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Biomedical subjects

John D Birkmeyer

Publications and source records attributed to John D Birkmeyer.

52 records · Page 3Linked to original sources
PubMed2003

Effects of hospital volume on life expectancy after selected cancer operations in older adults: a decision analysis.

BACKGROUND: In addition to lower operative mortality, patients undergoing selected cancer operations at high volume centers have improved longterm survival. We sought to determine the overall effect of hospital volume on life expectancy after cancer surgery. STUDY DESIGN: We used a Markov decision analysis model to estimate life expectancy for patients undergoing resection for pancreatic, lung, or colon cancer. Model inputs included probabilities of operative mortality and longterm survival. For input data, we examined operative mortality (in-hospital or within 30 days) stratified by volume in over 400,000 patients undergoing resection for these three cancers using the national Medicare database (1994-1999). Risks of late mortality were abstracted from published studies (MEDLINE, 1966 to present) to model the effect of hospital volume on longterm survival. In analysis, we first calculated life expectancy for patients undergoing surgery at very low, low, medium, high, and very high volume hospitals. We then explored the effects of various regionalization strategies. RESULTS: Life expectancy increased steadily with hospital volume for all three cancers. Life expectancy after pancreatic cancer resection increased linearly with hospital volume: from 1.9 years at very low volume centers to 3.6 years at very high volume centers. For lung cancer, life expectancy ranged from 5.4 to 6.6 years. Increases in life expectancy for colon cancer were not as dramatic: from 6.8 at very low volume hospitals to 7.4 years at very high volume hospitals. Differences in life expectancy across volume strata were largely attributable to differences in longterm survival, not operative mortality. From a policy perspective, regionalizing surgery for colon cancer would produce the greatest overall life-expectancy gains, but it would require moving most patients. CONCLUSIONS: Patients aged 65 and older with pancreatic, lung, and colon cancer have substantially greater life expectancy after cancer resection at higher volume hospitals. Further work is needed to understand the mechanisms underlying differences in performance across hospitals in cancer care.

Aged↗
PubMed2003

Determining an appropriate threshold for referral to surgery for gastroesophageal reflux disease.

BACKGROUND: Persistent symptomatic gastroesophageal reflux disease (GERD) can be treated with medication or surgery. The purposes of this study were (1) to determine how poor the quality of life on medication would need to be to justify assuming the risks of surgery, and (2) to estimate the proportion of patients currently on medication whose quality of life is below this value. METHODS: We developed a Markov decision analysis model to simulate health outcomes (measured in quality adjusted life years [QALY]) over 10 years for medication and surgery in patients with typical GERD symptoms. We included probabilities of events obtained from a systematic literature review. Quality of life adjustments, expressed as utilities, were drawn from a survey of 131 patients 1 to 5 years after antireflux surgery. By using this model, we calculated what quality of life on medications would change the optimal strategy from medication to surgery (threshold). To determine the proportion of patients below this value, we prospectively surveyed 40 medically treated GERD patients at our hospital. RESULTS: Surgery resulted in more QALYs than medical therapy when the utility with medication use was below 0.90. Sensitivity analysis showed this value to be relatively insensitive to reasonable variations in surgical risks (mortality, failures, reoperation) and quality of life after surgery. Among those surveyed on medications, 48% fell below this threshold and would be predicted to benefit from surgery. CONCLUSION: Our model suggests that surgery would likely benefit a high proportion of medically treated GERD patients. Individual assessment of quality of life with GERD should be considered to aid clinical decision making.

Data Collection↗
PubMed2003

Trends in surgery for gastroesophageal reflux disease: the effect of laparoscopic surgery on utilization.

BACKGROUND: In addition to substituting for open surgery, minimally invasive surgery may lower thresholds for intervention and thus increase overall utilization rates. The degree to which laparoscopy may have lowered the threshold for elective anti-reflux surgery is unknown. METHODS: Using the Uniform Hospital Discharge Dataset and ICD-9 procedure and diagnosis codes, we identified all laparoscopic and open anti-reflux procedures performed on adults in Massachusetts, New Hampshire, and Vermont for each year from 1993 to 1998. We then examined secular trends and regional variation in the use of laparoscopic and open anti-reflux surgery. RESULTS: The population-based rate of anti-reflux surgery more than doubled between 1993 (4.8 per 100,000) and 1998 (11.7 per 100,000). Laparoscopic anti-reflux procedures increased more than 6-fold between 1993 and 1998, from 1.2 to 8.9 procedures per 100,000 adults, with accompanying declines in overall length of stay and mortality. However, the number of open anti-reflux procedures decreased only modestly (22%) over this time period. In the year hospitals performed their first laparoscopic anti-reflux operation, procedure rates nearly tripled, on average, and then increased slowly in subsequent years. In 1997 and 1998, rates of anti-reflux surgery varied nearly 5-fold across hospital referral regions, ranging from 5.4 to 24.5 per 100,000. CONCLUSIONS: With the growth of minimally invasive surgery, rates of anti-reflux surgery have increased substantially, with wide regional variation in intervention rates. Further research is needed to determine the appropriate threshold for surgical treatment in patients with gastroesophageal reflux.

Adolescent↗
PubMed2003

Hospital volume, length of stay, and readmission rates in high-risk surgery.

OBJECTIVE: Aimed at reducing surgical deaths, several recent initiatives have attempted to establish volume-based referral strategies in high-risk surgery. Although payers are leading the most visible of these efforts, it is unknown whether volume standards will also reduce resource use. METHODS: We studied postoperative length of stay and 30-day readmission rate after 14 cardiovascular and cancer procedures using the 1994-1999 national Medicare database (total n = 2.5 million). We used regression techniques to examine the relationship between length of stay, 30-day readmission, and hospital volume, adjusting for age, gender, race, comorbidity score, admission acuity, and mean social security income. RESULTS: Mean postoperative length of stay ranged from 3.4 days (carotid endarterectomy) to 19.6 days (esophagectomy). There was no consistent relationship between volume and mean length of stay; it significantly increased across volume strata for 7 of the 14 procedures and significantly decreased across volume strata for the other 7. Mean length of stay at very-low-volume and very-high-volume hospitals differed by more than 1 day for 6 procedures. Of these, the mean length of stay was shorter in high-volume hospitals for 3 procedures (pancreatic resection, esophagectomy, cystectomy), but longer for other procedures (aortic and mitral valve replacement, gastrectomy). The 30-day readmission rate also varied widely by procedure, ranging from 9.9% (nephrectomy) to 22.2% (mitral valve replacement). However, volume was not related to 30-day readmission rate with any procedure. CONCLUSION: Although hospital volume may be an important predictor of operative mortality, it is not associated with resource use as reflected by length of stay or readmission rates.

Cardiovascular Diseases↗
PubMed2002

Hospital volume and surgical mortality in the United States.

BACKGROUND: Although numerous studies suggest that there is an inverse relation between hospital volume of surgical procedures and surgical mortality, the relative importance of hospital volume in various surgical procedures is disputed. METHODS: Using information from the national Medicare claims data base and the Nationwide Inpatient Sample, we examined the mortality associated with six different types of cardiovascular procedures and eight types of major cancer resections between 1994 and 1999 (total number of procedures, 2.5 million). Regression techniques were used to describe relations between hospital volume (total number of procedures performed per year) and mortality (in-hospital or within 30 days), with adjustment for characteristics of the patients. RESULTS: Mortality decreased as volume increased for all 14 types of procedures, but the relative importance of volume varied markedly according to the type of procedure. Absolute differences in adjusted mortality rates between very-low-volume hospitals and very-high-volume hospitals ranged from over 12 percent (for pancreatic resection, 16.3 percent vs. 3.8 percent) to only 0.2 percent (for carotid endarterectomy, 1.7 percent vs. 1.5 percent). The absolute differences in adjusted mortality rates between very-low-volume hospitals and very-high-volume hospitals were greater than 5 percent for esophagectomy and pneumonectomy, 2 to 5 percent for gastrectomy, cystectomy, repair of a nonruptured abdominal aneurysm, and replacement of an aortic or mitral valve, and less than 2 percent for coronary-artery bypass grafting, lower-extremity bypass, colectomy, lobectomy, and nephrectomy. CONCLUSIONS: In the absence of other information about the quality of surgery at the hospitals near them, Medicare patients undergoing selected cardiovascular or cancer procedures can significantly reduce their risk of operative death by selecting a high-volume hospital.

Aged↗
PubMed2002

Short-term outcomes of laparoscopic and open ventral hernia repair: a meta-analysis.

BACKGROUND: Although laparoscopic repair of ventral hernia has become increasingly popular, its outcomes relative to open repair have not been well characterized. For this reason, we performed a meta-analysis of studies comparing open and laparoscopic ventral (including incisional) hernia repair. HYPOTHESIS: Laparoscopic ventral hernia repair results in better short-term outcomes than open ventral hernia repair. DATA SOURCES: Structured MEDLINE search for published studies. One unpublished study was also identified. STUDY SELECTION: Studies were selected on the basis of study design (comparison of laparoscopic and open ventral hernia repair). The 3 main outcome measures were perioperative complications, operative time, and length of hospital stay. Of 83 potential studies identified by abstract review, 8 (10%) met the inclusion criteria. DATA EXTRACTION: Two reviewers assessed each article to determine eligibility for inclusion and, where appropriate, abstracted information on patient characteristics and main outcome measures. DATA SYNTHESIS: Across 8 studies, 390 patients underwent open repair and 322 underwent laparoscopic repair. Perioperative complications were less than half as likely to occur in patients undergoing laparoscopic repair (14% vs 27%; P =.03; odds ratio, 0.42; 95% confidence interval, 0.29-0.68). Average length of stay was shorter in the laparoscopic group (2.0 vs 4.0 days; P =.02). No statistically significant difference in operative times was noted between laparoscopic and open repair (99 vs 96 minutes; P =.38). CONCLUSIONS: Laparoscopic ventral hernia repair offers lower complication rates and shorter length of stay than open repair. However, randomized controlled trials and studies with long-term follow-up are needed to confirm these findings and to assess long-term rates of hernia recurrence.

Confidence Intervals↗
PubMed2002

Is surgery getting safer? National trends in operative mortality.

BACKGROUND: Although mortality rates for some cardiovascular procedures seem to have declined, it is unclear whether other high-risk procedures are becoming safer over time. STUDY DESIGN: We examined national trends between 1994 and 1999 in operative mortality for 14 high-risk cardiovascular and cancer procedures in the national population of Medicare beneficiaries over age 65. Secular trends were examined using logistic regression adjusting for age, gender, race, socioeconomic status, admission acuity, comorbidities, and hospital volume. RESULTS: Observed mortality rates varied widely across the 14 procedures, from 2% (carotid endarterectomy) to 16% (esophagectomy). Over the 6-year study period, average patient age increased for all procedures, and patients were more likely to undergo operation at high-volume hospitals for some procedures (pancreatic resection, esophagectomy, cystectomy, and pneumonectomy). After accounting for these changes, operative mortality declined significantly for three cardiovascular procedures, as evidenced by adjusted odds ratios (OR) for the 6-year effect on operative mortality (coronary artery bypass graft OR = 0.85, 95% confidence interval [CI] 0.81 to 0.88; carotid endarterectomy OR = 0.86,95% CI 0.80 to 0.93; mitral valve replacement OR = 0.89, 95% CI 0.81 to 0.97). In contrast, operative mortality did not decline for any of the cancer procedures. In fact, adjusted mortality increased for colectomy for colon cancer (OR= 1.13, 95% CI 1.07 to 1.19). CONCLUSIONS: Although risks of some cardiovascular procedures are declining over time, there is no evidence that other types of high-risk surgery are becoming safer. These findings suggest the need for systematic efforts to monitor and improve surgical performance.

Aged↗
PubMed2002

Adjusting surgical mortality rates for patient comorbidities: more harm than good?

Background. Studies of medical admissions have questioned the validity of using claims data to adjust for preexisting medical conditions (comorbidities), but the impact of using comorbidities from claims data to risk-adjust mortality rates for high-risk surgery is not well characterized. The purpose of this study was to evaluate the relationship between comorbidities and mortality in administrative data in surgical populations and identify better risk-adjustment methods. Methods. Using the national Medicare database (1994-1997), we identified admissions for elective abdominal aortic aneurysm repair (140,577) and pancreaticoduodenectomy (10,530). We calculated the relative risk of mortality (adjusted for age, sex, race, and admission acuity) for 5 chronic conditions that are known (from clinical series) to increase the risk of postoperative mortality and are commonly used in claims-based risk-adjustment models. To explore the potential value of alternative risk-adjustment strategies, we examined relationships between surgical mortality and comorbidities using diagnosis codes identified from previous admissions. Results. Overall, in-hospital mortality for elective abdominal aortic aneurysm (AAA) repair and pancreaticoduodenectomy were 5.1% and 10.4%, respectively. For both procedures, 3 of the 5 comorbidities were associated with decreased risk of mortality: prior myocardial infarction (MI) [RR = 0.38; 95% confidence interval (CI), 0.33-0.43 for AAA; RR = 0.38; 95% CI, 0.21-0.69 for pancreaticoduodenectomy), malignancy (RR = 0.67; 95% CI, 0.59-0.76 for AAA; RR = 0.74; 95% CI, 0.45-1.21 for pancreaticoduodenectomy], and diabetes (RR = 0.76; 95% CI, 0.64-0.84 for AAA; RR = 0.59; 95% CI, 0.49-0.69 for pancreaticoduodenectomy). Using comorbidities identified from prior admissions increased the mortality risk estimates for prior MI (RR = 1.22; 95% CI, 1.08-1.38 for AAA; RR = 0.80; 95% CI, 0.49-1.30 for pancreaticoduodenectomy) and diabetes (RR = 1.41; 95% CI, 1.25-1.59 for AAA; RR = 0.94; 95% CI, 0.78-1.14 for pancreaticoduodenectomy). Conclusions. Because comorbidities coded on the index admission appear protective, incorporating them in risk-adjustment models for studies comparing surgical performance may penalize providers for taking care of sicker patients. When available, comorbidity information from prior hospitalizations may be more useful for risk adjustment.

Aortic Aneurysm, Abdominal↗
PubMed1993

Economic impact of inappropriate blood transfusions in coronary artery bypass graft surgery.

PURPOSE: In addition to historically important issues of blood inventory and blood safety, the costs of blood transfusion are anticipated to have an increasingly important impact on transfusion practices. To address this, we analyzed costs of blood support given to patients undergoing coronary artery bypass graft (CABG) surgery, along with costs of blood components whose transfusions were identified to be unnecessary. PATIENTS AND METHODS: Blood components transfused as part of a previously reported national, multicenter audit of 30 adult patients each at 18 institutions undergoing primary, elective CABG surgery were reviewed. RESULTS: The range of blood purchase costs among institutions was broad, varying over two-fold. The range of red cell units transfused varied over 10-fold, and the range of total components transfused varied over 40-fold. The number of blood components transfused unnecessarily represented 27% of all blood units transfused, ranging from 7% to 43% among institutions. Inappropriate transfusions accounted for 47%, 32%, and 15% of all platelet, plasma, and red cell units transfused. The mean institutional cost for all blood components transfused per patient was $397 +/- $244. The cost per patient of components transfused inappropriately was 24% of this, or $96 +/- $89 (mean +/- SD). CONCLUSION: These costs could be reduced with practice guidelines and quality improvement programs aimed at reducing the number of inappropriate transfusions.

Adult↗
PubMedDate not supplied

National trends in utilization and in-hospital outcomes of bariatric surgery.

In view of recent enthusiasm for surgery to treat morbid obesity, we examined national changes in utilization and in-hospital outcomes of bariatric surgery over time. With the use of International Classification of Diseases (ICD-9) codes, we identified all bariatric procedures (n = 12,203) performed on adults from 1990 to 1997 in hospitals participating in the Nationwide Inpatient Sample. We then applied sampling weights and United States Census data to calculate the national population-based rates of bariatric surgery procedures for each year and examined secular trends in utilization. We further evaluated changes in patient characteristics and in-hospital mortality and complications. From 1990 to 1997, the national annual rate of bariatric surgery increased from 2.7 to 6.3 per 100,000 adults (P < 0.001). The percentage of bariatric procedures performed by gastric bypass increased from 52% to 84% (P < 0.001). Patients were slightly older (38.1 years vs. 40.3 years; P < 0.001) with more comorbid conditions (20.9% vs. 31.6%; P < 0.001) in 1997 vs. 1990. In-hospital mortality was 0.37% overall and remained stable. Rates of pulmonary emboli, early reoperation, and pulmonary complications declined significantly over time. Between 1990 and 1997, the annual rate of bariatric surgery in the United States more than doubled, without substantial changes in perioperative morbidity or mortality. This trend was largely associated with an increase in the use of gastric bypass procedures.

Adult↗
PubMedDate not supplied

Will volume-based referral strategies reduce costs or just save lives?

Although recent policy initiatives aimed at concentrating selected surgical procedures in high-volume hospitals may reduce mortality, their economic implications have not been considered fully. From the hospital perspective, the primary effect of these policies will be to redistribute surgical profits to bigger centers. From the payer perspective, prices paid for procedures will likely increase in some geographic areas. From the societal perspective, how these policies will affect the true cost of providing surgical care is uncertain, but use of discretionary procedures will likely increase. For these reasons, the primary argument for volume-based referral strategies should be improving quality, not reducing costs.

Economics, Hospital↗