[The Mallampati's scale: a study of reliability in clinical practice]

The need to predict the rank of difficulty of tracheal intubation is of paramount importance in anaesthesia as has been well documented in numerous studies. We assessed the use of the Mallampati scale as possible predictive indicator of difficult tracheal intubation in a study conducted on 700 patients. The rank of difficulty determined during the pre-anaesthesiological examination by the Mallampati scale, was compared to the Cormack scale as assessed by the laryngeal direct examination at the beginning of anaesthesia. The correlation between the two first ranks of both scales was highly significant. The evaluation by the scale of Mallampati showed a good sensibility and a low specificity with incorrect overestimation only for the difficult intubation. In our study orotracheal intubation was rated difficult in 10.4% of the patients by the Mallampati scale and in 11% of the patients score by the Cormack scale. The chin to jugulum distance, also studied as a possible predictive parameter, did not correlate with the Cormack scale.