Cohen Mark E, Bilimoria Karl Y, Ko Clifford Y, Richards Karen, Hall Bruce Lee
American College of Surgeons, 633 N. Saint Clair Street, Chicago, IL, USA.
Ann Surg. 2009 Apr;249(4):682-9. doi: 10.1097/SLA.0b013e31819eda21.
To examine the influence of American Society of Anesthesiologists Physical Status Classification (ASA) and preoperative Functional Health Status (FHS) variables on risk-adjusted estimates of surgical quality and to assess whether classifications are inflated at some hospitals.
ASA and FHS are influential in risk-adjusted comparisons of surgical quality. However, because ASA and FHS are subjective they can be inflated, making patients appear more ill than they actually are, and crediting hospitals for a sicker patient population.
We identified 28,751 colorectal surgery patients at 170 hospitals participating in the American College of Surgeon's National Surgical Quality Improvement Program (ACS NSQIP) during 2006 to 2007. Logistic regression models were developed for morbidity and mortality with and without inclusion of ASA and FHS. Hospital quality rankings from the different models were compared.
Morbidity and mortality rates were 24.3% and 3.9%, respectively. Percents of patients in ASA classes I through V were 3.3%, 46.4%, 41.5%,8.3%, and 0.7% and that were independent or partially or totally dependent were 89.2%, 7.2%, and 3.6%, respectively. Models that included ASA and FHS exhibited slightly better fit (Hosmer-Lemshow statistic) and discrimination(c-statistic) than models without both these variables, though magnitudes of differences were consistent with chance. There was inconsistent evidence for improper assignment of ASA and FHS.
The small improvements in model quality when both ASA and FHS are present versus absent, suggest that they make a unique contribution to assessing severity of preoperative risk. With little indication that these subjective variables are subject to an important level of institutional bias, it is appropriate that they be used to assess risk-adjusted surgical quality. Periodic monitoring for inappropriate inflation of ASA status is warranted.
研究美国麻醉医师协会身体状况分类（ASA）和术前功能健康状况（FHS）变量对手术质量风险调整估计值的影响，并评估某些医院的分类是否存在夸大情况。
ASA和FHS在手术质量的风险调整比较中具有影响力。然而，由于ASA和FHS是主观的，它们可能被夸大，使患者看起来比实际病情更严重，并将病情较重的患者群体的功劳归于医院。
我们确定了2006年至2007年期间参与美国外科医师学会国家外科质量改进计划（ACS NSQIP）的170家医院的28751例结直肠手术患者。建立了包含和不包含ASA和FHS的发病率和死亡率的逻辑回归模型。比较了不同模型的医院质量排名。
发病率和死亡率分别为24.3%和3.9%。ASA分级I至V级的患者百分比分别为3.3%、46.4%、41.5%、8.3%和0.7%，独立或部分或完全依赖的患者百分比分别为89.2%、7.2%和3.6%。包含ASA和FHS的模型比不包含这两个变量的模型表现出略好的拟合度（Hosmer-Lemshow统计量）和区分度（c统计量），尽管差异幅度与随机情况一致。关于ASA和FHS分配不当的证据并不一致。
同时存在ASA和FHS与不存在时模型质量的微小改善表明，它们在评估术前风险严重程度方面做出了独特贡献。几乎没有迹象表明这些主观变量存在重要程度的机构偏差，因此使用它们来评估风险调整后的手术质量是合适的。有必要定期监测ASA状态是否被不恰当地夸大。
