One lung ventilation & lung isolation

Indication

The adult trachea is 10–12 cm long and bifurcates at the carina into the left (LMB) and right (RMB) main bronch

Anteriorly, the trachea is supported by cartilaginous semicircular rings and posteriorly by the trachealis muscle

The LMB is narrower and longer than the RMB.

The average length of the LMB is 5.3 cm compared with 2.7 cm for the RMB

	Advantages	Disadvantages
Double lumen tube	- Quicker to place - Can alternate ventilation to either lung - Fibreoptic bronchoscope not essential	- Limited sizes available - Difficult to place correctly when anatomy is distorted or abnormal - Not ideal if postoperative ventilation needed - Higher risk of causing airway trauma
Bronchial blocker	- Easy size selection - Can be used with a standard tracheal tube, useful in patients already intubated or with tracheostomy - Used with a single-lumen tube which is easier to insert in cases of difficult intubation - Selective lobar isolation possible - Can be easily withdrawn if postoperative ventilation required	- Takes longer to insert - FOB essential - Suction of isolated lung not as effective - Bronchoscopy of isolated lung not easy - Difficult to alternate side of OLV (e.g. for thoracic sympathectomy) (possible with a Rusch EZ-Bifid blocker) - More prone to displacement intraoperatively