Warming the tracheal tube and kinking.

To the Editor: We read with interest the letter on intratracheal kinking of an endotracheal tube by Lee et al.1 The authors highlighted that, in addition to various known causes of obstruction of the endotracheal tube, intratracheal kinking at the site where the inflating lumen opens into the cuff can also cause its obstruction. Their observation is similar to that of Singh et al.2 where the authors could barely pass the endotracheal tube through the nasal cavity following soaking it in warm water. It is well known that thermal softening of the polyvinyl chloride tracheal tube can lead to its distortion and obstruction.3 In the case reported by Lee et al., we postulate that warming the tube to soften it contributed to kinking at the tube’s weakest point, i.e., the site where the inflating lumen opens into the cuff. We feel that the practice of softening the endotracheal tube should be avoided. If one is unable to intubate with a particular size tube it is better to use a smaller size that can be inserted without causing trauma.