Propofol is ideal for bronchoscopy sedation because of its fast onset and quick recovery effect. Our research and reports from different investigators demonstrate that patients received propofol sedation recover fast with excellent satisfaction for bronchoscopy. However, the amount of propofol for induction and maintenance is calculated simply by patient's body weight and physicians' experience. For those non-anesthesiologists, who perform sedative work outside the operating room, and inexperienced anesthesiologist without fully considering the individual pharmacokinetic and pharmacodynamic differences may generate unstable drug plasma concentration and increase cardio-respiration suppression. Therefore, a manner which can assess and measure objectively individual pharmacokinetic differences may improve the sedative quality and decrease the complication rate.