Dextromethorphan premedication reduces midazolam requirement: Objective and subjective parameters in peribronchoscopy

Background: Coughing is increased during bronchoscopy and may last for several hours after the procedure. Also prior to the procedure patients show high levels of anxiety due to fear of the pain and breathing difficulties that they might experience during the procedure. Objectives: To evaluate the antitussive, anxiolytic and sedative effect of dextromethorphan (DM) premedication on the amount of intravenous midazolam during bronchoscopic procedures. Methods: Sixty consecutive patients undergoing scheduled bronchoscopy were randomly allocated in a double-blind, placebo-controlled study. Half received 90 mg DM and half placebo. Local anesthesia with 2 ml of repeated intratracheal instillation of 1% lidocaine as needed during bronchoscopy was applied. Midazolam 1 mg (maximum of 5 mg) was administered intravenously until a satisfactory sedation was achieved. Results: Heart rate, systolic and diastolic pressure and SpO₂ were assessed before and during bronchoscopy. A visual analog score (VAS) for pain, cough, communication, cooperation, emotional state, complaints, expectoration, level of information about the procedure, feeling of unpleasantness and stress level assessed before and after the examination by the patient and the physician was used. There were no significant differences in the reported degrees of difficulty in undergoing bronchoscopic procedures. DM patients needed significantly fewer lidocaine instillations and lower midazolam dosage, achieved better analgesia, had lower emotion and complaint scores, significantly less coughing, significantly less stress, were significantly more cooperative, found that the procedure was much less unpleasant than they had expected, and produced less sputum at end of the procedure. Conclusions: DM is an effective bronchoscopic premedication in combination with midazolam and improves the overall well-being of the patients.