Edinburgh, Ind. -- The room is dark, lit only by a small flame left over from an explosion. Through the thick smoke, two Soldiers quickly enter and begin administering aid to several casualties thrown to the floor. In the background, gunfire continues to add to the already overwhelming situation as the casualties groan and call out for help.

Reserve Soldiers with the 2-340th Training Support Battalion, 157th Infantry Brigade, First Army Division East, recently rounded out their two-week annual training by taking advantage of the Medical Simulation Training Center at Camp Atterbury Joint Maneuver Training Center, Ind. First Army Division East brigades are comprised of both active duty and reserve battalions.

Already certified as combat lifesavers, more than 20 Soldiers participated in a one-day combat lifesaver refresher training.

"Here at the MSTC, we teach the plan or the system Soldiers use to take care of casualties. We teach, specifically, to treat the most preventable deaths on today's battlefield: bleeding, upper airway obstruction and tension pneumothorax," said Thomas Deen, MSTC instructor and a course designer.

"We can look at battlefield care in three phases," Deen continued.

Phase one care occurs when Soldiers are under fire. In a critical situation, Soldiers must address the most life threatening condition-- bleeding to death -- with a proper tourniquet only.

Phase two or tactical field care occurs when the victims' condition become reasonably safe, often times with a secured perimeter or after combat has moved further away.

"It's at this point we can now check over our casualty from head to toe using
'H-A-B-C,' explained Larry Purlee, also an instructor and course designer at the MSTC.

"Hemorrhage control of a critical wound can save the lives of up to nine percent of battlefield causalities," said Purlee.

Clearing an obstructed airway--or the "A" in H-A-B-C, is next. Monitoring the breathing of the casualty follows with a closer look at chest movement, and then addressing any circulation or other bleeding concerns is the "C" in H-A-B-C.

In Phase three Soldiers prepare to move casualties from the battlefield.

At the end of classroom instruction, Soldiers, broken into teams of two, move through the trauma rooms for evaluation.

The instructors set the scene: an explosion in a building with several casualties. Soldiers are told the area is reasonably secure although there are sounds of gunfire in the background, and the room is dark and smoke filled. A 360-degree camera system records the action of the combat lifesavers.

As the Soldiers enter a room they see five casualties, highly sophisticated medical simulators.

"These simulators blink, breathe, bleed, have a pulse, and blood pressure, and can make voice-recorded noises," said Purlee.

Three of the casualties have visible injuries but are not breathing and have no pulse. In addition to properly treating a casualty, part of the evaluation includes observing. The combat lifesavers quickly assess which casualties to treat.

"I know I'm trained as a combat lifesaver, but this course is really awesome and realistic. The instructors were right with us all the way through the simulation," said Sgt. 1st Class Dave King, trainer / mentor, 157th Infantry Brigade, First Army Division East.

"Even following our team's plan on how to treat a casualty, I still made some mistakes," admitted King.

"We were taught to check all four limbs to evaluate for any bleed outs. My side had an arm and leg, and I said it was good. The instructor said to check again, so I felt through the pants and realized that part of the casualty's leg was missing and would have bled out," King continued.

It is a good lesson in understanding how each individual combat lifesaver reacts under stressful situations, King said.

"We have found that Soldiers won't make the same mistake again even though the environment is overwhelming," said Purlee.

"My biggest take away, as a trainer / mentor, is that we spend a lot of time teaching in the classroom, but to actually go through it and act immediately under stress really brings out our strengths and weaknesses. As trainer / mentor, we need to ensure that we make teaching and training mobilizing Soldiers is as realistic as possible," said King.

After the instructor ends the exercise everyone comes back and conducts a critical after action review. Recording the exercise allows both instructor and student a more objective evaluation. The Soldiers said they were eager to go through the simulation again.

"It's a good lesson learned. All Soldiers should be a subject matter expert on applying a tourniquet…it's been proven time and time again to save lives on the battlefield," said Deen.

The next group of combat lifesavers enters the room. A Soldier moves to the first casualty and begins to recite, "H -- A --B -- C." The instructor smiles, he is on the right track.