The air is filled with smoke. The rattle of gunfire echoes all around. Helicopters hover overhead. Medical teams race through semidarkness to render assistance in response to the screams of injured soldiers.

The battle is not a real one, but simulated. The action takes place at the Israel Defense Forces' Center for Medical Simulation Center at Tzrifin, near Tel Aviv. It is the largest army training base in the country, and army medical teams from all over Israel come to train at this facility. Teams that include doctors and paramedics are put through their paces to see how they perform under realistic battlefield conditions.

Students experience progressive drills that begin with reinforcement of basic skills, including managing airways and ventilating patients. They use state-of-the-art manikins with built-in mechanisms for simulated breathing. Instructors can regulate the breathing rate by remote control, letting students check it independently.

Instructors can also control the movement of jaws and make it difficult to open the manikins' mouths. This allows simulation of obstructed airways. Pulse oximeters monitor the saturation of oxygen in the bloodstream as well as the pulse. Doctors carry out procedures such as endotracheal intubations. All of this is done risk-free, on manikins that breathe, talk, blink and respond like real patients.

For such professionals, communication is as important as their medical skills. A doctor and his or her paramedics need to focus on seamless teamwork. Paramedics must learn how to coordinate with doctors, each of whom has their own personal working style. Doctors, who sometimes respond on ambulances in the country, need to know the strengths and weaknesses of the members of their paramedic teams. This helps prevent problems later, when the providers work together on the real battlefield. Once this stage is completed, teams move on the next room, where they are presented with a scenario and instructed to start working. Any remaining communication problems are typically resolved at this stage.

The final stage is a multiple-casualty battle scenario, staged in a special room designed to look and feel like a battlefield. Wounded "soldiers" lie on the ground; camouflage netting hangs down, adding to the authenticity. Special effects emanate from mounted speakers: sounds of artillery fire, the staccato crackle of rifles, helicopters hovering and the screams of the wounded. Smoke is introduced into the room for additional effect. The aim of this stage is to test the nerves and efficacy of the providers, gauging their ability to work under the pressure of simulated battle conditions, and not in a clean and quiet environment. A senior paramedic supervises according to standard army procedures.