

1. Persistence of the above listed signs rather than gradually going away
2. Increasing pulse rate
3. Shallow, rapid breathing
4. Irritability
5. Extreme thirst

How to Treat Shock

Shock often accompanies major injuires or serious illness.  You must tend to those wounds or symptoms, but always assume that shock may occur and treat before it becomes evident.

Start with basic life support- airway, breathing, and circulation (the ABCs).  Control bleeding and stabilize fractures or other injuries.    From there, do the following:

With a conscious victim:

1. Position the injured person on his back if possible.  If the victim is short of breath, they may be more comfortable propped up.
2. Protect the patient from extremes of heat or cold.  You want them to maintain a normal internal body temperature.  This may include insulating him from cold wet ground, providing shelter from weather, or replacing wet clothes with dry.  Take special care to keep head, neck, hands, and feet covered.  If insufficient bundling material is available, lie alongside the patient to share your heat.
3. Consider elevating the person’s legs.  Unless an injury (like serious head trauma) is present that prevents it, try to raise the patients’s legs at least 8 inches to improve blood return to the heart and brain.
4. Give fluids under some circumstances.  While it may seem automatic, this one must be considered carefully.  If the injured person is likely to need surgery in the next several hours, withhold fluids to prevent the risk of aspiration.  Also, hold off with patients whose mental state is not clear or if they have an abdominal injury.  When giving liquids, plain water is good.  Beware of drinks including much sugar or salt as they may interfere with liquid absorption or be nauseating.  Do NOT offer anything with a sedative effect (like codeine).
5. Evacuate to a hospital if possible.  Any person exhibiting shock whose condition does not stabilize within a couple of hours needs advanced medical support if it is available.

With an unconscious victim:

1. Lay him on his side with head low, tilted back, and to one side.  Make sure the airway is clear in case of vomiting.
2. If he vomits, be sure his mouth is cleared immediately so none is aspirated into the lungs.
3. Do not give liquids or anything else by mouth.

We have compiled a nice home library of reference materials.  I used the following books to refresh my own memory and compile this information for you:

• Where There Is No Doctor by David Werner
• Wilderness Medicine:  Beyond First Aid by Wm. Forgey, M.D.
• Medicine for the Outdoors:  A Guide to Emergency Medical Procedures and First Aid by Paul S. Auerbach, M.D.
• Wilderness Medicine- National Outdoor Leadership School by Tod Schimelpfenig

Know of any other medical books that are must haves for the prepper?

Related Posts

• First Aid Refreshers, part 1 (Working With Your Body)
• First Aid Refreshers, part 2 (Wound Care)
• Water Rescues:  Reach, Throw, Go
• The Many Varied Uses of Diatomaceous Earth