Triage comes from the French trier, to sort, a word once used for grading coffee beans and wool. This episode follows how medicine came to sort people instead, starting with the Edwin Smith Papyrus of 17th century BCE Egypt, which divided injuries into those a healer could treat, those to fight with, and those that could not be healed. Under Emperor Maximilian I of the Holy Roman Empire, the sickest soldiers were ordered treated first. Then Baron Dominique Jean Larrey, surgeon-in-chief of Napoleon’s Imperial Guard, sent light horse-drawn flying ambulances onto active battlefields and ordered that the wounded be treated by severity alone, regardless of rank or even which army they fought for.

In World War I Belgian doctor Antoine Depage built a five-tiered evacuation chain, and helicopters in Korea and Vietnam cut the time from injury to hospital care to under two hours. The civilian START system of 1983, Simple Triage and Rapid Treatment, gave responders a fast airway, breathing, circulation, disability and exposure check and the black, red, yellow and green tags. The episode then examines the flaws: undertriage in about 34 percent of US emergency room cases, trauma systems that accept up to 50 percent overtriage, and the utilitarian ethics laid bare when COVID-19 left hospitals without enough ventilators.

• The capillary refill test: pink color returning to a pinched fingernail in under two seconds
• Why green-tagged walking wounded are checked again and again
• Blunt versus penetrating trauma with identical vital signs: about 63 versus 32 percent survival odds
• A child with 98 percent survival odds and an 80-year-old with 8 percent holding the same red tag
• The VIP problem, and the critique that triage scoring penalizes people with poorer baseline health