Department of Neonatal Medicine, University Hospital Southampton NHS Foundation Trust, Southampton, UK
NIHR Southampton Biomedical Research Centre, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK.
Arch Dis Child Fetal Neonatal Ed. 2021 Sep;106(5):542-548. doi: 10.1136/archdischild-2020-321112. Epub 2021 Mar 31.
Total body water (TBW) is one component of fat-free mass and changes in TBW are influenced by fluid shifts (especially during transition to postnatal life), electrolyte balance and nutritional status. Normal values for term-born neonates and preterm infants at birth have not been defined in large cohorts, limiting investigation into its monitoring and use in clinical practice.
To systematically review the evidence base for percentage of TBW in term-born infants, quantify the effect of prematurity on TBW at birth, and describe normal progression of TBW over time in preterm infants.
Systematic review of Medline, Web of Science Core Collection and EBSCO-CINAHL (January 1946 to January 2020). Included articles used dilutional methods to assess TBW.
Searches identified 2349 articles of which 22 included data suitable for analysis. Mean TBW in term-born newborns was 73.8% (95% CI 72.47% to 75.06%, 15 studies, 433 infants). Meta-regression showed that TBW was higher in preterm infants (up to 90% at 26 weeks gestation, dropping to 75% at 36 weeks corrected gestation) and was negatively correlated with gestation at birth, falling 1.44% per week (95% CI 0.63% to 2.24%, 9 studies, 179 infants). Analysis of TBW over time during the ex utero growth of preterm infants was not possible due to paucity of data.
This review defines the normal TBW percentage in term-born infants and confirms and quantifies previous findings that preterm infants have a higher TBW percentage.
全身水（TBW）是去脂体重的一个组成部分，TBW 的变化受液体转移（尤其是在过渡到产后生活期间）、电解质平衡和营养状况的影响。在大型队列中，尚未定义足月新生儿和早产儿出生时的 TBW 正常值，这限制了对其监测的研究及其在临床实践中的应用。
系统综述足月新生儿 TBW 百分比的证据基础，量化早产对出生时 TBW 的影响，并描述早产儿 TBW 随时间的正常变化。
对 Medline、Web of Science Core Collection 和 EBSCO-CINAHL（1946 年 1 月至 2020 年 1 月）进行系统综述。纳入的文章使用稀释法评估 TBW。
搜索共确定了 2349 篇文章，其中 22 篇文章包含适合分析的数据。足月新生儿的平均 TBW 为 73.8%（95%CI 72.47%至 75.06%，15 项研究，433 名婴儿）。Meta 回归显示，早产儿的 TBW 更高（在 26 周妊娠时高达 90%，在 36 周校正妊娠时降至 75%），且与出生时的胎龄呈负相关，每周下降 1.44%（95%CI 0.63%至 2.24%，9 项研究，179 名婴儿）。由于数据匮乏，无法对早产儿宫外生长期间的 TBW 进行时间分析。
本综述定义了足月新生儿的正常 TBW 百分比，并证实和量化了先前的发现，即早产儿的 TBW 百分比更高。
