[Tracheal tube obstruction caused by local anesthetic gel].

A case report of tracheal tube obstruction caused by a thin, almost invisible, membrane is presented. It was found probable that the membrane consisted of dried local anaesthetic gel. An experimental study showed that inadvertent application of 0.3 ml of lignocaine or prilocaine gel at the orifice of the tube may result in the formation of such a membrane. After 48 hours, the membrane resisted any pressure that might be generated in a resuscitation bag.