Laryngeal mask airway insertion using cricoid pressure and manual in-line neck stabilisation.

Forty patients were studied to assess the ease of insertion of the laryngeal mask in the simultaneous presence of cricoid pressure and manual in-line stabilisation of the neck. This was compared with the normal technique of laryngeal mask insertion in the same patients. Fibreoptic views obtained through the laryngeal mask were documented on each occasion. The device was inserted successfully in all 40 patients when the head was kept in the normal position. This was achieved on the first attempt in 33 patients. When cricoid pressure and manual in-line neck stabilisation were applied, successful laryngeal mask insertion was only possible in 29 patients, with correct placement at the first attempt in 14 patients. The differences were statistically significant (p < 0.001). When cricoid pressure and neck stabilisation were applied, vocal cord visualisation through the laryngeal mask with a fibreoptic bronchoscope was only possible in 15 patients. With the head in the normal position the vocal cords were seen in 33 patients. The implications of these results are discussed with respect to the role of the laryngeal mask in the multiply injured patient.