UMEM Educational Pearls

Category: Pediatrics

Title: Pre-term tube sizes

Posted: 4/22/2011 by Mimi Lu, MD (Emailed: 5/6/2011) (Updated: 5/6/2011)
Click here to contact Mimi Lu, MD

Continuing the theme of endotracheal tube size pearls...  You get a box call for a pre-term baby delivered precipitously by mom at home and baby is blue.  EMS is bagging but unable to secure a definitive airway.  What size ETT do you reach for?  If you try to apply the formula "uncuffed ETT = (age/4) + 4", how much smaller than size 4 can you go?

Here's a nice mneumonic about guessing pre-term "tube" sizes.  Please note ETT = uncuffed endotracheal tube size.
20-25 week gestation: 2.5 ETT
25-30 week gestation: 3.0 ETT
30-35 week gestation: 3.5 ETT
35-40 week gestation: 4.0 ETT
Basically, a 25-week neonate gets a 2.5 tube, a 30-week neonate gets a 3.0 tube, etc.  As always, be prepared and have an additional ETT a 1/2 size smaller readily available.