Inefficiency as the major driver of excess costs in lung resection

Risk-adjusted outcomes of surgical care are important for quality and cost assessments. Although cardiac surgery is commonly studied, risk-adjusted analysis of excess costs of lung resection has not been pursued.

We used 2002 to 2005 National Inpatient Sample of the Healthcare Cost and Utilization Project data to evaluate adverse outcomes and costs in elective lung resections in hospitals with more than 20 cases during that period. Adverse outcomes were inpatient death or excessive risk-adjusted postoperative stay. Logistic models were defined to predict adverse outcomes. Linear models were designed to predict costs. Hospital-specific adverse outcome rates and costs were measured to define performance outliers. Cost-effective reference hospitals were used to define total excess costs.

Among 12,182 patients at 215 hospitals undergoing lung resection, there were 336 inpatient deaths (2.8%) and 880 live discharges with prolonged risk-adjusted postoperative stay (7.2%). Predictive models for mortality and risk-adjusted postoperative stay had C statistics of 0.773 and 0.643, respectively. There were 11 ineffective hospitals (5.1%) with excessive adverse outcomes (P < .005) and 34 inefficient hospitals (15.8%) meeting quality measures but with higher than predicted costs (P < .0005). Ineffective hospitals had costs $1020 per case lower than predicted. Inefficient hospitals had costs $9978 higher than predicted.

Inefficiency is the major factor in excess inpatient costs associated with lung resection in this model. Although refinements in databases, including total physician costs and postdischarge adverse event costs, will alter models, excess costs of lung resection appear to be driven by inefficiency, not adverse outcomes.