A systematic review of the effect of surgeon and hospital volume on survival in aortic, thoracic and fenestrated endovascular aneurysm repair

BACKGROUND

Endovascular aneurysm repair (EVAR) is becoming a mainstay in vascular surgery, both in metropolitan and regional hospitals. This review aims to assess the impact of hospital and surgeon volume on perioperative mortality specific to this surgery type to support the use of this treatment modality extensively.

METHODS

A literature search was performed on multiple dedicated medical databases using a detailed search strategy with terms focusing on hospital volume and EVARs. Inclusion and exclusion criteria were used to screen and evaluate suitable sources, focusing on operators and hospitals performing EVARs and the morbidity/mortality as outcomes. The results were then appraised using a PRISMA framework.

RESULTS

We reviewed 45 articles. Twelve articles met inclusion criteria for complete review. There was no level 1 evidence, and only a single systematic review and meta-analysis. EVAR and thoracic EVAR perioperative mortality had no correlation with hospital volume. Limited evidence was presented for fenestrated EVAR, where a mortality risk based on hospital volume remains unanswered. Open procedures for aneurysm repair had perioperative mortality outcomes that grossly correlated with hospital volume, supporting their use in high-volume centers.

CONCLUSIONS

With open aneurysm repairs having an increased mortality risk in low-volume centers, and endovascular treatment options gaining momentum, there is considerable support for the use of EVAR and thoracic EVAR in smaller regional centers safely and effectively. There is very limited evidence in the use of fenestrated EVAR, which remains unanswered, but presents a significant opportunity for research.

Contemporary Practices and Complications of Surgery for Thoracic Outlet Syndrome in the United States

BACKGROUND

Thoracic outlet syndrome (TOS) surgery is relatively rare and controversial, given the challenges in diagnosis as well as wide variation in symptomatic and functional recovery. Our aims were to measure trends in utilization of TOS surgery, complications, and mortality rates in a nationally representative cohort and compare higher versus lower volume centers.

METHODS

The National Inpatient Sample was queried using International Classification of Diseases, Ninth Revision, codes for rib resection and scalenectomy paired with axillo-subclavian aneurysm (arterial [aTOS]), subclavian deep vein thrombosis (venous [vTOS]), or brachial plexus lesions (neurogenic [nTOS]). Basic descriptive statistics, nonparametric tests for trend, and multivariable hierarchical regression models with random intercept for center were used to compare outcomes for TOS types, trends over time, and higher and lower volume hospitals, respectively.

RESULTS

There were 3,547 TOS operations (for an estimated 18,210 TOS operations nationally) performed between 2010 and 2015 (89.2% nTOS, 9.9% vTOS, and 0.9% aTOS) with annual case volume increasing significantly over time (P = 0.03). Higher volume centers (≥10 cases per year) represented 5.2% of hospitals and 37.0% of cases, and these centers achieved significantly lower overall major complication (defined as neurologic injury, arterial or venous injury, vascular graft complication, pneumothorax, hemorrhage/hematoma, or lymphatic leak) rates (adjusted odds ratio [OR] 0.71 [95% confidence interval 0.52-0.98]; P = 0.04], but no difference in neurologic complications such as brachial plexus injury (aOR 0.69 [0.20-2.43]; P = 0.56) or vascular injuries/graft complications (aOR 0.71 [0.0.33-1.54]; P = 0.39). Overall mortality was 0.6%, neurologic injury was rare (0.3%), and the proportion of patients experiencing complications decreased over time (P = 0.03). However, vTOS and aTOS had >2.5 times the odds of major complication compared with nTOS (OR 2.68 [1.88-3.82] and aOR 4.26 [1.78-10.17]; P < 0.001), and ∼10 times the odds of a vascular complication (aOR 10.37 [5.33-20.19] and aOR 12.93 [3.54-47.37]; P < 0.001], respectively. As the number of complications decreased, average hospital charges also significantly decreased over time (P < 0.001). Total hospital charges were on average higher when surgery was performed in lower volume centers (<10 cases per year) compared with higher volume centers (mean $65,634 [standard deviation 98,796] vs. $45,850 [59,285]; P < 0.001).

CONCLUSIONS

The annual number of TOS operations has increased in the United States from 2010 to 2015, whereas complications and average hospital charges have decreased. Mortality and neurologic injury remain rare. Higher volume centers delivered higher value care: less or similar operative morbidity with lower total hospital charges.

Improved outcomes of endovascular repair of thoracic aortic injuries at higher volume institutions

BACKGROUND

The use of thoracic endovascular aortic repair (TEVAR) has significantly improved the ability to treat traumatic aortic injuries (tTEVAR). We sought to determine whether a greater center volume correlated with better outcomes.

METHODS

Vascular Quality Initiative data of TEVAR (2011-2017) for trauma were used in the present analysis. Using the distribution of the annual case volume at the participating centers, the sample was stratified into three terciles. In-hospital mortality at high-volume centers (HVCs) and low-volume centers (LVCs) was compared after adjustment for risk factors established in our previous Vascular Quality Initiative-based risk model containing age, gender, renal impairment, left subclavian artery involvement, and select concomitant injuries.

RESULTS

A total of 619 tTEVAR cases were studied across 74 centers. HVCs (n = 184 cases) had performed ≥4.9 cases annually and LVCs (n = 220 cases) had performed ≤2.4 cases annually. Both crude mortality (4.4% vs 8.6%; P = .22) and adjusted odds of mortality (odds ratio, 0.44; 95% confidence interval, 0.18-1.09; P = .08) showed a trend toward better outcomes for tTEVAR performed at HVCs than at LVCs. The addition of center volume to our previous multivariate model significantly improved its discriminative ability (C-statistic, 0.90 vs 0.88; P = .02). The overall TEVAR volume (for all indications) was not associated with increased odds of mortality for tTEVAR (odds ratio, 0.46; 95% confidence interval, 0.17-1.20; P = .11), nor did it improve the model's discriminative ability.

CONCLUSIONS

Higher volume centers showed improved perioperative mortality after tTEVAR. The thoracic aortic trauma volume was more predictive than the overall TEVAR volume, suggesting that technical expertise is not the driving factor. Stable patients might benefit from transfer to a higher volume center before repair.

Procedural Volume and Outcomes After Percutaneous Coronary Intervention for Unprotected Left Main Coronary Artery Disease-Report From the National Clinical Data (J-PCI Registry)

Background There is a limited evidence base to support the volume-outcome relationship in patients undergoing percutaneous coronary intervention (PCI) for unprotected left main coronary artery disease (UPLMD). This study aimed to evaluate the relationship between institutional and operator volume and in-hospital outcomes in patients undergoing PCI for unprotected left main coronary artery disease. Methods and Results We analyzed characteristics and clinical outcomes of 24 320 patients undergoing PCI for unprotected left main coronary artery disease at 1102 hospitals by 7244 operators using data from the Japanese nationwide J-PCI Registry (National PCI Data Registry) between January 2014 and December 2017. We classified institutions and operators into quartiles based on the mean annual volume of PCI. A generalized linear mixed-effects model was used to evaluate the association between institutional and operator PCI volume and in-hospital outcomes. Among the 24 320 patients, 4027 (16.6%), 6147 (25.3%), and 14 146 (58.2%) presented with ST-segment-elevation myocardial infarction, non-ST-segment-elevation acute coronary syndrome, and stable ischemic heart disease; their crude in-hospital mortality was 15%, 3.1%, and 0.3%, respectively. Compared with patients in the lowest quartile of institutional volume (1-216 PCIs/y), the adjusted odds ratio of in-hospital death in patients in the second (217-323 PCIs/y), third (324-487 PCIs/y), and fourth (488-3015 PCIs/y) quartile of institutional volume was 0.75 (95% CI, 0.51-1.10; P=0.14), 0.87 (95% CI, 0.57-1.34; P=0.54), and 0.51 (95% CI, 0.30-0.86; P=0.01), respectively. These findings were consistent in rates of in-hospital death or any complication. Conversely, operator PCI volume was not significantly associated with in-hospital outcomes. Conclusions Institutional rather than operator-based PCI volume was associated with better in-hospital outcomes in patients undergoing PCI for unprotected left main coronary artery disease.

Ninety day mortality following pancreatoduodenectomy in England: has the optimum centre volume been identified?

BACKGROUND

Mortality following pancreatoduodenectomy is related to centre volume although the optimal volume is not defined.

METHODS

Patients undergoing PD between 2001 and 2016 were identified from UK national databases. The effects of patient variables, centre volume and time period upon 90 day mortality were studied.

RESULTS

90 day mortality (970/14,935, 6.5%) was related to advanced age, comorbidity, diagnosis, ethnicity, deprivation, centre volume and time period. Mortality rates fell markedly from 10.0% in 2001-4 to 4.1% in 2013-16. There was no difference in 90 day mortality between high (36 -60 PD per year) and very high volume (>60) centres. However, patients operated upon at very high volume centres were more elderly (66, 58 -73 vs 65, 56 -72; median, IQR; p = 0.006), deprived (38.7 vs 34.6%; p < 0.001) and co morbid (48.9 vs 46.1%; p = 0.027).

CONCLUSION

Although a plateau in the centre volume and mortality relationship appears to have been demonstrated those patients treated at the highest volume centres were at higher risk of mortality. This data suggests therefore that to further understand outcomes from specialist centres characteristics of the patient population should be defined, not just centre volume.

An Operative Complexity Index Shows Higher Volume Hospitals and Surgeons Perform More Complex Adult Spine Deformity Operations

BACKGROUND

Though previous studies have shown improved outcomes associated with higher volume surgeons and hospitals, this may not be replicated in ASDS due to case complexity variation. We hypothesized that high-volume surgeons perform more complex surgeries. Therefore, we defined an Operative Complexity Index (OCI), specifically for the National Inpatient Samples (NIS) data, which provides information on in-hospital postoperative complications, to assess rates of adult spine deformity surgery (ASDS) cases as they relate to surgeon and hospital operative volume.

METHODS

The 2001 to 2010 NIS was queried for patients greater than 21 years of age with in-hospital stays, including a spine arthrodesis for a diagnosis of scoliosis. Surgeon and hospital identifiers were used to allocate records into volume quartiles by number of surgeries per year. The OCI was devised considering the number of fusion levels, surgical approach, revision status, and use of osteotomy. The index was validated using blood-loss-related diagnostic and procedural codes. One-way ANOVA assessed continuous measures. Chi-square assessed categorical measures.

RESULTS

141,357 ASDS cases met the inclusion criteria. High-volume surgeons performed a higher rate of longfusions (> 8 levels), revision surgeries, and surgeries requiring osteotomy. The OCI showed weak, but significant, correlation with blood loss values: acute blood loss anemia (r = 0.21) and treatment with blood products (r = 0.12) (p < 0.001). High OCI also was also associated with increased length of stay (r = 0.27) and total charges (r = 0.41) (p < 0.001).

CONCLUSIONS

The operative complexity index (OCI) for ASDS increases with high-volume surgeons and centers, indicating it can be useful to adjust for surgical invasiveness in the NIS database. Operative complexity must be considered when evaluating patient safety and quality indices among hospitals and surgeons.

The Centralization of Total Joint Arthroplasty in New York State An Analysis of 168,247 Cases

We identified 168,247 total hip and total knee arthroplasties performed in New York State between 2010 and 2012 to examine the evidence for increased geographical and institutional centralization of these procedures. We measured the increased growth of high volume institutions as compared to lower volume hospitals in New York State. We found a high proportion of total arthroplasties already performed in the dozen biggest hospitals in New York back in 2010 and a significant higher growth of these high volume, "centers of excellence," hospitals when compared to low volume hospitals.

Worldwide practice in gastric cancer surgery

AIM: To evaluate the current status of gastric cancer surgery worldwide.

METHODS: An international cross-sectional survey on gastric cancer surgery was performed amongst international upper gastro-intestinal surgeons. All surgical members of the International Gastric Cancer Association were invited by e-mail to participate. An English web-based survey had to be filled in with regard to their surgical preferences. Questions asked included hospital volume, the use of neoadjuvant treatment, preferred surgical approach, extent of the lymphadenectomy and preferred anastomotic technique. The invitations were sent in September 2013 and the survey was closed in January 2014.

RESULTS: The corresponding specific response rate was 227/615 (37%). The majority of respondents: originated from Asia (54%), performed > 21 gastrectomies per year (79%) and used neoadjuvant chemotherapy (73%). An open surgical procedure was performed by the majority of surgeons for distal gastrectomy for advanced cancer (91%) and total gastrectomy for both early and advanced cancer (52% and 94%). A minimally invasive procedure was preferred for distal gastrectomy for early cancer (65%). In Asia surgeons preferred a minimally invasive procedure for total gastrectomy for early cancer also (63%). A D1+ lymphadenectomy was preferred in early gastric cancer (52% for distal, 54% for total gastrectomy) and a D2 lymphadenectomy was preferred in advanced gastric cancer (93% for distal, 92% for total gastrectomy)

CONCLUSION: Surgical preferences for gastric cancer surgery vary between surgeons worldwide. Although the majority of surgeons use neoadjuvant chemotherapy, minimally invasive techniques are still not widely adapted.

Stage 1 hybrid palliation for hypoplastic left heart syndrome--assessment of contemporary patterns of use: an analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

OBJECTIVE

Hybrid palliation is an alternative to Norwood stage 1 for the initial management of hypoplastic left heart syndrome. Contemporary multicenter hybrid use and institutional/patient factors associated with hybrid use relative to the Norwood have not been evaluated. We describe hybrid use in relation to institutional volume, patient factors, and short-term outcomes.

METHODS

Infants aged 60 days or less listed in The Society of Thoracic Surgeons Congenital Heart Surgery Database (2010-2012) undergoing initial palliation of hypoplastic left heart syndrome were included. Annual institutional hybrid use rates were calculated: [hybrid procedures/(Norwood + hybrid + transplant procedures)]. In-hospital outcomes for primary hybrid and primary Norwood were compared and stratified by high (defined as ≥50%) versus low (defined as ≤10%) institutional hybrid use.

RESULTS

Of 1728 patients (100 centers), most (n = 1496, 87%) underwent an index Norwood; 232 patients (13%) underwent an index hybrid procedure. Preoperative patient risk factors were more prevalent in patients undergoing the hybrid procedure. Only 13 of 100 institutions were high hybrid users, and these tended to have lower annual hypoplastic left heart syndrome index case volume. Unadjusted in-hospital mortality was higher for the hybrid compared with the Norwood procedure (30% vs 16%; P < .001). In-hospital mortality for the hybrid procedure was not associated with hybrid use (26% among institutions with low use vs 28% among institutions with high use). However, centers with high hybrid use had higher mortality after the Norwood (43%) compared with centers with low hybrid use (16%).

CONCLUSIONS

Few centers currently select the hybrid procedure for most infants with hypoplastic left heart syndrome. Although unadjusted in-hospital hybrid mortality is higher than Norwood mortality, potential risk factors are more prevalent among hybrid cases. Institutions with higher hybrid use have lower hypoplastic left heart syndrome case volume and higher Norwood mortality.

Influence of high- and low-volume liver surgery in gallbladder carcinoma

AIM: To clarify whether the performance of liver resections (LR) for incidental gallbladder carcinoma (IGBC)’s depends more on the experience of the hospitals in liver surgery than on complying with the guidelines in Germany.

METHODS: For data analysis, we used the Surgical Association of Endoscopy and Ultrasound and Minimally Invasive Surgery Central Registry of “IGBC” of the German Society of Surgery (the German Registry). In 2010, we started a second form by requesting the frequency of LR at the various hospitals in Germany. The indication for LR was irrelevant. The aim was to determine the overall frequency of liver resections at the hospitals. We divided the hospitals according to their experience in liver surgery into high- (HV), mid- (MV), and low-volume (LV) LR hospitals.

RESULTS: This study includes 487 IGBC’s from 167 centers. There were 36 high-volume, 32 mid-volume, and 99 low-volume centers. In the high-volume centers, the mean (range) number of liver resections was 101 (40-300). In the mid-volume centers, the mean (range) number of liver resections was 26 (20-39). In the low-volume centers, the mean (range) number of liver resections was 6.5 (0-19) (P < 0.001). LV’s perform LR for T2-3 gallbladder carcinomas significantly less often than high-volume or mid-volume centers (χ² = 13.78, P = 0.001). In HV’s and MV’s, 61% of the patients with an indication for liver resection underwent LR, but in LV centers, only 41% with an indication for LR underwent LR (P < 0.001). In cases of T1b carcinomas, LR was performed significantly more often in HV’s (P = 0.009).

CONCLUSION: The central problem is that the performance of the required liver resection in IGBC in Germany depends on the hospital experience in liver surgery and not on the recommendations of the German guidelines.

First 100 cases at a low volume prostate brachytherapy institution: learning curve and the importance of continuous quality improvement

INTRODUCTION

We report the first 100 patients who underwent prostate brachytherapy as monotherapy with 125I at an institution with moderate volume radical prostatectomy but low volume brachytherapy (<2 cases per month). Learning curve and quality improvement was assessed by way of achieving prescription dose targets.

MATERIALS AND METHODS

From May 2002 to August 2006, 100 patients underwent prostate 125I brachytherapy monotherapy via preplanned approach. Preoperative planned dose to 100% of prostate gland (D100) was 145 Gy and postoperative confirmed dose was assessed by computed tomography. The cohort was divided into quartiles and recurrence was assessed using Kaplan-Meier analysis.

RESULTS

Patient quartiles were of similar age and Gleason grade, while PSA was slightly higher in the first group. Postoperative D90 increased after the first quartile (p = < 0.0001) reaching targeted values. Kaplan-Meier survival analysis revealed that 5 year recurrence-free survivals by Phoenix definition was 96%-100% in all groups while by ASTRO definition there was a decrease in recurrence for later cases.

CONCLUSIONS

At our low volume institution during the first 100 brachytherapy cases, a learning curve for radiation dosimetry was evident, which improved after 25 patients. Preplanned dose-volume parameters were adjusted, enabling the achievement of post-implant goals emphasizing the importance of continuous quality improvement. Although recurrence data is limited by sample size and moderate follow up, there was a discrepancy between the Phoenix and ASTRO definition when evaluating recurrence.