Department of Occupational Lung Diseases and Tuberculosis, Sismanogleio-Amalia Fleming General Hospital, Athens, Greece.
Department of Medical Laboratories, Faculty of Health and Caring Professions, University of Applied Sciences / Technological Educational Institute (TEI) of Athens, Athens, Greece.
Postgrad Med J. 2018 Feb;94(1108):81-86. doi: 10.1136/postgradmedj-2017-135164. Epub 2017 Sep 28.
Inconsistent and contradictory findings have appeared in the literature concerning the impact of body position on oxygenation in pleural effusion.
We attempted to elucidate whether the size of the pleural effusion in patients with no parenchymal disease is the main determinant of posture-induced alterations in oxygenation parameters. We studied 62 spontaneously breathing patients aged 65.3±7.8 years (mean±SD), of whom 36 had large and massive-sized effusions (Group A) and 26 had small and moderate-sized effusions (Group B). Arterial blood gases were determined in four different body positions: sitting (SIT), supine (SUP), ipsilateral (IPS) and contralateral (CON) to the effusion side, after remaining relaxed for at least 20 min in each position. Separation into groups A and B was deliberately set from the position of the fluid meniscus line on a posteroanterior chest film just above the upper costal margin of the sixth anterior rib. A two-way ANOVA model with outcome variables PaO, PaCO and [A-a] DO was used.
In both groups the best oxygenation was found in SIT. The worst oxygenation (highest [A-a] DO value) occurred in group A in CON compared with IPS (59.4±7.6 vs 49.0±7.5 mm Hg, p<0.001) and in group B in IPS compared with CON (51.0±8.7 vs 39.5±9.2 mm Hg, p<0.001). Also, PaCO showed significant differences in both groups in IPS compared with CON (p=0.002).
Patients with large-sized effusions exhibit the worst oxygenation when lying on the side contralateral to the effusion, while those with small-sized effusions exhibit the worst oxygenation when lying on the side ipsilateral to the effusion.
关于体位对胸腔积液中氧合的影响，文献中出现了不一致和相互矛盾的结果。
我们试图阐明无实质疾病的患者胸腔积液量是否是体位引起氧合参数变化的主要决定因素。我们研究了 62 名年龄为 65.3±7.8 岁（平均值±标准差）的自主呼吸患者，其中 36 名患者有大量和巨大量胸腔积液（A 组），26 名患者有少量和中量胸腔积液（B 组）。在每种体位下，至少放松 20 分钟后，测定动脉血气，分别为坐位（SIT）、仰卧位（SUP）、积液侧同侧（IPS）和对侧（CON）。A 组和 B 组的分组是根据后前位胸部 X 线片上第六前肋上缘以上的液体面线位置有意设定的。采用双因素方差分析模型，以 PaO、PaCO 和 [A-a] DO 为观察指标。
在两组中，SIT 时氧合最好。A 组在 CON 时的氧合最差（最高的 [A-a] DO 值），与 IPS 相比（59.4±7.6 与 49.0±7.5mmHg，p<0.001），B 组在 IPS 时与 CON 相比（51.0±8.7 与 39.5±9.2mmHg，p<0.001）。此外，两组患者在 IPS 时的 PaCO 与 CON 相比均有显著差异（p=0.002）。
大量胸腔积液患者侧卧时氧合最差，而小量胸腔积液患者侧卧时氧合最差。
