Minh V D, Chun D, Dolan G F, Lee H M, Vasquez P
Am Rev Respir Dis. 1981 Sep;124(3):226-31. doi: 10.1164/arrd.1981.124.3.226.
Mixed venous oxygenation (partial pressure, PVO2; saturation, SVO2) and its impact on pulmonary function at rest in the supine position (SUP), at rest in the standing position (STAND), and during maximal treadmill exercise (Emax), were studied in 41 stable patients with chronic obstructive pulmonary disease, using arterial and right heart (Swan-Ganz) catheterization. The patients represented a broad spectrum of disease severity (VC, 3.1 +/- 0.9 L; FEF 25-75, 1.0 +/- 0.7 L). It was found that: (a) venous oxygenation was uniform among different patients in the supine position at rest (PVO2, 33.8 +/- 2.4 mmHg' SVO2, 76.2 +/- 3.6%), regardless of the heterogeneity in airway obstruction, as previously reported by others; (b) venous oxygenation was also uniform in STAND (PVO2, 29.5 +/- 2.5 mmHg; SVO2, 58 +/- 3.9%) and treadmill Emax (PVO2, 22.4 +/- 3.3 mmHg; SVO2, 34.4 +/- 6%), an observation not previously reported; (c) the orthostatic mixed venous desaturation at rest was pronounced, and was nearly as great as that from STAND to Emax; (d) the potential effect of mixed venous desaturation on alveolar O2 partial pressure (PAO2) and end-capillary O2 saturation (SCO2) was not obvious from SUP to STAND, and from STAND to Emax conditions, being masked by an appropriate increase in overall V/Q ratio; (e) because of constant SCO2 and low interindividual variations of SVO2, there was a high correlation of arterial saturation (SaO2) to venous admixture (Qva/Qt, sum of true shunt and shuntlike components) for each of the conditions studied. Hence, because of high correlation of the equations relating SaO2 to Qva/Qt (r greater than 0.9), these relationships might be used for noninvasive prediction of Qva/Qt from SaO2 in patients with COPD.
采用动脉导管和右心（Swan-Ganz）导管插入术，对41例稳定期慢性阻塞性肺疾病患者在仰卧位静息状态（SUP）、站立位静息状态（STAND）以及最大运动平板试验（Emax）期间的混合静脉氧合（分压，PVO2；饱和度，SVO2）及其对肺功能的影响进行了研究。这些患者代表了广泛的疾病严重程度范围（肺活量，3.1±0.9升；用力呼气流量25%-75%，1.0±0.7升）。研究发现：（a）如其他人先前报道的那样，尽管气道阻塞存在异质性，但在仰卧位静息状态下，不同患者的静脉氧合是均匀的（PVO2，33.8±2.4 mmHg；SVO2，76.2±3.6%）；（b）在站立位（PVO2，29.5±2.5 mmHg；SVO2，58±3.9%）和平板运动Emax期间（PVO2，22.4±3.3 mmHg；SVO2，34.4±6%）静脉氧合也是均匀的，这一观察结果此前未见报道；（c）静息时直立位混合静脉血氧饱和度明显下降，且几乎与从站立位到运动Emax时的下降幅度一样大；（d）从仰卧位到站立位以及从站立位到运动Emax状态下，混合静脉血氧饱和度对肺泡氧分压（PAO2）和毛细血管末端氧饱和度（SCO2）的潜在影响不明显，被整体通气/血流比值的适当增加所掩盖；（e）由于SCO2恒定且SVO2的个体间差异较小，在所研究的每种状态下，动脉血氧饱和度（SaO2）与静脉血掺杂（Qva/Qt，真性分流与类分流成分之和）高度相关。因此，由于将SaO2与Qva/Qt相关联的方程具有高度相关性（r大于0.9），这些关系可用于无创预测慢性阻塞性肺疾病患者的Qva/Qt。
