Devices for Lung Isolation Used by Anesthesiologists with Limited Thoracic Experience

Abstract

Background Lung isolation is accomplished with a double-lumen tube or a bronchial blocker. Previous studies comparing lung isolation methods were performed by experienced anesthesiologists in thoracic anesthesia. Therefore, the results of these studies may not be relevant to the anesthesiologist with limited experience. This study compared the success rates of lung isolation devices among anesthesiologists with limited experience in thoracic anesthesia. Methods A prospective, randomized trial was designed to determine the success and time required for proper placement of the left-sided double-lumen tube (n = 22), the Univent tube (Vitaid Ltd., Lewiston, NY; n = 22), and the Arndt Blocker (Cook Critical Care, Bloomington, IN; n = 22). Anesthesiologists with less than two lung isolation cases per month were included (faculty n = 17 and senior residents n = 11). Variables recorded included (1) successful placement (as determined by an independent observer), (2) time of placement, and (3) the number of times the fiberoptic bronchoscope was used. Results Participants failed to place or position their assigned device in 25 of 66 patients (failure was 39% among faculty and 36% among senior residents). The failure rate did not differ among the three devices (P = 0.65). The median (25th-75th percentile) times to complete the placement procedures were as follows: (1) double-lumen tube: 6.1 min (4.6-9.5 min), (2) Univent tube: 6.7 min (4.9-8.8 min), and (3) Arndt Blocker: 8.6 min (5.8-17.5 min) (P = 0.45 comparing all devices). After device malposition was identified, it took 1 min or less for the investigating anesthesiologist to achieve optimal position. Conclusions Anesthesiologists with limited experience in thoracic anesthesia frequently fail to successfully place lung isolation devices. Rapid successful device placement by an experienced anesthesiologist excluded any contribution of uniquely difficult anatomy. The nature of the malpositions suggests that the most critical factor in successful placement was the anesthesiologist's knowledge of endoscopic bronchial anatomy.