Benioff Children's Hospital and the University of California San Francisco Medical School, San Francisco, CA.
Johns Hopkins Children's Center and Johns Hopkins School of Medicine, Baltimore, MD.
Pediatr Crit Care Med. 2019 Feb;20(2):136-142. doi: 10.1097/PCC.0000000000001776.
To develop a postoperative mortality case-mix adjustment model to facilitate assessment of cardiac ICU quality of care, and to describe variation in adjusted cardiac ICU mortality across hospitals within the Pediatric Cardiac Critical Care Consortium.
Observational analysis.
Multicenter Pediatric Cardiac Critical Care Consortium clinical registry.
All surgical cardiac ICU admissions between August 2014 and May 2016. The analysis included 8,543 admissions from 23 dedicated cardiac ICUs.
None.
We developed a novel case-mix adjustment model to measure postoperative cardiac ICU mortality after congenital heart surgery. Multivariable logistic regression was performed to assess preoperative, intraoperative, and immediate postoperative severity of illness variables as candidate predictors. We used generalized estimating equations to account for clustering of patients within hospital and obtain robust SEs. Bootstrap resampling (1,000 samples) was used to derive bias-corrected 95% CIs around each predictor and validate the model. The final model was used to calculate expected mortality at each hospital. We calculated a standardized mortality ratio (observed-to-expected mortality) for each hospital and derived 95% CIs around the standardized mortality ratio estimate. Hospital standardized mortality ratio was considered a statistically significant outlier if the 95% CI did not include 1. Significant preoperative predictors of mortality in the final model included age, chromosomal abnormality/syndrome, previous cardiac surgeries, preoperative mechanical ventilation, and surgical complexity. Significant early postoperative risk factors included open sternum, mechanical ventilation, maximum vasoactive inotropic score, and extracorporeal membrane oxygenation. The model demonstrated excellent discrimination (C statistic, 0.92) and adequate calibration. Comparison across Pediatric Cardiac Critical Care Consortium hospitals revealed five-fold difference in standardized mortality ratio (0.4-1.9). Two hospitals had significantly better-than-expected and two had significantly worse-than-expected mortality.
For the first time, we have demonstrated that variation in mortality as a quality metric exists across dedicated cardiac ICUs. These findings can guide efforts to reduce mortality after cardiac surgery.
开发一种术后死亡率病例组合调整模型，以促进评估心脏 ICU 的护理质量，并描述儿科心脏危重病护理联合会内各医院之间调整后心脏 ICU 死亡率的差异。
观察性分析。
多中心儿科心脏危重病护理联合会临床登记处。
2014 年 8 月至 2016 年 5 月期间所有外科心脏 ICU 入院患者。该分析包括 23 个专用心脏 ICU 的 8543 例入院患者。
无。
我们开发了一种新的病例组合调整模型，用于测量先天性心脏病手术后的术后心脏 ICU 死亡率。多变量逻辑回归用于评估术前、术中以及即刻术后严重程度变量作为候选预测因素。我们使用广义估计方程来考虑患者在医院内的聚类，并获得稳健的 SE。使用自举重采样（1000 个样本）来围绕每个预测因素获得偏倚校正的 95%CI，并验证模型。使用最终模型计算每个医院的预期死亡率。我们计算了每个医院的标准化死亡率比（观察到的与预期死亡率），并获得了标准化死亡率比估计值的 95%CI。如果 95%CI 不包括 1，则认为医院的标准化死亡率比是统计学上的显著异常值。最终模型中死亡率的显著术前预测因素包括年龄、染色体异常/综合征、先前的心脏手术、术前机械通气以及手术复杂性。显著的早期术后危险因素包括开胸、机械通气、最大血管活性正性肌力评分和体外膜氧合。该模型显示出优异的区分能力（C 统计量，0.92）和足够的校准。儿科心脏危重病护理联合会内各医院之间的比较显示，标准化死亡率比存在五倍差异（0.4-1.9）。两所医院的死亡率明显好于预期，两所医院的死亡率明显差于预期。
我们首次证明，作为质量指标的死亡率差异确实存在于专用心脏 ICU 之间。这些发现可以指导努力降低心脏手术后的死亡率。
