Why is it called code blue

Seeing more color-coded alerts lately across our units, and it made me wonder: when did “code blue” become the common term, and what’s the actual origin? A preceptor told me in 2010 her hospital used “code 99,” so I’m curious who remembers the shift and why blue stuck.

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We used “code 99” until about 2010, then switched to “code blue” when our system adopted standardized color codes; the origin’s pretty murky, but “blue” spread via ACLS and TV and got cemented by state guides. If you’re curious, check your hospital’s old emergency‑code memos for the switch date — Wikipedia has a decent overview: Hospital emergency codes - Wikipedia. And no, it’s not because the patient turns blue (grim mnemonic); when did your unit make the change?

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And best breadcrumb I’ve seen is it started as 1960s pager shorthand — Bethany Medical Center in Kansas gets cited — , the origin stories don’t all agree. Our system switched in 2010 when the regional hospital association standardized colors, which tracks with your preceptor’s ‘code 99’ note, @golden-vector. If you want the local why, check your Emergency Management/HICS policy archive for the memo that retired the old code.

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