Roger J. Meimban

Patient Characteristics and the Occurrence of Never Events

OBJECTIVEnTo determine whether the occurrence of never events after major surgical procedures is affected by patient and disease characteristics and by the type of operation performed.nnnDESIGNnEpidemiological analysis.nnnINTERVENTIONSnDerivation and assessment of predictive equations for postoperative infectious events and decubitus ulcers using Healthcare Cost and Utilization Project Nationwide Inpatient Sample administrative claims data for patients hospitalized between 2002 and 2005.nnnMAIN OUTCOME MEASURESnC statistics for each predictive equation with and without hospital dummy variables.nnnRESULTSnPredictive equations for 6 of 8 complications had C statistics greater than 0.65 without hospital variables, while 2 had C statistics of less than 0.55. All equations had C statistics greater than 0.75 when hospital dummy variables were included.nnnCONCLUSIONSnPatient characteristics and type of operative procedure are important predictors of complications of surgical care evaluated in this study, undermining the rationale for their current classification as never events. Variations in risk-adjusted complication rates among hospitals support the influence of quality of care on their occurrence. Development and use of warranties to cover costs associated with caring for the unavoidable components of potentially avoidable complications is proposed as a means of rewarding high-quality providers without creating unrealistic expectations or perverse financial incentives.

Combining administrative and clinical data to stratify surgical risk.

Objective:To evaluate whether administrative claims data (ADM) from hospital discharges can be transformed by present-on-admission (POA) codes and readily available clinical data into a refined database that can support valid risk stratification (RS) of surgical outcomes. Summary Background Data:ADM from hospital discharges have been used for RS of medical and surgical outcomes, but results generally have been viewed with skepticism because of limited clinical information and questionable predictive accuracy. Methods:We used logistic regression analysis to choose predictor variables for RS of mortality in abdominal aortic aneurysm repair, coronary artery bypass graft surgery, and craniotomy, and for RS of 4 postoperative complications (ie, physiologic/metabolic derangement, respiratory failure, pulmonary embolism/deep vein thrombosis, and sepsis) after selected operations. RS models were developed for age only (Age model), ADM only (ADM model), ADM enhanced with POA codes for secondary diagnoses (POA-ADM model), POA-ADM supplemented with admission laboratory data (Laboratory model), Laboratory model supplemented with admission vital signs and additional laboratory data (VS model), VS model supplemented with key clinical findings abstracted from medical records (KCF model), and KCF model supplemented with composite clinical scores (Full model). Models were evaluated using c-statistics, case-based errors in predictions, and measures of hospital-based systematic bias. Results:The addition of POA codes and numerical laboratory results to ADM was associated with substantial improvements in all measures of analytic performance. In contrast, the addition of difficult-to-obtain key clinical findings resulted in only small improvements in predictions. Conclusions:Enhancement of ADM with POA codes and readily available laboratory data can efficiently support accurate risk-stratified measurements of clinical outcomes in surgical patients.

Adverse outcomes in surgery: redefinition of postoperative complications

BACKGROUNDnWe propose that excess risk-adjusted, postoperative length of stay (poLOS) is a valid indicator of an adverse outcome.nnnMETHODSnHospital administrative claims data for elective colon resection, coronary bypass graft surgery, and total hip replacement were used from the 100 largest-volume hospitals in the Health Care Cost and Utilization Project for 2005. Risk-adjusted poLOS linear models were designed and outliers were determined using control charts. Costs of hospital care were examined by the presence of coded complications (CCs) and/or being a poLOS outlier.nnnRESULTSnPatterns of CCs and risk-adjusted poLOS outliers were significantly different (P < .0001, chi-square test). For all procedures, costs of care were similar with or without CCs if the patients were not poLOS outliers. For patients who were poLOS outliers, costs were significantly different (Tukey-Kramer test) independent of whether CCs were present or not.nnnCONCLUSIONSnAdverse surgical outcomes are better defined by risk-adjusted poLOS and cost criteria rather than coded or surveillance observations.

The Impact of Ineffective and Inefficient Care on the Excess Costs of Elective Surgical Procedures

BACKGROUNDnIneffective and inefficient elective surgical care has been identified as a major factor accounting for excessive costs of elective surgical procedures. The identification of cost-effective hospitals permits objective measurement of excessive surgical costs and development of strategies to improve outcomes and efficiency.nnnSTUDY DESIGNnWe used the 2002 to 2005 National Inpatient Sample from the Healthcare Cost and Utilization Project for colorectal resections, elective coronary bypass grafts, total hip replacement, and hysterectomy to assess hospitals risk-adjusted adverse outcome rates and costs. Adverse outcomes were defined as inpatient deaths or prolonged risk-adjusted postoperative lengths of stay (RApoLOS). Risk-adjusted costs were determined for all patients, using hospital-specific cost-to-charge ratios to convert charges to costs. Effective, efficient hospitals were identified to serve as a reference standard. Outlier hospitals for ineffectiveness (p < 0.005) and inefficiency (p < 0.0005) were analyzed to measure excessive costs relative to reference hospitals.nnnRESULTSnHospital costs for the 4 operations combined were

Surgical Warranties to Improve Quality and Efficiency in Elective Colon Surgery

325 million greater (8%) than predicted based on the reference standard. A total of 95% of excessive costs were due to inefficiency and only 5% were due to higher-than-predicted adverse outcomes rates. Elimination of predicted excess costs of all adverse outcomes for all 4 procedures at all hospitals studied would result in smaller savings than elimination of inefficiency-associated costs at inefficient hospitals alone.nnnCONCLUSIONSnInefficiency is substantially more important than suboptimal outcomes in accounting for the excessive hospital costs of elective surgical care in this study population.

Control charts to identify adverse outcomes in elective colon resection

BACKGROUNDnUncomplicated surgical care has highly variable costs. High costs of complications have led payers to deny additional payments even for predictable complications.nnnHYPOTHESISnA payment warranty indexed to effective and efficient hospitals can promote quality and economic stewardship in surgical care.nnnDESIGNnAnalysis of hospital costs for elective colon surgery in the Healthcare Cost and Utilization Projects National Inpatient Sample from 2002 through 2005.nnnSETTINGnA 20% sample of acute care hospitals in the United States.nnnPATIENTS AND METHODSnData for elective colon resections were used to create predictive models for adverse outcomes (AOs) and costs. Total hospital costs were determined using cost-to-charge ratios. Costs of AOs were computed as total costs minus predicted costs of uncomplicated care. Surgical warranties were computed as the probability of AOs times per-case predicted costs of AOs. Final predictive models were calibrated using data only from effective and efficient hospitals.nnnRESULTSnWe studied 51 602 cases from 632 hospitals. There were 4048 (7.8%) AOs with 505 deaths (1.0%); 19 hospitals had excessive AOs and 95 hospitals had excessive costs. For 518 effective and efficient hospitals, total per-case costs for routine care were

Modifying ICD-9-CM Coding of Secondary Diagnoses to Improve Risk-Adjustment of Inpatient Mortality Rates

9843 with an average warranty of

Controlling costs without compromising quality: paying hospitals for total knee replacement.

1294 and a

Comparative effectiveness and efficiency in peripheral vascular surgery.

276 stop-loss allocation. This cost model would reduce national expenditures for colon surgery by 6%.nnnCONCLUSIONSnComplications and costs of care can be indexed to quality performing hospitals. Warranties for surgical care can reward effective and efficient care and preclude the need for additional payments for complications.

Inefficiency as the major driver of excess costs in lung resection

BACKGROUNDnControl charts have been proposed for the measurement of quality in surgical care.nnnMETHODSnFor each of 181 study hospitals in the 2005 National Inpatient Sample of the Healthcare Cost and Utilization Project database, an average moving range control chart for risk-adjusted postoperative length of stay (RApoLOS) was created for patients discharged alive after elective colectomy. RApoLOS outliers using upper control limits of 2.0σ, 2.5σ, and 3.0σ were correlated to coded complications (CCs). Hospital costs were correlated to RApoLOS outliers and CCs.nnnRESULTSnOf 13,118 live discharges, 902 (6.9%) were outliers using a 3.0σ upper control limit, 1,350 (10.3%) were 2.5σ outliers, and 2,053 (15.7%) were 2.0σ outliers. CCs were identified in 92.7% of 3.0σ outliers, in 81.3% of 2.5σ outliers, and 70.6% of 2.0σ outliers. Increased costs were associated with RApoLOS outliers and poorly with CCs.nnnCONCLUSIONSnAverage moving range control charts for RApoLOS outliers are valid tools for measurement of surgical quality and costs.