Frerichs I, Schmitz G, Pulletz S, Schädler D, Zick G, Scholz J, Weiler N
Department of Anaesthesiology and Intensive Care Medicine, University Medical Centre Schleswig-Holstein, Campus Kiel, Schwanenweg 21, D-24105 Kiel, Germany.
Physiol Meas. 2007 Jul;28(7):S261-7. doi: 10.1088/0967-3334/28/7/S19. Epub 2007 Jun 26.
Electrical impedance tomography (EIT) has the potential to become a new tool for bedside monitoring of regional lung ventilation. The aim of our study was to assess the reproducibility of regional lung ventilation distribution determined by EIT during mechanical ventilation under identical ventilator settings. The experiments were performed on 10 anaesthetized supine pigs ventilated in a volume-controlled mode. EIT measurements were performed with the Goe-MF II device (Viasys Healthcare, Höchberg, Germany) during repeated changes in positive end-expiratory pressure (PEEP) from 0 to 10 cm H2O. Regional lung ventilation was determined in the right and left hemithorax as well as in 64 regions of interest evenly distributed over each chest side in the ventrodorsal direction. Ventilation distributions in both lungs were visualized as ventrodorsal ventilation profiles and shifts in ventilation distribution quantified in terms of centres of ventilation in relation to the chest diameter. The proportion of the right lung on total ventilation in the chest cross-section was 0.54+/-0.04 and remained unaffected by repetitive PEEP changes. Initial PEEP increase resulted in a redistribution of ventilation towards dorsal lung regions with a shift of the centre of ventilation from 45+/-3% to 49+/-3% of the chest diameter in the right and from 47+/-2% to 50+/-2% in the left hemithorax. Excellent reproducibility of the results in the individual regions of interest with almost identical patterns of ventilation distribution was found during repeated PEEP changes.
电阻抗断层成像（EIT）有潜力成为一种用于床边监测局部肺通气的新工具。我们研究的目的是评估在相同呼吸机设置下机械通气期间，由EIT测定的局部肺通气分布的可重复性。实验在10只麻醉状态下仰卧的猪身上进行，采用容量控制模式通气。使用Goe-MF II设备（德国霍赫贝格的Viasys Healthcare公司）在呼气末正压（PEEP）从0到10 cm H₂O反复变化期间进行EIT测量。在左右半胸以及沿腹背方向均匀分布在每侧胸部的64个感兴趣区域测定局部肺通气。两肺的通气分布以腹背通气剖面图呈现，通气分布的变化以通气中心相对于胸径的变化进行量化。右肺在胸部横断面总通气量中的比例为0.54±0.04，且不受PEEP反复变化的影响。初始PEEP增加导致通气重新分布至肺背侧区域，右半胸通气中心从胸径的45±3%移至49±3%，左半胸从47±2%移至50±2%。在PEEP反复变化期间，在各个感兴趣区域发现结果具有极好的可重复性，通气分布模式几乎相同。
