OBJECTIVE: The objective of the present study was to model the effects of a reduced number of treatment centres for acute type A aortic dissection on preclinical transportation distance and time. We examined whether treatment in selected centres in Germany would be implementable with respect to time to treatment.
METHODS: For our transportation model, the number of aortic dissections and respective mean annual volume were collected from the annual quality reports (2015-2017) of all German cardiac surgery centres (n = 76). For each German postal code, the fastest and shortest routes to the nearest centre were calculated using Google Maps. Furthermore, we analysed data from the German Federal Statistical Office from January 2005 to December 2015 to identify all surgically treated patients with acute type A aortic dissection (n = 14 102) and examined the relationship between in-hospital mortality and mean annual volume of medical centres.
RESULTS: Our simulation showed a median transportation distance of 27.13 km and transportation time of 35.78 min for 76 centres. Doubling the transportation time (70 min) would allow providing appropriate care with only 12 medical centres. Therefore, a mean annual volume of >25 should be obtained. High mean annual volume was associated with significantly lower in-hospital mortality rates (P < 0.001). A significantly lower mortality rate of 14% was observed (P < 0.001) if a mean annual volume of 30 was achieved.
CONCLUSIONS: Operationalizing the volume-outcome relationship with fewer but larger medical centres results in lower mortality, which outweighs the disadvantage of longer transportation time.

BACKGROUND: Hirschsprung\'s disease (HD) is a rare and complex malformation. The corrective operation is challenging and schedulable. The complete care situation for the corrective surgery for HD in Germany is uninvestigated.
METHODS: For the years 2016-2022, the microdata of the diagnosis-related groups (DRG) -statistics provided by the Research Data Center of the German Federal Statistical Office were accessed. All hospital stays for corrective surgery of HD in patients aged 0-17 were analyzed for patient\'s comorbidities, treatment characteristics and hospital structures. The occurrence of severe early postoperative complications during the hospital stay were documented.
RESULTS: The care structure for HD in Germany is decentralized with 109 hospitals performing 1199 corrective surgeries in 7 years. 75% of the participating hospitals performed three or less cases per year and 55 participating hospitals did not perform corrective surgery for HD each year. Early postoperative complications were common with at least one severe early complication in 18.6% of the cases. With an overall low case load per hospital, a volume outcome relationship cannot be established within Germany. Compared to international high volume centers the quality of outcomes for some of the investigated parameters was reduced. Despite the establishing of centers of expertise by the European reference network ERNICA for the treatment of HD no trend towards centralization occurred in Germany.
CONCLUSIONS: The corrective surgery for HD in Germany is decentralized and results in an overall high rate of early complications. The comparison with international studies from high-volume centers indicates potential for improvement for the corrective surgery of HD. Centralization remains essential for the improvement of care for patients with HD.

Acute myocardial infarction (MI) is one of the major scenarios of extracorporeal membrane oxygenation (ECMO) use. The utilization of mechanical circulatory support systems including ECMO varies widely at the hospital level, while whether ECMO volume per hospital is associated with outcomes in acute MI is unclear. Using a Japanese nationwide administrative database, a total of 26,913 patients with acute MI undergoing percutaneous coronary intervention from 154 hospitals were included. The relations among PCI volume for acute MI, observed and predicted in-hospital mortality, and observed and predicted rates of ECMO use were evaluated at the hospital level. Of 26,913 patients, 423 (1.6%) were treated with ECMO, and 1561 (5.8%) died during the hospitalization. Median ECMO use per hospital per year was 0.5. An observed rate of ECMO use was linearly correlated with the predicted probability of ECMO use and was not associated with the observed/predicted in-hospital mortality ratio. The observed/predicted mortality ratio was lowest in hospitals with the observed/predicted ECMO use ratio of around one. In conclusion, ECMO was infrequently used in a setting of acute MI at each hospital annually. An observed rate of ECMO use was not associated with observed/predicted in-hospital mortality ratio, while the observed/predicted in-hospital mortality ratio was lowest when ECMO was used as predicted, suggesting that standardized ECMO use may be an institutional quality indicator in acute MI.

The current study proposes a novel volume-outcome (V-O) meta-analytical approach to determine the optimal annual hospital case volume threshold for cardiovascular interventions in need of centralization. This novel method is applied to surgery for acute type A aortic dissection (ATAAD) as an illustrative example.
A systematic search was applied to three electronic databases (1 January 2012 to 29 March 2023). The primary outcome was early mortality in relation to annual hospital case volume. Data were presented by volume quartiles (Qs). Restricted cubic splines were used to demonstrate the V-O relation, and the elbow method was applied to determine the optimal case volume. For clinical interpretation, numbers needed to treat (NNTs) were calculated.
One hundred and forty studies were included, comprising 38 276 patients. A significant non-linear V-O effect was observed (P < .001), with a notable between-quartile difference in early mortality rate [10.3% (Q4) vs. 16.2% (Q1)]. The optimal annual case volume was determined at 38 cases/year [95% confidence interval (CI) 37-40 cases/year, NNT to save a life in a centre with the optimal volume vs. 10 cases/year = 21]. More pronounced between-quartile survival differences were observed for long-term survival [10-year survival (Q4) 69% vs. (Q1) 51%, P < .01, adjusted hazard ratio 0.83, 95% CI 0.75-0.91 per quartile, NNT to save a life in a high-volume (Q4) vs. low-volume centre (Q1) = 6].
Using this novel approach, the optimal hospital case volume threshold was statistically determined. Centralization of ATAAD care to high-volume centres may lead to improved outcomes. This method can be applied to various other cardiovascular procedures requiring centralization.

BACKGROUND: Hip arthroplasty is a frequently performed procedure in orthopedic surgery, carried out in almost all health structures for two main issues: fracture and coxarthrosis. Even if volume-outcome relationship appeared associated in many surgeries recently, data provided are not sufficient to set surgical thresholds neither than closing down low-volumes centers.
OBJECTIVE: With this study, we wanted to identify surgical, health care-related and territorial factors influencing patient\' mortality and readmission after a HA for a femoral fracture in 2018 in France.
METHODS: Data were anonymously collected from French nationwide administrative databases. All patients who underwent a hip arthroplasty for a femoral fracture through 2018 were included. Patient outcome was 90-day mortality and 90-day readmission rate after surgery.
RESULTS: Of the 36,252 patients that underwent a HA for fracture in France in 2018, 0.7% died within 90-day year and 1.2% were readmitted. Male and Charlson comorbidity index were associated with a higher 90-day mortality and readmission rate in multivariate analysis. High volume was associated with a lower mortality rate. Neither time of travel nor distance upon health facility were associated with mortality nor with readmission rate in the analysis.
CONCLUSIONS: Even if volume appears to be associated with lower mortality rate even for longer distance and time of travel, the persistence of exogenous factors not documented in the French databases suggests that regionalization of hip arthroplasty should be organized with caution.
CONCLUSIONS: As volume-outcome relationship must be interpreted with caution, policy makers should not regionalize such surgery without further investigation.

OBJECTIVE: Adrenal resections are rare procedures of a heterogeneous nature. While recent European guidelines advocate a minimum annual caseload for adrenalectomies (6 per surgeon), evidence for a volume-outcome relationship for this surgery remains limited.
METHODS: A retrospective analysis of all adrenal resections in Germany between 2009 and 2017 using hospital billing data was performed. Hospitals were grouped into three tertiles of approximately equal patient volume.
METHODS: Descriptive, univariate, and multivariate analyses were applied to identify a possible volume-outcome relationship (complications, complication management, and mortality).
RESULTS: Around 17 040 primary adrenal resections were included. Benign adrenal tumors (n = 8,213, 48.2%) and adrenal metastases of extra-adrenal malignancies (n = 3582, 21.0%) were the most common diagnoses. Six hundred and thirty-two low-volume hospitals performed an equal number of resections as 23 high-volume hospitals (median surgeries/hospital/year 3 versus 31, P < .001). Complications were less frequent in high-volume hospitals (23.1% in low-volume hospitals versus 17.3% in high-volume hospitals, P < .001). The most common complication was bleeding in 2027 cases (11.9%) with a mortality of 4.6% (94 patients). Overall in-house mortality was 0.7% (n = 126). Age, malignancy, an accompanying resection, complications, and open surgery were associated with in-house mortality. In univariate analysis, surgery in high-volume hospitals was associated with lower mortality (OR: 0.47, P < .001). In a multivariate model, the tendency remained equal (OR: 0.59, P = .104). Regarding failure to rescue (death in case of complications), there was a trend toward lower mortality in high-volume hospitals.
CONCLUSIONS: The annual caseload of adrenal resections varies considerably among German hospitals. Our findings suggest that surgery in high-volume centers is advantageous for patient outcomes although fatal complications are rare.

This study examined the effect of hospital surgical volume on oncologic outcomes in minimally invasive surgery (MIS) for gynecologic malignancies. The objectives were to assess survival outcomes related to hospital surgical volume and to evaluate perioperative outcomes and examine non-gynecologic malignancies. Literature available from the PubMed, Scopus, and the Cochrane Library databases were systematically reviewed. All surgical procedures including gynecologic surgery with hospital surgical volume information were eligible for analysis. Twenty-three studies met the inclusion criteria, and nine gastro-intestinal studies, seven genitourinary studies, four gynecological studies, two hepatobiliary studies, and one thoracic study were reviewed. Of those, 11 showed a positive volume-outcome association for perioperative outcomes. A study on MIS for ovarian cancer reported lower surgical morbidity in high-volume centers. Two studies were on endometrial cancer, of which one showed lower treatment costs in high-volume centers and the other showed no association with perioperative morbidity. Another study examined robotic-assisted radical hysterectomy for cervical cancer and found no volume-outcome association for surgical morbidity. There were no gynecologic studies examining the association between hospital surgical volume and oncologic outcomes in MIS. The volume-outcome association for oncologic outcome in gynecologic MIS is understudied. This lack of evidence calls for further studies to address this knowledge gap.

UNASSIGNED: Operability of type A acute aortic dissections (TAAAD) is currently based on non-standardized decision-making process, and it lacks a disease-specific risk evaluation model that can predict mortality. We investigated patient, intraoperative data, surgeon, and centre-related variables for patients who underwent TAAAD in the UK.
RESULTS: We identified 4203 patients undergoing TAAAD surgery in the UK (2009-18), who were enrolled into the UK National Adult Cardiac Surgical Audit dataset. The primary outcome was operative mortality. A multivariable logistic regression analysis was performed with fast backward elimination of variables and the bootstrap-based optimism-correction was adopted to assess model performance. Variation related to hospital or surgeon effects were quantified by a generalized mixed linear model and risk-adjusted funnel plots by displaying the individual standardized mortality ratio against expected deaths. Final variables retained in the model were: age [odds ratio (OR) 1.02, 95% confidence interval (CI) 1.02-1.03; P < 0.001]; malperfusion (OR 1.79, 95% CI 1.51-2.12; P < 0.001); left ventricular ejection fraction (moderate: OR 1.40, 95% CI 1.14-1.71; P = 0.001; poor: OR 2.83, 95% CI 1.90-4.21; P < 0.001); previous cardiac surgery (OR 2.29, 95% CI 1.71-3.07; P < 0.001); preoperative mechanical ventilation (OR 2.76, 95% CI 2.00-3.80; P < 0.001); preoperative resuscitation (OR 3.36, 95% CI 1.14-9.87; P = 0.028); and concomitant coronary artery bypass grafting (OR 2.29, 95% CI 1.86-2.83; P < 0.001). We found a significant inverse relationship between surgeons but not centre annual volume with outcomes.
UNASSIGNED: Patient characteristics, intraoperative factors, cardiac centre, and high-volume surgeons are strong determinants of outcomes following TAAAD surgery. These findings may help refining clinical decision-making, supporting patient counselling and be used by policy makers for quality assurance and service provision improvement.

Appropriate trauma care systems, suitable for children are needed; thus, this retrospective nationwide study evaluated the correlation between the annual total hospital volume of severely injured patients and in-hospital mortality of severely injured pediatric patients (SIPP) and compared clinical parameters and outcomes per hospital between low- and high-volume hospitals. During the five-year study period, we enrolled 53,088 severely injured patients (Injury Severity Score, ≥16); 2889 (5.4%) were pediatric patients aged <18 years. Significant Spearman correlation analysis was observed between numbers of total patients and SIPP per hospital (p < 0.001), and the number of SIPP per hospital who underwent interhospital transportation and/or urgent treatment was correlated with the total number of severely injured patients per hospital. Actual in-hospital mortality, per hospital, of SIPP patients was significantly correlated with the total number patients per hospital (p < 0.001,). The total number of SIPP, requiring urgent treatment, was higher in the high-volume than in the low-volume hospital group. No significant differences in actual in-hospital morality (p = 0.246, 2.13 (0-8.33) vs. 0 (0-100)) and standardized mortality ratio (SMR) values (p = 0.244, 0.31 (0-0.79) vs. 0 (0-4.87)) were observed between the two groups; however, the 13 high-volume hospitals had an SMR of <1.0. Centralizing severely injured patients, regardless of age, to a higher volume hospital might contribute to survival benefits of SIPP.

OBJECTIVE: Volume concentration of complex noncardiac operations to high-volume centers has been observed, but whether this is also occurring in cardiac surgery is unknown. We examined the relationship between volume concentration and mortality rates for valve surgery and coronary artery bypass grafting (CABG) between 2005 and 2016 in New York State.
METHODS: We analyzed publicly available, hospital-level case volume and risk-adjusted mortality rates (RAMRs) from 2005 to 2016 for isolated CABG and isolated or concomitant valve operations performed in New York. We identified hospitals in the top- and bottom-volume quartiles for each procedure type and compared changes in percent market share and outcomes. Bivariate and univariate longitudinal analysis was used to evaluate the statistical significance of the temporal trend.
RESULTS: Among 36 centers, percent market share of the top-volume quartile increased for valve cases from 54.4% to 59.4%, whereas CABG share increased from 41.4% to 44.3%. No significant changes were noted in market share for the bottom quartile. The top-volume quartile demonstrated significant trends in improving outcomes over the study period for both valve procedures (RAMR: -0.261%/year, P < .001) and CABG (RAMR: -0.071%/year, P = .018). No significant trends were noted in the bottom quartile for either procedure.
CONCLUSIONS: In New York, over the last decade, highest-volume hospitals increased their market share for valve operations while maintaining lower mortality rates than lowest-volume hospitals. Valve volume is regionalizing in the setting of a persistent outcome gap between the highest- and lowest-volume hospitals, suggesting that volume-based referrals for specialized cardiac procedures may improve surgical mortality.