You have been skinning for hours and you've finally reached the zone you're going to ski. Your best buddy crashed hard through the rocks, his leg is deformed and you notice heavy pulsitile bleeding, he passes out and you cannot feel a pulse in his foot. Now what?
Tourniquets are an important tool to have in your back pocket when in the backcountry. Lets talk about how they work, when to use them, and important principles behind their use and damage they can potetially cause.
How Tourniquets work:
A good tourniquet is wide and stiff, and strong. Most backcountry skiers/boarders/snowmobilers have what it takes in their kit to make a tourniquet if a formal tourniquet is not available. An example of a military style trouniquet can be found here. Other, more simple tourniquets are found here. Other things that can be used are voile straps, ski strap webbing with a sincher, etc.
Tourniquets are circumferential and cut off all blood supply to the extremity distal to it when applied. This is a good thing to stop the bleeding on a large blood vessel, however it is bad for the rest of the tissue which now has no blood supply.
When to use a tourniquet:
Because a tourniquet cuts off ALL blood supply in the limb, it is not ideal, and should not be applied unless bleeding cannot be stopped by direct pressure.
FIRST: Apply direct pressure to heavy bleeding. First step, apply direct pressure to the affected area with your finger, slightly closer to the person's body from the bleeding site. You would be amazed at how heavy of a bleed can be stopped by direct pressure for 10-20 mins of direct pressure.
If direct pressure does not stop the bleeding or the patient has mulitple bleeding sites and you are in an unsafe location, apply a tourniquet high on the thigh or on the arm as close to the torso as possible and reevaluate the wounds as soon as you are safe and it is appropriate.
Apply the tourniquet as close to the wound as possible, between the wound and the patient's heart. Synch the tourniquet tight enough so the blood flow stops.
Recheck the wound every 10 mins if you are safe or if you are in an evacuation situation recheck the wound by loosening the tourniquet every hour or so. If there is no active bleeding on recheck, continue to monitor without the tourniquet, if there is active bleeding, tighten the tourniquet only as much as it takes to stop the bleeding.
Do not release the tourniquet if the patient is in a shock state.
Keep the tourniquet in place if bleeding persists without it. There are concerns about damage to the area with the tourniquet so less than 1 hr is ideal for a tourniquet to be on, however in medical literature suggests that a tourniquet has been applied for up to 16 hrs without damage as noted in this case report.