For each procedure, the staff consists of a chest physician trained in FB (operator), a physician in charge of sedation and two nurses for technical assistance and proper data recording. Before the procedure, blood pressure (BP), heart rate (HR), oxygen saturation (SaO2) and weight are recorded. The patient is placed in supine position, fitted with a nasal oxygen cannula and a peripheral intravenous access (18-20 G) for the infusion of crystalloids. Oxygen is administered only if SaO2 was < 92%. Local anaesthesia is done using lidocaïne 10 % and 1% in the pharynx and central airways respectively. The sedative drugs syringes and lines are hidden from the operator by a sheet. Sedation is then started with P or M according to randomization for any FB as follows: We inject in both groups a 5 ml bolus of lidocaine 1% (50 mg) (prevention of pain associated with P injection), followed by either a 40 mg (4 ml) bolus of P or 2 mg of M. The re-injection of 20 mg (2ml) of P or 2 mg of M was allowed every 2 minutes to achieve and maintain BIS values between 70 and 85 and OAA/S of 3-4. Blood pressure, oxygen saturation, heart rate, BIS and OAA/S are monitored continuously and recorded every 3 minutes during the procedure and at 5, 15, 30, 45 and 60 minutes after its end. We record the time necessary to achieve the targeted BIS value after the injection of the sedative drug, the duration of FB, the electroencephalographic recovery time, defined as the time to reach a BIS value > 90 after the end of FB and total doses of M and P.