Hemodynamic responses , including blood pressure and heart rate ( HR ) , were recorded at baseline ( T0 ) , before intubation ( T1 ) , during tracheal intubation ( T2 ) , 2 min after intubation ( T3 ) , upon eye opening on verbal commands ( T4 ) , during tracheal extubation ( T5 ) , and 2 min after extubation ( T6 ) .