Tochen's Formula: Neonatal Endotracheal Tube Depth, Explained | Pediatric Anesthesia Concepts

Got something to say to this podcast? Send a voicemail, and you might hear yourself on the next episode! Tochen's Formula: Neonatal Endotracheal Tube Depth, Explained | Pediatric Anesthesia Concepts A term newborn's entire trachea is about four centimeters long — shorter than your thumb — and the tube tip has to stop in the middle of it, below the vocal cords and above the point where the airway splits to the two lungs. That leaves a safe window measured in millimeters: an error of a single centimeter drives the tip down a mainstem bronchus, ventilating one lung, or back up through the cords and out. Tochen's formula is the elegant answer to that narrow target: the depth to insert an oral tube, measured at the lip, is simply the infant's weight in kilograms plus six. This episode covers — the single 1979 study, how to use Tochen's formula to get it right on the first attempt, required confirmations and primary checks, updates to the Neonatal Resuscitation Program guidelines, and how it relates to everyday practice. Key Takeaways: Tochen's formula is the elegant answer to that narrow target: the depth to insert an oral tube, measured at the lip, is simply the infant's weight in kilograms plus six. It pairs naturally with the vocal-cord depth marker many neonatal tubes carry Goal: you want it mid-trachea, around the first or second thoracic vertebra on an X-ray, halfway between the cords and the carina. Confirm with symmetric chest rise, listen for equal breath sounds in both axillae, look for a sustained capnography trace, and get an X-ray. Neonatal Resuscitation Program's 7th edition in 2016 stepped back from weight-plus-six as its primary method, adopting instead a gestational-age insertion-depth table and the nasal-tragus length. Timestamps 00:00 — The narrow landing strip 02:12 — The 7-8-9 rule 03:04 — Trachea length to body weight 03:34 — Primary tube confirmation 03:52 — Head-dependance link 04:33 — A single 1979 study 06:06 — From Theory to Practice 07:35 — Know where the rule frays 08:46 — An emblem of good Pediatric practice If this made something click, leave a 5-star rating and follow the show. That's how other anesthesia providers — residents, SRNAs, SAAs, CRNAs, and anesthesiologists — find it. New episodes twice a week/