Assessment of Quality and Time of Lung Isolation with Univent Blocker

Objectives: One-lung ventilation (OLV) is used during thoracic surgery to protect the healthy lung from contamination while providing optimal surgical exposure. This study evaluated successful lung isolation and the time to lung collapse using the Univent blocker in patients undergoing thoracoscopic surgery.
Methods: Patients requiring lung isolation between November 2014 and February 2016 were prospectively enrolled. Demographic data, ASA physical status, Mallampati and Cormack–Lehane scores, and the need for airway adjuncts were recorded. Placement time was defined as the interval between laryngoscopy and bronchoscopic confirmation of blocker position. Lung collapse was assessed by the surgeon at 5, 10, 15, and 20 minutes after blocker inflation. Airway pressures (peak, plateau, and PEEP), dynamic compliance, inspired oxygen fraction (FiO₂), and end-tidal carbon dioxide (EtCO₂) were monitored throughout surgery.
Results: Twenty-eight patients completed the study. The right lung was isolated in 17 (61%) patients and the left lung in 11 (39%). At 5 minutes, lung collapse was graded as poor in 11%, fair in 64%, and excellent in 25% of patients; at 20 minutes, 50% were graded as fair and 50% as excellent. Blocker placement times were similar between right- and left-sided isolation (134±107 s vs. 117±77 s). However, the time to lung collapse was significantly longer for right-sided isolation (222±148 s vs. 142±56 s, p<0.05). Respiratory mechanics were comparable between groups.
Conclusion: The Univent blocker provides effective lung isolation. Although adequate lung collapse requires a certain amount of time, respi-ratory mechanics remain preserved during OLV.

Keywords: Bronchial blocker, one-lung ventilation, video-assisted thoracic surgery