Dexmedetomidine vs. Midazolam Sedation for Endobronchial Ultrasound

Benzodiazepines, opioids, and propofol are currently used alone or in combination for achieving sedation during endobronchial ultrasound and other bronchoscopic procedures. However, all these agents carry a risk of respiratory depression. Dexmedetomidine, a highly selective adrenergic alpha-2 agonist, has sedative and analgesic properties but does not cause respiratory depression. This study aims to compare efficacy and safety of dexmedetomidine as a sedative to midazolam in patients with hilar/mediastinal lymphadenopathy undergoing convex-probe endobronchial ultrasonography on day care basis. Patients will be randomized to receive either dexmedetomidine plus fentanyl or midazolam plus fentanyl prior to procedure, followed by dexmedetomidine or saline infusion respectively during the procedure. Ramsay sedation score of two will be targeted, failing which patients in both groups will receive midazolam bolus on as-needed basis. Bronchoscopist will remain blinded to group allocation. Patients will be monitored for sedation, oxygenation and hemodynamic parameters throughout. Need for additional midazolam, sedative efficacy, frequency of adverse respiratory and hemodynamic events, and bronchoscopist and patient satisfaction with the procedure will be compared between the two groups.

Inclusion criteria

• Age 18 years or more
• American Society of Anesthesiologists physical status I or II
• Presence of hilar and/or mediastinal lymph nodes on thoracic CT scan

Exclusion criteria

• Known allergy to dexmedetomidine or midazolam or fentanyl
• Documented coagulopathy
• Pregnancy
• Hemodynamic instability (hypotension, arrhythmia, recent acute coronary event)
• Neuropsychiatric illness
• History of previous endobronchial ultrasound procedure
• Refusal to provide consent