Surgeon volume and operative mortality in the United States

BACKGROUND

Although the relation between hospital volume and surgical mortality is well established, for most procedures, the relative importance of the experience of the operating surgeon is uncertain.

METHODS

Using information from the national Medicare claims data base for 1998 through 1999, we examined mortality among all 474,108 patients who underwent one of eight cardiovascular procedures or cancer resections. Using nested regression models, we examined the relations between operative mortality and surgeon volume and hospital volume (each in terms of total procedures performed per year), with adjustment for characteristics of the patients and other characteristics of the providers.

RESULTS

Surgeon volume was inversely related to operative mortality for all eight procedures (P=0.003 for lung resection, P<0.001 for all other procedures). The adjusted odds ratio for operative death (for patients with a low-volume surgeon vs. those with a high-volume surgeon) varied widely according to the procedure--from 1.24 for lung resection to 3.61 for pancreatic resection. Surgeon volume accounted for a large proportion of the apparent effect of the hospital volume, to an extent that varied according to the procedure: it accounted for 100 percent of the effect for aortic-valve replacement, 57 percent for elective repair of an abdominal aortic aneurysm, 55 percent for pancreatic resection, 49 percent for coronary-artery bypass grafting, 46 percent for esophagectomy, 39 percent for cystectomy, and 24 percent for lung resection. For most procedures, the mortality rate was higher among patients of low-volume surgeons than among those of high-volume surgeons, regardless of the surgical volume of the hospital in which they practiced.

CONCLUSIONS

For many procedures, the observed associations between hospital volume and operative mortality are largely mediated by surgeon volume. Patients can often improve their chances of survival substantially, even at high-volume hospitals, by selecting surgeons who perform the operations frequently.

National trends in lower extremity bypass surgery, endovascular interventions, and major amputations

INTRODUCTION

Advances in endovascular interventions have expanded the options available for the invasive treatment of lower extremity peripheral arterial disease (PAD). Whether endovascular interventions substitute for conventional bypass surgery or are simply additive has not been investigated, and their effect on amputation rates is unknown.

METHODS

We sought to analyze trends in lower extremity endovascular interventions (angioplasty and atherectomy), lower extremity bypass surgery, and major amputation (above and below-knee) in Medicare beneficiaries between 1996 and 2006. We used 100% samples of Medicare Part B claims to calculate annual procedure rates of lower extremity bypass surgery, endovascular interventions (angioplasty and atherectomy), and major amputation between 1996 and 2006. Using physician specialty identifiers, we also examined trends in the specialty performing the primary procedure.

RESULTS

Between 1996 and 2006, the rate of major lower extremity amputation declined significantly (263 to 188 per 100,000; risk ratio [RR] 0.71, 95% confidence interval [CI] 0.6-0.8). Endovascular interventions increased more than threefold (from 138 to 455 per 100,000; RR = 3.30; 95% CI: 2.9-3.7) while bypass surgery decreased by 42% (219 to 126 per 100,000; RR = 0.58; 95% CI: 0.5-0.7). The increase in endovascular interventions consisted both of a growth in peripheral angioplasty (from 135 to 337 procedures per 100,000; RR = 2.49; 95% CI: 2.2-2.8) and the advent of percutaneous atherectomy (from 3 to 118 per 100,000; RR = 43.12; 95% CI: 34.8-52.0). While radiologists performed the majority of endovascular interventions in 1996, more than 80% were performed by cardiologists and vascular surgeons by 2006. Overall, the total number of all lower extremity vascular procedures almost doubled over the decade (from 357 to 581 per 100,000; RR = 1.63; 95% CI: 1.5-1.8).

CONCLUSION

Endovascular interventions are now performed much more commonly than bypass surgery in the treatment of lower extremity PAD. These changes far exceed simple substitution, as more than three additional endovascular interventions were performed for every one procedure declined in lower extremity bypass surgery. During this same time period, major lower extremity amputation rates have fallen by more than 25%. However, further study is needed before any causal link can be established between lower extremity vascular procedures and improved rates of limb salvage in patients with PAD.

Surgery or Endovascular Therapy for Chronic Limb-Threatening Ischemia

BACKGROUND

Patients with chronic limb-threatening ischemia (CLTI) require revascularization to improve limb perfusion and thereby limit the risk of amputation. It is uncertain whether an initial strategy of endovascular therapy or surgical revascularization for CLTI is superior for improving limb outcomes.

METHODS

In this international, randomized trial, we enrolled 1830 patients with CLTI and infrainguinal peripheral artery disease in two parallel-cohort trials. Patients who had a single segment of great saphenous vein that could be used for surgery were assigned to cohort 1. Patients who needed an alternative bypass conduit were assigned to cohort 2. The primary outcome was a composite of a major adverse limb event - which was defined as amputation above the ankle or a major limb reintervention (a new bypass graft or graft revision, thrombectomy, or thrombolysis) - or death from any cause.

RESULTS

In cohort 1, after a median follow-up of 2.7 years, a primary-outcome event occurred in 302 of 709 patients (42.6%) in the surgical group and in 408 of 711 patients (57.4%) in the endovascular group (hazard ratio, 0.68; 95% confidence interval [CI], 0.59 to 0.79; P<0.001). In cohort 2, a primary-outcome event occurred in 83 of 194 patients (42.8%) in the surgical group and in 95 of 199 patients (47.7%) in the endovascular group (hazard ratio, 0.79; 95% CI, 0.58 to 1.06; P = 0.12) after a median follow-up of 1.6 years. The incidence of adverse events was similar in the two groups in the two cohorts.

CONCLUSIONS

Among patients with CLTI who had an adequate great saphenous vein for surgical revascularization (cohort 1), the incidence of a major adverse limb event or death was significantly lower in the surgical group than in the endovascular group. Among the patients who lacked an adequate saphenous vein conduit (cohort 2), the outcomes in the two groups were similar. (Funded by the National Heart, Lung, and Blood Institute; BEST-CLI ClinicalTrials.gov number, NCT02060630.).

Hospital volume and operative mortality in cancer surgery: a national study

BACKGROUND

Although initiatives to regionalize cancer surgery are already under way, the relative importance of volume in cancer surgery is disputed.

HYPOTHESIS

We examined surgical mortality with 8 cancer resections in the US population to better quantify the influence of hospital volume.

METHODS

Using information from the all-payer Nationwide Inpatient Sample (1995-1997), we examined mortality with 8 cancer resections (N = 195 152). After dividing patients into 3 evenly sized volume groups based on hospital procedure volume (low, medium, and high), we used regression techniques to describe relationships between hospital volume and in-hospital mortality, adjusting for patient characteristics.

RESULTS

Trends toward lower operative risks at high-volume hospitals were observed for 7 of the 8 procedures. However, differences between low- and high high-volume hospitals were statistically significant for only 3 operations (esophagectomy, 15.0% vs 6.5%; pancreatic resection, 13.1% vs 2.5%; and pulmonary lobectomy, 10.1% vs 8.9%, respectively). Although they did not reach statistical significance, absolute differences in mortality between low- and high-volume hospitals were greater than 1% for the following 3 procedures: gastrectomy, 8.7% vs 6.9%; cystectomy, 3.6% vs 2.5%; and pneumonectomy, 10.6% vs 8.9%, respectively. Mortality reductions for nephrectomy and colectomy were small. In general, in terms of absolute differences in mortality, the effect of volume was greatest in elderly patients.

CONCLUSIONS

Operative mortality decreases with increasing hospital volume for several cancer resections. However, volume may be most important in patients who are older and at higher risk.

Epidemiology and Risk of Amputation in Patients With Diabetes Mellitus and Peripheral Artery Disease

Peripheral artery disease (PAD) stems from atherosclerosis of lower extremity arteries with resultant arterial narrowing or occlusion. The most severe form of PAD is termed chronic limb-threatening ischemia and carries a significant risk of limb loss and cardiovascular mortality. Diabetes mellitus is known to increase the incidence of PAD, accelerate disease progression, and increase disease severity. Patients with concomitant diabetes mellitus and PAD are at high risk for major complications, such as amputation. Despite a decrease in the overall number of amputations performed annually in the United States, amputation rates among those with both diabetes mellitus and PAD have remained stable or even increased in high-risk subgroups. Within this cohort, there is significant regional, racial/ethnic, and socioeconomic variation in amputation risk. Specifically, residents of rural areas, African-American and Native American patients, and those of low socioeconomic status carry the highest risk of amputation. The burden of amputation is severe, with 5-year mortality rates exceeding those of many malignancies. Furthermore, caring for patients with PAD and diabetes mellitus imposes a significant cost to the healthcare system-estimated to range from $84 billion to $380 billion annually. Efforts to improve the quality of care for those with PAD and diabetes mellitus must focus on the subgroups at high risk for amputation and the disparities they face in the receipt of both preventive and interventional cardiovascular care. Better understanding of these social, economic, and structural barriers will prove to be crucial for cardiovascular physicians striving to better care for patients facing this challenging combination of chronic diseases.

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.

Survival after open versus endovascular thoracic aortic aneurysm repair in an observational study of the Medicare population

BACKGROUND

The goal of this study was to describe short- and long-term survival of patients with descending thoracic aortic aneurysms (TAAs) after open and endovascular repair (TEVAR).

METHODS AND RESULTS

Using Medicare claims from 1998 to 2007, we analyzed patients who underwent repair of intact and ruptured TAA, identified from a combination of procedural and diagnostic International Classification of Disease, ninth revision, codes. Our main outcome measure was mortality, defined as perioperative mortality (death occurring before hospital discharge or within 30 days), and 5-year survival, from life-table analysis. We examined outcomes across repair type (open repair or TEVAR) in crude, adjusted (for age, sex, race, procedure year, and Charlson comorbidity score), and propensity-matched cohorts. Overall, we studied 12 573 Medicare patients who underwent open repair and 2732 patients who underwent TEVAR. Perioperative mortality was lower in patients undergoing TEVAR compared with open repair for both intact (6.1% versus 7.1%; P=0.07) and ruptured (28% versus 46%; P<0.0001) TAA. However, patients with intact TAA selected for TEVAR had significantly worse survival than open patients at 1 year (87% for open, 82% for TEVAR; P=0.001) and 5 years (72% for open; 62% for TEVAR; P=0.001). Furthermore, in adjusted and propensity-matched cohorts, patients selected for TEVAR had worse 5-year survival than patients selected for open repair.

CONCLUSIONS

Although perioperative mortality is lower with TEVAR, Medicare patients selected for TEVAR have worse long-term survival than patients selected for open repair. The results of this observational study suggest that higher-risk patients are being offered TEVAR and that some do not benefit on the basis of long-term survival. Future work is needed to identify TEVAR candidates unlikely to benefit from repair.

Do cancer centers designated by the National Cancer Institute have better surgical outcomes?

BACKGROUND

The National Cancer Institute (NCI) designates cancer centers as regional centers of excellence in research and patient care. Although these centers often advertise their superior outcomes, their relative performance has not been examined empirically. In the current study, the authors assessed whether patients at NCI cancer centers compared with patients at control hospitals had lower mortality rates after major cancer surgery.

METHODS

Using the national Medicare database (1994-1999), the authors assessed surgical mortality and late survival rates for 63,860 elderly patients undergoing resection for lung, esophageal, gastric, pancreatic, bladder, or colon carcinoma. For assessing performance, patients treated at the 51 NCI cancer centers were compared with patients from 51 control hospitals with the highest volumes for each procedure. Mortality rates (surgical and 5-year rates) were adjusted for patient characteristics and residual differences in procedure volume.

RESULTS

NCI cancer centers had lower adjusted surgical mortality rates than control hospitals for 4 of the 6 procedures, including colectomy (5.4% vs. 6.7%; P = 0.026), pulmonary resection (6.3% vs. 7.9%; P = 0.010), gastrectomy (8.0% vs. 12.2%; P < 0.001), and esophagectomy (7.9% vs. 10.9%; P = 0.027). Nonsignificant trends toward lower adjusted operative mortality rates at NCI cancer centers were also observed for cystectomy and pancreatic resection. Among patients surviving surgery, however, there were no important differences in subsequent 5-year mortality rates between NCI cancer centers and control hospitals for any of the procedures.

CONCLUSIONS

For many cancer procedures, patients undergoing surgery at NCI-designated cancer centers had lower surgical mortality rates than those treated at comparably high-volume hospitals, but similar long-term survival rates.

National trends in open surgical, endovascular, and branched-fenestrated endovascular aortic aneurysm repair in Medicare patients

BACKGROUND

Open repair effectively prevents rupture for patients with abdominal aortic aneurysm (AAA) and is commonly studied as a metric reflecting hospital and surgeon expertise in cardiovascular care. However, given recent advances in endovascular aneurysm repair (EVAR), such as branched-fenestrated EVAR, it is unknown how commonly open surgical repair is still used in everyday practice.

METHODS

We analyzed trends in open AAA repair, EVAR, and branched-fenestrated EVAR for AAA in Medicare beneficiaries from 2003 to 2013. We used Medicare Part B claims to ascertain counts of these repair types annually during the study period. We assessed regional and national trends in characteristics of the patients and procedure volume.

RESULTS

Between 2003 and 2013, the total number of AAA repairs performed in fee-for-service Medicare patients declined by 26% from 31,582 to 23,421 (P < .001), after a peak number of 32,540 was performed in 2005 (28% decline since 2005). The number of open AAA repairs steadily declined by a total of 76%, from 20,533 in 2003 to 4916 in 2013 (P < .001). Whereas the number of EVARs increased from 11,049 in 2003 to 19,247 in 2011 (P < .001), it has since declined a total of 15% to only 16,362 repairs in 2013 (P < .001). After its introduction in 2011, the number of branched-fenestrated EVAR cases continuously rose from 335 procedures in 2011 to 2143 procedures in 2013 (P < .001). By 2013, virtually all hospital referral regions in the United States had rates of open AAA repair that would have been in the lowest quintile of volume in 2003.

CONCLUSIONS

The number of open AAA repairs fell by nearly 80% during the last decade, whereas traditional EVAR declined slightly and branched-fenestrated EVAR rapidly disseminated into national practice. These results suggest that open AAA repair is now performed too infrequently to be used as a metric in the assessment of hospital and surgeon quality in cardiovascular care. Furthermore, surgical training paradigms will need to reflect the changing dynamics necessary to ensure that surgeons and interventionists can safely perform these high-risk surgical procedures.

Association of Statin Dose With Amputation and Survival in Patients With Peripheral Artery Disease

BACKGROUND

Statin dose guidelines for patients with peripheral artery disease (PAD) are largely based on coronary artery disease and stroke data. The aim of this study is to determine the effect of statin intensity on PAD outcomes of amputation and mortality.

METHODS

Using an observational cohort study design and a validated algorithm, we identified patients with incident PAD (2003-2014) in the national Veterans Affairs data. Highest statin intensity exposure (high-intensity versus low-to-moderate-intensity versus antiplatelet therapy but no statin use) was determined within 1 year of diagnosis of PAD. Outcomes of interest were lower extremity amputations and death. The association of statin intensity with incident amputation and mortality was assessed with Kaplan-Meier plots, Cox proportional hazards modeling, propensity score-matched analysis, and sensitivity and subgroup analyses, as well, to reduce confounding.

RESULTS

In 155 647 patients with incident PAD, more than a quarter (28%) were not on statins. Use of high-intensity statins was lowest in patients with PAD only (6.4%) in comparison with comorbid coronary/carotid disease (18.4%). Incident amputation and mortality risk declined significantly with any statin use in comparison with the antiplatelet therapy-only group. In adjusted Cox models, the high-intensity statin users were associated with lower amputation risk and mortality in comparison with antiplatelet therapy-only users (hazard ratio, 0.67; 95% confidence interval, 0.61-0.74 and hazard ratio, 0.74; 95% confidence interval, 0.70-0.77, respectively). Low-to-moderate-intensity statins also had significant reductions in the risk of amputation and mortality (hazard ratio amputation, 0.81; 95% confidence interval, 0.75- 0.86; hazard ratio death, 0.83; 95% confidence interval, 0.81-0.86) in comparison with no statins (antiplatelet therapy only), but effect size was significantly weaker than the high-intensity statins (P<0.001). The association of high-intensity statins with lower amputation and death risk remained significant and robust in propensity score-matched, sensitivity, and subgroup analyses.

CONCLUSIONS

Statins, especially high-intensity formulations, are underused in patients with PAD. This is the first population-based study to show that high-intensity statin use at the time of PAD diagnosis is associated with a significant reduction in limb loss and mortality in comparison with low-to-moderate-intensity statin users, and patients treated only with antiplatelet medications but not with statins, as well.

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.

Operator experience and carotid stenting outcomes in Medicare beneficiaries

CONTEXT

Although the efficacy of carotid stenting has been established in clinical trials, outcomes of the procedure based on operator experience are less certain in clinical practice.

OBJECTIVE

To assess association between outcomes and 2 measures of operator experience: annual volume and experience at the time of the procedure among new operators who first performed carotid stenting after a national coverage decision by the Centers for Medicare & Medicaid Services (CMS).

DESIGN, SETTING, AND PATIENTS

Observational study using administrative data on fee-for-service Medicare beneficiaries aged 65 years or older undergoing carotid stenting between 2005 and 2007.

MAIN OUTCOME MEASURE

Thirty-day mortality stratified by very low, low, medium, and high annual operator volumes (<6, 6-11, 12-23, and ≥24 procedures per year, respectively) and treatment early vs late during a new operator's experience (1st to 11th procedure and 12th procedure or higher).

RESULTS

During the study period, 24,701 procedures were performed by 2339 operators. Of these, 11,846 were performed by 1792 new operators who first performed carotid stenting after the CMS national coverage decision. Overall, 30-day mortality was 1.9% (n = 461) and rate of failure to use an embolic protection device was 4.8% (n = 1173). The median annual operator volume among Medicare beneficiaries was 3.0 per year (interquartile range, 1.4-6.5) and 11.6% of operators performed 12 or more procedures per year during the study period. Observed 30-day mortality was higher among patients treated by operators with lower annual volumes (2.5% [95% CI, 2.1%-2.9%], 1.9% [95% CI, 1.6%-2.3%], 1.6% [95% CI, 1.3%-1.9%], and 1.4% [95% CI, 1.1%-1.7%] across the 4 categories; P < .001) and among patients treated early (2.3%; 95% CI, 2.0%-2.7%) vs late (1.4%; 95% CI, 1.1%-1.9%; P < .001) during a new operator's experience. After multivariable adjustment, patients treated by very low-volume operators had a higher risk of 30-day mortality compared with patients treated by high-volume operators (adjusted odds ratio, 1.9; 95% CI, 1.4-2.7; P < .001). Similarly, we found a higher risk of 30-day mortality in patients treated early vs late during a new operator's experience (adjusted odds ratio, 1.7; 95% CI, 1.2-2.4; P = .001).

CONCLUSION

Among older patients undergoing carotid stenting, lower annual operator volume and early experience are associated with increased 30-day mortality.

Neoadjuvant chemoradiotherapy for esophageal carcinoma: a meta-analysis

BACKGROUND

The effectiveness in improving survival of neoadjuvant chemoradiotherapy (NCRT) in patients undergoing surgery for esophageal carcinoma remains unclear.

METHODS

MEDLINE, the Cochrane Database of Systematic Reviews, BIOSIS Previews, and other resources were searched from January 1966 through January 2003. Randomized trials were selected on the basis of study design (NCRT followed by surgery vs surgery alone). Of 21 potential studies identified by abstract review, 6 (29%) met the inclusion criteria.

RESULTS

Across 6 studies, a total of 374 patients underwent NCRT followed by surgery and 364 underwent surgery alone. In 5 of the 6 studies in our meta-analysis, there was a small, non-statistically significant trend toward improved survival with NCRT. Only 1 study demonstrated a statistically significant benefit to NCRT. In our summary measure for all 6 studies, we found a small, non-statistically significant trend toward improved long-term survival in the NCRT followed by surgery group (relative risk of death in the NCRT group [RR], 0.86; 95% confidence interval [CI], 0.74 to 1.01; P = .07).

CONCLUSIONS

NCRT followed by surgery is associated with a small, non-statistically significant improvement in overall survival. Whether this benefit is sufficient to warrant the considerable expense and risks associated with NCRT should be the subject of future larger randomized trials.

Surgeon specialty and operative mortality with lung resection

OBJECTIVE

We sought to examine the effect of subspecialty training on operative mortality following lung resection.

SUMMARY BACKGROUND DATA

While several different surgical subspecialists perform lung resection for cancer, many believe that this procedure is best performed by board-certified thoracic surgeons.

METHODS

Using the national Medicare database 1998 to 1999, we identified patients undergoing lung resection (lobectomy or pneumonectomy) for lung cancer. Operating surgeons were identified by unique physician identifier codes contained in the discharge abstract. We used the American Board of Thoracic Surgery database, as well as physician practice patterns, to designate surgeons as general surgeons, cardiothoracic surgeons, or noncardiac thoracic surgeons. Using logistic regression models, we compared operative mortality across surgeon subspecialties, adjusting for patient, surgeon, and hospital characteristics.

RESULTS

Overall, 25,545 Medicare patients underwent lung resection, 36% by general surgeons, 39% by cardiothoracic surgeons, and 25% by noncardiac thoracic surgeons. Patient characteristics did not differ substantially by surgeon specialty. Adjusted operative mortality rates were lowest for cardiothoracic and noncardiac thoracic surgeons (7.6% general surgeons, 5.6% cardiothoracic surgeons, 5.8% noncardiac thoracic surgeons, P = 0.001). In analyses restricted to high-volume surgeons (>20 lung resections/y), mortality rates were lowest for noncardiac thoracic surgeons (5.1% noncardiac thoracic, 5.2% cardiothoracic, and 6.1% general surgeons) (P < 0.01 for difference between general surgeons and thoracic surgeons). In analyses restricted to high-volume hospitals (>45 lung resections/y), mortality rates were again lowest for noncardiac thoracic surgeons (5.0% noncardiac thoracic, 5.3% cardiothoracic, and 6.1% general surgeons) (P < 0.01 for differences between all 3 groups).

CONCLUSIONS

Operative mortality with lung resection varies by surgeon specialty. Some, but not all, of this variation in operative mortality is attributable to hospital and surgeon volume.

Readmission destination and risk of mortality after major surgery: an observational cohort study

BACKGROUND

Hospital readmissions are common after major surgery, although it is unknown whether patients achieve improved outcomes when they are readmitted to, and receive care at, the index hospital where their surgical procedure was done. We examined the association between readmission destination and mortality risk in the USA in Medicare beneficiaries after a range of common operations.

METHODS

By use of claims data from Medicare beneficiaries in the USA between Jan 1, 2001, and Nov 15, 2011, we assessed patients who needed hospital readmission within 30 days after open abdominal aortic aneurysm repair, infrainguinal arterial bypass, aortobifemoral bypass, coronary artery bypass surgery, oesophagectomy, colectomy, pancreatectomy, cholecystectomy, ventral hernia repair, craniotomy, hip replacement, or knee replacement. We used logistic regression models incorporating inverse probability weighting and instrumental variable analysis to measure associations between readmission destination (index vs non-index hospital) and risk of 90 day mortality for patients who underwent surgery who needed hospital readmission.

FINDINGS

9,440,503 patients underwent one of 12 major operations, and the number of patients readmitted or transferred back to the index hospital where their operation was done varied from 186,336 (65·8%) of 283,131 patients who were readmitted after coronary artery bypass grafting, to 142,142 (83·2%) of 170,789 patients who were readmitted after colectomy. Readmission was more likely to be to the index hospital than to a non-index hospital if the readmission was for a surgical complication (189,384 [23%] of 834,070 patients readmitted to index hospital vs 36,792 [13%] of 276,976 patients readmitted non-index hospital, p<0·0001). Readmission to the index hospital was associated with a 26% lower risk of 90 day mortality than was readmission to a non-index hospital, with inverse probability weighting used to control for selection bias (odds ratio [OR] 0·74, 95% CI 0·66-0·83). This effect was significant (p<0·0001) for all procedures in inverse probability-weighted models, and was largest for patients who were readmitted after pancreatectomy (OR 0·56, 95% CI 0·45-0·69) and aortobifemoral bypass (OR 0·69, 95% CI 0·61-0·77). By use of hospital-level variation among regional index hospital readmission rates as an instrument, instrumental variable analysis showed that the patients with the highest probability of returning to the index hospital had 8% lower risk of mortality (OR 0·92 95% CI 0·91-0·94) than did patients who were less likely to be readmitted to the index hospital.

INTERPRETATION

In the USA, patients who are readmitted to hospital after various major operations consistently achieve improved survival if they return to the hospital where their surgery took place. These findings might have important implications for cost-effectiveness-driven regional centralisation of surgical care.

FUNDING

None.

Long-term results of combined common femoral endarterectomy and iliac stenting/stent grafting for occlusive disease

BACKGROUND

Common femoral artery (CFA) endarterectomy with iliac stenting or stent grafting can be an alternative to traditional open surgery in patients with aortoiliac occlusive disease. We report the long-term outcomes of this approach.

METHODS

Patients undergoing CFA endarterectomy with simultaneous iliac stenting/stent grafting between 1997 and 2006 were retrospectively reviewed. Technical success, clinical and hemodynamic outcomes, and 5-year patency using life-table methodology were determined. Factors associated with reintervention and mortality were determined by logistic regression analysis.

RESULTS

A total of 171 patients (mean age, 67 +/- 10 years; 38% female; 35% diabetic) underwent 193 CFA endarterectomies and iliac stent/stent grafting. Indications were rest pain (32%), tissue loss (22%), and claudication (46%). External iliac artery (EIA) lesions were present in 39%, and combined common iliac artery (CIA) and EIA lesions were seen in 61% of patients. Complete CIA/EIA occlusions were present in 41% of patients. Stent grafts were used in 41% of patients. Technical success occurred in 98% of patients. Clinical improvement was seen in 92% of patients. Mean ankle-brachial index increased from 0.38 +/- 0.32 to 0.72 +/- 0.24. Median length of stay was 2 days (range, 1-51 days). Thirty-day mortality was 2.3% and 5-year survival was 60%. Five-year primary, primary-assisted, and secondary patencies were 60%, 97%, and 98% respectively. Endovascular reintervention was required in 14% of patients; inflow surgical procedures were required in 10%. By logistic regression analysis, use of stent grafts compared with bare stents was associated with significantly higher primary patency (87% +/- 5% vs 53% +/- 7%; P < .01).

CONCLUSION

Combined CFA endarterectomy with iliac intervention yield acceptable long-term results. The use of stent grafts compared with bare stents is associated with improved primary patency.

Variation in the use of lower extremity vascular procedures for critical limb ischemia

BACKGROUND

Many believe that variation in vascular practice may affect limb salvage rates in patients with severe peripheral arterial disease. However, the extent of variation in procedural vascular care obtained by patients with critical limb ischemia (CLI) remains unknown.

METHODS AND RESULTS

By using Medicare 2003 to 2006 data, we identified all patients with CLI who underwent major lower extremity amputation in the 306 hospital referral regions described in the Dartmouth Atlas of Healthcare. For each patient, we studied the use of lower extremity vascular procedures (open surgery or endovascular intervention) in the year before amputation. Our main outcome measure was the intensity of vascular care, defined as the proportion of patients in the hospital referral region undergoing a vascular procedure in the year before amputation. Overall, 20,464 patients with CLI underwent major lower extremity amputations during the study period, and collectively underwent 25,800 vascular procedures in the year before undergoing amputation. However, these procedures were not distributed evenly: 54% of patients had no vascular procedures performed in the year before amputation, 14% underwent 1 vascular procedure, and 32% underwent >1 vascular procedure. In the regions in the lowest quintile of vascular intensity, vascular procedures were performed in 32% of patients. Conversely, in the regions in the highest quintile of vascular intensity, revascularization was performed in 58% of patients in the year before amputation (P<0.0001). In analyses accounting for differences in age, sex, race, and comorbidities, patients in high-intensity regions were 2.4 times as likely to undergo revascularization in the year before amputation than patients in low-intensity regions (adjusted odds ratio, 2.4; 95% CI, 2.1-2.6; P<0.001).

CONCLUSIONS

Significant variation exists in the intensity of vascular care provided to patients in the year before major amputation. In some regions, patients receive intensive care, whereas in other regions, far less vascular care is provided. Future work is needed to determine the association between intensity of vascular care and limb salvage.

Regional intensity of vascular care and lower extremity amputation rates

OBJECTIVE

Because patient-level differences do not fully explain the variation in lower extremity amputation rates across the United States, we hypothesized that variation in intensity of vascular care may also affect regional rates of amputation and examined the relationship between the intensity of vascular care and the population-based rate of major lower extremity amputation (above-knee or below-knee) from vascular disease.

METHODS

Intensity of vascular care was defined as the proportion of Medicare patients who underwent any vascular procedure in the year before amputation, calculated at the regional level (2003 to 2006), using the 306 hospital referral regions in the Dartmouth Atlas of Healthcare. The relationship between intensity of vascular care and major amputation rate, at the regional level, was examined between 2007 and 2009.

RESULTS

Amputation rates varied widely by region, from one to 27 per 10,000 Medicare patients. Compared with regions in the lowest quintile of amputation rate, patients in the highest quintile were commonly African American (50% vs 13%) and diabetic (38% vs 31%). Intensity of vascular care also varied across regions: <35% of patients underwent revascularization in the lowest quintile of intensity, whereas nearly 60% underwent revascularization in the highest quintile. Overall, an inverse correlation was found between intensity of vascular care and the amputation rate, ranging from R = -0.36 for outpatient diagnostic and therapeutic procedures to R = -0.87 for inpatient surgical revascularizations. Analyses adjusting for patient characteristics and socioeconomic status found patients in high-intensity vascular care regions were significantly less likely to undergo amputation without an antecedent attempt at revascularization (odds ratio, 0.37; 95% confidence interval, 0.34-0.37; P < .001).

CONCLUSIONS

The intensity of vascular care provided to patients at risk for amputation varies, and regions with the most intensive vascular care have the lowest amputation rate, although the observational nature of these associations do not impart causality. High-risk patients, especially African American diabetic patients residing in low-intensity vascular care regions, represent an important target for systematic efforts to reduce amputation risk.

A prospective study comparing the complication rates between laparoscopic and open ventral hernia repairs

BACKGROUND

Although ventral hernia repair is increasingly performed laparoscopically, complication rates with this procedure are not well characterized. For this reason, we performed a prospective study comparing early outcomes after laparoscopic and open ventral hernia repairs.

METHODS

We identified all the patients undergoing ventral (including incisional) hernia repair at a single tertiary care center between September 1, 1999 and July 1, 2001 (overall n = 257). To increase the homogeneity of the sample, we excluded umbilical hernia repairs, parastomal hernia repairs, nonelective procedures, procedures not involving mesh, and repairs performed concurrently with another surgical procedure. Postoperative complications (in-hospital or within 30-days) were assessed prospectively according to standardized definitions by trained nurse clinicians.

RESULTS

Of the 136 ventral hernia repairs that met the study criteria, 65 (48%) were laparoscopic repairs (including 3 conversions to open surgery) and 71 (52%) were open repairs. The patients in the laparoscopic group were more likely to have undergone a prior (failed) ventral hernia repair (40% vs 27%; p = 0.14), but other patient characteristics were similar between the two groups. Overall, fewer complications were experienced by patients undergoing laparoscopic repair (8% vs 21%; p = 0.03). The higher complication rate in the open ventral hernia repair group came from wound infections (8%) and postoperative ileus (4%), neither of which was observed in the patients who underwent laparoscopic repair. The laparoscopic group had longer operating room times (2.2 vs 1.7 h; p = 0.001), and there was a nonsignificant trend toward shorter hospital stays with laparoscopic repair (1.1 vs 1.5 days; p = 0.10).

CONCLUSIONS

The patients undergoing laparoscopic repair had fewer postoperative complications than those receiving open repair. Wound infections and postoperative ileus accounted for the higher complication rates in the open ventral hernia repair group. Otherwise, these groups were very similar. Long-term studies assessing hernia recurrence rates will be required to help determine the optimal approach to ventral hernia repair.

Population-Based Assessment of the Incidence of Aortic Dissection, Intramural Hematoma, and Penetrating Ulcer, and Its Associated Mortality From 1995 to 2015

Background Aortic syndromes (ASs), including aortic dissection, intramural hematoma, and penetrating aortic ulcer, carry significant acute and long-term morbidity and mortality. However, the contemporary incidence and outcomes of AS are unknown. Methods and Results We used the Rochester Epidemiology Project record linkage system to identify all Olmsted County, MN, residents with AS (1995-2015). Diagnostic imaging, medical records, and death certificates were reviewed to confirm the diagnosis and AS subtype. Age- and sex-adjusted incidence rates were estimated using annual county-level census data. Survival for patients with AS was compared with age- and sex-matched controls using Cox regression to adjust for comorbid conditions. We identified 133 patients with AS (77, aortic dissection; 21, intramural hematoma; and 35, penetrating aortic ulcer). Average age was 71.8 years (SD=14.1), and 57% were men. The age- and sex-adjusted incidence was 7.7 per 100 000 person-years, was higher for men than women (10.2 versus 5.7 per 100 000 person-years), and increased with age. Among subtypes, the incidence of aortic dissection was highest (4.4 per 100 000 person-years), whereas the incidence of penetrating aortic ulcer and intramural hematoma was lower (2.1 and 1.2 per 100 000 person-years). Overall, the incidence of AS was stable over time ( P trend=0.33), although the incidence of penetrating aortic ulcer seemed to increase from 0.6 to 2.6 per 100 000 person-years ( P=0.008) with variability over the study interval. Patients with AS had more than twice the mortality rate at 5, 10, and 20 years when compared with population-based controls (5-, 10-, and 20-year mortality 39%, 57%, and 91% versus 18%, 41%, and 66%; overall adjusted mortality hazards ratio=2.1; P<0.001). Survival was lower than expected up to 90 days after AS diagnosis and did not differ significantly by subtype or by 5-year strata of diagnosis. Conclusions Overall, the incidence of aortic dissection and intramural hematoma has remained stable since 1995, despite the decline noted for other cardiovascular disease. AS confers increased early and long-term mortality that has not changed. These data highlight the need to improve long-term care to impact the prognosis of this patient group.

Specialty Training and Mortality After Esophageal Cancer Resection

BACKGROUND

Surgeons with advanced training have lower mortality rates with some surgical procedures. The objective of the current study was to investigate the impact of thoracic surgery training on mortality rates of esophageal cancer resection.

METHODS

We studied esophageal cancer resection in the national Medicare population during 1998 and 1999. Operative mortality rates (in-hospital or 30-day) were compared for thoracic surgeons and other surgeons, adjusting for patient characteristics, hospital volume, and surgeon volume. Surgeons with specialty training in thoracic surgery were those certified by the American Board of Thoracic Surgery.

RESULTS

Of the 1,946 patients, 625 (32%) had their operation performed by a thoracic surgeon. After adjustment for patient characteristics, mortality rates were 37% (odds ratio, 1.37; 95% confidence interval, 1.02 to 1.82) higher for surgeons without specialty training compared with thoracic surgeons (adjusted mortality 16.5% versus 12.4%; p = 0.01). However, differences in mortality between high-volume and low-volume hospitals (24.3% versus 11.4%; p < 0.001) and surgeons (20.7% versus 10.7%; p < 0.001) were larger than those between thoracic and general surgeons. Although thoracic surgeons had lower mortality rates after adjusting for hospital volume, the effect of thoracic surgery training was no longer significant after accounting for surgeon volume (odds ratio, 1.23; 95% confidence interval, 0.92 to 1.63).

CONCLUSIONS

Specialty training in thoracic surgery has an independent association with lower mortality after esophageal resection. But specialty training appears to be less important than hospital and surgeon volume.

Prior failed ipsilateral percutaneous endovascular intervention in patients with critical limb ischemia predicts poor outcome after lower extremity bypass

BACKGROUND

Although open surgical bypass remains the standard revascularization strategy for patients with critical limb ischemia (CLI), many centers now perform peripheral endovascular intervention (PVI) as the first-line treatment for these patients. We sought to determine the effect of a prior ipsilateral PVI (iPVI) on the outcome of subsequent lower extremity bypass (LEB) in patients with CLI.

METHODS

A retrospective cohort analysis of all patients undergoing infrainguinal LEB between 2003 and 2009 within hospitals comprising the Vascular Study Group of New England (VSGNE) was performed. Primary study endpoints were major amputation and graft occlusion at 1 year postoperatively. Secondary outcomes included in-hospital major adverse events (MAE), 1-year mortality, and composite 1-year major adverse limb events (MALE). Event rates were determined using life table analyses and comparisons were performed using the log-rank test. Multivariate predictors were determined using a Cox proportional hazards model with multilevel hierarchical adjustment.

RESULTS

Of 1880 LEBs performed, 32% (n = 603) had a prior infrainguinal revascularization procedure (iPVI, 7%; ipsilateral bypass, 15%; contralateral PVI, 3%; contralateral bypass, 17%). Patients with prior iPVI, compared with those without a prior iPVI, were more likely to be women (32 vs 41%; P = .04), less likely to have tissue loss (52% vs 63%; P = .02), more likely to require arm vein conduit (16% vs 5%; P = .001), and more likely to be on statin (71% vs 54%; P = .01) and beta blocker therapy (92% vs 81%; P = .01) at the time of their bypass procedure. Other demographic factors were similar between these groups. Prior PVI or bypass did not alter 30-day MAE and 1-year mortality after the index bypass. In contrast, 1-year major amputation and 1-year graft occlusion rates were significantly higher in patients who had prior iPVI than those without (31% vs 20%; P = .046 and 28% vs 18%; P = .009), similar to patients who had a prior ipsilateral bypass (1 year major amputation, 29% vs 20%; P = .022; 1 year graft occlusion, 33% vs 18%; P = .001). Independent multivariate predictors of higher 1-year amputation and graft occlusion rates were prior iPVI, prior ipsilateral bypass, dialysis dependence, prosthetic conduit and distal (tibial and pedal) bypass target.

CONCLUSIONS

Prior iPVI is highly predictive for poor outcome in patients undergoing LEB for CLI with higher 1-year amputation and graft occlusion rates than those without prior revascularization, similar to prior ipsilateral bypass These findings provide information, which may help with the complex decisions surrounding revascularization options in patients with CLI.

National trends and regional variation of open and endovascular repair of thoracic and thoracoabdominal aneurysms in contemporary practice

OBJECTIVES

Successful surgical management of thoracic aortic aneurysms (TAA) and thoracoabdominal aortic aneurysms (TAAA) has historically relied upon open surgical repair (OSR). More recently, the advent and application of thoracic endovascular stent graft aneurysm repair (TEVAR) permutations have become increasingly performed in contemporary practice. To better determine the effect of TEVAR techniques on OSR, we examined national and regional trends in treatment use.

METHODS

All Medicare patients from 1998 through 2007 undergoing isolated TAA and TAAA repair were analyzed using a clinically validated algorithm using diagnostic International Classification of Disease 9th revision (ICD-9; 441.1, 441.2, 441.6, 441.7, 441.9) codes and procedural (ICD-9 OSR: 38.35, 38.45 and TEVAR: 39.73, 39.79) codes. Differential rates of OSR and TEVAR were compared across census tract regions during the study interval.

RESULTS

Total complex aortic repairs increased by 60%, from 10.8 to 17.8/100,000, between 1998 and 2007 (P < .001). A dramatic increase occurred in TEVAR (not performed in 1998, 5.8/100,000 in 2007) during the study period, but OSR rates remained stable during the same interval (10.7 to 12.0/100,000 in 2007, P = NS). There was substantial regional variation for both OSR and TEVAR. This regional variation was greater in OSR (range, 8.8-16.7/100,000) than in TEVAR (range, 4.5-6.9/100,000).

CONCLUSIONS

Degenerative TAA and TAAA aneurysms are being repaired in the United States at an increasing rate. This reflects the rapid acceptance of TEVAR, which apparently supplements rather than supplants OSR. There appears to be greater regional variation in OSR compared with TEVAR. These data may have significant implications for those interested in the effect of new technologies on health care and cost containment.