BACKGROUND In hospitalized patients, QT/QTc (heart rate corrected) prolongation on the electrocardiogram (ECG) increases the risk of torsade de pointes. Manual measurements are time-consuming and often inaccurate. Some bedside monitors automatically and continuously measure QT/QTc; however, the agreement between computerized versus nurse-measured values has not been evaluated. OBJECTIVE The aim of this study was to examine the agreement between computerized QT/QTc and bedside and expert nurses who used electronic calipers. METHODS This was a prospective observational study in 3 intensive care units. Up to 2 QT/QTc measurements (milliseconds) per patient were collected. Bland-Altman test was used to analyze measurement agreement. RESULTS A total of 54 QT/QTc measurements from 34 patients admitted to the ICU were included. The mean difference (bias) for QT comparisons was as follows: computerized versus expert nurses, -11.04 ± 4.45 milliseconds (95% confidence interval [CI], -2.3 to -19.8; P = .016), and computerized versus bedside nurses, -13.72 ± 6.70 (95% CI, -0.70 to -26.8; P = .044). The mean bias for QTc comparisons was as follows: computerized versus expert nurses, -12.46 ± 5.80 (95% CI, -1.1 to -23.8; P = .035), and computerized versus bedside nurses, -18.49 ± 7.90 (95% CI, -3.0 to -33.9; P = .022). CONCLUSION Computerized QT/QTc measurements calculated by bedside monitor software and measurements performed by nurses were in close agreement; statistically significant differences were found, but differences were less than 20 milliseconds (on-half of a small box), indicating no clinical significance. Computerized measurements may be a suitable alternative to nurse-measured QT/QTc. This could reduce inaccuracies and nurse burden while increasing adherence to practice recommendations. Further research comparing computerized QT/QTc from bedside monitoring to standard 12-lead electrocardiogram in a larger sample, including non-ICU patients, is needed.

中文翻译：

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床边护士和专家护士使用电子卡尺进行计算机化 QT 和 QTc 间隔测量的一致性。

背景 在住院患者中，心电图 (ECG) 上的 QT/QTc（校正心率）延长会增加尖端扭转型室性心动过速的风险。手动测量非常耗时且常常不准确。一些床边监护仪自动连续测量 QT/QTc；然而，计算机测量值与护士测量值之间的一致性尚未得到评估。目的 本研究的目的是检验计算机化 QT/QTc 与使用电子卡尺的床边护士和专家护士之间的一致性。方法 这是在 3 个重症监护室进行的一项前瞻性观察研究。每个患者最多收集 2 个 QT/QTc 测量值（毫秒）。Bland-Altman 检验用于分析测量一致性。结果 共纳入 34 名 ICU 患者的 54 次 QT/QTc 测量结果。QT 比较的平均差异（偏差）如下：计算机护士与专家护士相比，-11.04 ± 4.45 毫秒（95% 置信区间 [CI]，-2.3 至 -19.8；P = .016），以及计算机护士与床边护士， -13.72 ± 6.70（95% CI，-0.70 至 -26.8；P = .044）。QTc 比较的平均偏倚如下：计算机化护士与专家护士相比，-12.46 ± 5.80（95% CI，-1.1 至 -23.8；P = .035），计算机化护士与床边护士相比，-18.49 ± 7.90（95% CI） ，-3.0 至 -33.9；P = .022)。结论 通过床边监测软件计算的计算机 QT/QTc 测量结果与护士执行的测量结果非常一致；发现了统计学上显着的差异，但差异小于 20 毫秒（小方框的一半），表明没有临床意义。计算机测量可能是护士测量的 QT/QTc 的合适替代方案。这可以减少不准确性和护士负担，同时提高对实践建议的遵守率。需要进一步研究在更大的样本（包括非 ICU 患者）中比较床边监测的计算机 QT/QTc 与标准 12 导联心电图。