News & Articles

After pulling the trigger, many hunters have eagerly tracked a frothy pink blood trail, eventually coming upon the harvested animal.  A closer look at the animal reveals the bullet has punctured the ribcage and blood has bubbled at the entry site, streaked down the animal’s side, ending in a puddle on the tundra.  This might be considered a good shot, as it resulted in minimal meat being wasted.  However, an animal can live for a time with a punctured lung, so unless you had nice broadside shot that passed through both lungs, you might be in for an even longer pack out.

In the above scenario, the targeted animal was downed by the bullet or broad head that punctured the lung, a condition known in medical terms as an “Open Pneumothorax” or a “Sucking Chest Wound.”  Although an optimal result to have on your harvested animal, in a human it would be life threatening to have a puncture wound to your chest.

In brief, the physiological effect of the puncture wound is quite simple.   The brain of a healthy person is triggered to breathe by a rise in carbon dioxide levels.  As a healthy person inhales, the diaphragm drops and the chest cavity expands, creating a vacuum.  This expansion of the lungs decreases pressure in the lungs and creates a vacuum resulting in fresh air entering the body.  The chest soon contracts, the diaphragm comes up, increasing air pressure inside the lungs, forcing air from the airway.  It is a simple involuntary exchange of air that occurs 12-20 times per minute in most adults.  The respiratory system in general is very inefficient, each breath inhales 21% oxygen and exhales about 16% oxygen.  The body only retains 5% oxygen with each breath.  

If the body suffers a traumatic event that results in an injury from the outside that penetrates through the lung, a new airway is created.  In this case, when the diaphragm drops, the chest expands and air enters the chest cavity through the new hole.  As air enters the new hole in the chest cavity it may not end up in the lungs, but rather in the space between the lungs and the rib cage (pleural space).  At the same time, when exhaling, air is expelled via the new hole outside the body.

If the chest is punctured due to trauma it will begin to collapse, resulting in a pneumothorax (“air in the chest”).  In this case, when the chest expands, air will enter the pleural space (between the chest wall and lungs) through the new hole.  This air prevents the lung from expanding, and the internal pressure in the pleural space eventually collapses the lung.  At the wound site, air is visible bubbling through the blood.

What may cause an open chest wound?

Possible causes of an open chest wound include the obvious, such as a gunshot or arrow puncture to the chest, back or sides.  Falling on a tent stake, sharp willow branches could have the same effect.  Likewise, trauma injuries such as falling on a rock, or rolling the ATV could result in a broken rib that punctures the lung.

TREATMENT:

• Be sure the scene is safe before trying to help.  Whatever injured the person may be a potential hazard to you, as well.
• Quickly look for the entry and exit wound.  Treat the most severe wound first.  Keep in mind the bullet may not have exited out the body; you may see only the entry wound.
• Place your hand (preferably a gloved hand) over any hole in the chest.  This helps prevent passing infection to the victim as well as minimizing risk that you contract any disease.
• Once the hole has been covered with your hand, expose the entry site in order to place an appropriate dressing over the wound.
• The traditional treatment of a sucking chest wound includes covering the wound with an occlusive dressing and taping it down on three sides.  An occlusive dressing is an airtight patch such as petroleum impregnated gauze, part of a plastic bag, aluminum foil, etc.  Only three sides are taped down to create a one-way valve-like effect on the chest wall, only allowing air and blood to escape through the chest wall, not allowing air to enter into the chest cavity.  The dressing should extend at least two inches beyond the wound on all sides.  The open side of this bandage should be on the downhill side of the victim.
• Consider the possibility that the victim may have a spinal injury.  If a spinal injury is suspected, or if a significant mechanism of injury exists, make sure the head, neck and spine are kept in line.
• Allow the victim to find their most comfortable position to rest.  However, laying them on their injured side, allowing the non-injured lung to work as effectively as possible, is best.
• Activate emergency medical services or search and rescue depending on your location.
• Continue to monitor and protect the victim’s airway, breathing, and circulation. Do a thorough patient assessment, including looking for other bleeding, broken bones, etc.
• Do not make this victim move.  They should be evacuated.
• If rescue is anticipated, do not allow them to eat or drink, as they will be in surgery soon.  If rescue is delayed by a day or two, hydration and caloric intake remain important.

Next time you are following a frothy pink blood trail you can remember to take note of how the blood bubbles at the wound site.   You will be witnessing a sucking chest wound.