Lung isolation in the morbidly obese patient: a comparison of a left-sided double-lumen tracheal tube with the Arndt wire-guided blocker

Obese patients are at risk of complications during airway management including difficult tracheal intubation. There are no reports regarding the ease of intubation or efficiency of lung collapse with the use of lung isolation devices for the morbidly obese patient. We conducted a prospective, randomized study in morbidly obese patients undergoing one-lung ventilation. We compared the effectiveness and ease of placement of a left-sided double-lumen tube and the Arndt blocker. Fifty adult patients undergoing thoracic surgery were randomly assigned to a double-lumen tracheal tube (DLT) or standard single-lumen tracheal tube and an Arndt blocker. The primary endpoint was to record the number of times the tube/devices were successfully positioned at the first attempt and the time spent to achieve optimal position as verified by fibreoptic bronchoscopy. A secondary outcome was the adequacy of lung collapse. For the left-sided DLT group, there were three intubation failures on the first attempt. This group required an alternative method with an airway exchange catheter technique to advance the DLT. In the single-lumen tracheal tube with an Arndt blocker group, there were two intubation failures on the first attempt. After lung isolation devices were placed, lung collapse was clinically comparable in both groups. There is no overall advantage of one device over the other during intubation of the morbidly obese patient.