Paediatric gastric tubes

A child with status epilepticus has been stabilised and intubated and is awaiting admission to the paediatric intensive care unit. You decide to insert a nasogastric tube. The nurse asks the following questions:

1. What size gastric tube would you like?

A general guide is twice the size of the uncuffed tracheal tube.
A four year old for example would usually need a tracheal tube size of 5.0mm internal diameter (age/4 +4), so would need a 10 Fr gastric tube.

2. To what length are you intending to insert it?

A formula based on height of the child can be used, so get your tape measure or length chart out:

NGTpaed

For neonates < 2 weeks and children >8 years 4 months a method called NEMU (nose-ear-midxiphoid-umbilicus measurement) may be used.

3. How will you confirm placement?

It is very likely this child will get a post-intubation chest radiograph and the gastric tube tip can be visualised on that. However non-radiological tests should be used and pH testing of the aspirate is recommended, looking for pH<6

Further details on these measurements including positive and negative likelihood ratios of pH testing can be found in the evidence-based guideline from Cincinnati Children’s Hospital