Ease of insertion of the laryngeal tube during manual-in-line neck stabilisation.

The laryngeal tube has a potential role in airway management during anaesthesia or cardiopulmonary resuscitation. In patients with unstable necks, the head and neck may need to be stabilised manually (manual in-line stabilisation), but it is not known whether this procedure affects the ease of insertion of the laryngeal tube. We studied, in a cross-over study, 21 adult patients to compare the success rate of ventilation through the laryngeal tube between the Magill position (a pillow under the occiput and the head extended) or the manual in-line position of the head and neck (without a pillow under the occiput). After induction of anaesthesia and neuromuscular blockade, the laryngeal tube was inserted in turn in the two positions. The ease of insertion was scored with four categories (easy, moderately difficult, difficult and impossible), and adequacy of ventilation through the device was assessed. Ventilation was adequate in all 21 patients in the Magill position, but only in two of 21 patients during manual in-line positioning (p < 0.01; 95%CI for difference: 68-94%). In the Magill position, insertion of the laryngeal tube was easy in 16 patients and moderately difficult in the remaining five patients; in the manual in-line stabilisation position, insertion was moderately difficult in two patients and impossible in the remaining 19 patients. Stabilisation of the patient's head and neck by the manual in-line method made insertion of the laryngeal tube either difficult or impossible.