Department of Health Sciences, Mid Sweden University, Östersund, Sweden.
Swedish Winter Sports Research Centre, Mid Sweden University, Ostersund, Sweden.
High Alt Med Biol. 2020 Mar;21(1):84-91. doi: 10.1089/ham.2019.0028.
The human spleen can contract and transiently boost the blood with stored erythrocytes. We measured spleen volume and contraction during apneas in two groups, each containing 12 Caucasian participants (each 3 women): one group planning to summit Mt. Everest (8848 m; "Climbers") and another trekking to Everest Base Camp (5300 m; "Trekkers"). Tests were done in Kathmandu (1370 m) 1-3 days after arrival, before the Climb/Trek. Age, height, weight, vital capacity, resting heart rate, and arterial oxygen saturation were similar between groups (not significant). After 15 minutes of sitting rest, all participants performed a 1-minute apnea and, after 2 minutes of rest, 1 maximal duration apnea was performed. Six of the climbers did a third apnea and hemoglobin concentration (Hb) was measured. Three axial spleen diameters were measured by ultrasonic imaging before and after the apneas for spleen volume calculation. Mean (standard deviation) baseline spleen volume was larger in Climbers [367 (181) mL] than in Trekkers [228 (70) mL; = 0.022]. Spleen contraction occurred during apneas in both groups, with about twice the magnitude in Climbers. Three apneas in six of the Climbers resulted in a spleen volume reduction from 348 (145) to 202 (91) mL ( = 0.005) and an Hb elevation from 147.9 (13.1) to 153.3 (11.3) g/L ( = 0.024). Maximal apneic duration was longer in Climbers [88 (23) seconds vs. 67 (18) seconds in Trekkers; = 0.023]. We concluded that a large spleen characterizes Climbers, suggesting that spleen function may be important for high-altitude climbing performance.
人类脾脏可以收缩并短暂增加储存的红细胞的血液供应。我们在两组人群中测量了在呼吸暂停期间的脾脏体积和收缩，每组各有 12 名高加索参与者（各 3 名女性）：一组计划攀登珠穆朗玛峰（8848 米；“登山者”），另一组徒步前往珠穆朗玛峰大本营（5300 米；“徒步旅行者”）。测试是在加德满都（1370 米）进行的，在登山/徒步旅行前的 1-3 天内进行，参与者在休息 15 分钟后进行了 1 分钟的呼吸暂停，然后休息 2 分钟后进行了 1 次最长持续时间的呼吸暂停。6 名登山者进行了第三次呼吸暂停，并且测量了血红蛋白浓度（Hb）。在进行呼吸暂停前后，通过超声成像测量了脾脏的 3 个轴向直径，用于计算脾脏体积。登山者的平均（标准差）基线脾脏体积较大[367（181）mL]，比徒步旅行者[228（70）mL； = 0.022]大。两组人群在呼吸暂停期间均发生了脾脏收缩，登山者的收缩幅度大约是徒步旅行者的两倍。在 6 名登山者中的 3 次呼吸暂停导致脾脏体积从 348（145）降至 202（91）mL（ = 0.005），血红蛋白从 147.9（13.1）升高至 153.3（11.3）g/L（ = 0.024）。登山者的最大呼吸暂停时间更长[88（23）秒与徒步旅行者的 67（18）秒； = 0.023]。我们得出结论，脾脏较大的特征是登山者，这表明脾脏功能可能对高海拔登山表现很重要。
