Forrest F C, Randalls P B, Barnas G M, Hoff B H, Oletsky J, Mackenzie C F
Department of Anesthesiology, University of Maryland, Baltimore 21201.
Respir Physiol. 1994 Feb;95(2):147-54. doi: 10.1016/0034-5687(94)90112-0.
We used a technique of measuring Xenon133 washout (XeW) from the alveolar space to evaluate transfer of gas from the acinus (Mackenzie et al., J. Appl. Physiol. 68: 2013-2018, 1990) during 2 min of apnea, 2 min of tracheal insufflation with oxygen (TRIO) and 90 sec of intermittent positive pressure ventilation (IPPV) in 6 anesthetized and paralyzed dogs. Xenon133 dissolved in saline was injected into an occluded acinar region through a pulmonary artery catheter, and XeW was measured by gamma scintillation scanning. With this technique, XeW during apnea represents the contribution of cardiogenic oscillations in regional flow. The XeW rate constant (min-1 +/- SE) was 0.37 +/- 0.03 during apnea. This was not different (P > 0.05) with TRIO (0.29 +/- 0.04). With IPPV, the rate constant increased to 3.49 +/- 0.39, faster than with either apnea or TRIO (P < 0.001). We conclude that: (1) TRIO does not increase convective gas transfer from the acini compared to apnea; and (2) transfer of gas out of the acini due to cardiogenic oscillations is a very small portion of the total gas eliminated during IPPV.
我们采用一种测量肺泡腔中氙-133清除率（XeW）的技术，以评估6只麻醉并麻痹的犬在2分钟呼吸暂停、2分钟经气管给氧（TRIO）以及90秒间歇性正压通气（IPPV）过程中气体从腺泡的转运情况（Mackenzie等人，《应用生理学杂志》68: 2013 - 2018, 1990）。将溶解于生理盐水中的氙-133通过肺动脉导管注入阻塞的腺泡区域，并用γ闪烁扫描测量XeW。采用该技术，呼吸暂停期间的XeW代表了区域血流中心源性振荡的作用。呼吸暂停期间XeW的速率常数（分钟⁻¹±标准误）为0.37±0.03。TRIO期间该值（0.29±0.04）与之无差异（P>0.05）。在IPPV时，速率常数增至3.49±0.39，比呼吸暂停或TRIO时都快（P<0.001）。我们得出结论：（1）与呼吸暂停相比，TRIO不会增加腺泡的对流性气体转运；（2）在IPPV期间，由心源性振荡导致的腺泡气体排出量占总气体清除量的比例非常小。
