Spicuzza L, Casiraghi N, Gamboa A, Keyl C, Schneider A, Mori A, Leon-Velarde F, Di Maria G U, Bernardi L
Dept of Internal Medicine and Medical Specialities, University of Catania, Italy.
Eur Respir J. 2004 Jan;23(1):41-6. doi: 10.1183/09031936.03.00000703.
To determine whether nocturnal hypoxaemia contributes to the excessive erythrocytosis (EE) in Andean natives, standard polysomnographies were performed in 10 patients with EE and in 10 controls (mean haematocrit 76.6 +/- 1.3% and 5.4 +/- 0.8%, respectively) living at an altitude of 4,380 m. In addition, the effect of O2 administration for 1 h prior to sleep, and the relationship between the hypoxic/hypercapnic ventilatory response and the apnoea/hypopnoea index (AHI) during sleep were studied. Awake arterial oxygen saturation (Sa,O2) was significantly lower in patients with EE than in controls (83.7 +/- 0.3% versus 85.6 +/- 0.4%). In both groups, the mean Sa,O2 significantly decreased during sleep (to 80.0 +/- 0.8% in EE and to 82.8 +/- 0.5% in controls). The mean Sa,O2 values remained significantly lower in patients with EE than in controls at all times of the night, and patients with EE spent significantly more time than the controls with an Sa,O2 of <80%. There were no differences between the two groups in the number and duration of the apnoeas/hypopnoeas. None of these variables were affected by O2 administration. In both groups the AHI positively correlated with the hypercapnic ventilatory response. Andean natives undergo minor respiratory disorders during sleep. The reduction in oxygen saturation found in subjects with excessive erythrocytosis was small, yet consistent and potentially important, as it remained below the threshold known for the increase in erythropoietin stimulation. This may be an important factor promoting erythropoiesis, but its relevance needs to be further explored.
为了确定夜间低氧血症是否导致安第斯原住民的红细胞增多症（EE），对10例EE患者和10例对照组（平均血细胞比容分别为76.6±1.3%和5.4±0.8%）进行了标准多导睡眠图检查，这些患者和对照组生活在海拔4380米处。此外，还研究了睡前1小时吸氧的效果，以及睡眠期间低氧/高碳酸血症通气反应与呼吸暂停/低通气指数（AHI）之间的关系。EE患者清醒时的动脉血氧饱和度（Sa,O2）显著低于对照组（83.7±0.3%对85.6±0.4%）。在两组中，睡眠期间平均Sa,O2均显著下降（EE组降至80.0±0.8%，对照组降至82.8±0.5%）。EE患者夜间各时段的平均Sa,O2值仍显著低于对照组，且EE患者Sa,O2<80%的时间显著多于对照组。两组的呼吸暂停/低通气次数和持续时间无差异。这些变量均未受吸氧的影响。两组中AHI均与高碳酸血症通气反应呈正相关。安第斯原住民睡眠期间会出现轻微的呼吸紊乱。红细胞增多症患者的氧饱和度下降幅度较小，但持续存在且可能具有重要意义，因为其仍低于已知可增加促红细胞生成素刺激的阈值。这可能是促进红细胞生成的一个重要因素，但其相关性有待进一步探索。
