Austere Medicine

Austere Medicine

When Do We Apply the TQ "High and Tight?"

TQ Forearm      There is a lot of discussion on whether to place a tourniquet (TQ) "high and tight" on an arm or leg,  or place 2-3 inches above the wound, even if on the forearm or lower leg, sometimes called a  "double bone compartment. " There is also those who say a tourniquet can be on for 1 hour, or for 8+, so which is it? 

The short answer is, it depends on the wound, who you are, and where you are.

 "When do we do high-and-tight? "

High-and-tight is a "catch all" for most situations and non-medical professionals. It's easy to remember and unlikely to be placed distal (away from the injury, not between injury and heart) or be placed over a joint which would make it ineffective. High and tight also accounts for blast wounds where the wound may be more extensive or deeper than it appears, and when placing over clothes during "Care Under Fire" where the wound and location of bleeding may not be easily apparent.

For non-medics and Tactical Combat Casualty Care (TCCC) trained individuals, high-and-tight is for care-under-fire.

For those close to a hospital, within 1-2 hours, high-and-tight is also fine. We will discuss why if farther away from care you may want to consider other options.

Can we place it on a 'double bone extremity' such as a forearm?" 

Arm

     First, The assumption that a tourniquet wont work on a 'Double Bone compartment' is a myth. It somehow spread that a TQ wont work on the forearm or lower leg because arteries "hide in between the bones." Tourniquets actually work BETTER on these extremities because smaller circumference is inherently easier to compress. To put this in perspective, a man with large legs may likely require two tourniquets, because there is larger circumference to tourniquet ratio. With that same logic, and proven in studies, is forearms and lower legs are easier to compress. If the wrist is squirting arterial blood, you can place 2-3" above wound and be fine, you don't need to put it all the way up on the arm. Either way, stopping the bleeding first is more important.

"Why put a Tourniquet on 2-3 inches above when we could just go high and tight anyway?" 

     If you are within an hour of a hospital, this likely isn't a big deal. You can go high and tight.

However, 

If you're a medic who may sit on a patient for longer than 1-2 hours, especially for 8-12+ hours, intentionally placing 2-3' above is a consideration. On top of your time with the patient, patient may have a long transport with a flight medic (who may not re-assess the tourniquet,) then arrive at hospital  where the nurses and doctors there might not know a lot about tourniquets so they also don't check for compartment syndrome and do not tighten it during the wait time until surgery. This leads to a loose tourniquet causing compartment syndrome and ruining their limb. It's good form to set your patients up for success in case the rare case the tourniquet damages them from being too loose or on for longer than 8+ hours.

"But can't Tourniquets be on for 8+ hours before permanent damage even starts to begin?"

     Yes, If done correctly.

When a tourniquet is properly applied, it can stay on for 6-8+ hours without the patient likely losing the limb. This means it stops BOTH arterial and venous flow.

But if a tourniquet is too loose, it stops veins but not arteries.

Arteries flow TO limbs, veins take blood back to the heart.

     So a loose tourniquet can let blood IN, but not back out so blood stays in the leg and keeps coming. This is a recipe for disaster called "Compartment syndrome." Imagine a highway where cars could get on but never get off, and there is a traffic jam. That is what is happening with your bodies "waste products" and build up of blood in that injured extremity. This can destroy a limb in just a couple hours and be dangerous for the whole patient.

Let's re-cap: Proper tourniquets can be on 6-8+ hours. Loose tourniquets are way worse, so make sure you train hard and re-assess your tourniquets often after application, to make sure bleeding is controlled and there is no pulse on that arm/leg.

That is why some people say tourniquets are safe for 1-2 hours, because even if you mess it up by applying loose, it will at least slow down bleeding instead of fully stop it, they can still be fixed at a hospital in time. Do not let this scare you away from tourniquet use, they save lives. 

"What about those of us 6-8+ hours away from medical help?" 

     It doesn't have to be a far flung battlefield for you to find yourself many hours from help. In adverse weather such as snowstorms, flooding, or even while far away on a hike in the mountains, you can be isolated or far away from help.

If there is a chance this tourniquet will be on for a very long time, and you can easily see where the wound is, then 2-3 inches above is preferable over high and tight. Just ensure it is not on a joint (elbow/knee.) This way, if there is some damage, it's not more than necessary.

For those of you not trekking far from civilization, you can keep doing high and tight.

Medical professionals can consider:

    If you have already placed a tourniquet high and tight, you can place a second tourniquet 2-3" above the wound, fully tighten. Then you can slowly (over 1-2 minutes) release the top one if it's been on for a short period, preferably if you can monitor patient. Re-assess to make sure lower tourniquet is working and move the other tourniquet loosely above the lower in case it is needed. The criteria for this is further explained in the Journal of Special Operations Medicine article below and I recommend looking over it.
Consider placing 2-3" above the wound in the first place to avoid the hassle.

This will save more tissue in the event it is on longer and hopefully give the surgeon more viable tissue. Any medic can apply tourniquets, great medics set their patient up for success at higher levels.

Additionally, some providers may consider converting a tourniquet to a pressure dressing, so packing a wound to control bleeding, then loosening the tourniquet. This is obviously not an option with amputations.

These considerations can be brought up with your medical director and protocols, but are no replacement for them and common sense. Use telemedicine early and often; If compartment syndrome progresses too far you may even have to request permission to perform fasciotomy.

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