Ty-jour t1 - 慢性气道阻塞患者的平均肺泡气体估计JF - 欧洲呼吸杂志Jo - Eur Respir J SP - 451 LP - 460 VL - 2是 - 5 Au - Giannella-Neto，AU - Paoletti，PAu - Fornai，E Au - Giuntini，C Y1 - 1989/05/01 UR - //www.qdcxjkg.com/content/2/5/451.Abstract n2 - 肺泡到动脉差异（AAD）可以计算出来来自代表性的肺泡气体压力（PA）。这些在慢性气道阻塞（CAO）和通气/灌注（Va / Q）比率的严重不均匀性的患者中特别难以获得。在25例患者中，使用计算机化质谱仪，获得肺泡气体的代表值：1。作为末端潮浓度（ET）;2.使用肺泡空气方程与Paco2导出的Paco2（是）;3.将PACO2 = PACO2放入肺泡空气方程中以计算理想的O2肺泡压力（ID）;4.施加Rahn对“平均”肺泡气体（Rd）的定义，即在每个第三呼吸内，对应于瞬时气体交换比R（t）j等于该呼吸Rj的总交换比的牙槽压。在安静呼吸期间，R（T）J等于RJ的点以71％的潮气量（vt）发生。由Be和Rd的肺泡压力产生类似的值（115.5 +/- 6.9和115.5 +/- 6.6mmHg，分别用于CO2的O2和30.3 +/- 5.7和30.8 +/- 5.7mmHg），但它们显着不同 those by ET and ID (106.2 +/- 9.5 and 95.6 +/- 13.5 mmHg for O2 and 36.3 +/- 7.7 and 48.2 +/- 11.2 mmHg for CO2, respectively). These findings may be explained considering that PA(BE) and PA(RD) represent both high and low VA/Q units, whereas PA(ET) and PA(ID) represent mainly low VA/Q units. AaDCO2 by RD and BE appeared proportional to the severity of CAO as estimated from VT. Automated techniques make it possible to substitute end-tidal determinations with more accurate estimates either by measuring anatomical dead-space and using Bohr's equation or by applying Rahn's definition. ER -