Department of Pathology, Beth Israel Deaconess Medical Center, Boston, MA, USA.
Memorial Sloan Kettering Cancer Center, Department of Laboratory Medicine, New York, NY 10065, USA.
J Appl Lab Med. 2022 May 4;7(3):788-793. doi: 10.1093/jalm/jfab156.
Modern clinical laboratory analyzers measure a hemolysis index (H-index) because test results can be inaccurate when intracellular contents from erythrocytes leak into serum or plasma. In 2020, Roche Diagnostics decreased the H-index from 90/100 to 20 for potassium, recommending that laboratories avoid using specimens with an H-index >20; however, there are a limited number of studies investigating the impact of this recommendation on patient testing.
Out of 113 916 serum or plasma potassium tests performed within a 6-month interval, 72 patients with potentially hemolyzed potassium specimens (H-index >20) and a second non-hemolyzed specimen (H-index ≤20) within 2 h were identified. The clinical impact of decreasing the H-index and the utility of applying a corrective formula for adjusting potassium results were evaluated.
The majority of initial test results either had small differences between original and corrected results that would not have affected clinical management or H-indices above the threshold previously recommended by Roche. We estimated the second sample was reported an average of 3 h 23 min after the initial sample was collected, with 95% CI [2 h 37 min to 4 h 8 min], and the median time delay was 2 h 44 min.
Our analysis does not show a clear benefit from avoiding the use of potassium specimens above an H-index threshold of 20. Our findings suggest these practices may be detrimental in terms of patient safety due to increased turnaround time for a critical analyte.
现代临床实验室分析仪会测量溶血指数（H-index），因为当红细胞内物质泄漏到血清或血浆中时，检测结果可能会不准确。罗氏诊断公司于 2020 年将钾的 H-index 从 90/100 降至 20，并建议实验室避免使用 H-index>20 的标本；然而，目前仅有少数研究调查了这一建议对患者检测的影响。
在 6 个月的时间间隔内，对 113916 例血清或血浆钾检测进行了研究，在 2 小时内，确定了 72 例潜在溶血的钾标本（H-index>20）和第二份非溶血标本（H-index≤20）。评估了降低 H-index 的临床影响和应用校正公式调整钾结果的实用性。
初始检测结果中，大部分原始结果与校正结果之间的差异较小，不会影响临床管理，或者 H-index 高于罗氏此前推荐的阈值。我们估计，第二份样本的报告时间平均比第一份样本采集后延迟 3 小时 23 分钟，95%CI[2 小时 37 分钟至 4 小时 8 分钟]，中位数延迟时间为 2 小时 44 分钟。
我们的分析并没有显示出避免使用 H-index 阈值大于 20 的钾标本的明显益处。我们的研究结果表明，由于关键分析物的周转时间增加，这些做法可能会对患者安全造成不利影响。
