高海拔(HA)上升会导致全身缺氧和相关的急性高山病风险。急性缺氧引起低氧通气反应(HVR),随着慢性HA暴露的增加(即,通气适应;VA)。然而,基于实验室的HVR测试在现场研究中缺乏可移植性和可行性。作为替代,我们旨在表征Fenn图上的曲线下面积(AUC)计算,通过绘制潮气末二氧化碳的便携式测量值(PETCO2${P_{\\mathrm{ETC}}{{\\mathrm{O}}_{\\mathrm{2}}}}$)与周围氧饱和度(SpO2${\{\{\mathrm{p}}}{\\mashm}到{VA}的增量其次,这些参与者在上升过程中自我给予预防性口服剂量的乙酰唑胺(Az;125mgBID;n=20)的同时,在相同的上升过程中与单独的一组进行比较.首先,上午PETCO2${P_{\\mathrm{ETC}}{\\mathrm{O}}_{\\mathrm{2}}}}$和SpO2${S_{{\\mathrm{p}}}{\\\mathrm{O}}}_{\\mathrm{2}}AUC是根据单独构建的芬恩图计算的,对表征最小的排序值进行三分类,中等,AUC的最大量级,代表高(n=15),中等(n=16),和低(n=15)的适应度。在表征响应幅度的范围之后,我们进一步证明,Az组的AUC幅度明显小于NAz组(P=0.0021),建议改善VA。这些结果表明,在改良的Fenn图上计算AUC可用于评估大组徒步旅行者在递增上升到HA期间的VA,由于与已知生理学相关的便携性和一致性,尽管这种新颖的分析方法需要在受控实验中进一步验证。重点:这项研究的中心问题是什么?评估增加向高海拔(HA)的通气适应(VA)的新颖方法学方法的特征是什么?主要发现及其重要性是什么?从修改的芬恩图计算的曲线下面积(AUC)幅度与无唑胺组相比,服用口服预防性剂量的唑乙酰胺组明显较小,建议改善VA。在HA增量上升期间,使用修改的Fenn图量化AUC对于评估大组徒步旅行者的VA是可行的,尽管这种新颖的分析方法需要在受控实验中进一步验证。
High altitude (HA) ascent imposes systemic hypoxia and associated risk of acute mountain sickness. Acute hypoxia elicits a hypoxic ventilatory response (HVR), which is augmented with chronic HA exposure (i.e., ventilatory acclimatization; VA). However, laboratory-based HVR tests lack portability and feasibility in field studies. As an alternative, we aimed to characterize area under the curve (AUC) calculations on Fenn diagrams, modified by plotting portable measurements of end-tidal carbon dioxide ( P ETC O 2 ${P_{{\\mathrm{ETC}}{{\\mathrm{O}}_{\\mathrm{2}}}}}$ ) against peripheral oxygen saturation ( S p O 2 ${S_{{\\mathrm{p}}{{\\mathrm{O}}_{\\mathrm{2}}}}}$ ) to characterize and quantify VA during incremental ascent to HA (n = 46). Secondarily, these participants were compared with a separate group following the identical ascent profile whilst self-administering a prophylactic oral dose of
acetazolamide (Az; 125 mg BID; n = 20) during ascent. First, morning P ETC O 2 ${P_{{\\mathrm{ETC}}{{\\mathrm{O}}_{\\mathrm{2}}}}}$ and S p O 2 ${S_{{\\mathrm{p}}{{\\mathrm{O}}_{\\mathrm{2}}}}}$ measurements were collected on 46
acetazolamide-free (NAz) lowland participants during an incremental ascent over 10 days to 5160 m in the Nepal Himalaya. AUC was calculated from individually constructed Fenn diagrams, with a trichotomized split on ranked values characterizing the smallest, medium, and largest magnitudes of AUC, representing high (n = 15), moderate (n = 16), and low (n = 15) degrees of acclimatization. After characterizing the range of response magnitudes, we further demonstrated that AUC magnitudes were significantly smaller in the Az group compared to the NAz group (P = 0.0021), suggesting improved VA. These results suggest that calculating AUC on modified Fenn diagrams has utility in assessing VA in large groups of trekkers during incremental ascent to HA, due to the associated portability and congruency with known physiology, although this novel analytical method requires further validation in controlled experiments. HIGHLIGHTS: What is the central question of this study? What are the characteristics of a novel methodological approach to assess ventilatory acclimatization (VA) with incremental ascent to high altitude (HA)? What is the main finding and its importance? Area under the curve (AUC) magnitudes calculated from modified Fenn diagrams were significantly smaller in trekkers taking an oral prophylactic dose of
acetazolamide compared to an
acetazolamide-free group, suggesting improved VA. During incremental HA ascent, quantifying AUC using modified Fenn diagrams is feasible to assess VA in large groups of trekkers with ascent, although this novel analytical method requires further validation in controlled experiments.