Background

The role of specific scoring systems in predicting risk of surgical site infections (SSIs) after coronary artery bypass grafting (CABG) has not been established.

Aim

To validate the most relevant predictive systems for SSIs after CABG.

Methods

Five predictive systems (eight models) for SSIs after CABG were evaluated retrospectively in 7090 consecutive patients undergoing isolated (73.9%) or combined (26.1%) CABG. For each model, accuracy of prediction, calibration, and predictive power were assessed with area under receiver–operating characteristic curve (aROC), the Hosmer–Lemeshow test, and the Goodman–Kruskal γ-coefficient, respectively. Six predictive scoring systems for 30-day in-hospital mortality after cardiac operations were evaluated as to prediction of SSIs. The models were compared one-to-one using the Hanley–McNeil method.

Findings

There were 724 (10.2%) SSIs. Whereas all models showed satisfactory calibration (P = 0.176–0.656), accuracy of prediction was low (aROC: 0.609–0.650). Predictive power was moderate (γ: 0.315–0.386) for every model but one (γ: 0.272). When compared one-to-one, the Northern New England Cardiovascular Disease Study Group mediastinitis score had a higher discriminatory power both in overall series (aROC: 0.634) and combined CABG patients (aROC: 0.648); in isolated CABG patients, both models of the Fowler score showed a higher discriminatory power (aROC: 0.651 and 0.660). Accuracy of prediction for SSIs was low (aROC: 0.564–0.636) even for six scoring systems devised to predict mortality after cardiac surgery.

Conclusion

In this validation study, current predictive models for SSIs after CABG showed low accuracy of prediction despite satisfactory calibration and moderate predictive power.

中文翻译：

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冠状动脉手术后手术部位感染的预测模型：对7090名连续患者进行的验证研究的真知灼见

背景

尚未建立特定评分系统在预测冠状动脉搭桥术（CABG）后手术部位感染（SSI）风险中的作用。

目的

验证CABG之后最相关的SSI预测系统。

方法

回顾性分析了7090例接受孤立CABG（73.9％）或联合CABG（26.1％）的连续患者的5种CABG后SSI预测系统（八个模型）。对于每种模型，分别通过接收器工作特征曲线（aROC），Hosmer-Lemeshow检验和Goodman-Kruskalγ系数下的面积评估预测，校准和预测能力的准确性。评估了六个心脏手术后30天住院死亡率的预测评分系统，以评估SSI。使用Hanley-McNeil方法一对一比较模型。

发现

有724个（10.2％）SSI。尽管所有模型的校准结果均令人满意（P  = 0.176-0.656），但预测的准确性却很低（aROC：0.609-0.650）。每个模型的预测能力都中等（γ：0.315–0.386），但一个模型（γ：0.272）。当进行一对一比较时，新英格兰北部心血管疾病研究组纵隔炎评分在整个系列（aROC：0.634）和合并CABG患者（aROC：0.648）中均具有较高的鉴别力。在孤立的CABG患者中，两种Fowler评分模型均显示出较高的辨别力（aROC：0.651和0.660）。即使采用六个计分系统来预测心脏手术后的死亡率，SSI的预测准确性也很低（aROC：0.564–0.636）。

结论

在这项验证研究中，尽管CABG令人满意的校准和适度的预测能力，但CABG后目前针对SSI的预测模型显示出较低的预测准确性。