Wilderness and Rescue Medicine 8th Edition

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Wilderness and Rescue Medicine

the tourniquet to a pressure dressing the less risk of ischemic damage there is. If you attempt to convert and are confronted with unmanageable bleeding, there may be no choice but to leave the tourniquet in place. After 6 hours of continuous application, a tourniquet should be left in place until definitive care is reached. This is, in part, because the accumula tion of cellular debris and toxic substances in the limb due to prolonged ischemia can damage vital organs if allowed to enter the general circulation. In long term use, a tourniquet becomes a high risk treatment for a high-risk problem. Urgent evacuation or remote medical advice is indicated. You may have read about using pressure points on proximal arteries as an alternative to direct pressure or a tourniquet. Unfortunately, this tech nique is not effective for life-threatening bleeding. Another well-advertised alternative is hemostatic dressing designed to facilitate blood clotting at the bleeding site. These products remain unproven in actual field use but may offer the only viable alter native 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 packed into the wound and backed up with a pressure dressing. Internal bleeding is difficult to control without surgery. Some field techniques, like binding a 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 accu mulate. This is called tamponade effect and may occur naturally in confined spaces such as around the kidneys or inside the capsule of the spleen or liver. Tamponade of internal bleeding, whether performed by you or occurring naturally, may allow time to evacuate the patient to surgery before shock progresses. In the presence of progressive shock, ALS pro viders may use IV crystalloids to increase blood volume to help maintain minimal effective per fusion pressure during evacuation. Vasopressors such, as epinephrine, can also be used in small doses to increase blood pressure. All of this must be done cautiously because increased pressure can

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

The tourniquet material must be wide enough to avoid crush injury to the healthy tissue under neath (2.5 to 5 centimeters). One inch climbing webbing, or a sail tie would be adequate if you can make it tight enough. Whatever you use for a tourniquet, it is best applied about 5 centimeters proximal to the bleeding site. If you don’t have time to find the site, you can apply it high on the extremity and move it later. Do not apply a tourniquet over a joint. If your tourniquet is working properly, you will be causing complete ischemia. We know that ischemia will eventually lead to infarction, which is why first aid training has historically referred to tourniquet use as “sacrificing the extremity to save the life”. Fortunately, this sacrifice is rarely necessary. A tourniquet can be left in place for approximately six hours with limited tissue dam age and a salvageable limb. However, this does not mean that you should set a reminder for 6 hours and forget it. The sooner you can convert