Paediatric “tube” sizes

You decided to intubate a child and wisely remembered that you should also follow with an NG/ OG after intubation to decompress the stomach.  In order to avoid the blank stare when asked “what size”?  Here’s a nice mnemonic about Pediatric “tube” sizes… easy as 1-2-3-4!!!  Please note ETT = endotracheal tube size.

  • 1 x ETT = (age/4) + 4 (formula for uncuffed tubes)
  • 2 x ETT = NG/ OG/ foley size
  • 3 x ETT = depth of ETT insertion
  • 4 x ETT = chest tube size (max, e.g. hemothorax)

So for example, a 4-year-old child would get intubated with a 5-0 ETT inserted to depth of 15 cm (3x ETT), a 10Fr NG/OG/foley (2x ETT), and a 20Fr chest tube (4x ETT).

Also, remember that you can use cuffed tubes in any child except neonates but the formula needs to be adjusted as follows: cuffed endotracheal tube ID (mm) = (age/4) + 3.5

When intubation fails…


We should never allow more than 3 intubation attempts, and sometimes clinical conditions will dictate fewer tries. Examples that come to mind are severe brain injury patients (hypoxia is bad) and patients who do not recover from oxygen desaturation when they are bagged. Don’t lose track of time and the number of attempts!


How to Master Tracheal Intubation

How do I shape the stylet

  1. Preparation
    a. Select the right blade size.
    b. Shape the stylet and ETT straight to the cuff, then bend at a 30-35 degree angle.
    c. Properly position the patient Ear-to-Sternal-Notch with face plane parallel to ceiling.
  2. Epiglottoscopy
    a. Progressively and methodically advance the tip of the blade midline and gently seat in the vallecula.
  3. Laryngeal Exposure
    a. If the view is still not optimal, consider trying ELM, or HELP to improve visualization.
  4. Tube Delivery
    a. Using straight-to-cuff shaping, insert near the right corner of the mouth and advance upward.
    b. Pass the tip anterior to the interarytenoid notch.
    c. Ensure the cuff of the tracheal tube is below the level of the cords.
  5. Tube Confirmation and Maintenance
    a. Direct visualization
    b. Absent sounds over the epigastrium
    c. Equal bilateral breath sounds
    d. Good compliance with the BVM
    e. Tube fogging (never primary)
    f. Continuous waveform capnography (for confirmation and maintenance)
    g. Rising SpO2 (for patients with a pulse)

Apneic Preoxygenation

Use of ApOx during RSI in adult patients in the ED, is low cost, low complexity, and not proven to cause harm while also reducing incidence of hypoxemia and increasing first pass attempt intubation. It is time for a RCT evaluating this modality.

Apneic preoxygenation

Apneic oxygenation without nasal prongs – the “Hungarian Air Ambulance method”. a The intubator preoxygenates the patient with a non-rebreathing mask (15 lpm). Upper airway patency is maximized by two naso- and one oropharyngeal airway. b The intubator cuts the tubing of the mask after the onset of apnea. c The intubator removes the mask and inserts the free end of the tubing approximately 3–5 cm deep into the nasopharyngeal airway. d The laryngoscopy is performed with the “tube in the tube”