Reber A, Engberg G, Sporre B, Kviele L, Rothen H U, Wegenius G, Nylund U, Hedenstierna G
Department of Anaesthesiology and Intensive Care, University Hospital, Uppsala, Sweden.
Br J Anaesth. 1996 Jun;76(6):760-6. doi: 10.1093/bja/76.6.760.
Spiral computed tomography (CT) allows volumetric analysis of formation of atelectasis and aeration of the lungs during anaesthesia. We studied 26 premedicated patients undergoing elective surgery allocated to group 1 (conscious, spontaneous breathing, investigating inspiration and expiration), group 2 (general anaesthesia with mechanical ventilation, investigating inspiration and expiration) or group 3 (general anaesthesia with mechanical ventilation, investigating changes over time). Using spiral CT, the lungs were studied either before or during general anaesthesia. CT scans were grouped into the following areas: overaeration, normal aeration, reduced aeration, poor aeration and atelectasis. The mechanism of atelectasis appeared to be both gravitational forces and a diaphragm-related force that acts regionally in caudal lung regions. Mean atelectasis formation and poorly aerated regions comprised approximately 4% of the total lung volume between the diaphragm and carina, giving a mean value of 16-20% of the normal aerated lung tissue being either collapsed or poorly aerated. The vertical ventilation distribution was more even during anaesthesia than in the awake state.
螺旋计算机断层扫描（CT）可对麻醉期间肺不张的形成及肺通气情况进行容积分析。我们研究了26例接受择期手术的术前用药患者，将其分为1组（清醒、自主呼吸，研究吸气和呼气）、2组（全身麻醉并机械通气，研究吸气和呼气）或3组（全身麻醉并机械通气，研究随时间的变化）。使用螺旋CT在全身麻醉前或麻醉期间对肺部进行研究。CT扫描被分为以下区域：过度通气、正常通气、通气减少、通气不良和肺不张。肺不张的机制似乎既有重力作用，也有与膈肌相关的力，该力在肺下部区域局部起作用。在膈肌与隆突之间，平均肺不张形成区域和通气不良区域约占肺总体积的4%，这意味着正常通气肺组织中平均有16% - 20%的组织出现萎陷或通气不良。与清醒状态相比，麻醉期间垂直通气分布更均匀。
