Department of Pediatrics, Fundación Santa Fe de Bogotá, Bogotá, Colombia.
Departments of Pediatrics, Clinical Epidemiology, and Biostatistics, Pontificia Universidad Javeriana, Bogotá, Colombia.
High Alt Med Biol. 2020 Jun;21(2):114-125. doi: 10.1089/ham.2019.0077. Epub 2020 Apr 2.
It is well known that oxygen saturation as measured by pulse oximetry (SpO) decreases as altitude increases. However, how SpO changes across childhood, and more specifically during sleep/wake states, at different high altitudes are less well understood. We aimed to perform a systematic review of all studies with direct SpO measurement in healthy children living at high altitude (>2500 meters above sea level) to address these questions. MEDLINE, EMBASE, and SciELO databases were searched up to December 2018. Two independent reviewers screened the literature and extracted relevant data. Of 194 references, 20 studies met the eligibility criteria. Meta-analysis was not possible due to the use of different oximeters and/or protocols for data acquisition and reporting of different SpO central tendency and dispersion measures. The most relevant findings from the data were: (1) SpO is lower as altitude increases; (2) at high altitude, SpO improves with age through childhood; (3) SpO is lower during sleep and feeding in comparison to when awake, this SpO gap between wake and sleep states is more evident in the first months of life and narrows later in life; (4) SpO dispersion (interindividual variation) is higher at younger ages, and more so during sleep; (5) In 6/20 studies, the SpO values were nonnormally distributed with a consistent left skew. At high altitude, the mean/median SpO increases in children with aging; a significant gap between wake and sleep states is seen in the first months of life, which narrows as the infant gets older; SpO dispersion at high altitude is wider at younger ages; at high altitude, SpO shows a nonnormal distribution skewed to the left; this bias becomes more evident as altitude increases, at younger ages and during sleep.
众所周知，脉搏血氧饱和度（SpO）的测量值随海拔升高而降低。然而，在不同的高海拔地区，SpO 在儿童期的变化情况，特别是在睡眠/清醒状态下的变化情况，人们了解得还不够充分。我们旨在对所有在高海拔地区（海拔 2500 米以上）生活的健康儿童进行直接 SpO 测量的研究进行系统综述，以解答这些问题。我们检索了 MEDLINE、EMBASE 和 SciELO 数据库，截至 2018 年 12 月。两位独立的审查员筛选了文献并提取了相关数据。在 194 篇参考文献中，有 20 项研究符合纳入标准。由于使用了不同的血氧计和/或数据采集协议，以及报告不同 SpO 集中趋势和分散度测量值的方法不同，因此无法进行荟萃分析。从数据中得出的最相关发现包括：（1）SpO 随海拔升高而降低；（2）在高海拔地区，SpO 在儿童期随年龄增长而改善；（3）与清醒时相比，睡眠和进食时 SpO 更低，这种清醒和睡眠状态之间的 SpO 差距在生命的头几个月更为明显，随着生命的延续而缩小；（4）SpO 分散度（个体间变异）在较小时更高，在睡眠时更为明显；（5）在 6/20 项研究中，SpO 值呈非正态分布，且存在一致的左偏。在高海拔地区，随着儿童年龄的增长，SpO 的平均值/中位数增加；在生命的头几个月，清醒和睡眠状态之间存在显著差异，随着婴儿年龄的增长，这种差异逐渐缩小；在高海拔地区，SpO 分散度在较小时更大；在高海拔地区，SpO 呈左偏的非正态分布；随着海拔升高、年龄减小和睡眠时，这种偏倚变得更加明显。
