Wells P S, Ginsberg J S, Anderson D R, Kearon C, Gent M, Turpie A G, Bormanis J, Weitz J, Chamberlain M, Bowie D, Barnes D, Hirsh J
University of Ottawa, Ontario, Canada.
Ann Intern Med. 1998 Dec 15;129(12):997-1005. doi: 10.7326/0003-4819-129-12-199812150-00002.
The low specificity of ventilation-perfusion lung scanning complicates the management of patients with suspected pulmonary embolism.
To determine the safety of a clinical model for patients with suspected pulmonary embolism.
Prospective cohort study.
Five tertiary care hospitals.
1239 inpatients and outpatients with suspected pulmonary embolism.
A clinical model categorized pretest probability of pulmonary embolism as low, moderate, or high, and ventilation-perfusion scanning and bilateral deep venous ultrasonography were done. Testing by serial ultrasonography, venography, or angiography depended on pretest probability and lung scans.
Patients were considered positive for pulmonary embolism if they had an abnormal pulmonary angiogram, abnormal ultrasonogram or venogram, high-probability ventilation-perfusion scan plus moderate or high pretest probability, or venous thromboembolic event during the 3-month follow-up. All other patients were considered negative for pulmonary embolism. Rates of pulmonary embolism during follow-up in patients who had a normal lung scan and those with a non-high-probability scan and normal serial ultrasonogram were compared.
Pretest probability was low in 734 patients (3.4% with pulmonary embolism), moderate in 403 (27.8% with pulmonary embolism), and high in 102 (78.4% with pulmonary embolism). Three of the 665 patients (0.5% [95% CI, 0.1% to 1.3%]) with low or moderate pretest probability and a non-high-probability scan who were considered negative for pulmonary embolism had pulmonary embolism or deep venous thrombosis during 90-day follow-up; this rate did not differ from that in patients with a normal scan (0.6% [CI, 0.1% to 1.8%]; P > 0.2).
Management of patients with suspected pulmonary embolism on the basis of pretest probability and results of ventilation-perfusion scanning is safe.
通气-灌注肺扫描的低特异性使疑似肺栓塞患者的管理变得复杂。
确定一种针对疑似肺栓塞患者的临床模型的安全性。
前瞻性队列研究。
五家三级医疗医院。
1239例疑似肺栓塞的住院和门诊患者。
一种临床模型将肺栓塞的预测试概率分为低、中、高，然后进行通气-灌注扫描和双侧深静脉超声检查。根据预测试概率和肺部扫描结果决定是否进行系列超声检查、静脉造影或血管造影。
如果患者的肺血管造影异常、超声检查或静脉造影异常、通气-灌注扫描为高概率且预测试概率为中或高，或者在3个月随访期间发生静脉血栓栓塞事件，则被视为肺栓塞阳性。所有其他患者被视为肺栓塞阴性。比较肺部扫描正常的患者以及扫描非高概率且系列超声检查正常的患者在随访期间的肺栓塞发生率。
734例患者的预测试概率低（肺栓塞发生率为3.4%），403例患者的预测试概率中等（肺栓塞发生率为27.8%），102例患者的预测试概率高（肺栓塞发生率为78.4%）。665例预测试概率低或中等且扫描非高概率、被视为肺栓塞阴性的患者中，有3例（0.5%[95%CI，0.1%至1.3%]）在90天随访期间发生了肺栓塞或深静脉血栓形成；该发生率与肺部扫描正常的患者（0.6%[CI，0.1%至1.8%]；P>0.2）无差异。
基于预测试概率和通气-灌注扫描结果对疑似肺栓塞患者进行管理是安全的。
