Fiberoptic bronchoscopic positioning of double-lumen tubes

This article has attempted to familiarize the anesthesiologist with the bronchoscopic appearance of normally and abnormally positioned double-lumen endobronchial tubes. Double-lumen tubes are being used in an increasing proportion of thoracic surgical cases in major centers. Double-lumen tubes are also being used more frequently in intensive care units for independent lung ventilation, bronchopleural fistula, massive hemoptysis, and other asymmetrical pulmonary disorders. Obstruction of the left or right upper lobe bronchus is the most common significant malposition with these tubes. If it occurs after the start of surgery it can be extremely difficult to diagnose clinically and can lead to dangerous levels of hypoxemia during one-lung ventilation. The risk/benefit ratio of fiberoptic bronchoscopy before the initiation of one-lung ventilation is extremely small. Due to variations in bronchial anatomy and intrathoracic pathology there will always be a certain percentage of cases in which the current designs of double-lumen tubes cannot be adequately positioned. The anesthesiologist's index of suspicion in these cases may be raised by examining the preoperative chest x-ray. Fiberoptic bronchoscopy is the most efficient and reliable method to position a double-lumen tube when the anatomy is distorted. When used as described, the FOB is a monitor. Like all new monitors it will take some time before there is a general consensus whether it is to be used routinely or only for certain indications. Whatever the final consensus on the indications for the FOB in double-lumen tube positioning, it is certain that all anesthesiologists involved in managing thoracic cases should be familiar with this technique.