DexmedetomidineSafety Evaluation of Dexmedetomidine for EBUS-TBNA

Lung cancer is the second most commonly diagnosed primary neoplasia in Canada accounting for 22 865 new cases in 2007. Recent randomized trials have shown a significantly better diagnostic yield and fewer unnecessary thoracotomies with endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) when compared to conventional TBNA for various clinical conditions including peripheral pulmonary lesions and sarcoidosis. EBUS-TBNA are now routinely performed in our institution for staging of pulmonary and mediastinal cancer. EBUS-TBNA are performed under monitored anesthesia care (MAC) in the endoscopy suite at the Centre de soins ambulatoires of the Hôpital Maisonneuve-Rosemont.

Remifentanil, used in combined regime or as single agent proved to be effective and safe for MAC. Nonetheless, anesthesiologists are still confronted to the respiratory depression profile of remifentanil and other commonly used agents. An analysis of the ASA Closed Claims demonstrated that respiratory depression remains a significant drawback during MAC in remote locations. Furthermore, patients with coexisting pulmonary diseases scheduled for EBUS-TBNA are at increased risk of such complications.

The investigators hypothesize that compared to the use of remifentanil-based MAC protocol, the use of dexmedetomidine-based MAC protocol for EBUS-TBNA will result in a lower incidence of major respiratory and hemodynamic adverse events (bradypnea, apnea, oxygen desaturation, hypotension, hypertension, bradycardia and tachycardia) with equivalent overall procedure conditions.