Effect of intracuff alkalinized 2% lidocaine on endotracheal tube cuff pressure and postoperative throat symptoms in anaesthesia maintained by nitrous oxide.

Aim To compare the effects of endotracheal tube cuff inflation media, air, saline and alkalinized 2% lidocaine on increase of cuff pressure (CP) during nitrous oxide maintained anaesthesia and on incidence of postoperative throat symptoms (PTS), and to evaluate the incidence of postoperative throat mucosal injuries (PTMI) depending on cuff inflation medium. Methods Ninety patients who had undergone elective surgery were randomly allocated into 3 equal groups per cuff inflation media: air (group A), saline (group S) and alkalinized 2% lidocaine (group L). The CP was monitored immediately after cuff inflation and further 5, 15, 30, 60 and 90 minutes after intubation. The incidence and intensity of PTS, sore throat, hoarseness, dysphagia and cough were evaluated 2, 6 and 24 hours after extubation. The incidence and intensity of PTMI were evaluated 24 hours after exubation using indirect laryngoscopy examination. Results The highest increase of mean CP was recorded in the group A (18.7±4.9), it was significantly lower (6.4±1.1) in the group S, while it remained stable in the group L (0.7±0.7). All PTS occurred less frequently in the group L: sore throat (p<0.001), hoarseness and dysphagia (p<0.05), but the incidence of cough was not significantly different between the groups. The lowest incidence of PTMI was in the group L (p< 0.001). Conclusion The increase of CP contributed to incidence of PTS. The intracuff alkalinized 2% lidocaine was superior to saline and air in the prevention of an increase of CP and reduction of the PTS incidence. There was a strong correlation between the incidence of PTS and PTMI.