Ventilator-assisted nasotracheal intubation.

Abstract

We read with interest the letter on nsotracheal intubation (Zych & Crossley. Anaesthesia 2003; 58: 919) which highlighted the prolonged apnoea and associated desaturation that can limit the time available for blind nasal intubation in the paralysed patient. Tracheal cuff inflation has been used as an aid to blind nasal intubation and was first described by Gorbach [1]. Van Elstraete et al. found inflating the tube cuff in the oropharynx increased the success rate of blind nasal intubation in the paralysed, apnoeic patient [2]. We employ a method of blind nasal intubation based on a cuff inflation technique, which enables us to continuously ventilate the patient during the procedure. The patient's head is positioned on a pillow with some extension of the atlanto-occipital joint. A softened, warmed, nasal pre-formed tracheal tube is passed through the nostril into the oropharynx, and the cuff inflated with 15 ml of air. The tube is connected via a breathing system to a ventilator. The mouth and the opposite nostril are occluded and adequate ventilation confirmed by capnography and visible chest wall movement. At this stage the lungs can usually be ventilated easily and, if necessary, ventilation can be improved by drawing back slightly on the tube. The tube is then gently advanced until resistance is felt and tenting in the neck is seen at the level of the thyroid cartilage. The carbon dioxide waveform should still be visible. The cuff is deflated and the tube then advanced into the trachea. If ventilation or the carbon dioxide waveform are deemed to be inadequate the tube is withdrawn slowly until ventilation has improved. The tube can then be advanced again with rotation or with a change in the degree of atlanto-axial extension [3]. We find this method advantageous as it allows maintenance of oxygenation, and is a safe and unhurried approach to blind nasal intubation. The ability to ventilate a patient may also be useful in patients after a failed nasotracheal intubation.