Choosing the right tracheal tube: should we use a body length based system?


We read with great interest the editorial by Farrow et al. [1]. We agree with the authors’ assertion for the placement of smaller tracheal tubes for routine anaesthesia and that choice of tube size should deserve greater consideration.

Tracheal diameter can be accurately estimated from body length in both paediatric and adult populations [2]. Length-based systems have been shown to be superior to age-based formulae in paediatric populations [3, 4], though no system is widely used amongst adults. Application of a body length-based system would allow greater individualisation of tube size and provide an alternative to the largely arbitrary age- or sex-based methods widely used.