从储存的血液中减弱的O2卸载导致组织中扩散有限的O2释放:来自人类脏的证据
Richard Dumbill1,2, Julija Rabcuka3, John Fallon1,2
1Nuffield Department of Surgery, University of Oxford, Oxford, United Kingdom.
Blood
|December 4, 2023
概括
储存的红细胞 (RBC) 损害了氧气的释放,使得氧气输送扩散有限. 复原红细胞改善了脏氧气扩散和皮质氧气水平,突出了红细胞动力学.
科学领域:
- 生理学 生理学 生理学
- 生物医学工程 生物医学工程
- 输血医学 输血医学
背景情况:
- 输送氧气到组织通常被认为是 perfusion-limited,重点是血流和氧含量.
- 红细胞 (RBC) 氧气卸载动力学通常被认为是快速的,而不是限制因素.
- 储存的红血细胞可能会经历动力衰减,可能会将氧气运输从 perfusion-limited转变为 diffusion-limited.
研究的目的:
- 为了调查储存的红细胞释放的氧气是否会在活跃的人类脏中受到扩散限制.
- 评估RBC氧气卸载动力学对脏氧气输送和呼吸的影响.
- 评估再生储存红细胞的潜力,以改善氧气扩散和器官功能.
主要方法:
- 人的脏被正常热地注入储存的血液.
- 呼吸与RBC氧气卸载时间常数相关.
- 不适合移植的脏被灌注了交替储存和再生的红细胞,以控制其他变量.
主要成果:
- 呼吸与红细胞氧气卸载时间常数相反相关.
- 当考虑红细胞释放率时,脏呼吸率仅与动脉O2输送相关.
- 复原的红血细胞改善了脏的氧气扩散能力,并将皮质氧的部分压力提高了60%.
结论:
- 对组织的氧气输送可以通过储存的红细胞变得扩散受限.
- 红细胞氧气卸载动力学对于有效的氧气运输至关重要,特别是在临床场景中,如ex vivo器官输液和输血.
- 红细胞再生可以挽救受损的氧气卸载动力学,并改善器官的氧化.
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