A longitudinal analysis of the relationship between in-hospital mortality in New York State and the volume of abdominal aortic aneurysm surgeries performed.

This study uses New York State hospital discharge data to examine the relationship between in-hospital mortality for a patient receiving an abdominal aortic aneurysm resection and the volume of aneurysm operations performed in the previous year at the hospital where the operation took place and by the surgeon performing the operation. Previous research on this topic is extended in several respects: (1) A three-year data base is used to examine the manner in which hospital and surgeon volume jointly affect mortality rate and to examine ruptured and unruptured aneurysms separately; (2) a six-year data base is used to study the "practice makes perfect" hypothesis and the "selective referral" hypothesis; and (3) the degree of specialization of high-volume surgeons is contrasted with that of other surgeons. The results demonstrate a significant inverse relationship between hospital volume and mortality rate for unruptured aneurysms. Further, very few surgeons substantially increased their aneurysm surgery volumes in the six-year study period. Weak selective referral effects were found for both surgeons and hospitals, and higher-volume aneurysm surgeons tended to have much higher specialization rates.

Management of depressed skull fracture in the newborn.

The authors describe 3 cases of neonatal depressed skull fracture subsequent to difficult delivery, treated without surgical elevation. None of the patients developed neurological deficits, cosmetic deformity or electroencephalographic signs of epileptiform activity. Neonatal depressed skull fractures not associated with focal neurological signs may not require surgical therapy; we are not certain what the absolute criteria for operation should be.

Community access and satisfaction: racial differences in later life.

Community access can be expected to have an important influence on the life satisfaction of the aged because of age-linked restrictions in social life space. Such access may be less important for older blacks, however, as a consequence of lifelong "ghettoization". These hypotheses are tested using national survey data. Community mobility is found to have a stronger association with life satisfaction for older whites, while having only an indirect effect through social interaction for older blacks. Directions for future research are suggested.

Clinical versus administrative data bases for CABG surgery. Does it matter?

This study compared the ability of a clinical and administrative data base in New York State to predict in-hospital mortality and to assess hospital performance for coronary artery bypass graft surgery. The results indicated that the clinical data base, the Cardiac Surgery Reporting System, is substantially better at predicting case-specific mortality than the administrative data base, the Statewide Planning and Research Cooperative System. Also, correlations between hospital mortality rates that are risk-adjusted using the two systems were only moderately high (0.75 to 0.80). The addition of new risk factors from the Statewide Planning and Research Cooperative System improved the predictive power of both systems but did not diminish the difference in effectiveness of the two systems. The three unique clinical risk factors in the Cardiac Surgery Reporting System (ejection fraction, reoperation, and more than 90% narrowing of the left main trunk) seemed to account for much of the difference in effectiveness of the two systems.

The decline in coronary artery bypass graft surgery mortality in New York State. The role of surgeon volume.

OBJECTIVE: To examine the longitudinal relationship between surgeon volume and in-hospital mortality for coronary artery bypass graft (CABG) surgery in New York State and to explain changes in mortality that occurred over time. DESIGN: Observation of clinically risk-adjusted operative mortality over time. SETTING: All 30 New York State hospitals in which CABG surgery was performed for 1989 through 1992. PATIENTS: All 57,187 patients undergoing isolated CABG surgery in New York State in 1989 through 1992 in the 30 hospitals. MAIN OUTCOME MEASURES: Actual, expected, and risk-adjusted mortality. RESULTS: Risk-adjusted in-hospital mortality decreased for all categories of surgeons. Low-volume surgeons (< or = 50 operations per year) experienced a 60% reduction in risk-adjusted mortality in the 4-year period, whereas the highest-volume surgeons (> 150 operations per year) experienced a 34% reduction. The percentage of patients undergoing CABG surgery by low-volume surgeons decreased from 7.6% in 1989 to 5.7% in 1992, a 25% decrease. CONCLUSIONS: The overall decline in risk-adjusted mortality could not be explained by shifts in patients away from low-volume surgeons to high-volume surgeons. The proportionately larger decrease in risk-adjusted mortality for low-volume surgeons could not be explained by changes in patient case mix or by improvements in the performance of surgeons with persistently low volumes. Part of the decrease was a result of the exodus of low-volume surgeons with high risk-adjusted mortality (in all years studied), the markedly better performance of surgeons who were new to the system (especially in 1991 and 1992), and the performance of surgeons who were not consistently low-volume surgeons (especially in 1992).

Interracial access to selected cardiac procedures for patients hospitalized with coronary artery disease in New York State.

This study examines black/white differences in the utilization of three cardiac procedures (coronary angiography, coronary artery bypass graft, and coronary angioplasty) for patients hospitalized with coronary artery disease in New York State in the first 6 months of 1987. In contrast with previous studies, disease stages are used to control for severity of illness in addition to various severity proxies. Another methodological difference is that patient episodes (a fixed period of time after an initial hospital admission) are used as the unit of analysis rather than discharges to accurately account for patients whose initial visit is to a hospital not certified to perform the procedure. After controlling for severity using logistic regression analysis, whites were found to undergo significantly more of each of the procedures than blacks (odds ratios of 1.25, 2.06, and 1.69 for angiography, bypass graft, and angioplasty, respectively). These significant differences existed for most levels of the various control variables.

Improving the outcomes of coronary artery bypass surgery in New York State.

OBJECTIVE: To assess changes in outcomes of coronary artery bypass graft (CABG) surgery in New York since 1989, when the State Department of Health began collecting, analyzing, and disseminating information regarding risk factors, mortality, and complications of CABG surgery. These new data stimulated specific quality improvement activities at hospitals throughout the state. DESIGN: A clinical database was used to identify significant independent risk factors and to assess risk-adjusted provider mortality rates. SETTING: All 30 hospitals performing CABG surgery in New York during the period 1989 through 1992. PATIENTS: All 57,187 patients undergoing isolated CABG surgery who were discharged from New York State hospitals in 1989 through 1992. MAIN OUTCOME MEASURES: Actual, expected (from a logistic regression model), and risk-adjusted in-hospital mortality. RESULTS: Actual mortality decreased from 3.52% in 1989 to 2.78% in 1992. Because average patient severity of illness increased, risk-adjusted mortality decreased even more--a decrease of 41% from 4.17% in 1989 to 2.45% in 1992. The risk-adjustment model performed well; there were no clinically or statistically significant differences between actual and predicted numbers of deaths at any of 10 levels of patient severity. CONCLUSIONS: We believe that this quality improvement program, based on the collection and dissemination of risk-adjusted mortality data for CABG surgery, played a significant role in the observed decline in the death rate from this procedure. Quality improvement programs based on similar principles for other procedures and conditions should be undertaken.

Relation of perioperative deaths to hospital volume among patients undergoing pancreatic resection for malignancy.

OBJECTIVE: The authors examined the effect of hospital and surgeon volume on perioperative mortality rates after pancreatic resection for the treatment of pancreatic cancer. METHODS: Discharge abstracts from 1972 patients who had undergone pancreaticoduodenectomy or total pancreatectomy for malignancy in New York State between 1984 and 1991 were obtained from the Statewide Planning and Research Cooperative System. Logistic regression analysis was used to determine the relationship between hospital and surgeon experience to perioperative outcome. RESULTS: More than 75% of patients underwent resection at minimal-volume (fewer than 10 cases) or low-volume (10-50 cases) centers (defined as hospitals in which a minimal number of resections were performed in a given year), and these hospitals represented 98% of the institutions treating peripancreatic cancer. The two high-volume hospitals (more than 81 cases) demonstrated a significantly lower perioperative mortality rate (4.0%) compared with the minimal- (21.8%) and low-volume (12.3%) hospitals (p < 0.001). The perioperative mortality rate was 15.5% for low-volume (fewer than 9 cases) surgeons (defined as surgeons who had performed a minimal number of resections in any hospital in a given year) (n = 687) compared with 4.7% for high-volume (more than 41 cases) pancreatic surgeons (n = 4) (p < 0.001). Logistic regression analysis demonstrated that perioperative death is significantly (p < 0.05) related to hospital volume, but the surgeon's experience is not significantly related to perioperative deaths when hospital volume is controlled. CONCLUSIONS: These data support a defined minimum hospital experience for elective pancreatectomy for malignancy to minimize perioperative deaths.

Unintended pregnancy and breast-feeding behavior.

OBJECTIVES: This study assessed the effect of unintended pregnancy on breast-feeding behavior. METHODS: All women delivering a live birth between January 1, 1995, and July 31, 1996 (n = 33,735), in the 15-county central New York region were asked whether they had intended to become pregnant and their breast-feeding plans. RESULTS: Women with mistimed pregnancies, and pregnancies that were not wanted were significantly less likely to breast-feed than were women whose pregnancies were planned. After adjustment for confounding variables and contraindications for breast-feeding, the odds ratios of not breast-feeding remained significant. CONCLUSIONS: Promoting breast-feeding among women with unintended pregnancies is important to improve health status.

Adult open heart surgery in New York State. An analysis of risk factors and hospital mortality rates.

This study analyzes data from New York State's new Cardiac Surgery Reporting System, which contains information about cardiac preoperative risk factors, postoperative complications, and hospital discharge. The purposes of the study were to determine the set of significant clinical risk factors and to identify cardiac surgical centers most likely to have serious quality-of-care problems. Significant risk factors for in-hospital death were age, gender, ejection fraction, previous myocardial infarction, number of open heart operations in previous admissions, diabetes requiring medication, dialysis dependence, disasters (acute structural defect, renal failure, cardiogenic shock, gunshot), unstable angina, intractable congestive heart failure, left main trunk narrowed more than 90%, and type of operation performed. Four of the 28 hospitals had significantly higher mortality rates than expected, given the risk factors of their patients. Subsequent site visits and medical record reviews confirmed that these facilities had high percentages of quality-of-care problems among cases resulting in mortality.

A methodology for targeting hospital cases for quality of care record reviews.

We tested the efficacy of selected case characteristics in targeting quality of care problems for medical record review. The case characteristics, all of which apply to patients who die in a hospital, consist primarily of procedures and DRGs (diagnosis-related groups) for which death rarely occurs, and a set of complications of surgical care. All characteristics are obtainable from combinations of the principal and secondary diagnoses and procedures in the case, and are available from discharge abstracts. The presence of a quality of care problem is confirmed through a review of the medical record by a nurse and two or more physicians. A logistic regression model that controls for various patient and hospital variables is used as a measure of each of the proposed case characteristics. The results indicate that most of the characteristics are associated with higher percentages of quality of care problems than cases chosen at random, and that the methodology has promise as a tool for targeting cases for medical record review.

Investigation of the relationship between volume and mortality for surgical procedures performed in New York State hospitals.

Recent studies have demonstrated that the number of times a hospital or surgeon performs certain procedures annually has an inverse relationship with in-hospital mortality rates for patients undergoing the procedures. This study uses an improved measure of physician volume to test the combined relationship of hospital and physician volume with in-hospital mortality rates and to explore the existence of threshold volumes that optimally discriminate high- and low-volume providers. Five procedure groups have significant volume-mortality relationships. For total cholecystectomies, hospital volume is the more significant volume measure, but physician volume is marginally related to mortality rate. For coronary artery bypass surgeries, resection of abdominal aortic aneurysms, partial gastrectomies, and colectomies, physician volume is more significant than hospital volume, but hospital volume is marginally significant. Annual hospital volume thresholds for these data appear to exist at approximately 5 procedures for partial gastrectomies, 40 procedures for colectomies, and 170 procedures for total cholecystectomies.

Gender differences in mortality rates for coronary artery bypass surgery.

This study utilized a state-wide data base containing clinical risk factors for cardiac surgery to investigate differences in in-hospital mortality rates for men and women undergoing coronary artery bypass surgery. The crude mortality rates for coronary artery bypass surgery for men and women were 3.08% and 5.43% respectively, in New York State in 1989. When logistic regression analysis was used to control for preoperative risk, gender remained a significant predictor of mortality. Risk-adjusted (indirectly standardized) mortality rates were 3.33% and 4.45% for men and women, respectively. The risk-adjusted odds ratio of women to men experiencing in-hospital death was 1.52 (95% confidence interval 1.25 to 1.90).

Coronary artery bypass surgery: the relationship between inhospital mortality rate and surgical volume after controlling for clinical risk factors.

This study uses a new database containing clinical risk factors for cardiac surgery to investigate the relationship between surgical volume (hospital and surgeon) and inhospital mortality rate for all patients receiving coronary artery bypass surgery in New York State in 1989. Also, hospitals with significantly higher and lower mortality rates than expected on the basis of patient preoperative risk factors are identified. The results demonstrate that both annual surgeon volume and annual hospital volume are significantly (inversely) related to mortality rate. The 36% of all coronary bypass operations performed in hospitals with annual bypass volumes of 700 or more by surgeons with annual bypass volumes of 180 or more had a risk-adjusted mortality rate of 2.67% in comparison to a risk-adjusted mortality rate of 4.29% for other bypass operations. Furthermore, low surgical volumes were a major contributor to the outlier status of four of the five hospitals with significantly higher mortality rates than expected.