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    Pediatric Endotracheal Tube (ETT) Size

    Estimates ET tube size based on age.
    When to Use
    Why Use

    Broselow tape or other pediatric emergency management aid not available and child requires intubation.

    Pediatric airways obviously grow with age; it is critical a properly-sized tube is inserted during intubation.



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    Next Steps
    Creator Insights


    • Ventilator settings are always required after intubation but are beyond the scope of this rapid information:
      • Tidal volume in pediatrics is often set 6-8mL/kg
      • Respiratory rate is often set 25-40 breaths / minute
      • FiO2 is often started at 1.0 (100%)
    • Post-intubation care also typically includes:
      • Chest x-ray to confirm tube placement
      • Medications for sedation and analgesia
      • Elevation of the head of the bed
      • NG tube to decompress the stomach
      • ABG after 15-30 minutes after to assess oxygenation and acid-base status


    Predicted Size Uncuffed Tube = (Age / 4) + 4

    Predicted Size Cuffed Tube = (Age / 4) + 3

    Facts & Figures

    This formula typically is applicable to children ages 1-12. Below that, consider an endotracheal tube reference card; above 12, typically most adult sizes (6.5-8.0) can be used.

    Dr. Narendra Singh

    About the Creator

    Narendra Singh, MBBS, FRCPC, is the Chief of Staff at the Humber River Regional Hospital in Toronto, Ontario and the Doctors Hospital at Renaissance in Texas. Dr. Singh completed pediatric training at the University of Western Ontario and a fellowship in pediatric critical care at the Hospital for Sick Children and the Children’s Hospital of Pittsburgh. Previously, as Chief of Pediatrics, Dr. Singh’s leadership played a vital role in the Humber River Hospital Pediatric Program being named one of the top performing hospitals in Ontario for Pediatric Patient Experience. Dr. Singh is also the founder and driving force behind Guyana Help the Kids (GHTK), a charitable organization based in Toronto and dedicated to reducing infant mortality in Guyana.

    To view Dr. Narendra Singh's publications, visit PubMed

    About the Creator
    Dr. Narendra Singh