Endotracheal Tube Sizes: A Complete Guide for Adults, Pediatrics, and Neonates

When doctors prepare to intubate a patient, choosing the correct endotracheal tube (ET tube) size is crucial. The wrong size can lead to air leaks, airway trauma, or inadequate ventilation.

This guide explains ET tube size selection, from adults to pediatrics and neonates, along with a quick reference chart.

What Are Endotracheal Tube Sizes?

Endotracheal tubes are measured by their internal diameter (ID) in millimeters. For example, an ET tube size 7.0 mm means the inside diameter is 7 millimeters.

Proper size ensures:

• Effective ventilation

• Reduced risk of aspiration

• Safer intubation and extubation

Adult Endotracheal Tube Sizes

For most adults, the recommended ET tube sizes are:

• Adult males: 7.5 – 8.5 mm ID

• Adult females: 7.0 – 8.0 mm ID

• Special cases (e.g., difficult airway): smaller tubes may be used

Pediatric Endotracheal Tube Sizes

In children, ET tube size is usually based on age and weight. A common formula is:

* Uncuffed ET tube size (mm) = (Age in years / 4) + 4
* Cuffed ET tube size (mm) = (Age in years / 4) + 3.5

Example: A 6-year-old child → (6 / 4) + 4 = 5.5 mm uncuffed tube.

Neonatal Endotracheal Tube Sizes

Neonates and infants require much smaller tubes:

• <1000 g (preterm): 2.5 mm ID

• 1000–2000 g: 3.0 mm ID

• 2000–3000 g: 3.5 mm ID

• >3000 g (full-term): 3.5 – 4.0 mm ID

Endotracheal Tube Size Chart

Cuffed vs Uncuffed Size Selection

• Adults: Cuffed tubes are standard.

• Children: Both cuffed and uncuffed are used, with cuffed becoming more common.

• Neonates: Usually uncuffed to protect delicate airways.

TICARE® Endotracheal Tubes — Complete Size Range

TICARE® offers ET tubes in sizes 2.0–10.0 mm, including both cuffed and uncuffed types. Each tube is:

• Sterile and single-use

• Made with smooth beveled tips for safe intubation

• Equipped with radiopaque lines for X-ray visibility

Explore TICARE® Endotracheal Tubes for adults, pediatrics, and neonates.

FAQs About Endotracheal Tube Sizes

Q1: What is the most common ET tube size for adults?

• 7.5–8.5 mm for men, and 7.0–8.0 mm for women.

Q2: How do you calculate pediatric ET tube size?
Use the formula: (Age / 4) + 4 for uncuffed, or (Age / 4) + 3.5 for cuffed.

Q3: What size ET tube is used in neonates?
Preterm infants may require 2.5–3.0 mm, while full-term newborns usually need 3.5–4.0 mm.

Q4: Why is choosing the right ET tube size so important?
The wrong size can cause air leaks, ineffective ventilation, or damage to the airway.

Final Thoughts

Correct endotracheal tube sizing is essential for safe and effective airway management. Adults typically require 7.0–8.5 mm tubes, pediatrics need age-based sizing, and neonates require very small sizes.

TICARE® provides a full range of endotracheal tubes for adults, children, and neonates, trusted by hospitals and clinics worldwide.