Category Archives: Medical


Photo by PM3 John DeCoursey

To Do Today:

Drowning is suffocation by liquid. It can lead to death and ongoing health problems. A drowning victim inhales water into the lungs or the throat closes by reflex so that little or no water can enter the windpipe. In either case, a victim can no longer breathe.

Drowning itself is quick and silent, although it may be preceded by distress which is more visible. A person drowning is unable to shout or call for help, or seek attention, as they cannot obtain enough air. The “instinctive drowning response” is the final set of autonomic reactions in the 20 – 60 seconds before sinking underwater, and to the untrained eye can look similar to calm or safe behavior. Persons trained in rescue learn to recognize drowning people by watching for instinctive movements in two categories:

Distress: People in trouble, but who still have the ability to keep afloat, signal for help and take actions.

Drowning: People suffocating and in imminent danger of death within seconds. This includes:

    • Passive drowning: People who suddenly sink or have sunk due to a change in their circumstances. Examples include people who drown in an accident, or due to sudden loss of consciousness or sudden medical condition.
    • Active drowning: People such as non-swimmers and the exhausted or hypothermic at the surface, who are unable to hold their mouth above water and are suffocating due to lack of air. Instinctively, people in such cases perform well known behaviors in the last 20–60 seconds before being submerged, representing the body’s last efforts to obtain air. Notably such people are unable to call for help, talk, reach for rescue equipment, or alert swimmers even feet away, and they may drown quickly and silently close to other swimmers or safety.

Drowning begins at the point a person is unable to keep their mouth above water; inhalation of water takes place at a later stage. As mentioned, drowning can be quick and unspectacular and media depictions as a loud, violent struggle have much more in common with distressed non-swimmers who may well drown but have not yet begun. In particular, an asphyxiating person is seldom able to call for help. The Instinctive Drowning Response covers many signs or behaviors associated with drowning or near-drowning:

  • Head low in the water, mouth at water level
  • Head tilted back with mouth open
  • Eyes glassy and empty, unable to focus
  • Eyes open, with fear evident on the face
  • Hyperventilating or gasping
  • Trying to swim in a particular direction but not making headway
  • Trying to roll over on the back to float
  • Uncontrollable movement of arms and legs, rarely out of the water.

Other warning signs drowning is that the victim may call for help and has an expression of dread or panic. But typically a victim that is active and drowning may not call for help because he is trying to conserve his air and will not speak. Another symptom of drowning is when the victim thrashes at the water’s surface. If the victim stops or grows calmer, he has likely been overcome by fatigue, hypothermia, or a lack of air. At this stage, the victim usually has 20 to 60 seconds before going under the water’s surface.

Drowning can also happen in ways that are less well known:

  • Deep Water Blackout. Caused by latent hypoxia upon ascent from depth, where the partial pressure of oxygen in the lungs under pressure at the bottom of a deep free-dive is adequate to support consciousness but drops below the blackout threshold as the water pressure decreases on the ascent. It usually strikes upon arriving near the surface as the pressure approaches normal atmospheric pressure.
  • Shallow Water Blackout. Caused by hyperventilation prior to swimming or diving. The primary urge to breathe (more precisely: to exhale) is triggered by rising carbon dioxide (CO2) levels in the bloodstream. The body detects CO2 levels very accurately and relies on this to control breathing. Hyperventilation artificially depletes this, but leaves the diver susceptible to sudden loss of consciousness without warning from hypoxia. There is no bodily sensation that warns a diver of an impending blackout, and victims (often capable swimmers swimming under the surface in shallow water) become unconscious and drown quietly without alerting anyone to the fact that there is a problem; they are typically found on the bottom.
  • Secondary drowning. Inhaled fluid can act as an irritant inside the lungs. Physiological responses to even small quantities include the extrusion of liquid into the lungs (pulmonary edema) over the following hours, but this reduces the ability to exchange air and can lead to a person “drowning in their own body fluid.” Certain poisonous vapors or gases (i.e., burning fuel, toxic materials, or chemical vapor on/near the water surface), or vomit can have a similar effect. The reaction can take place up to 72 hours after a near drowning incident, and may lead to a serious condition or death.


If the victim is not breathing, begin rescue breathing. Place the victim on his back, tilt head back to open airway, pinch the nose, and give two full breaths. If the victim does not inhale during the first two breaths, reposition his head and attempt two more breaths. Check for a pulse. If a pulse is present, but the victim is still not breathing, continue rescue breathing. If a pulse is not present, begin CPR. WARNING: If the victim has no pulse and is not breathing, administer CPR immediately. If the victim does have a pulse but is not breathing, give rescue breathing only. If the victim has a pulse and is breathing, DO NOT give CPR—CPR could prove fatal. Continue first aid until medical help arrives. A victim who is not breathing and has no pulse may appear dead. DO NOT decide that death has occurred. Continue with the prescribed treatment.


Information contained on this website is for general information and educational purposes only. Please refer to our Disclaimer and Terms and Conditions before attempting any technique described herein.


092014 Skydive

To Do Today:

  • PT – 2hrs cross train
  • Review your respective Body Composition Standards (WSSI, NSW, etc.). Be within standards, or journal a plan to be.
  • Find something to swim in. We are jumping into water survival and drown-proofing next week.

What gets measured, gets managed. Excess body fat hinders athletic performance. This link to the DHHS/CDC describes BMI, with additional links to personal fitness calculators and medical references.



To Do Today:


Hypothermia, frostbite, and trench/immersion foot are the most popular cold injuries for students during the winter. Photokeratitis (snow blindness) will be covered sometime later as it usually occurs during sunny summer months. Please make sure to read the notes on carbon monoxide poisoning at the end of the post.


A common belief that extremely cold temperatures are needed for hypothermia to occur is not true as most cases occur when the temperature is between 30 and 50 degrees Fahrenheit.

Simply, hypothermia occurs when heat loss from the body exceeds the body’s ability to produce heat. Contributing factors include:

  • Air temperature
  • Ambient temperature
  • Wind chill
  • Wet clothing
  • Cold water immersion
  • Improper clothing.
  • Exhaustion.
  • Alcohol intoxication, nicotine and drugs such as barbiturates and tranquilizers.
  • Injuries. Those causing immobility or major bleeding, major burn and head trauma.

Signs and symptoms

The number one sign to look for is altered mental status; that is, the brain is literally getting cold. These signs might include confusion, slurred speech, strange behavior, irritability, impaired judgment, hallucinations, or fatigue.

As hypothermia worsens, victims will lose consciousness and eventually slip into a coma.

Shivering. Remember that shivering is a major way the body tries to warm itself early on, as it first begins to get cold. Shivering stops for two reasons:

  • The body has warmed back up to a normal temperature range.
  • The body has continued to cool. Below 95F shivering begins to decrease and by 90F it ceases completely.

Obviously, continued cooling is bad. So if a victim with whom you are working, who was shivering, stops shivering, you must determine if that is because he has warmed up or continued to cool.

A victim with severe hypothermia may actually appear to be quite dead, without breathing or a pulse. However, people who have been found this way have been successfully “brought back to life” with no permanent damage. The body of those who expire from hypothermia will exhibit a temporary warmth of the skin. So remember, you are not dead until you are warm and dead.

Prevention. Prevention is always better (and much easier) than treatment.

  • Cold weather clothing must be properly warm and cared for.
  • Keep your clothing as dry as possible.
  • If your feet are cold, wear a hat. Up to 80% of the body’s heat can escape from the head.
  • Avoid dehydration. Drink 6 – 8 quarts per day.
  • Eat adequately.
  • Avoid extreme fatigue and exhaustion.
  • Increase levels of activity as the temperature drops. Do not remain stationary when the temperature is very low. If the tactical situation does not permit moving about, perform isometric exercises of successive muscles.
  • Use the buddy system to check each other for signs/symptoms of hypothermia.

Treatment of Hypothermia

  • Make the diagnosis.
  • Prevent further heat loss.
  • Remove the victim from the environment (i.e., into a shelter).
  • Insulate the victim.
  • Rewarm the victim by zipping two sleeping bags together. Pre-warm the bag by using the body heat of another. Place the victim in the bag with two stripped companions inside the bags on both sides of the victim (insert dirty jokes and snide remarks here).
  • Medevac if possible.

Other Points to Remember

  • Fluids. If the victim is mildly hypothermic, give hot/wets.
  • If worse than mild, give him/her nothing by mouth.
  • Avoid, if possible, excessive movement of the victim, as his/her heart may actually stop beating if it is jarred.
  • Major Wounds. Apply first aid to major wounds first, before attempting to re-warm the victim. Re-warming a victim who has bled to death does little good.
  • Never give alcohol to hypothermia victims.
  • Even after you have started re-warming a victim, he/she must be constantly monitored. Don’t forget about the victim.


Frostbite is the actual freezing of tissues. When in a survival/SERE situation, rewarming a severe frostbitten area may not help. It is best to be vigilant of your situation prior to showing signs of frostbite as frostbite is a somewhat preventable injury, even in a desperate situation. It is critical, once frostbite has occurred, that you seek medical attention.

  • Dress in layers. Keep comfortably cool. If you begin to become uncomfortable, add layers.
  • Keep clothes dry. If clothing (especially socks and gloves) become wet, change them. This may mean you have to change sock 4-5 times a day.
  • Dress properly. If the wind is blowing, wear the correct protective layer.
  • Avoid dehydration. When dehydrated, the amount of blood available to warm your fingers and toes goes down, increasing the risk of frostbite.
  • Try to avoid starvation. Remember – food is fuel – and the body uses that fuel to make heat.

Signs and Symptoms

  • Ears, nose, fingers and toes are affected first.
  • Areas will feel cold and may tingle leading to….
  • Numbness which progresses to…
  • Waxy appearance with skin stiff and unable to glide freely over a joint.


  • Frostbite is classified into three different degrees: Frosting, Superficial Frostbite, and Deep Frostbite.
  • Frosting will revert to normal after using the technique of body heat rewarming. Hold the affected area, skin to skin for 15 minutes. Rewarm face, nose, and ears with hands. Rewarm hands in armpits, groin or belly. Rewarm feet with mountain buddy’s armpits or belly.
  • If affected area cannot be rewarmed in 15 minutes, Superficial Frostbite or Deep Frostbite is suspected. Do not attempt to further rewarm. Splint the affected area. Protect the affected area from further injury. Medevac as soon as possible. DO NOT RUB ANY COLD INJURY WITH SNOW. Do not massage the affected area. Do not rewarm with stove or fire: a burn injury may result. Loosen constricting clothing. Avoid tobacco products.

Any frostbite injury, regardless of severity, is treated the same – evacuate the casualty and re-warm in the rear. If not possible, find shelter and seek friendly indigenous medical care. If the tactical/survival situation prohibits evacuation, no consideration should be given to re-warming frostbite in the field. The reason is something-called freeze – thaw – re-freeze injury.

Freeze – Thaw – Re-freeze injury occurs when a frostbitten extremity is thawed out, then before it can heal (which takes weeks and maybe months) it freezes again. This has devastating effects and greatly worsens the initial injury.

In an extreme emergency it is better to walk out on a frostbitten foot than to warm it up and then have it freeze again. Also:

  • Treat frozen extremities as fractures – carefully pad and splint.
  • Treat frozen feet as litter cases.
  • Prevent further freezing injury.
  • Do not forget about hypothermia. Keep the victim warm and dry.

Once in the rear, a frostbitten extremity is re-warmed in a water bath, with the temperature maintained at 101F – 108F.


Trench foot / immersion foot is a cold-wet injury to the feet or hands from prolonged (generally 7 – 10 hours) exposure to water at temperatures above freezing.

Signs and Symptoms. The major symptom will be pain. Trench foot is an extremely painful injury. Trench foot and frostbite are often very difficult to tell apart just from looking at it. Often they may both be present at the same time. Signs include:

  • Red and purple mottled skin.
  • Patches of white skin.
  • Very wrinkled skin.
  • Severe cases may leave gangrene and blisters.
  • Swelling.
  • Lowered or even absent pulse.
  • Trench foot is classified from mild to severe.

Prevention. Avoiding trench foot/immersion foot is aimed simply at preventing cold, wet and immobile feet (or hands).

  • Keep feet warm and dry.
  • Change socks at least once a day. Let your feet dry briefly during the change, and wipe out the inside of the boot. Sock changes may be required more often.
  • Exercise. Constant exercising of the feet whenever the body is otherwise immobile will help the blood flow.

Treatment. All cases of trench foot must be evacuated. It cannot be treated effectively in the field.

While awaiting evacuation:

  • The feet should be dried, warmed, and elevated.
  • The pain is often severe, even though the injury may appear mild; it may require medication such as morphine.
  • In the rear, the healing of trench foot usually takes at least two months, and may take almost a year. Severe cases may require amputation. Trench foot is not to be taken lightly.



Cold environments probably mean you will spend time inside some sort of shelter and have some sort of fire or other heat source. It is critical you have airflow and fresh air built into your setup. Carbon Monoxide is no joke.

Carbon Monoxide (CO) is a heavy, odorless, colorless, tasteless gas resulting from incomplete combustion of fossil fuels. CO kills through asphyxia even in the presence of adequate oxygen, because oxygen-transporting hemoglobin has a 210 times greater affinity for CO than for oxygen. What this means is that CO replaces and takes the place of the oxygen in the body causing Carbon Monoxide poisoning.

Signs/Symptoms. The signs and symptoms depend on the amount of CO the victim has inhaled. In mild cases, the victim may have only dizziness, headache, and confusion; severe cases can cause a deep coma. Sudden respiratory arrest may occur. The classic sign of CO poisoning is cherry-red lip color, but this is usually a very late and severe sign, actually the skin is normally found to be pale or blue.

CO poisoning should be suspected whenever a person in a poorly ventilated area suddenly collapses. Recognizing this condition may be difficult when all members of the party are affected.

Treatment. The first step is to immediately remove the victim from the contaminated area.

  • Victims with mild CO poisoning who have not lost consciousness need fresh air and light duty for a minimum of four hours. If oxygen is available administer it. More severely affected victims may require rescue breathing.
  • Fortunately, the lungs excrete CO within a few hours.

Prevention. Ensure there is adequate ventilation when utilizing a fire or other chemical/mechanical heat source near your shelter.