Emergency Department, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar.
Department of Epidemiology & Preventive Medicine, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia.
Acad Emerg Med. 2018 Oct;25(10):1129-1137. doi: 10.1111/acem.13432. Epub 2018 May 28.
The ability of emergency physicians (EPs) to identify hydronephrosis using point-of-care ultrasound (POCUS) has been assessed in the past using computed tomography (CT) scans as the reference standard. We aimed to determine the ability of EPs to identify and grade hydronephrosis on POCUS using the consensus interpretation of POCUS by emergency radiologists as the reference standard.
The study was conducted at an urban academic emergency department (ED) as a secondary analysis of previously collected ultrasound data from the EP-performed POCUS databank. Patients were eligible for inclusion if they had both POCUS and CT scanning performed during the index ED visit. Two board-certified emergency radiologists and six EPs interpreted each POCUS study independently. The interpretations were compared with the consensus interpretation by emergency radiologists. Additionally, the POCUS interpretations were also compared with the corresponding CT findings. Institutional approval was obtained for conducting this study. All the analyses were performed using Stata MP 14.0 (StataCorp).
A total of 651 patient image-data sets were eligible for inclusion in this study. Hydronephrosis was reported in 69.6% of POCUS examinations by radiologists and 72.7% of CT scans (p = 0.22). Using the consensus radiology interpretation of POCUS as the reference standard, EPs had an overall sensitivity of 85.7% (95% confidence interval [CI] = 84.3%-87.0%), specificity of 65.9% (95% CI = 63.1%-68.7%), positive likelihood ratio of 2.5 (95% CI = 2.3-2.7), and negative likelihood ratio of 0.22 (95% CI = 0.19-0.24) for hydronephrosis. When using CT scan as the reference standard, the EPs had an overall sensitivity of 81.1% (95% CI = 79.6% to 82.5%), specificity of 59.4% (95% CI = 56.4%-62.5%), positive likelihood ratio of 2.0 (95% CI = 1.8-2.2), and negative likelihood ratio of 0.32 (95% CI = 0.29-0.35) for hydronephrosis. The specificity of EPs was improved to 94.6% (95% CI = 93.7%-95.4%) for categorizing the degree of hydronephrosis as "moderate or severe" versus "none or mild," with positive likelihood ratio of 6.33 (95% CI = 5.3-7.5) and negative likelihood ratio of 0.69 (95% CI = 0.66-0.73).
Emergency physicians were found to have moderate to high sensitivity for identifying hydronephrosis on POCUS when compared with the consensus interpretation of the same studies by emergency radiologists. These POCUS findings by EPs produced more definitive results when at least moderate degree of hydronephrosis was present.
过去使用计算机断层扫描（CT）作为参考标准来评估急诊医师（EP）使用即时超声（POCUS）识别肾积水的能力。我们旨在确定 EP 使用急诊放射科医生的 POCUS 共识解读来识别和分级 POCUS 中的肾积水的能力，作为参考标准。
这项研究在城市学术急诊部门进行，是对先前从 EP 执行的 POCUS 数据库中收集的超声数据进行的二次分析。如果患者在就诊期间同时进行了 POCUS 和 CT 扫描，则符合纳入标准。两名经过董事会认证的急诊放射科医生和六名 EP 独立解读了每一项 POCUS 研究。解读结果与放射科医生的共识解读进行了比较。此外，还将 POCUS 解读结果与相应的 CT 结果进行了比较。进行这项研究获得了机构批准。所有分析均使用 Stata MP 14.0（StataCorp）进行。
共有 651 个患者的图像数据集符合纳入本研究的条件。放射科医生在 69.6%的 POCUS 检查中报告了肾积水，而 CT 扫描的报告率为 72.7%（p=0.22）。使用放射科医生的 POCUS 共识解读作为参考标准，EP 对肾积水的总体敏感性为 85.7%（95%可信区间[CI]：84.3%-87.0%），特异性为 65.9%（95% CI：63.1%-68.7%），阳性似然比为 2.5（95% CI：2.3-2.7），阴性似然比为 0.22（95% CI：0.19-0.24）。当使用 CT 扫描作为参考标准时，EP 对肾积水的总体敏感性为 81.1%（95% CI：79.6%至 82.5%），特异性为 59.4%（95% CI：56.4%-62.5%），阳性似然比为 2.0（95% CI：1.8-2.2），阴性似然比为 0.32（95% CI：0.29-0.35）。EP 对肾积水程度为“中度或重度”与“无或轻度”的分类特异性提高到 94.6%（95% CI：93.7%-95.4%），阳性似然比为 6.33（95% CI：5.3-7.5），阴性似然比为 0.69（95% CI：0.66-0.73）。
与急诊放射科医生对同一研究的共识解读相比，EP 在使用 POCUS 识别肾积水时被发现具有中等至高的敏感性。当存在至少中度肾积水时，这些由 EP 产生的 POCUS 结果更具确定性。
