Wilderness and Rescue Medicine 8th Edition

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Wilderness and Rescue Medicine

Pressure points on proximal arteries, sometimes mentioned in first aid texts, are generally not effective for life-threatening bleeding. Hemostatic agents (bandages designed to facilitate blood clotting at the bleeding site) remain unproven in actual field use, and anecdotal experience is mixed. However, these products may offer the only viable alternative in treating severe bleeding that is difficult to access, such as axillary and groin injuries and gunshot wounds to the abdomen. To be effective, hemostatic agents must be properly applied or packed into the wound.

pelvic fracture or packing an abdominal wound with gauze (with or without hemostatic agents), may increase the pressure on the bleeding site or reduce the space available for blood to accumulate. This tamponade effect may occur naturally in other confined spaces such as around the kidneys or inside the capsule of the spleen or liver. This fortuitous condition may allow time to evacuate the patient to surgery before shock progresses. There are no definitive ALS field techniques to control severe internal bleeding. In the presence of progressive shock, ALS providers may use IV crystalloids to increase blood volume and main- tain minimal effective perfusion pressure during evacuation. This must be done cautiously because increased pressure can disrupt clot formation, and too much intravenous fluid can impair coagula- tion and contribute to hypothermia. Another ALS option is a drug called tranexamic acid (TXA) which has been shown to reduce hem- orrhage if given soon enough after the injury. It can be administered orally or by IV and works by inhibiting the breakdown of fibrin in clots. It is in use by some EMS systems in the U.S. and elsewhere, particularly where access to surgery and blood replacement products will be delayed. Nevertheless, for uncontrolled bleeding giving IV fluids and TXA in the field is less important than access to a hospital and a surgeon. If the bleeding site is accessible and controlled, IV therapy may help to restore perfusion pressure and is less likely to be harmful. Shock stabilized like this, especially if patient protection and body core temperature is not an issue, becomes a lot less of an emergency. Evacuation can be slower and less hazardous. Brain Failure Changes in mental status or level of consciousness can be caused by direct trauma to the nervous system or by loss of brain oxygenation due to cir- culatory or respiratory system problems. There is no real way to treat brain failure other than to treat the cause. Examples include giving sugar to reverse hypoglycemia or naloxone to reverse opioid overdose. Otherwise, BLS is aimed at

General Principles

Circulatory Failure

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Bleeding Control: • Direct pressure • Tourniquet • Hemostatic agents • Clamps

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© 2018 WMA

General Principles

Circulatory Failure

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Commercial Tourniquets : • Place at least 5cm proximal to wound o Avoid joints o Not effective over bulky clothing • Learn how to apply before you need it • If the tourniquet doesn’t stop bleeding:

o Second tourniquet o Pressure dressing

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© 2018 WMA

No technique for bleeding control will work if you don’t find it. Even profuse external bleeding can be hidden by bulky clothing. This can be a real problemwhen the clothing is waterproof, and the weather is too extreme to permit undressing the patient. A thorough exploration with a gloved hand is a mandatory part of the primary assess- ment of a trauma patient. Internal bleeding is difficult to control without surgery. Some BLS techniques, like binding a