The War in Ukraine Is Changing How US Troops Train With Tourniquets.

As the US military prepares for high-intensity, mass-casualty future wars, its medics are training to do something they almost never did during the Global War on Terror — remove a tourniquet from a wounded soldier.

Not long ago, tourniquet training for most American service members followed simple, strict guidance: apply one high and tight to limbs to stop life-threatening bleeding, and leave removal to advanced medical care personnel.

A modern military tourniquet is a heavy-duty nylon strap that’s tightly secured around an injured limb with Velcro, then cinched down further by twisting a small rod until blood flow stops.

In the GWOT era, stopping a service member from bleeding out in the field was the top priority, and the possibility of rapid medical evacuation required few further considerations. But in large-scale combat operations, where air control is contested, medics and non-medical troops alike may have to find alternative solutions to prolonged tourniquet use to prevent the kind of catastrophic damage that can result in organ dysfunction or limb loss.

US Army Special Forces training personnel told Business Insider that students in their medical pipeline are increasingly expected to know how to remove them, not just apply them. Troops are graded on those removals, known as tourniquet conversions, and on their ability to teach others to do the same.

“As we’re seeing more battlefield data from modern conflicts without that golden hour, now medics are forced to make a decision themselves as to when and if they reverse that tourniquet,” said the Army’s special operations medical course chief, a trauma expert who spoke to Business Insider on condition of anonymity. “If you don’t, you lose that limb.”

Tourniquets are among the most important lifesaving tools in a medic’s kit, according to the military’s Tactical Combat Casualty Care guidelines, and hemorrhage is the leading cause of preventable death on the battlefield. When in doubt, putting on a tourniquet on a wounded patient remains a safe decision, the chief said.

But the complexity of Ukraine’s battlefields, where pervasive surveillance and attack drones have often made timely casualty evacuation impossible, has shown that isn’t always a hard-and-fast rule.

There, medics are being forced to manage combat casualties for longer, requiring them to find other ways to control bleeding to avoid damage that can come with leaving tourniquets on for too long. Troops in Ukraine have previously told Business Insider that prolonged use has turned injuries that should have been an “easy fix” into life-altering amputations.

When blood flow is restored after prolonged tourniquet use, toxins from the damaged tissue can be released into the bloodstream, potentially injuring the kidneys. Ukraine has reported an increase in demand for dialysis among wounded troops who’ve had tourniquets on for too long. Permanent nerve damage is also a concern.

One of the clearest lessons emerging from Ukraine is the need for more troops to understand tourniquet conversions, said Col. Ken Dwyer, commander of the Army’s Special Warfare Center and School, which oversees the students’ training.

“I put on a tourniquet to save this guy’s life. But at some point, I need to figure out a less destructive way to control that bleeding,” Dwyer said. “I have to remove that tourniquet and see if a pressure dressing will work or something else will work, and to try to save that limb.”

The students, including Navy corpsmen headed to Marine reconnaissance and special operations units and Army medics assigned to the Rangers and Green Berets, are also expected to teach tourniquet conversion to other service members and allied forces, the course chief said. (Navy SEAL and Air Force special operations medics attend separate training pipelines.)

Troops who fought in Iraq and Afghanistan were taught to apply tourniquets, but rarely to remove them — loosening one too soon can restart massive bleeding.

That approach reflected the nature of the wars the US was fighting and its overwhelming air superiority — casualties were often evacuated by helicopter within the military’s “golden hour” to well-staffed trauma centers where surgeons and trauma specialists could safely remove the tourniquet.

Now, casualty evacuation in Ukraine is so difficult and dangerous that ground robots are increasingly being used to evacuate troops, with varying degrees of success. Deploying medical crews for rescue is risky, and helicopter evacuations are usually impossible.

“The duration of a pre-hospital tourniquet has long been a concern,” said John Holcomb, a trauma professor at the University of Alabama who formerly led the Army’s Institute of Surgical Research, and served as a trauma consultant for the Army Surgeon General.

But “it was less of a concern in Iraq and Afghanistan because we had such rapid evacuation, right? We controlled the air.”

After the chaos of combat, he said, casualties arrived at well-lit, robustly staffed medical facilities where providers had the time and resources to reassess tourniquets. Even those that might not have been necessary could be removed quickly enough to avoid complications.

Ukraine has forced military trauma experts to rethink the assumption that casualties will quickly reach advanced care.

“When you don’t control the air, when you have denied, prolonged evacuation, then you put a tourniquet on, if you leave it on for longer than two hours, it can cause more problems than the wound,” Holcomb said.

Stacy Shackelford, an emergency medicine professor and former director of the military’s Joint Trauma System, called the shift a “180” driven by lessons from Ukraine. “Every single person who’s trained to put on a tourniquet needs to also be trained to take off a tourniquet,” she said.