BACKGROUND: There is no consensus on the best technique for lung isolation for thoracic surgery. In this study, we compared the clinical performance of three bronchial blockers (BBs) available in North America with left-sided double-lumen tubes (DLTs) for lung isolation in patients undergoing left-sided thoracic surgery.

METHODS: One hundred four patients undergoing left-sided thoracotomy or video-assisted thoracoscopic surgery were randomly assigned to one of the four lung isolation groups (n = 26/group). Lung isolation was with an Arndt(R) wire-guided BB (Cook(R) Critical Care, Bloomington, IN), a Cohen Flexi-tip(R) BB (Cook Critical Care) or a Fuji Uni-blocker(R) (Fuji Systems, Tokyo) or with a left-sided DLT (Mallinckrodt Medical, Cornamadde, Athlone, Westmeath, Ireland). Anesthetic management and lung isolation were performed according to a standardized protocol. Each group was randomly subdivided into two subgroups (n = 13/subgroup): immediate suction (at the time of insertion of the lung isolation device) (Subgroup I) or delayed suction (20 min after insertion of the lung separation device) (Subgroup D) according to when suction was applied to the BB suction channel or the bronchial lumen of the DLT. Using a verbal analog scale, lung collapse was assessed by the surgeons, who were blinded to the lung isolation technique.

RESULTS: There was no difference among the lung isolation devices in lung collapse scores at 0 (P = 0.66), 10 (P = 0.78), or 20 min (P = 0.51) after pleural opening. The time to initial lung isolation was less for DLTs (93 +/- 62 s) than BBs (203 +/- 132) (P = 0.0001). There were no differences among the BBs in the time to lung isolation (P = 0.78). There were significantly more repositions after initial placement of the lung isolation device with BBs (35 incidents) than with DLTs (two incidents) (P = 0.009). The Arndt BB required repositioning more frequently (16 incidents) than the Cohen BB (8) or the Fuji BB (11) (P = 0.032).

CONCLUSIONS: The three BBs provided equivalent surgical exposure to left-sided DLTs during left-sided open or video-assisted thoracoscopic surgery thoracic procedures. BBs required longer to position and required intraoperative repositioning more often. The Arndt BB needed to be repositioned more often than the other BBs.

AB BACKGROUND: Collapse of the ipsilateral lung facilitates surgical exposure during thoracic procedures. The use of different gas mixtures during two-lung ventilation (2LV) may improve or impede surgical conditions during subsequent one-lung ventilation (OLV) by increasing or delaying lung collapse. We investigated the effects of three different gas mixtures during 2LV on lung collapse and oxygenation during subsequent OLV: Air/Oxygen (fraction of inspired oxygen [Fio2] = 0.4), Nitrous Oxide/Oxygen (“N2O,” Fio2 = 0.4) and Oxygen (“O2,” Fio2 = 1.0). METHODS: Subjects were randomized into three groups: Air/Oxygen (n = 33), N2O (n = 34) or O2 (n = 33) and received the designated gas mixture during induction and until the start of OLV. Subjects’ lungs in all groups were then ventilated with Fio2 = 1.0 during OLV. The surgeons, who were blinded to the randomization, evaluated the lung deflation using a verbal rating scale at 10 and 20 min after the start of OLV. Serial arterial blood gases were performed before anesthesia induction, during 2LV, and every 5 min, for 30 min, after initiation of OLV. RESULTS: The use of air in the inspired gas mixture during 2LV led to delayed lung deflation during OLV, whereas N2O improved lung collapse. Arterial oxygenation was significantly improved in the O2 group only for the first 10 min of OLV, after which there were no differences in mean Pao2 values among groups. CONCLUSIONS: De-nitrogenation of the lung during 2LV is a useful strategy to improve surgical conditions during OLV. The use of Fio2 1.0 or N2O/O2 (Fio2 0.4) during 2LV did not have an adverse effect on subsequent oxygenation during OLV. (C) 2009 by International Anesthesia Research Society.