How to Treat Shock in Remote and Wilderness Environments

A few years ago I was involved in a search and rescue incident where a woman fell about 30 feet while scrambling on boulders.  She was found lying on her back, afraid to move, with a lot of pain in the pelvic region but with intact sensation and movement in her hands and feet.  Her heart rate and breathing were rapid, she was pale and cool to the touch, and very anxious.  Our medical team stabilized her using a full body vacuum splint, then moved her to a small clearing where she was hoisted into a National Guard helicopter and then transferred to an air ambulance.  Her level of responsiveness and blood pressure stayed stable throughout the lengthy extrication, and she survived the incident.  

What was our number one concern?  You might be thinking about spinal injuries, but the biggest life threat for this patient was in fact shock, due to internal bleeding from a possible pelvis fracture.

Shock is one of our favorite topics to teach in wilderness first aid classes, because people who aren't medical professionals often misunderstand the difference between clinical shock and the more common response to traumatic experiences.  Clinical shock is a very serious condition that will lead to death if untreated.  In fact, regardless of the initial cause, everyone ultimately dies of shock. So what is shock and how do we recognize and treat it?

Definition of Shock

In medical terms, clinical shock can be defined as "widespread inadequate perfusion".  Perfusion means that the blood vessels are delivering oxygenated blood to body tissues.  In shock, the patient isn't circulating enough oxygenated blood, particularly to the vital organs.  Our cells need oxygen to function, and when we don't get enough blood flow those cells stop working and start to die.   There are a lot of reasons why someone might not be circulating enough oxygenated blood, so let’s look at causes and types of shock.

Causes and Types of Shock

Shock can be caused by anything that prevents the body from oxygenating and circulating blood.  Low blood volume from bleeding or dehydration, heart problems, airway and breathing issues, and changes in our blood vessels due to allergy, infection, or traumatic injury to the head or spine all can lead to shock.

We can categorize shock into a few different types:

• Cardiogenic shock - due to heart problems such as heart attack
• Hypovolemic shock – due to dehydration or severe internal or external bleeding
• Anaphylactic shock – due to a severe allergic reaction
• Septic shock – resulting from a widespread infection 
• Neurogenic shock – caused by damage to the head or spine
• Obstructive shock – something blocking the heart from pumping, like pericardial tamponade

You may notice that experiencing something emotionally traumatic isn’t on the list.  So before we learn to recognize and treat clinical shock, first let's talk about a common misperception about shock.

Shock versus Stress Reactions

"Don't worry, he's just in shock," is not something you'll ever hear from a medical professional.  Have you ever experienced something terrifying or traumatic and felt your heart rate increase, started breathing fast, and felt dazed or confused, sweaty, and anxious?  This reaction is quite common but very different from clinical shock.  We can refer to this as an “acute stress reaction” or “psychological shock”.

When we have a traumatic experience, our bodies may react with the “fight or flight” response.  Either the sympathetic nervous system produces adrenaline or the parasympathetic nervous system produces acetylcholine.  This can result in a rapid heart and respiratory rate, sweating, feeling flushed, heightened anxiety, being dazed or confused, inactive, or even a state of stupor.  However, the key difference between an acute stress reaction and clinical shock is the underlying cause.  In shock, something is impairing the body’s ability to circulate oxygenated blood, whereas in an acute stress reaction the body is producing chemicals to respond to a perceived threat.  Acute stress reactions may be severe but will not result in death, whereas clinical shock may progress to death if unrecognized and untreated.

Signs and Symptoms of Shock

As a remote medicine provider, the first step towards treating shock is recognizing it.  Shock isn’t a stand-alone diagnosis, but rather is the result of some other problem.  Any time you have a patient with traumatic injuries, blood volume issues from dehydration or bleeding, signs of sepsis (systemic infection), respiratory problems, or heart trouble, consider the possibility of shock.

Some particular signs and symptoms to look out for are: 

• Cool, clammy skin.
• Pale or ashen skin, lips, nail beds, or mucosal membranes.  
• Rapid pulse and respirations
• Nausea or vomiting
• Weakness or fatigue
• Dizziness or fainting
• Decrease in level of responsiveness or change in mental status

Stages of Shock

Humans are incredible when it comes to staying alive.  When we have a problem that causes shock, our bodies respond by trying to compensate for the problem.  When those compensatory mechanisms are overwhelmed, patient status begins to deteriorate and eventually the shock becomes irreversible and leads to death.  We recognize three stages of shock that reflect this progression:

• Early (compensated) shock:  The body is actively trying to deal with the problem.  Heart rate and breathing rate increase and the body starts to shunt blood away from the extremities towards the core to support the vital organs.  In this phase, blood pressure and mental status generally remain stable.  Depending on the cause and the patient’s health, they may be able to compensate for a very long time, and the interventions you can provide as a Wilderness First Aid provider or WFR will help keep this person alive. 
• Late or decompensated shock:  The body’s efforts to maintain blood pressure start to fail and the patient deteriorates.  Heart rate and respiratory rate may continue to increase but blood pressure begins to drop, and the patient will decline from alert to less responsive.  At this point, the patient needs more significant medical interventions like IV therapy, advanced medications, or possibly whole blood transfusions and/or surgery to recover.  
• Irreversible shock:  As the name implies, there are no medical interventions that can save a patient in irreversible shock.  Level of responsiveness, heart rate and respiratory rate will decline and disappear.  They may exhibit agonal gasping, and eventually will die.

How to Treat Shock in Wilderness or Remote Environments

The first and most important treatment for shock is to address the underlying cause.  If someone isn’t breathing, you may need to clear their airway and/or breathe for them using rescue breathing.  If their heart isn’t beating, pump it for them using CPR skills.  If someone is experiencing severe bleeding, stop the bleeding.  If they are dehydrated and able to swallow and keep down fluids, encourage them to drink for oral rehydration.  If they’ve been exposed to an allergen, remove the exposure and treat the allergic response.  

Some causes of shock we can’t easily fix in wilderness, like internal bleeding, sepsis, or neurological problems.   Regardless of the cause, here are some common treatments you can use for all shock patients:

• Keep them calm. Remember that in shock the patient isn’t getting enough oxygenated blood.  Calming and reassuring the patient can help reduce the demand on their cardiac and circulatory system.
• Keep them warm. Especially in the case of traumatic injuries, reduced body temperature contributes to a cascade of problems with clotting and blood chemistry that eventually results in death.  In remote or wilderness environments, you may not be able to do much about those other problems, but keeping your patient warm should be a huge priority.  
• Support breathing.  Especially if your patient is altered or has a diminished level of responsiveness, maintain an open airway or position of comfort to facilitate easy breathing.
• Raise their legs?  Or not.  For a long time, medical providers used the Trendelenburg (head down, feet up) or modified Trendelenburg (head and back flat, legs elevated) as a supposed treatment for shock.  These positions may help during abdominal surgery and other medical procedures, but research shows that raising the legs neither helps nor hurts the shock patient.  So this is no longer the recommended standard of care.
• Prioritize rapid evacuation.  The shock patient needs advanced medical care as rapidly as possible.  Start the rescue process early, requesting a paramedic or ALS (advanced life support) provider if possible.  Try to get the patient to “definitive care”, that is, the hospital, as soon as possible while keeping them calm, warm, breathing well, and not increasing demand on their heart and lungs.
• Monitor vital signs.  Every five to fifteen minutes, check for any changes in level of responsiveness, heart rate, respiratory rate, skin/tissue color, temperature, and moisture, pupils, and blood pressure if you have a cuff and know how to use it.
• Avoid giving food and water. In an urban context, shock patients shouldn’t have anything to eat or drink because they may be in surgery very soon and stomach contents can complicate anesthesia.  In remote/wilderness settings you’ll have to use your judgement.  You may need to provide oral fluids to help maintain hydration or even snacks during a very long rescue effort.  Try to minimize oral intake as the patient gets closer to the hospital.

Learning More

Now you know what shock is, how it differs from psychological reactions, the causes and types of shock, signs and symptoms of clinical shock, and how to treat for shock in remote or wilderness settings.  It takes additional training to master how to treat all the underlying causes of shock.  The best way to practice and solidify these skills is by taking a two day Wilderness First Aid course or even better, earning the more comprehensive Wilderness First Responder certification.  I hope to see you in a class soon.  Stay safe out there!