[Pediatric use of cuffed tracheal tubes under general anesthesia]

Although the use of cuffed tracheal tubes (CTT) in children less than 8 years of age has increased, the criteria for selecting CTTs of appropriate sizes have not been determined.

To study the criteria for choosing tubes of appropriate sizes (internal diameter: 4.0, 4.5, 5.0, or 5.5mm), we intubated 51 children aged 2-8 years under general anesthesia using an original protocol. We excluded 2 patients who received 4.0-mm tubes; thus, the outcomes in 48 patients were analyzed statistically.

A larger CTT was replaced with a smaller one in 1 patient, and a CTT was replaced with an uncuffed tracheal tube (UTT) in another patient (excluded from analysis). No tube changes were required in 49 patients. Post-extubation stridor was observed in 3 patients. The 4.5-mm tubes seemed appropriate in 12 cases because average airway leakage in these cases was > 10%; 5.0- and 5.5-mm tubes did not seem appropriate in 17 and 19 cases, respectively, because the leakage was < 10% of the tidal volume.

We recommend the pediatric use of CTTs because of the very low tube-exchange ratio and the acceptable incidence of stridor. However, the protocol may require modification.