Survival does not differ by annual center transplant volume-A Pediatric Heart Transplant Society Registry study.

BACKGROUND: There are conflicting data regarding the relationship between center volume and outcomes in pediatric heart transplantation. Previous studies have not fully accounted for differences in case mix, particularly in high-risk congenital heart disease (CHD) groups. We aimed to evaluate the relationship between center volume and outcomes using the Pediatric Heart Transplant Society (PHTS) Registry and explore how case mix may affect outcomes. METHODS: A retrospective cohort study of all pediatric patients in the PHTS Registry who received a heart transplant from 2009 to 2018 was performed. Centers were divided into 5 groups based on average yearly transplant volume. The primary outcome was time to death or graft loss and outcomes were compared using Kaplan-Meier analysis. RESULTS: There were 4583 cases among 55 centers included. There was no difference in time to death or graft loss by center volume in the entire cohort (p = .75), in patients with CHD (p = .79) or in patients with cardiomyopathy (p = .23). There was also no difference in time to death or graft loss by center size in patients undergoing transplant after Norwood, Glenn or Fontan (log rank p = .17, p = .31, and p = .10 respectively). There was a statistically significant difference in outcomes by center size in the positive crossmatch group (p < .0001), though no discernible pattern related to high or low center volume. CONCLUSIONS: Outcomes are similar among transplant centers of all sizes, including for high-risk patient groups with CHD. Future work is needed to understand how patient-specific risk factors may vary among centers of various sizes and whether this influences patient outcomes.

Size matters: Influence of center size on quality of diabetes control in children and adolescents with type 1 diabetes-A longitudinal analysis of the DPV cohort.

BACKGROUND: Treatment of patients with type 1 diabetes requires experience and a specific infrastructure. Therefore, center size might influence outcome in diabetes treatment. OBJECTIVE: To analyze the influence of center size on the quality of diabetes treatment in children and adolescents in Germany and Austria. PATIENTS AND METHODS: In 2009 and 2018, we analyzed metabolic control, acute complications, and rates of recommended screening tests in the DPV cohort. Diabetes centers were classified according to the number of patients from "XS" to "XL" (<20 [XS], ≥20 to <50 [S], ≥50 to <100 [M], ≥100 to <200 [L], ≥200 [XL]). RESULTS: Over the 10-year period, metabolic control improved significantly in "M", "L" and "XL" diabetes centers. Treatment targets are best achieved in "M" centers, while "XS" centers have the highest mean hemoglobin A1c. The relation between hemoglobin A1c and center size follows a "v-shaped" curve. In 2009, conventional insulin therapy was most frequently used in "XS" centers, but in 2018, there was no difference in mode of insulin therapy according to center size. Use of CSII and sensor augmented CSII/hybrid closed loop increased with center size. Patients cared for in "XS" diabetes centers had the fewest follow-up visits per year. The rates of severe hypoglycemia and DKA were lowest in "XL" diabetes centers, and the rate of DKA was highest in "XS" centers. CONCLUSION: Center size influences quality of care in pediatric patients with type 1 diabetes. Further investigations regarding contributing factors such as staffing and financial resources are required.

Annual hospital procedural volume and outcome in extracorporeal membrane oxygenation for respiratory failure.

BACKGROUND: The hospital mortality of patients suffering from pulmonary failure requiring venovenous extracorporeal membrane oxygenation (V-V ECMO) or extracorporeal carbon dioxide removal (ECCO2 R) is high. It is unclear whether outcome correlates with a hospital's annual procedural volume. METHODS: Data on all V-V ECMO and ECCO2 R cases treated from 2007 to 2019 were retrieved from the German Institute for Medical Documentation and Information. Comorbidities and outcomes were assessed by DRG, OPS, and ICD codes. The study population was divided into 5 groups depending on annual hospital V-V ECMO and ECCO2 R volumes (<10 cases; 10-19 cases; 20-29 cases; 30-49 cases; ≥50 cases). Primary outcome was hospital mortality. RESULTS: A total of 25 096 V-V ECMO and 3607 ECCO2 R cases were analyzed. V-V ECMO hospitals increased from 89 in 2007 to 214 in 2019. Hospitals handling <10 cases annually increased especially (64 in 2007 to 149 in 2019). V-V ECMO cases rose from 807 in 2007 to 2597 in 2019. Over 50% of cases were treated in hospitals handling ≥30 cases annually. Hospital mortality was independent of the annual hospital procedural volume (55.3%; 61.3%; 59.8%; 60.2%; 56.3%, respectively, p = 0.287). We detected no differences when comparing hospitals handling <30 cases to those with ≥30 annually (p = 0.659). The numbers of ECCO2 R hospitals and cases has dropped since 2011 (287 in 2007 to 48 in 2019). No correlation between annual hospital procedural volume and hospital mortality was identified (p = 0.914). CONCLUSION: The number of hospitals treating patients requiring V-V ECMO and V-V ECMO cases rose from 2007 to 2019, while ECCO2 R hospitals and their case numbers decreased. We detected no correlation between annual hospital V-V ECMO or ECCO2 R volume and hospital mortality.

Center Effects and Peritoneal Dialysis Peritonitis Outcomes: Analysis of a National Registry.

BACKGROUND: Peritonitis is a common cause of technique failure in peritoneal dialysis (PD). Dialysis center-level characteristics may influence PD peritonitis outcomes independent of patient-level characteristics. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Using Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) data, all incident Australian PD patients who had peritonitis from 2004 through 2014 were included. PREDICTORS: Patient- (including demographic data, causal organisms, and comorbid conditions) and center- (including center size, proportion of patients treated with PD, and summary measures related to type, cause, and outcome of peritonitis episodes) level predictors. OUTCOMES & MEASUREMENT: The primary outcome was cure of peritonitis with antibiotics. Secondary outcomes were peritonitis-related catheter removal, hemodialysis therapy transfer, peritonitis relapse/recurrence, hospitalization, and mortality. Outcomes were analyzed using multilevel mixed logistic regression. RESULTS: The study included 9,100 episodes of peritonitis among 4,428 patients across 51 centers. Cure with antibiotics was achieved in 6,285 (69%) peritonitis episodes and varied between 38% and 86% across centers. Centers with higher proportions of dialysis patients treated with PD (>29%) had significantly higher odds of peritonitis cure (adjusted OR, 1.21; 95% CI, 1.04-1.40) and lower odds of catheter removal (OR, 0.78; 95% CI, 0.62-0.97), hemodialysis therapy transfer (OR, 0.78; 95% CI, 0.62-0.97), and peritonitis relapse/recurrence (OR, 0.68; 95% CI, 0.48-0.98). Centers with higher proportions of peritonitis episodes receiving empirical antibiotics covering both Gram-positive and Gram-negative organisms had higher odds of cure with antibiotics (OR, 1.22; 95% CI, 1.06-1.42). Patient-level characteristics associated with higher odds of cure were younger age and less virulent causative organisms (coagulase-negative staphylococci, streptococci, and culture negative). The variation in odds of cure across centers was 9% higher after adjustment for patient-level characteristics, but 66% lower after adjustment for center-level characteristics. LIMITATIONS: Retrospective study design using registry data. CONCLUSIONS: These results suggest that center effects contribute substantially to the appreciable variation in PD peritonitis outcomes that exist across PD centers within Australia.

Waiting list and post-transplant outcome in Sweden after national centralization of heart transplant surgery.

BACKGROUND: Previous studies have demonstrated an association between transplantation rate per center and postoperative mortality after heart transplantation. In 2011, Sweden centralized heart transplants and waiting lists, reducing the number of centers from 3 to 2. We aimed to assess the active waiting time and pre- and post-transplant mortality before and after centralization. METHODS: Heart transplantations performed in Sweden between January 1, 2001 and December 31, 2020 were included. Background and donor organ supply data were collected from Scandiatransplant, the Swedish Thoracic Transplant Registry, and the Swedish Cardiac Surgery Registry. The Fine and Gray methods were applied to visualize cumulative incidence curves and conduct competing risk regressions. A Cox model was used to adjust for factors influencing time to post-transplant death. RESULTS: When comparing the two eras, the median active waiting time increased from 54 to 71 days (p = 0.015). The risk of mortality on the waiting list decreased in the later era (subhazard ratio 0.43; [95% confidence interval {CI} 0.25-0.74]; p = 0.002). The number of heart transplantation procedures (including pediatric patients) increased by 53%. There was a significant difference in organ utilization between eras (p = 0.033; chi-square test). 30-day and 1-year survival post-transplant rates for adults increased from 90.8% to 97.8% (p < 0.001) and from 87.9% to 94.6% (p < 0.001), respectively. 1-year mortality was reduced by 63% (hazard ratio 0.37; 95% CI 0.22-0.61). CONCLUSIONS: This nationwide study examined patients listed for and undergoing heart transplantation before and after the centralization of waiting lists and surgeries in Sweden. Waiting list mortality decreased, and 1-year post-transplantation survival was improved.

Does patient load affect clinical outcome of burn patients in specialized centers? An analysis of the German Burn Registry.

Hospital volume has been identified as an independent outcome parameter for a number of medical fields and surgical procedures, and there is a tendency to increase required patient numbers for center verification. However, the existing literature does not support a clear correlation between patient load and clinical outcome in adult burn care and recent data from Germany does not exist. We therefore evaluated the effect of patient volume in German burn centers on clinical outcome. Patient data was extracted from the German Burn Registry from 2015 to 2018. For better inter-center comparability, solely burn patients with a TBSA ≥ 10% were included. Mortality, number of surgeries and length of stay (LOS) were evaluated with respect to burn center patient volume. Burn center volume was divided into two and three groups. A total of 2718 patients with a TBSA ≥ 10% were admitted to the participating 17 burn centers. Independent from the division of patient data into either 2 or 3 groups, the TBSA and ABSI score-related severity of burn injuries were comparable between groups. There was no significant difference in mortality due to center size. Nevertheless, patients treated in large volume burn centers showed a significantly increased LOS (+4.5 days, [1.9-7.2] CI, p = 0.001) and required significantly more surgeries (+0.5 surgeries [0.2-0.8] CI, p = 0.002) when compared to the small volume centers. A similar phenomenon regarding mortality and LOS (p 0.001) was observed after dividing the centers into two groups. Interestingly a division into three groups showed significant differences with the best outcome for patients in medium-volume centers. Nevertheless, mortality did not differ significantly. Therefore, our data demonstrates that in contrast to many other medical fields, outcome and mortality are not automatically improved in burn care by simply increasing the patient load, at least in centers treating 20-100 BICU patients/year.

Letter to the Editor: Analysis of stroke patient migration for mechanical thrombectomy and changes in neurointerventional center size in Germany.

AIM AND METHODS: To analyse nationwide changes in neurointerventional center size of all German hospitals performing mechanical thrombectomy (MT) in stroke patients from 2016 to 2019. Furthermore, we assessed cross-district patient migration for MT for the first time using hospitals' structured quality reports and German Diagnosis-Related Groups data in 2019. FINDINGS: Number of hospitals performing more than 100 MT procedures/year doubled in Germany from 2016 (n = 36) to 2019 (n = 71), and these neurointerventional centers performed 71% of all MT procedures in 2019. The overall increase in MT procedures was largely driven by these high-volume neurointerventional centers with ability to perform MT 24/7 (121% increase as compared with 8% increase in hospitals performing less than 100 MT procedures/year). The highest cross-district patient mobility/transfer of stroke patients for MT was observed in districts adjacent to these high-volume neurointerventional centers with existing neurovascular networks. CONCLUSION: The substantial increase in MT procedures observed in Germany between 2016 and 2019 was almost exclusively delivered by high-volume stroke centers performing more than 100 MT procedures per year in established neurovascular networks. As there is still a reasonable number of districts with low MT rates, further structural improvement including implementation of new or expansion of existing neurovascular networks and regional tailored MT triage concepts is needed.

Center-Effect of Incident Hemodialysis Vascular Access Use: Analysis of a Bi-national Registry.

Background: Commencing hemodialysis (HD) with an arteriovenous access is associated with superior patient outcomes compared with a catheter, but the majority of patients in Australia and New Zealand initiate HD with a central venous catheter. This study examined patient and center factors associated with arteriovenous fistula/graft access use at HD commencement. Methods: We included all adult patients starting chronic HD in Australia and New Zealand between 2004 and 2015. Access type at HD initiation was analyzed using logistic regression. Patient-level factors included sex, age, race, body mass index (BMI), smoking status, primary kidney disease, late nephrologist referral, comorbidities, and prior RRT. Center-level factors included size; transplant capability; home HD proportion; incident peritoneal dialysis (average number of patients commencing RRT with peritoneal dialysis per year); mean weekly HD hours; average blood flow; and achievement of phosphate, hemoglobin, and weekly Kt/V targets. The study included 27,123 patients from 61 centers. Results: Arteriovenous access use at HD commencement varied four-fold from 15% to 62% (median 39%) across centers. Incident arteriovenous access use was more likely in patients aged 51-72 years, males, and patients with a BMI of >25 kg/m2 and polycystic kidney disease; but use was less likely in patients with a BMI of <18.5 kg/m2, late nephrologist referral, diabetes mellitus, cardiovascular disease, chronic lung disease, and prior RRT. Starting HD with an arteriovenous access was less likely in centers with the highest proportion of home HD, and no center factor was associated with higher arteriovenous access use. Adjustment for center-level characteristics resulted in a 25% reduction in observed intercenter variability of arteriovenous access use at HD initiation compared with the model adjusted for only patient-level characteristics. Conclusions: This study identified several patient and center factors associated with incident HD access use, yet these factors did not fully explain the substantial variability in arteriovenous access use across centers.

Concordance Between Biopsy and Radical Prostatectomy Gleason Scores: Evaluation of Determinants in a Large-Scale Study of Patients Undergoing RARP in Belgium.

To determine whether Gleason scores were concordant between prostate biopsies (bGS) and the definitive resection specimen (pGS) excised with robot-assisted radical prostatectomy (RARP); to identify clinical and pathological factors that might predict upgrading; and to evaluate how upgrading affected outcome. Between 2009 and 2016, 25 Belgian centers participated in collecting prospective data for patients that underwent RARP. We analyzed the concordance rate between the bGS and the pGS in 8021 patients with kappa statistics, and we compared concordance rates from different centers. We assessed the effect of several clinical and pathological factors on the concordance rate with logistic regression analysis. The concordance rate for the entire population was 62.9%. Upgrading from bGS to pGS occurred in 27.3% of patients. The number of biopsies was significantly associated with concordance. Older age (>60 y), a higher clinical T stage (≥cT2), a higher PSA value at the time of biopsy (>10 ng/ml), and more time between the biopsy and the radical prostatectomy were significantly associated with a higher risk of upgrading. Positive margins and PSA relapse occurred more frequently in upgraded patients. Center size did not significantly affect the concordance rate (p = 0.40).This prospective, nationwide analysis demonstrated a Gleason score concordance rate of 62.9%. Upgrading was most frequently observed in the non-concordant group. We identified clinical and pathological factors associated with (non)-concordance. Upgrading was associated with a worse oncological outcome. Center volume was not associated with pathological accuracy.

Children with onset-ketoacidosis are admitted to the nearest hospital available, regardless of center size.

Background To investigate longitudinal trends of admissions with diabetic ketoacidosis (DKA) in new-onset type 1 diabetes (T1D) and subsequent duration of hospitalization in association with structural health care properties, such as size of treatment facility, population density and linear distance between home and treatment centers. Methods Data from 24,321 German and Austrian pediatric patients with newly-diagnosed T1D between 2008 and 2017 within the DPV registry were analyzed. Results Onset-DKA rates fluctuated at around 19% and slightly increased over the observation period (p<0.001). Compared to children without onset-DKA, children with onset-DKA were more frequently treated at centers located closer to their homes, independent of center size or urbanity. Annual median duration of hospitalization decreased from 13.1 (12.6;13.6) to 12.7 (12.3;13.2) days (p<0.001). It was highest in patients younger than 5 years, with migration background, and in severe DKA. Conclusion Patients with onset-DKA are admitted to the nearest hospital, independent of center size. Facilities close to patients' homes therefore play an important role in the acute management of T1D onset. In Germany and Austria, diabetes education at diagnosis is mainly performed in inpatient settings. This is reflected by a long duration of hospitalization, which has decreased only slightly over the past decade.

High glucose levels impact visual response properties of retinal ganglion cells in C57 mice-An in vitro physiological study.

This study investigated visual response properties of retinal ganglion cells (RGCs) under high glucose levels. Extracellular single-unit responses of RGCs from mouse retinas were recorded. And the eyecup was prepared as a flat mount in a recording chamber and superfused with Ames medium. The averaged RF size of the ON RGCs (34.1±2.9, n=14) was significantly smaller than the OFF RGCs under the HG (49.3±0.3, n=12) (P<0.0001) conditions. The same reduction pattern was also observed in the osmotic control group (HM) between ON and OFF RGCs (P<0.0001). The averaged luminance threshold (LT) of ON RGCs increased significantly under HG or HM (HG: P<0.0001; HM: P<0.0002). OFF RGCs exhibited a similar response pattern under the same conditions (HG: P<0.01; HM: P<0.0002). The averaged contrast gain of ON cells was significantly lower than that of OFF cells with the HM treatment (P<0.015, unpaired Student's t test). The averaged contrast gain of ON cells was significantly higher than OFF cells with the HG treatment (P<0.0001). The present results suggest that HG reduced receptive field center size, suppressed luminance threshold, and attenuated contrast gain of RGCs. The impact of HG on ON and OFF RGCs may be mediated via different mechanisms.

Examining the relationship between social support availability, urban center size, and self-perceived mental health of recent immigrants to Canada: a mixed-methods analysis.

The experiences of settlement in a new country (e.g., securing housing and employment, language barriers) pose numerous challenges for recent immigrants that can impede their health and well-being. Lack of social support upon arrival and during settlement may help to explain why immigrant mental health status declines over time. While most urban centers in Canada offer some settlement services, little is known about how the availability of social supports, and the health statuses of recent immigrants, varies by city size. The objective of this mixed-methods study was to examine the relationship between self-perceived mental health (SPMH), social support availability, and urban center size, for recent immigrants to Canada. The quantitative component involved analysis of 2009-2010 Canadian Community Health Survey data, selecting for only recent immigrants and for those living in either large or small urban centers. The qualitative component involved in-depth interviews with managers of settlement service organizations located in three large and three small urban centers in Canada. The quantitative analysis revealed that social support availability is positively associated with higher SPMH status, and is higher in small urban centers. In support of these findings, our interviews revealed that settlement service organizations operating in small urban centers offer more intensive social supports; interviewees attributed this difference to personal relationships in small cities, and the ease with which they can connect to other agencies to provide clients with necessary supports. Logistic regression analysis revealed, however, that recent immigrants in small urban centers are twice as likely to report low SPMH compared to those living in large urban centers. Thus, while the scope and nature of settlements services appears to vary by city size in Canada, more research is needed to understand what effect settlement services have on the health status of recent immigrants to Canada, especially in smaller urban centers.