Pulmonary gas exchange and acid-base state at 5,260 m in high-altitude Bolivians and acclimatized lowlanders.
Pulmonary gas exchange and acid-base state at 5,260 m in high-altitude Bolivians and acclimatized lowlanders.
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高海拔玻利维亚人和适应的低地人在 5,260 m 处的肺气体交换和酸碱状态。
DOI：
10.1152/japplphysiol.00093.2001
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
Saltin,Bengt
中科院分区：
文献类型：
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作者：
Wagner,PeterD;Araoz,Mauricio;Boushel,Robert;Calbet,JoséAL;Jessen,Birgitte;Rådegran,Göran;Spielvogel,Hilde;Søndegaard,Hans;Wagner,Harrieth;Saltin,Bengt
对9名适应海拔5，260米9周的丹麦低地人（L）和7名急性到达该海拔高度的拉巴斯（海拔3，600 - 4，100米）的玻利维亚土著居民（N）的肺气体交换和酸碱状态进行了比较。我们评估了动脉pH值的正常状态，并评估了休息时和呼吸室内空气和55%O2时运动高峰期的肺气体交换和酸碱平衡。尽管在海拔5,260米处停留了9周，肾脏有大量碳酸氢盐排泄（动脉血浆HCO 3 −浓度= 15.1 meq/l），但L的静息动脉pH值为7.48 ± 0.007（显著大于7.40）。另一方面，在2小时内从3，600 - 4，100米上升到5，260米后，N的动脉pH仅为7.43 ± 0.004（尽管动脉氧饱和度为77%）。两组呼吸空气的最大功率输出相似，而在55%O2只有L显示出显着增加。在空气中运动时，L组动脉Pco 2比N组低8 Torr（P< 0.001），但Po 2相同，在最大氧摄取量时，N组肺泡-动脉Po 2差（5.3 ± 1.3 Torr）低于L组（10.5 ± 0.8 Torr），P= 0.004。计算的O2扩散能力是40%，高于在L中，如果参考最大高氧工作，能力是73%，N。缓冲乳酸是更大的N，与20%的基础赤字增加每毫摩尔每升上升乳酸。这些数据表明，即使在5，260米的9周后，L仍持续性水肿。在N中，数据显示：1）与呼吸55%O2相比，呼吸5,260米空气时运动能力无显著降低;2）对急性低氧血症的缓解反应非常小（根据动脉pH值和动脉对高氧的反应来判断）3）运动时肺弥散量大于L，尽管通气量较低，但仍能维持动脉Po 2; 4）乳酸缓冲性好。这些结果支持并扩展了以前在低得多的海拔地区进行的关于这些和其他高海拔土著群体肺功能适应的类似观察。
Pulmonary gas exchange and acid-base state were compared in nine Danish lowlanders (L) acclimatized to 5,260 m for 9 wk and seven native Bolivian residents (N) of La Paz (altitude 3,600–4,100 m) brought acutely to this altitude. We evaluated normalcy of arterial pH and assessed pulmonary gas exchange and acid-base balance at rest and during peak exercise when breathing room air and 55% O2. Despite 9 wk at 5,260 m and considerable renal bicarbonate excretion (arterial plasma HCO3−concentration = 15.1 meq/l), resting arterial pH in L was 7.48 ± 0.007 (significantly greater than 7.40). On the other hand, arterial pH in N was only 7.43 ± 0.004 (despite arterial O2saturation of 77%) after ascent from 3,600–4,100 to 5,260 m in 2 h. Maximal power output was similar in the two groups breathing air, whereas on 55% O2only L showed a significant increase. During exercise in air, arterial Pco2was 8 Torr lower in L than in N (P< 0.001), yet Po2was the same such that, at maximal O2uptake,alveolar-arterial Po2difference was lower in N (5.3 ± 1.3 Torr) than in L (10.5 ± 0.8 Torr),P= 0.004. Calculated O2diffusing capacity was 40% higher in N than in L and, if referenced to maximal hyperoxic work, capacity was 73% greater in N. Buffering of lactic acid was greater in N, with 20% less increase in base deficit per millimole per liter rise in lactate. These data show in L persistent alkalosis even after 9 wk at 5,260 m. In N, the data show1) insignificant reduction in exercise capacity when breathing air at 5,260 m compared with breathing 55% O2;2) very little ventilatory response to acute hypoxemia (judged by arterial pH and arterial Pco2responses to hyperoxia);3) during exercise, greater pulmonary diffusing capacity than in L, allowing maintenance of arterial Po2despite lower ventilation; and4) better buffering of lactic acid. These results support and extend similar observations concerning adaptation in lung function in these and other high-altitude native groups previously performed at much lower altitudes.