Placement of a double lumen tube for lung surgery is best co

Placement of a double lumen tube for lung surgery is best confirmed by:
a) EtCo2
b) Airway pressure measurement
c) Clinically by auscultation
d) Bronchoscopy

D.
Tube position can be confirmed clinically by breath sounds heard on one side only but Fiberoptic bronchoscopy reveals the carina and the top edge of the blue bronchial cuff should be just visible in the intended main stem bronchus. When a right-sided tube is used, the fibrescope should be used to visualise the orifice of the right upper lobe bronchus.