Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.
Vascular Surgery Research Group, Imperial College London, London, UK.
Br J Surg. 2018 Aug;105(9):1135-1144. doi: 10.1002/bjs.10820. Epub 2018 Apr 6.
The aim of this study was to develop a 48-h mortality risk score, which included morphology data, for patients with ruptured abdominal aortic aneurysm presenting to an emergency department, and to assess its predictive accuracy and clinical effectiveness in triaging patients to immediate aneurysm repair, transfer or palliative care.
Data from patients in the IMPROVE (Immediate Management of the Patient With Ruptured Aneurysm: Open Versus Endovascular Repair) randomized trial were used to develop the risk score. Variables considered included age, sex, haemodynamic markers and aortic morphology. Backwards selection was used to identify relevant predictors. Predictive performance was assessed using calibration plots and the C-statistic. Validation of the newly developed and other previously published scores was conducted in four external populations. The net benefit of treating patients based on a risk threshold compared with treating none was quantified.
Data from 536 patients in the IMPROVE trial were included. The final variables retained were age, sex, haemoglobin level, serum creatinine level, systolic BP, aortic neck length and angle, and acute myocardial ischaemia. The discrimination of the score for 48-h mortality in the IMPROVE data was reasonable (C-statistic 0·710, 95 per cent c.i. 0·659 to 0·760), but varied in external populations (from 0·652 to 0·761). The new score outperformed other published risk scores in some, but not all, populations. An 8 (95 per cent c.i. 5 to 11) per cent improvement in the C-statistic was estimated compared with using age alone.
The assessed risk scores did not have sufficient accuracy to enable potentially life-saving decisions to be made regarding intervention. Focus should therefore shift to offering repair to more patients and reducing non-intervention rates, while respecting the wishes of the patient and family.
本研究旨在开发一种 48 小时死亡率风险评分，该评分纳入形态学数据，用于就诊于急诊科的破裂腹主动脉瘤患者，并评估其在分诊患者行即刻腹主动脉瘤修复、转科或姑息治疗方面的预测准确性和临床效果。
本研究使用 IMPROVE（破裂型腹主动脉瘤患者即刻处理：开放与腔内修复）随机试验患者的数据来开发风险评分。考虑的变量包括年龄、性别、血流动力学标志物和主动脉形态。采用向后选择法来确定相关预测因素。使用校准图和 C 统计量评估预测性能。在四个外部人群中对新开发的评分和其他先前发表的评分进行验证。基于风险阈值治疗患者与不治疗任何患者相比的净获益情况进行了量化。
纳入 IMPROVE 试验中的 536 例患者的数据。最终保留的变量为年龄、性别、血红蛋白水平、血清肌酐水平、收缩压、主动脉颈长度和角度以及急性心肌缺血。该评分对 48 小时死亡率的区分度在 IMPROVE 数据中尚可（C 统计量 0·710，95%可信区间 0·659 至 0·760），但在外部人群中有所不同（0·652 至 0·761）。在某些但不是所有人群中，新评分均优于其他已发表的风险评分。与仅使用年龄相比，估计 C 统计量提高了 8（95%可信区间 5 至 11）个百分点。
评估的风险评分没有足够的准确性来对干预决策进行潜在的挽救生命的判断。因此，重点应转移到为更多患者提供修复治疗，并降低非干预率，同时尊重患者和家属的意愿。
