Kay G L, Sun G W, Aoki A, Prejean C A
Heart Institute, Good Samaritan Hospital, Los Angeles, California 90017-2395, USA.
Ann Thorac Surg. 1995 Dec;60(6):1640-50; discussion 1651. doi: 10.1016/0003-4975(95)00894-2.
Preoperative ejection fraction (EF) has been shown to adversely affect postoperative hospital mortality and morbidity for patients undergoing isolated coronary artery bypass grafting.
To investigate influence of EF on isolated coronary artery bypass grafting outcomes (overall hospital mortality, hospital cardiac mortality, hospital morbidity, and hospital costs), data were reviewed from 1,354 consecutive patients who underwent isolated coronary artery bypass grafting between January 1, 1990, and April 30, 1992, at a single nonprofit hospital. Overall hospital mortality was 4.06% (cardiac, 2.36%). Hospital morbidity was 14.25% (including mortality). Hospital costs (not charges) averaged $16,673 per patient. To explore the impact of preoperative EF, EF was stratified into regular intervals. Each interval was then compared with regard to hospital mortality, morbidity, and average costs. A new statistical tool, discharge analysis, was developed to analyze the cost data. This was necessary because previous efforts at cost analysis have used tools inappropriate for real world cost data.
The statistical analysis showed that patients with EF of 0.40 or greater had the best outcomes (lowest mortality, morbidity, and cost). Once the EF is 0.40 or greater the EF does not carry further predictive value. At EF less than 0.40, patients with EF less than 0.30 have a poorer outcome than patients with EF of 0.30 to 0.39.
(1) Ejection fraction is a valid predictor of mortality, morbidity and resource utilization based on statistical analysis. (2) Patients can be broadly grouped as having EF greater than 0.40, less than 0.30, or from 0.30 to 0.39 with regard to clinical and cost outcomes. (3) Postoperative length of stay is not predicted by risk-adjusted EF. (4) A new tool, discharge analysis, is presented to facilitate cost analysis.
术前射血分数（EF）已被证明会对接受单纯冠状动脉旁路移植术的患者术后医院死亡率和发病率产生不利影响。
为研究EF对单纯冠状动脉旁路移植术结局（总体医院死亡率、医院心脏死亡率、医院发病率和医院成本）的影响，回顾了1990年1月1日至1992年4月30日期间在一家非营利性医院连续接受单纯冠状动脉旁路移植术的1354例患者的数据。总体医院死亡率为4.06%（心脏相关死亡率为2.36%）。医院发病率为14.25%（包括死亡率）。每位患者的医院成本（非收费）平均为16,673美元。为探究术前EF的影响，将EF按固定间隔分层。然后比较每个间隔的医院死亡率、发病率和平均成本。开发了一种新的统计工具——出院分析，用于分析成本数据。这是必要的，因为之前的成本分析努力使用的工具不适用于实际的成本数据。
统计分析表明，EF为0.40或更高的患者结局最佳（死亡率、发病率和成本最低）。一旦EF为0.40或更高，EF就不再具有进一步的预测价值。在EF小于0.40时，EF小于0.30的患者结局比EF为0.30至0.39的患者更差。
（1）基于统计分析，射血分数是死亡率、发病率和资源利用的有效预测指标。（2）就临床和成本结局而言，患者可大致分为EF大于0.40、小于0.30或在0.30至0.39之间。（3）风险调整后的EF不能预测术后住院时间。（4）提出了一种新工具——出院分析，以促进成本分析。
