Anesthesia of the tracheobronchial (TB) pathways during laser therapy (LT) faces a variety of problems including analgesia and sedation in patients with respiratory difficulties or who continue to breathe spontaneously while the airways are occupied by operating instruments. During the course of the study, two methods of anesthesia were compared in 36 patients undergoing LT of the TB pathways. The first method (Group A, n = 16) involved the use of Diazepam as an hypnotic starter and Fentanyl as an opioid analgesic in continuous infusion. Propofol was used both as an inducer and as the main drug in the second method (Group B, n = 20) in order to reduce the opioid dose required. The following variables were studied: heart rate, systolic and diastolic blood pressure, blood gas analytic parameters, side-effects such as cough and intraoperative movement, and disturbances of heart rhythm and conduction; in addition, the duration of operations and the time taken to regain consciousness were recorded, together with the total dose of Fentanyl used. An improved hematosis was observed in patients treated with Propofol during the operation and on regaining consciousness, and the time taken to regain consciousness was significantly reduced. No significant differences were observed between the two groups with regard to cardiocirculatory variables or undesirable effects.