Triage is used in medical emergencies, as a system to sort the injured so that the greatest number of patients can be helped. In medical emergency situations where there are more injured people than there are medical resources to care for them, triage allows doctors or other health care professionals to decide which people can be helped the most, and how to help them efficiently.
Primarily used for battlefield medicine or during disaster situations, triage allows health care professionals to determine which patients require immediate attention to survive, which patients are able to wait, and which patients are beyond help with the limited resources available. Emergency Rooms also triage patients.
The medical personnel on the scene preforming triage move as quickly as possible from patient to patient assessing their situation. Patients with non-life threatening injuries are marked as low priority. Things like broken bones or minor wounds can would fall into this category. Often times, lightly injured patients, sometimes referred to as the "walking wounded", can assist each other with basic first aid and in moving to safety in a dangerous environment such as an accident scene.
Patients who will not survive without immediate medical attention, and are very likely to survive with help are given a high priority. Severe bleeding from wounds, amputation, or internal injury would fall into this category. Basic first aid is not enough to save these patients, but basic surgery will give them a high probability of survival.
Ethically and emotionally, the most difficult aspect of triage is designating some patients as requiring too much attention, or being unlikely to survive even with extreme medical care. The triage professional must make this difficult choice though, because the same four surgeons who would need 10 hours to try and save a victim of severe burns, only to give him a slight chance of survival, may be able to save dozens of less severely wounded patients, and give each of them a very good chance at recovery.
An additional aspect of triage is lowering the pressure on emergency medical units and nearby trauma units by sending lightly wounded and severely wounded but stable patients to other doctors who are more able to handle the load. Instructing lightly wounded patients to see their regular doctor, or sending severely wounded but stable patients to hospitals further away are good examples.
As a method of putting limited medical resources to the most possible good, triage is a necessary tool for health care professionals faced with an emergency situation.