BACKGROUND Chest pain is the second most common chief complaint in North American emergency departments. Data from the U.S. suggest that 2.1% of patients with acute myocardial infarction and 2.3% of patients with unstable angina are misdiagnosed, with slightly higher rates reported in a recent Canadian study (4.6% and 6.4%, respectively). Information obtained from the history, 12-lead ECG, and a single set of cardiac enzymes is unable to identify patients who are safe for early discharge with sufficient sensitivity. The 2007 ACC/AHA guidelines for UA/NSTEMI do not identify patients at low risk for adverse cardiac events who can be safely discharged without provocative testing. As a result large numbers of low risk patients are triaged to chest pain observation units and undergo provocative testing, at significant cost to the healthcare system. Clinical decision rules use clinical findings (history, physical exam, test results) to suggest a diagnostic or therapeutic course of action. Currently no methodologically robust clinical decision rule identifies patients safe for early discharge. METHODS/DESIGN The goal of this study is to derive a clinical decision rule which will allow emergency physicians to accurately identify patients with chest pain who are safe for early discharge. The study will utilize a prospective cohort design. Standardized clinical variables will be collected on all patients at least 25 years of age complaining of chest pain prior to provocative testing. Variables strongly associated with the composite outcome acute myocardial infarction, revascularization, or death will be further analyzed with multivariable analysis to derive the clinical rule. Specific aims are to: i) apply standardized clinical assessments to patients with chest pain, incorporating results of early cardiac testing; ii) determine the inter-observer reliability of the clinical information; iii) determine the statistical association between the clinical findings and the composite outcome; and iv) use multivariable analysis to derive a highly sensitive clinical decision rule to guide triage decisions. DISCUSSION The study will derive a highly sensitive clinical decision rule to identify low risk patients safe for early discharge. This will improve patient care, lower healthcare costs, and enhance flow in our busy and overcrowded emergency departments.

中文翻译：

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一项为急诊室胸痛患者分诊得出临床决策规则的研究：设计和方法。


背景胸痛是北美急诊科第二常见的主诉。美国的数据表明，2.1% 的急性心肌梗死患者和 2.3% 的不稳定心绞痛患者被误诊，加拿大最近的一项研究报告的误诊率略高（分别为 4.6% 和 6.4%）。从病史、12 导联心电图和一组心肌酶中获得的信息无法以足够的敏感性识别可以安全提早出院的患者。 2007 年 ACC/AHA UA/NSTEMI 指南并未识别出发生不良心脏事件的低风险患者，这些患者无需进行激发试验即可安全出院。结果，大量低风险患者被分流到胸痛观察单位并接受刺激性检测，这给医疗保健系统带来了巨大成本。临床决策规则使用临床发现（病史、体格检查、测试结果）来建议诊断或治疗方案。目前，尚无方法论上稳健的临床决策规则可以确定患者可以安全提前出院。方法/设计本研究的目的是得出临床决策规则，使急诊医生能够准确识别可以安全早期出院的胸痛患者。该研究将采用前瞻性队列设计。在激发测试之前，将收集所有年龄至少 25 岁且主诉胸痛的患者的标准化临床变量。将通过多变量分析进一步分析与急性心肌梗死、血运重建或死亡等复合结果密切相关的变量，以得出临床规则。 具体目标是： i) 对胸痛患者应用标准化临床评估，纳入早期心脏检查的结果； ii) 确定临床信息的观察者间可靠性； iii) 确定临床结果与综合结果之间的统计关联； iv) 使用多变量分析得出高度敏感的临床决策规则来指导分诊决策。讨论 该研究将得出高度敏感的临床决策规则，以确定可以安全提前出院的低风险患者。这将改善患者护理，降低医疗成本，并提高我们繁忙且拥挤的急诊科的流量。