Van Liew H D, Burkard M E
Department of Physiology, University at Buffalo, State University of New York 14214-3078, USA.
J Appl Physiol (1985). 1996 Jul;81(1):500-8. doi: 10.1152/jappl.1996.81.1.500.
Stabilized bubbles can pass through capillary beds, recirculate for a few minutes or hours, and carry O2 from the lungs to the tissues. Here, we develop the theory for the O2 content-PO2 relationship of bubbles and the alterations of the bubbles that are coupled to the O2 transport. We provide examples for bubbles stabilized by a slowly permeating gas; bubbles stabilized by mechanical structures may behave similarly. Because there are two mechanisms for O2 unloading (lowering of PO2 and shrinkage), the bubbles release a large fraction of their O2 content at high PO2; when pure O2 is breathed, one-half of the content of a 3-microns-radius bubble is released before PO2 falls to 500 Torr. The possibility that stabilized bubbles could become a clinical tool for therapeutic transport of O2 raises many issues to be investigated. The highunloading PO2 offers opportunities for delivering O2 by diffusion to poorly perfused regions of the tissue but also presents a hazard of O2 toxicity to perfused tissue.
稳定的气泡能够通过毛细血管床，循环几分钟或几小时，并将氧气从肺部输送到组织。在此，我们建立了气泡的氧含量与氧分压关系以及与氧运输相关的气泡变化的理论。我们给出了由缓慢渗透气体稳定的气泡的示例；由机械结构稳定的气泡可能表现相似。由于存在两种氧气卸载机制（氧分压降低和收缩），气泡在高氧分压时释放大部分氧含量；当吸入纯氧时，半径为3微米的气泡在氧分压降至500托之前会释放其一半的含量。稳定气泡可能成为氧气治疗性运输临床工具的可能性引发了许多有待研究的问题。高卸载氧分压为通过扩散向组织灌注不良区域输送氧气提供了机会，但也对灌注组织存在氧中毒的风险。
