MCI guides

Triage sieve and sort explained

At a mass casualty incident there are more patients than people to treat them. Triage decides who gets help first. Most services use two stages: a fast sieve at the scene, then a closer sort at the casualty clearing station.

This guide is general information for trained responders. Follow your own service's protocols and local rules, which may differ.

The categories

• P1 (red): immediate. Life threatening, needs treatment now.
• P2 (yellow): urgent. Serious, but can wait a short while.
• P3 (green): delayed. Walking wounded, minor injuries.
• Dead: not breathing after the airway has been opened.

The triage sieve, step by step

The sieve takes under 30 seconds a patient. You do not treat, apart from opening the airway and stopping catastrophic bleeding.

• Can they walk? Yes: P3. Move them to one place.
• Are they breathing? No: open the airway once. Still not breathing: dead. Breathing now: P1.
• Breathing rate. 9 or fewer, or 30 or more a minute: P1.
• Circulation. Pulse over 120, or capillary refill over 2 seconds: P1.
• Everyone else: P2.

Put a tag on every patient, even the walking ones. A tag number means the patient can be tracked from the scene to the hospital.

The triage sort

The sort happens once patients reach the casualty clearing station and there are more hands. It is slower and uses measured vital signs. A common method is the Triage Revised Trauma Score, which scores three things from 0 to 4:

• Breathing rate: 10 to 29 scores 4, over 29 scores 3, 6 to 9 scores 2, 1 to 5 scores 1, none scores 0.
• Systolic blood pressure: 90 or more scores 4, 76 to 89 scores 3, 50 to 75 scores 2, 1 to 49 scores 1, none scores 0.
• Glasgow Coma Scale: 13 to 15 scores 4, 9 to 12 scores 3, 6 to 8 scores 2, 4 to 5 scores 1, 3 scores 0.

Add the three scores. 12 is P3, 11 is P2, 1 to 10 is P1, and 0 is dead.

Re-triage

Patients change. A P2 can become a P1 while waiting for transport. Check again whenever you can, and update the tag and the record so the incident commander sees the change.

Common mistakes

• Stopping to treat during the sieve. Keep moving.
• Not counting the walking wounded. They still need a tag and a destination.
• Paper tags that never reach command. The commander needs the numbers in real time.