Kaminecki Inna, Huang Deborah M, Shipman Peter C, Gibson Robert W
From the Augusta University, Augusta, GA.
Pediatr Emerg Care. 2023 Oct 1;39(10):786-796. doi: 10.1097/PEC.0000000000003025. Epub 2023 Aug 17.
Accurate estimation of the degree of dehydration remains a diagnostic challenge. The primary objective was to systematically review the literature on the role of ultrasound in assessment of the degree of dehydration in children.
Data sources included Ovid MEDLINE, Web of Science Core Collection, Current Index to Nursing and Allied Health Literature, Cochrane Library, ClinicalTrials.gov , and Trip Pro Database. Two independent reviewers used screening protocol to include articles on assessment of dehydration in children with the use of point-of-care ultrasonography (POCUS). The level of evidence was assessed in accordance with the "The Oxford 2011 Levels of Evidence." The Quality Assessment of Diagnostic Accuracy Studies-2 tool was used to evaluate risk of bias.
We identified 108 studies, and 8 studies met our inclusion criteria. All studies were prospective cohort studies (level of evidence, 3-4). The authors of 5 studies used difference between ill weight and weight after rehydration as the reference standard for dehydration, and the authors of 3 studies used clinical dehydration scale. Two studies from the United States showed acceptable areas under the curve for inferior vena cava to aorta (IVC/Ao) diameter ratio at 0.72 and 0.73 for prediction of significant dehydration (>5% weight loss). The IVC/Ao ratio with cut-off at 0.8 had sensitivity of 67% and 86% and specificity of 71% and 56% for prediction of significant dehydration. Studies from the resource-limited settings were more heterogeneous. One study with acceptable risk of biases reported poor sensitivity (67%) and specificity (49%) of Ao/IVC ratio with cut-off of 2.0 for predicting severe dehydration (>9% weight loss) with area under the curve at 0.6. Three studies showed increase in IVC diameter with fluid resuscitation with mean change in IVC diameter by 30% in children with significant dehydration (>5% weight loss) and by 22% without significant dehydration (<5% weight loss). Metaanalysis was not completed due to high heterogeneity.
This study showed that the quantity and quality of research on the application of POCUS for the assessment of dehydration in children is limited. There is no criterion standard for assessing the degree of dehydration and no universal definition of the degree of dehydration. Thus, more methodologically rigorous studies are required. Current systematic review does not support the routine use of US to determine the severity of dehydration in children. Despite these limitations, the use of POCUS in children with dehydration demonstrates potential. Given the clear increase in IVC size with rehydration, repeated IVC US scans may be helpful in guiding fluid resuscitation in children with dehydration. From different proposed US parameters, IVC/Ao ratio has better diagnostic accuracy in detecting significant dehydration than Ao/IVC ratio and IVC collapsibility index. Despite low to moderate diagnostic performance, US still showed better assessment of dehydration than physician gestalt and World Health Organization score.
准确估计脱水程度仍然是一项诊断挑战。主要目的是系统回顾关于超声在评估儿童脱水程度中作用的文献。
数据来源包括Ovid MEDLINE、科学引文索引核心合集、护理与联合健康文献当前索引、考克兰图书馆、ClinicalTrials.gov和Trip Pro数据库。两名独立评审员使用筛选方案纳入关于使用即时超声检查（POCUS）评估儿童脱水的文章。依据“2011年牛津证据水平”评估证据水平。使用诊断准确性研究质量评估-2工具评估偏倚风险。
我们识别出108项研究，8项研究符合我们的纳入标准。所有研究均为前瞻性队列研究（证据水平为3 - 4）。5项研究的作者将患病时体重与补液后体重的差值作为脱水的参考标准，3项研究的作者使用临床脱水量表。美国的两项研究显示，下腔静脉与主动脉（IVC/Ao）直径比预测严重脱水（体重减轻>5%）时曲线下面积可接受，分别为0.72和0.73。IVC/Ao比值截断值为0.8时，预测严重脱水的敏感性分别为67%和86%，特异性分别为71%和56%。资源有限地区的研究更具异质性。一项偏倚风险可接受的研究报告称，Ao/IVC比值截断值为2.0时，预测严重脱水（体重减轻>9%）的敏感性较差（67%），特异性为49%，曲线下面积为0.6。三项研究显示，补液后IVC直径增加，严重脱水（体重减轻>5%）儿童的IVC直径平均变化30%，无严重脱水（体重减轻<5%）儿童的IVC直径平均变化22%。由于异质性高，未完成荟萃分析。
本研究表明，关于POCUS用于评估儿童脱水的研究数量和质量有限。评估脱水程度没有标准规范，脱水程度也没有统一的定义。因此，需要更多方法学严谨的研究。当前的系统评价不支持常规使用超声来确定儿童脱水的严重程度。尽管有这些局限性，但POCUS在脱水儿童中的应用显示出潜力。鉴于补液后IVC大小明显增加，重复进行IVC超声扫描可能有助于指导脱水儿童的液体复苏。从不同提出的超声参数来看，IVC/Ao比值在检测严重脱水方面比Ao/IVC比值和IVC塌陷指数具有更好的诊断准确性。尽管诊断性能低至中等，但超声对脱水的评估仍优于医生的整体判断和世界卫生组织评分。
