NRP 9th Edition · Airway

Neonatal ETT Size & Depth

Endotracheal tube inner diameter (Table 5-1) and tip-to-gum insertion depth by gestational age (Table 5-3).

Weight

Gestational age

weeks

Table 5-1 — ETT & suction catheter

Weight	GA	ETT (mm ID)	Suction (F)
< 800 g	22–25 wk	2.5*	5 or 6
800–1,200 g	26–28 wk	2.5	6 or 8
1,201–2,200 g	29–34 wk	3.0	8
> 2,200 g	> 34 wk	3.5	8

*A 2.0-mm ID tube (optional) may be considered for extremely preterm infants.

Table 5-3 — depth by GA (tip-to-gum)

GA	Depth	Approx. weight
23–24 wk	5.5 cm	—
25–26 wk	6.0 cm	700–800 g
27–29 wk	6.5 cm	900–1,000 g
30–32 wk	7.0 cm	1,100–1,400 g
33–34 wk	7.5 cm	1,500–1,800 g
35–37 wk	8.0 cm	1,900–2,400 g
38–40 wk	8.5 cm	2,500–3,100 g
41–43 wk	9.0 cm	3,200–4,200 g

Recommended ETT

—mm

—cm

0246810 cm

Nasal-tragus length (NTL) method — optional

cm, measured

Insertion depth (NTL + 1 cm)—

Confirm placement

AuscultationEqual breath sounds, both axillae

CO₂ detectorColorimetric or capnograph

Final confirmationChest radiograph if remaining in place

Laryngeal Mask Airway (LMA)

Standard devices: validated for infants weighing 2–5 kg. No instruments or vocal cord visualization required.

Smaller infants: LMAs for infants < 2 kg exist, but the lower weight limit for successful insertion is not established.

Use as rescue airway when face-mask ventilation fails and intubation is unsuccessful or not feasible.

Clinical decision support only. ETT sizing (Table 5-1) and insertion depth (Table 5-3) from NRP 9th Edition (AAP/AHA). Confirm depth by auscultating equal breath sounds; obtain a chest radiograph for final confirmation if the tube remains in place. PediaSuite is not affiliated with the AAP or AHA.

Reviewed by C. A. Leyva, MD, neonatologist · Last reviewed September 2026

References

American Academy of Pediatrics, American Heart Association. Textbook of Neonatal Resuscitation. 9th ed. Itasca, IL: American Academy of Pediatrics; 2025. Lesson 5: Endotracheal Intubation, Tables 5-1 and 5-3.
Lee HC, Strand ML, Finan E, et al. Part 5: Neonatal Resuscitation: 2025 American Heart Association and American Academy of Pediatrics Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2025;152(16 Suppl 2):S385–S423. doi:10.1161/CIR.0000000000001367

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