In times of crisis, there can be many casualties and victims. For those who need medical attention right away, they are sometimes in a state where they are unable to walk and so must be carefully brought out of wherever they are and taken to a hospital. This type of scenario will have many variables which will affect how the transportation will be done. Variables such as extent of injuries, location, terrain, etc. all play a part in how to safely remove a victim from the area.
Typically, a stretcher is what is employed to get the job done. It is a stiff, bed-like apparatus that must be carried by two people in order to carry a patient on it. They are useful as they allow for passage over uneven terrain and can be easily deployed and carried (when empty).
If there is pavement or flat walking surfaces, a gurney (or wheeled stretcher) is preferred. This is what you typically see at the sight of car accidents. They don’t require lifting (except to get the patient onto it in the first place) and make transportation easy.
If you have stairs to cover, then a stretcher or gurney will not suffice. In this situation, you will need a stair chair. It is a wheeled chair with handles positioned in such a way that it can be easily carried down stairs by two people with a patient sitting atop it. It can be very dangerous to try to move someone down flights of stairs without this device, for both the patient as well as the rescuers.
Having the right equipment for the task at hand is a big part of medical rescue. The lack of it can mean failure in the endeavor to save someone from a crisis.