When a soldier is wounded on the battlefield, medics get the call.

Medics are sort of like paramedics or emergency medical technicians (EMTs) in the civilian world — except that paramedics and EMTs are less likely to carry assault rifles or be fired at by enemy forces. When everything goes wrong, soldiers count on the medics to keep them alive until they can be evacuated to a field hospital.

Ninety percent of combat deaths occur before the victims ever make it to a field hospital; U.S. Army medics are dedicated to bringing that number down.

To save wounded soldiers, the medics have to make life or death decisions quickly and accurately. They use Tactical Combat Casualty Care, or TCCC, to guide their decisions. TCCC is a process of treatment endorsed by the American College of Surgeons and the National Association of Emergency Medical Technicians.

First, medics must decide whether to return fire or immediately begin care.

Since the Geneva Convention was signed, the Army has typically not armed medics since they are protected by international law. But, the Iraq and Afghanistan wars have mostly been fought against insurgencies who don’t follow the Geneva Convention and, additionally, medics have had many of their markings removed. Thus, they’ve been armed with rifles and pistols.

When patients come under fire, they have to decide whether to begin care or return fire. The textbook answer is to engage the enemies, stopping them from hurting more soldiers or further injuring the current casualties. Despite this, Army medics will sometimes decide to do “care under fire,” where they treat patients while bullets are still coming at them.

Then, they treat life-threatening hemorrhaging.

Major bleeding is one of the main killers on the battlefield. Before the medic even begins assessing the patient, they’ll use a tourniquet, bandage, or heavy pressure to slow or stop any extreme bleeds that are visible. If the medic is conducting care under fire, treatment typically means a tourniquet placed above the clothing so the medic can get the patient behind cover without having to remove the uniform first.

Now, they can finally assess the patient.

Once the medic and the patient are in relative safety, the medic will assess the patient. Any major bleeds that are discovered will be treated immediately, but other injuries will be left until the medic has completed the full assessment. This is to ensure the medic does not spend time setting a broken arm while the patient is bleeding out from a wound in their thigh.

During this stage, the medic will call out information to a radio operator so the unit can call for a medical evacuation using a “nine-line.” Air evacuation is preferred when it’s available, but wounded soldiers may have to ride out in ambulances or even standard ground vehicles if no medical evacuations are available.

Medics then start treatment.

Medics have to decide which injuries are the most life-threatening, sometimes across multiple patients, and treat them in order. The major bleeds are still the first thing treated since they cause over half of the preventable combat deaths. The medics will then move on to breathing problems like airway blockages or tension pneumothorax, a buildup of pressure around the lungs that stops a soldier from breathing. Medics will also treat less life-threatening injuries like sprains or broken bones if they have time.

Most importantly, Army medics facilitate the evacuation.

Army medics have amazing skills, but patients still need to get to a hospital. Medics will relay all information about the patient on a card, the DA 7656, and the patient will get on the ambulance for evacuation. The medic will usually get a new aid bag and their pack of medical materials from the ambulance. They will then return to their mission on the ground, ready to help the next soldier who might get wounded.