Härtel Julian Alexander, Müller Nicole, Breuer Johannes, Jordan Jens, Tank Jens, Bros Janina, Seeger Benedikt, Zollmann Emily, Bloch Wilhelm, Grau Marijke
Department for Pediatric Cardiology, University Hospital Bonn, 53127 Bonn, Germany.
Institute of Aerospace Medicine, German Aerospace Center e.V. (DLR), 51147 Cologne, Germany.
Metabolites. 2022 Oct 26;12(11):1025. doi: 10.3390/metabo12111025.
Patients with Fontan circulation are particularly dependent on low pulmonary vascular resistance because their lungs are passively perfused. Hypoxia drives pulmonary vasoconstriction; thus, red blood cell (RBC) deformability and stability of hematological parameters might be of particular importance, because alterations during hypoxia might further influence circulation. This study aimed to measure respective parameters in patients with Fontan circulation exposed to normobaric hypoxia. A total of 18 patients with Fontan circulation (16 to 38 years) were exposed to normobaric hypoxia (15.2% ambient oxygen). Blood samples were taken in normoxia, after 24 h in hypoxia, and 60 min after return to normoxia. Blood count, RBC age distribution, EPO, RBC deformability, marker of RBC nitric oxide, oxidative state, and RBC ATP were measured. Hypoxia increased oxidative stress in RBC, but without affecting RBC deformability. RBC age distribution remained unaffected, although EPO concentrations increased, followed by a rise in reticulocyte count at an already high hematocrit. NO metabolism was not affected by hypoxia. Modest normobaric hypoxia for 24 h did not impair RBC deformability in patients with Fontan circulation; however, the oxidative system seemed to be stressed. Given the high baseline Hct in these patients, hypoxia-induced erythropoiesis could adversely affect rheology with more prolonged hypoxia exposure.
接受Fontan循环手术的患者尤其依赖低肺血管阻力，因为他们的肺部是被动灌注的。缺氧会导致肺血管收缩；因此，红细胞（RBC）的可变形性和血液学参数的稳定性可能尤为重要，因为缺氧期间的变化可能会进一步影响循环。本研究旨在测量接受Fontan循环手术的患者在常压缺氧情况下的各项参数。共有18例接受Fontan循环手术的患者（年龄在16至38岁之间）接受了常压缺氧（环境氧含量为15.2%）。在常氧状态下、缺氧24小时后以及恢复常氧60分钟后采集血样。测量了血细胞计数、红细胞年龄分布、促红细胞生成素（EPO）、红细胞可变形性、红细胞一氧化氮标志物、氧化状态和红细胞三磷酸腺苷（ATP）。缺氧增加了红细胞中的氧化应激，但未影响红细胞的可变形性。尽管EPO浓度升高，随后在已经很高的血细胞比容水平下网织红细胞计数增加，但红细胞年龄分布未受影响。一氧化氮代谢不受缺氧影响。对接受Fontan循环手术的患者进行24小时的适度常压缺氧不会损害红细胞的可变形性；然而，氧化系统似乎受到了压力。鉴于这些患者的基线血细胞比容较高，长时间暴露于缺氧环境下，缺氧诱导的红细胞生成可能会对血液流变学产生不利影响。
