Background/objective While ammonia plays a role in the complex pathophysiology of hepatic encephalopathy (HE), serum ammonia is unreliable for both diagnosis of, and correlation with, neurological symptoms in patients with cirrhosis. We aimed to quantify ordering, cost and appropriate use of serum ammonia in a major Midwestern healthcare system. Design/method Serum ammonia ordering in adult patients presenting to a large Midwestern health system was evaluated from 1 January 2015 to 31 December 2019. Results Serum ammonia ordering was prevalent, with 20 338 tests ordered over 5 years. There were no differences in the number of inappropriate serum ammonia tests per 100 000 admissions for chronic liver disease over time (Pearson’s correlation coefficient=−0.24, p=0.70). As a proportion of total ammonia tests ordered, inappropriate tests increased over time (Pearson’s correlation coefficient=0.91, p=0.03). Inappropriate ordering was more common at community hospitals compared with the academic medical centre (99.3% vs 87.6%, p<0.001). Conclusion Despite evidence that serum ammonia levels are unreliable for the diagnosis of HE and are not associated with severity of HE in individuals with cirrhosis, ordering remains prevalent, contributing to waste and potential harm. Data are available on reasonable request. Not applicable.

中文翻译：

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血清氨的使用：不必要、频繁且昂贵

背景/目的 虽然氨在肝性脑病 (HE) 的复杂病理生理学中发挥作用，但血清氨对于肝硬化患者的神经系统症状的诊断和相关性都不可靠。我们旨在量化中西部主要医疗保健系统中血清氨的订购、成本和适当使用。设计/方法 在 2015 年 1 月 1 日至 2019 年 12 月 31 日期间，评估了就诊于大型中西部卫生系统的成年患者的血清氨订购。结果血清氨订购很普遍，在 5 年内订购了 20338 项测试。随着时间的推移，每 100 000 例慢性肝病入院患者中不适当的血清氨检测数量没有差异（Pearson 相关系数=-0.24，p=0.70）。作为订购的总氨测试的比例，不适当的测试随着时间的推移而增加（皮尔逊相关系数=0.91，p=0.03）。与学术医疗中心相比，社区医院的不适当订购更为常见（99.3% vs 87.6%，p<0.001）。结论 尽管有证据表明血清氨水平对于 HE 的诊断不可靠，并且与肝硬化个体的 HE 严重程度无关，但订购仍然普遍存在，导致浪费和潜在危害。可根据合理要求提供数据。不适用。结论 尽管有证据表明血清氨水平对于 HE 的诊断不可靠，并且与肝硬化个体的 HE 严重程度无关，但订购仍然普遍存在，导致浪费和潜在危害。可根据合理要求提供数据。不适用。结论 尽管有证据表明血清氨水平对于 HE 的诊断不可靠，并且与肝硬化个体的 HE 严重程度无关，但订购仍然普遍存在，导致浪费和潜在危害。可根据合理要求提供数据。不适用。