Yao Han-Yun, Liu Tsun-Jui, Lai Hui-Chin
Taipei Medical University, Wan Fang Hospital, Department of Anesthesiology, Taipei, Taiwan; Taichung Veterans General Hospital, Cardiovascular Center and Department of Medicine, Chiayi, Taiwan.
National Yang-Ming University, School of Medicine, Department of Medicine, Taipei, Taiwan; Taichung Veterans General Hospital, Cardiovascular Center and Department of Medicine, Chiayi, Taiwan.
Braz J Anesthesiol. 2019 Jul-Aug;69(4):390-395. doi: 10.1016/j.bjan.2019.03.012. Epub 2019 Aug 3.
Left double-lumen endotracheal tubes have been widely used in thoracic, esophageal, vascular, and mediastinal procedures to provide lung separation. Lacking clear objective guidelines, anesthesiologists usually select appropriately sized double-lumen endotracheal tubes based on their experience with 35 and 37 Fr double-lumen endotracheal tubes, which are the most commonly used. We hypothesized the patients with a left main bronchus of shorter length (<40 mm) had a greater chance of experiencing desaturation during one lung ventilation, due to obstruction in the orifice of the left upper lobe with the bronchial tube.
We included 360 patients with a left double-lumen intubated between September 2014 and August 2015. The patient's age, sex, height, weight, and underlying disease were recorded along with type of surgical procedure and the desaturation episodes. In addition, the width of the trachea and the width and length of the left bronchus were measured using computed tomography.
Patients with a left main bronchus length of less than 40 mm who underwent intubation with a left double-lumen endotracheal tubes had significantly higher incidence of desaturation (Odds Ratio (OR: 8.087)) during one-lung ventilation. Other related factors of patients identified to be at risk of developing hypoxia were diabetes mellitus (OR: 5.368), right side collapse surgery (OR: 4.933), and BMI (OR: 1.105).
We identified that patients with a left main bronchus length of less than 40 mm have a great chance of desaturation, especially if other desaturation risk factors are present.
左双腔气管导管已广泛应用于胸科、食管、血管和纵隔手术中，以实现肺隔离。由于缺乏明确的客观指南，麻醉医生通常根据他们使用最常用的35和37F双腔气管导管的经验来选择尺寸合适的双腔气管导管。我们推测，左主支气管较短（<40mm）的患者在单肺通气期间发生低氧血症的可能性更大，这是由于支气管导管阻塞了左上叶开口。
我们纳入了2014年9月至2015年8月期间接受左双腔插管的360例患者。记录患者的年龄、性别、身高、体重、基础疾病以及手术类型和低氧血症发作情况。此外，使用计算机断层扫描测量气管宽度以及左支气管的宽度和长度。
左主支气管长度小于40mm且接受左双腔气管导管插管的患者在单肺通气期间发生低氧血症的发生率显著更高（优势比（OR：8.087））。被确定有发生低氧血症风险的其他相关因素包括糖尿病（OR：5.368）、右侧塌陷手术（OR：4.933）和体重指数（OR：1.105）。
我们发现，左主支气管长度小于40mm的患者发生低氧血症的可能性很大，尤其是在存在其他低氧血症风险因素的情况下。
