Statistical analysis
The sample size was calculated on the assumption that the incidence of coughing at the end of the anesthesia would be in two-thirds of patients (66%) and that lidocaine would decrease by 50% (to one third of the patients, 33%), thus 33 patients in each group for the primary outcome were needed for a power of 0.8 and alpha level of <0.05. We estimated a 10% drop-out rate. Data are presented as mean (SD) or median (range). The normality of distribution was tested with a D'Agostino-Pearson test. The significance of differences between the categorical variables was assessed with a Fisher exact test or chi square test, and that between continuous variables with a Mann-Whitney test a or 