Calculate ET tube size

Pediatric Advanced Life Support (PALS) teaches a formula to calculate the size of endotracheal (ET) tube you need for orotracheal intubation in children, says Carolynn Zonia, DO, FACEP, ED education director at St. Francis Hospital in Evanston, IL.

"Take the age in years divided by 4, plus 4," Zonia explains. (Or, to arrive at the same number, take the age in years plus 16, divided by 4.)

Double that number to determine the Foley catheter tube size and orogastric tube size, she says. Double that number to determine the average size of chest tube to insert, she says. (You can arrive at that same number by multiplying the first number by 4, she explains.)