Lang Morin, Vizcaíno-Muñoz Guillem, Jopia Paulina, Silva-Urra Juan, Viscor Ginés
Department of Rehabilitation Sciences and Human Movement, Faculty of Health Sciences, University of Antofagasta, Antofagasta 1240000, Chile.
Physiology Section, Department of Cell Biology, Physiology and Immunology, Faculty of Biology, Universitat de Barcelona, E-08028 Barcelona, Spain.
Life (Basel). 2021 Sep 24;11(10):1009. doi: 10.3390/life11101009.
During the last decades, the number of lowland children exposed to high altitude (HA) has increased drastically. Several factors may influence the development of illness after acute HA exposure on children and adolescent populations, such as altitude reached, ascent velocity, time spent at altitude and, especially, their age. The main goal of this study was to evaluate the resting cardiorespiratory physiological and submaximal exercise responses under natural HA conditions by means of the six-minute walking test (six MWT). Secondly, we aimed to identify the signs and symptoms associated with acute mountain sickness (AMS) onset after acute HA exposure in children and adolescents. Forty-two children and adolescents, 18 boys and 24 girls aged from 11 to 15 years old, participated in this study, which was performed at sea level (SL) and during the first 42 h at HA (3330 m). The Lake Louise score (LLS) was recorded in order to evaluate the evolution of AMS symptoms. Submaximal exercise tests (six MWT) were performed at SL and HA. Physiological parameters such as heart rate, systolic and diastolic blood pressure, respiratory rate and arterialized oxygen saturation were measured at rest and after ending exercise testing at the two altitudes. After acute HA exposure, the participants showed lower arterial oxygen saturation levels at rest and after the submaximal test compared to SL ( < 0.001). Resting heart rate, respiratory rate and diastolic blood pressure presented higher values at HA ( < 0.01). Moreover, heart rate, diastolic blood pressure and dyspnea values increased before, during and after exercise at HA ( < 0.01). Moreover, submaximal exercise performance decreased at HA ( < 0.001). The AMS incidence at HA ranged from 9.5% to 19%, with mild to moderate symptoms. In conclusion, acute HA exposure in children and adolescent individuals produces an increase in basal cardiorespiratory parameters and a decrement in arterial oxygen saturation. Moreover, cardiorespiratory parameters increase during submaximal exercise at HA. Mild to moderate symptoms of AMS at 3330 m and adequate cardiovascular responses to submaximal exercise do not contraindicate the ascension of children and adolescents to that altitude, at least for a limited period of time.
在过去几十年里，暴露于高海拔地区（HA）的低地儿童数量急剧增加。有几个因素可能会影响儿童和青少年群体急性暴露于高海拔地区后疾病的发展，比如到达的海拔高度、上升速度、在高海拔地区停留的时间，尤其是他们的年龄。本研究的主要目的是通过六分钟步行试验（six MWT）评估自然高海拔条件下的静息心肺生理和次最大运动反应。其次，我们旨在确定儿童和青少年急性暴露于高海拔地区后与急性高原病（AMS）发作相关的体征和症状。42名儿童和青少年，18名男孩和24名女孩，年龄在11至15岁之间，参与了本研究，该研究在海平面（SL）以及在高海拔地区（3330米）的头42小时内进行。记录了路易斯湖评分（LLS）以评估急性高原病症状的演变。在海平面和高海拔地区进行了次最大运动试验（六分钟步行试验）。在两个海拔高度的静息状态以及运动试验结束后，测量了心率、收缩压和舒张压、呼吸频率和动脉化血氧饱和度等生理参数。急性暴露于高海拔地区后，与海平面相比，参与者在静息状态和次最大试验后的动脉血氧饱和度水平较低（<0.001）。静息心率、呼吸频率和舒张压在高海拔地区呈现较高值（<0.01）。此外，在高海拔地区运动前、运动期间和运动后的心率、舒张压和呼吸困难值增加（<0.01）。此外，高海拔地区的次最大运动表现下降（<0.001）。高海拔地区急性高原病的发病率在9.5%至19%之间，症状为轻度至中度。总之，儿童和青少年个体急性暴露于高海拔地区会导致基础心肺参数增加以及动脉血氧饱和度下降。此外，高海拔地区次最大运动期间心肺参数会增加。在3330米处出现的轻度至中度急性高原病症状以及对次最大运动的适当心血管反应并不妨碍儿童和青少年升至该海拔高度，至少在有限的时间段内如此。
