Impact of dose volume parameters and clinical characteristics on radiation-induced acute oral mucositis for head and neck cancer patients treated with carbon-ion radiotherapy dose volume outcome analysis.

OBJECTIVES: To assess the predictive value of different dosimetric parameters for acute radiation oral mucositis (ROM) in head and neck cancer (HNCs) patients treated with carbon-ion radiotherapy (CIRT). METHODS: 44 patients with HNCs treated with CIRT were evaluated for acute ROM which was defined as severe when the score ≥3 (acute ROM was scored prospectively using the Radiation Therapy Oncology Group (RTOG) score system). Predictive dosimetric factors were identified by using univariate and multivariate analysis. RESULTS: Male gender, weight loss >5%, and total dose/fractions were related factors to severe ROM. In multivariate analysis, grade ≥3 ROM was significantly related to the Dmax, D10, D15, and D20 (P < 0.05, respectively). As the receiver operating characteristics (ROC) curve shows, the area under the curve (AUC) for D10 was 0.77 (p = 0.003), and the cutoff value was 51.06 Gy (RBE); The AUC for D15 was 0.75 (p = 0.006), and the cutoff value was 42.82 Gy (RBE); The AUC for D20 was 0.74 (p = 0.009), and the cutoff value was 30.45 Gy (RBE); The AUC for Dmax was 0.81 (p < 0.001), and the cutoff value was 69.33 Gy (RBE). CONCLUSION: Male gender, weight loss, and total dose/fractions were significantly association with ROM. Dmax, D10, D15 and D20 were identified as the most valuable predictor and we suggest a Dmax limit of 69.33 Gy (RBE), D10 limit of 51.06 Gy (RBE), D15 limit of 42.82 Gy (RBE), and D20 limit of 30.45 Gy (RBE) and for oral mucosa.

Volume-Outcome Relationships for Intra-Aortic Balloon Pump in Acute Myocardial Infarction.

BACKGROUND: Acute myocardial infarction (AMI) is a major scenario for the use of an intra-aortic balloon pump (IABP), particularly when complicated by cardiogenic shock, although the utilization of mechanical circulatory support devices varies widely per hospital. We evaluated the relationship, at the hospital level, between the volume of IABP use and mortality in AMI. METHODS AND RESULTS: Using a Japanese nationwide administrative database, 26,490 patients with AMI undergoing primary percutaneous coronary intervention (PCI) from 154 hospitals were included in this study. The primary endpoint was the observed-to-predicted in-hospital mortality ratio. Predicted mortality per patient was calculated using baseline variables and averaged for each hospital. The associations among PCI volume for AMI, observed and predicted in-hospital mortality, and observed and predicted IABP use were assessed per hospital. Of 26,490 patients, 2,959 (11.2%) were treated with IABP and 1,283 (4.8%) died during hospitalization. The annualized number of uses of IABP per hospital in AMI was 4.5. In lower-volume primary PCI centers, IABP was more likely to be underused than expected, and the observed-to-predicted in-hospital mortality ratio was higher than in higher-volume centers. CONCLUSIONS: A lower annual number of IABP use was associated with an increased mortality risk at the hospital level, suggesting that IABP use can be an institutional quality indicator in the setting of AMI.

Is centralization for rectal cancer surgery necessary?

Rectal cancer surgery is complex and more technically challenging than colonic surgery. Over the last 30 years internationally, there has been a growing impetus for centralizing care to improve outcomes for rectal cancer. Centralizing care may potentially reduce variations of care, increase standardization and compliance with clinical practice guidelines. However, there are barriers to implementation at a professional, political, governance and resource allocation level. Centralization may increase inequalities to accessing healthcare, particularly impacting socioeconomically disadvantaged and rural populations with difficulties to commuting longer distances to "centres of excellence". Furthermore, it is unclear if centralization actually improves outcomes. Recent studies demonstrate that individual surgeon volume rather than hospital volume may be more important in achieving optimal outcomes. In this review, we examine the literature to assess the value of centralization for rectal cancer surgery.

Association between hospital palliative care team intervention volume and patient outcomes.

BACKGROUND: The benefits of palliative care in patients with advanced cancer are well established. However, the effect of the skills of the palliative care team (PCT) on patient outcomes remains unclear. Our aim was to evaluate the association between hospital PCT intervention volume and patient outcomes in patients with cancer. METHODS: A retrospective cohort study was conducted using a nationwide inpatient database in Japan. Patients with cancer receiving chemotherapy and PCT intervention from 2015 to 2020 were included. The outcomes were incidence of hyperactive delirium within 30 days of admission, mortality within 30 days of admission, and decline in activities of daily living (ADL) at discharge. The exposure of interest was hospital PCT intervention volume (annual number of new PCT interventions in a hospital), which was categorized into low-, intermediate-, and high-volume groups according to tertiles. Multivariate logistic regression and restricted cubic-spline regression were conducted. RESULTS: Of 29,076 patients, 1495 (5.1%), 562 (1.9%), and 3026 (10.4%) developed delirium, mortality, and decline in ADL, respectively. Compared with the low hospital PCT intervention volume group (1-103 cases/year, n = 9712), the intermediate (104-195, n = 9664) and high (196-679, n = 9700) volume groups showed significant association with lower odds ratios of 30-day delirium (odds ratio, 0.79 [95% confidence interval, 0.69-0.91] and 0.80 [0.69-0.93], respectively), 30-day mortality (0.73 [0.60-0.90] and 0.59 [0.46-0.75], respectively), and decline in ADL (0.77 [0.70-0.84] and 0.52 [0.47-0.58], respectively). CONCLUSION: Hospital PCT intervention volume is inversely associated with the odds ratios of delirium, mortality, and decline in ADL among hospitalized patients with cancer.

Type A aortic dissection: optimal annual case volume for surgery.

BACKGROUND AND AIMS: 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. METHODS: 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. RESULTS: 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]. CONCLUSIONS: 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.

Impact of Hospital Volume on Long-Term Outcomes After Endovascular Therapy for Peripheral Artery Disease.

PURPOSE: To investigate the association between annual hospital volume of endovascular therapy (EVT) and long-term outcomes in patients with lower-extremity peripheral artery disease (PAD). MATERIALS AND METHODS: We identified patients who underwent percutaneous endovascular transluminal angioplasty and thrombectomy of the extremities or percutaneous endovascular removal in the Japanese Diagnosis Procedure Combination inpatient database from April 2014 to March 2020 linked to the Survey of Medical Institutions data. A generalized linear model analysis was performed to assess 12-month amputation, all-cause death, composite outcome (amputation and death), and readmission. We also analyzed length of hospital stay and total health care costs during the first hospitalization. RESULTS: Among 127 486 eligible patients, 31 579, 31 913, 31 999, and 31 995 were in the first (1-27 cases/year), second (28-44 cases), third (45-67 cases), and fourth (68-289 cases) quartiles, respectively. There were no significant differences in 12-month amputation among the second (odds ratio [OR], 0.97; 95% confidence interval [CI], 0.90-1.04), third (OR, 1.00; 95% CI, 0.93-1.07), and fourth (OR, 1.00; 95% CI, 0.93-1.07) quartile volumes compared with the first quartile. Significant differences were observed in 12-month death (OR for fourth quartile with reference to the first quartile, 0.71; 95% CI, 0.65-0.76), composite outcome (OR, 0.84; 95% CI, 0.80-0.89), and readmission (OR, 1.05; 95% CI, 1.02-1.09). CONCLUSIONS: We found that the annual hospital volume of EVT was not associated with decreased 12-month amputation in patients with lower-extremity PAD. In contrast, all-cause death and composite outcome were significantly decreased in hospitals with the highest volume. CLINICAL IMPACT: The association between hospital volume of endovascular therapy and long-term adverse clinical outcomes remains unclear. The present analyses showed no significant differences in 12-month amputation rates among the hospital volumes, whereas higher-volume quartiles were significantly associated with decreased 12-month all-cause death rates and composite outcome. There was also a positive association in the length of stay between the first quartile volume and the others, while no significant difference in total health care costs among the quartiles was observed. Further investigations are needed, including insights into operator volume and procedural characteristics, to clarify the relationship between hospital volume and long-term adverse outcomes.

Nationwide volume-outcome relationship concerning in-hospital mortality and failure-to-rescue in surgery of sigmoid diverticulitis.

PURPOSE: A correlation between the hospital volume and outcome is described for multiple entities of oncological surgery. To date, this has not been analyzed for the surgical treatment of sigmoid diverticulitis. The aim of this study was to explore the impact of the annual caseload per hospital of colon resection on the postoperative incidence of complications, failure to rescue, and mortality in patients with diverticulitis. METHODS: Patients receiving colorectal resection independent from the diagnosis from 2012 to 2017 were selected from a German nationwide administrative dataset. The hospitals were grouped into five equal caseload quintiles (Q1-Q5 in ascending caseload order). The outcome analysis was focused on patients receiving surgery for sigmoid diverticulitis. RESULTS: In total, 662,706 left-sided colon resections were recorded between 2012 and 2017. Of these, 156,462 resections were performed due to sigmoid diverticulitis and were included in the analysis. The overall in-house mortality rate was 3.5%, ranging from 3.8% in Q1 (mean of 9.5 procedures per year) to 3.1% in Q5 (mean 62.8 procedures per year; p < 0.001). Q5 hospitals revealed a risk-adjusted odds ratio of 0.85 (95% CI 0.78-0.94; p < 0.001) for in-hospital mortality compared to Q1 during multivariable logistic regression analysis. High-volume centers showed overall lower complication rates, whereas the failure-to-rescue did not differ significantly. CONCLUSION: Surgical treatment of sigmoid diverticulitis in high-volume colorectal centers shows lower postoperative mortality rates and fewer postoperative complications.

Surgeon supply and healthcare quality: Are revision rates for hip and knee replacements lower in hospitals that employ more surgeons?

We study the link between department-wide surgeon supply and quality of care for two major elective medical procedures. Several countries have adopted policies to concentrate medical procedures in high-volume hospitals. While higher patient volumes might translate to higher quality, we provide evidence for a positive relationship between surgeon supply and hospital revision rates for hip and knee replacement surgery. Hence, hospital performance decreases with higher surgeon supply, and this finding holds conditional on patient volumes.

Selective referral or learning by doing? An analysis of hospital volume-outcome relationship of vascular procedures.

This paper analyzes the effects of hospital volume on outcomes of patients undergoing percutaneous transluminal angioplasty (PTA) with stent implant in Slovakia between 2014 and 2019. The volume-outcome relationship is estimated jointly using a discrete factor approach, where choice of hospital is correlated with durations until readmission or death, accounting for observed and unobserved characteristics. The results reveal the importance of controlling for between-hospital differences and selectivity in patient referral. Estimates without hospital fixed effects overstate the positive effect of volume on outcomes, but the results remain statistically significant. Once selectivity is accounted for in the joint correlated model, the positive volume-outcome relationship is not different from zero. Overall, the main driver of the volume-outcome relationship for PTA procedures appears to be related to selective referral and differences in quality of health care providers.

Surgical volume and outcomes of surgical ablation for atrial fibrillation: a nationwide population-based cohort study.

BACKGROUND: Atrial fibrillation is the most common cardiac arrythmia and causes many complications. Sinus rhythm restoration could reduce late mortality of atrial fibrillation patients. The Maze procedure is the gold standard for surgical ablation of atrial fibrillation. Higher surgical volume has been documented with favorable outcomes of various cardiac procedures such as mitral valve surgery and aortic valve replacement. We aimed to determine the volume-outcome relationship (i.e., association between surgical volume and outcomes) for the concomitant Maze procedure during major cardiac surgeries. METHODS: This nationwide population-based cohort study retrieved data from the Taiwan National Health Insurance Research Database. Adult patients undergoing concomitant Maze procedures during 2010-2017 were identified; consequently, 2666 patients were classified into four subgroups based on hospital cumulative surgery volumes. In-hospital outcomes and late outcomes during follow-up were analyzed. Logistic regression and Cox proportional hazards model were used to analyze the volume-outcome relationship. RESULTS: Patients undergoing Maze procedures at lower-volume hospitals tended to be frailer and had higher comorbidity scores. Patients in the highest-volume hospitals had a lower risk of in-hospital mortality than those in the lowest-volume hospitals [adjusted odds ratio, 0.30; 95% confidence interval (CI), 0.15-0.61; P < 0.001]. Patients in the highest-volume hospitals had lower rates of late mortality than those in the lowest-volume hospitals, including all-cause mortality [adjusted hazard ratio (aHR) 0.53; 95% CI 0.40-0.68; P < 0.001] and all-cause mortality after discharge (aHR 0.60; 95% CI 0.44-0.80; P < 0.001). CONCLUSIONS: A positive hospital volume-outcome relationship for concomitant Maze procedures was demonstrated for in-hospital and late follow-up mortality. The consequence may be attributed to physician skill/experience, experienced multidisciplinary teams, and comprehensive care processes. We suggest referring patients with frailty or those requiring complicated cardiac surgeries to high-volume hospitals to improve clinical outcomes. TRIAL REGISTRATION: the institutional review board of Chang Gung Memorial Hospital approved all data usage and the study protocol (registration number: 202100151B0C502).

What is the impact of hospital and surgeon volumes on outcomes in rectal cancer surgery?

AIM: Evidence for a positive volume-outcome relationship for rectal cancer surgery is unclear. This study aims to evaluate the volume-outcome relationship for rectal cancer surgery at hospital and surgeon level in the English National Health Service (NHS). METHOD: All patients undergoing a rectal cancer resection in the English NHS between 2015 and 2019 were included. Multilevel multivariable logistic regression was used to model relationships between outcomes and mean annual hospital and surgeon volumes (using a linear plus a quadratic term for volume) with adjustment for patient characteristics. RESULTS: A total of 13 858 patients treated in 166 hospitals were included. Six hospitals (3.6%) performed fewer than 10 rectal cancer resections per year, and 381 surgeons (45.0%) performed fewer than five such resections per year. Patients treated by high-volume surgeons had a reduced length of stay (p = 0.016). No statistically significant volume-outcome relationships were demonstrated for 90-day mortality, 30-day unplanned readmission, unplanned return to theatre, stoma at 18 months following anterior resection, positive circumferential resection margin and 2-year all-cause mortality at either hospital or surgeon level (p values > 0.05). CONCLUSION: Almost half of colorectal surgeons in England do not meet national guidelines for rectal cancer surgeons to perform a minimum of five major resections annually. However, our results suggest that centralizing rectal cancer surgery with the main focus of increasing operative volume may have limited impact on NHS surgical outcomes. Therefore, quality improvement initiatives should address a wider range of evidence-based process measures, across the multidisciplinary care pathway, to enhance outcomes for patients with rectal cancer.

The Effects of Hospital Volume on Short-Term Outcomes of Laparoscopic Surgery for Rectal Cancer: A Large-Scale Analysis of 37,821 Cases on a Nationwide Administrative Database.

INTRODUCTION: Laparoscopic low anterior resection (L-LAR) has become widely accepted for the treatment of rectal cancer. However, little is known about the superiority of L-LAR in a real-world setting (including low-volume hospitals) and the association between the short-term outcomes and hospital volume focusing on L-LAR. METHODS: This is a retrospective cohort study. A total of 37,821 patients who underwent LAR for rectal cancer were analyzed using the Diagnosis Procedure Combination (DPC) database from January 2014 to December 2017. The short-term surgical outcomes were analyzed using a multilevel analysis. Hospital volumes were divided into quartiles, including low (1-31), middle (32-55), high (56-91), and very-high volume (92-444 resections per 4 years). The effects of hospital volume on the outcomes were investigated. RESULTS: The study population included 8,335 patients (22%) who underwent open low anterior resection (O-LAR) and 29,486 patients (78%) who underwent L-LAR. The in-hospital mortality and morbidity were consistent with previous reports. In patients who underwent L-LAR, the in-hospital mortality (0.12% vs. 0.41%; OR: 0.33; p = 0.005), the rate of reoperation (3.76% vs. 6.48%; OR: 0.67; p < 0.001), and the perioperative transfusion rate (3.81% vs. 5.90%; OR: 0.66; p < 0.001) were significantly lower in very-high-volume hospitals than in low-volume hospitals. These effects of hospital volume were not observed in O-LAR. CONCLUSIONS: Our present study demonstrates that high volume improves outcomes in patients who underwent L-LAR in a real-world setting.

How to direct patients to high-volume hospitals: exploring the influencing drivers.

BACKGROUND: During the last decade, planning concentration policies have been applied in healthcare systems. Among them, attention has been given to guiding patients towards high-volume hospitals that perform better, acccording to the volume-outcome association. This paper analyses which factors drive patients to choose big or small hospitals (with respect to the international standards of volumes of activity). METHODS: We examined colon cancer surgeries performed in Piedmont (Italy) between 2004 and 2018. We categorised the patient choice of the hospital as big/small, and we used this outcome as main dependent variable of descriptive statistics, tests and logistic regression models. As independent variables, we included (i) patient characteristics, (ii) characteristics of the closest big hospital (which should be perceived as the most immediate to be chosen), and (iii) territorial characteristics (i.e., characteristics of the set of hospitals among which the patient can choose). We also considered interactions among variables to examine which factors influence all or a subset of patients. RESULTS: Our results confirm that patient personal characteristics (such as age) and hospital characteristics (such as distance) play a primary role in the patient decision process. The findings seem to support the importance of closing small hospitals when they are close to big hospitals, although differences emerge between rural and urban areas. Other interesting insights are provided by examining the interactions between factors, e.g., patients affected by comorbidities are more responsive to hospital quality even though they are distant. CONCLUSIONS: Reorganising healthcare services to concentrate them in high-volume hospitals emerged as a crucial issue more than forty years ago. Evidence suggests that concentration strategies guarantee better clinical performance. However, in healthcare systems in which patients are free to choose where to be treated, understanding patients' behaviour and what drives them towards the most effective choice is of paramount importance. Our study builds on previous research that has already analysed factors influencing patients' choices, and takes a step further to enlighten which factors drive patients to choose between a small or a big hospital (in terms of volume). The results could be used by decision makers to design the best concentration strategy.

The volume-outcome relationship for endoscopic transsphenoidal pituitary surgery for benign neoplasm: analysis of an administrative dataset for England.

BACKGROUND: Setting minimum annual volume thresholds for pituitary surgery in England is seen as one way of improving outcomes for patients and service efficiency. However, there are few recent studies from the UK on whether a volume-outcome effect exists, particularly in the era of endoscopic surgery. Such data are needed to allow evidence-based decision making. The aim of this study was to use administrative data to investigate volume-outcome effects for endoscopic transsphenoidal pituitary surgery in England. METHODS: Data from the Hospital Episodes Statistics database for adult endoscopic transsphenoidal pituitary surgery for benign neoplasm conducted in England from April 2013 to March 2019 (inclusive) were extracted. Annual surgeon and trust volume was defined as the number of procedures conducted in the 12 months prior to the index procedure. Volume was categorised as < 10, 10-19, 20-29, 30-39 and ≥40 procedures for surgeon volume and < 20, 20-39, 40-59, 60-79 and ≥80 procedures for trust volume. The primary outcome was repeat ETSPS during the index procedure or during a hospital admission within one-year of discharge from the index procedure. RESULTS: Data were available for 4590 endoscopic transsphenoidal pituitary procedures. After adjustment for covariates, higher surgeon volume was significantly associated with reduced risk of repeat surgery within one year (odds ratio (OR) 0.991 (95% confidence interval (CI) 0.982-1.000)), post-procedural haemorrhage (OR 0.977 (95% CI 0.967-0.987)) and length of stay greater than the median (0.716 (0.597-0.859)). A higher trust volume was associated with reduced risk of post-procedural haemorrhage (OR 0.992 (95% CI 0.985-0.999)), but with none of the other patient outcomes studied. CONCLUSIONS: A surgeon volume-outcome relationship exists for endoscopic transsphenoidal pituitary surgery in England.

Surgeon volume and established hospital perioperative mortality rate together predict for superior outcomes after open abdominal aortic aneurysm repair.

BACKGROUND: In 2018, the Society for Vascular Surgery (SVS) published hospital volume guidelines for elective open abdominal aortic aneurysm (AAA) repair, recommending that elective open surgical repair of AAAs should be performed at centers with an annual volume of ≥10 open aortic operations of any type and a documented perioperative mortality of ≤5%. Recent work has suggested a yearly surgeon volume of at least seven open aortic cases for improved outcomes. The objective of the present study was to assess the importance of hospital volume and surgeon volume at these cut points for predicting 1-year mortality after open surgical repair of AAAs. METHODS: We evaluated patients who had undergone elective open AAA repair using the New York Statewide Planning and Research Cooperative System database from 2003 to 2014. The effect of the SVS guidelines on postoperative mortality and complications was evaluated. Confounding between the hospital and surgeon volumes was identified using mixed effects multivariate Cox proportional hazards analysis. The effect of the interactions between hospital volume, established hospital perioperative survival, and surgeon volume on postoperative outcomes was also investigated. RESULTS: The cohort consisted of 7594 elective open AAA repairs performed by 542 surgeons in 137 hospitals during the 12-year study period. Analysis of the 2018 guidelines using the Statewide Planning and Research Cooperative System database revealed 1-year and 30-day mortality rates of 9.2% (range, 8.3%-10.1%) and 3.5% (range, 2.9%-4.1%) for centers that were within the SVS guidelines and 13.6% (range, 12.5%-14.7%) and 6.9% (range, 6.1%-7.8%) for those that were outside the guidelines, respectively (P < .001 for both). Multivariate survival analysis revealed a hazard ratio for a surgeon volume of ≥7, hospital volume of ≥10, and hospital 3-year perioperative mortality of ≤5% of 0.80 (95% confidence interval [CI], 0.70-0.93; P = .003), 0.91 (95% CI, 0.77-1.08; P = .298), and 0.72 (95% CI, 0.62-0.82; P < .001), respectively. Additionally, procedures performed by surgeons with a yearly average volume of open aortic operations of at least seven and at hospitals with an established elective open AAA repair perioperative mortality rate of ≤5% showed improved 1-year (33.2% relative risk reduction; P < .001) and 30-day (P = .001) all-cause survival and improved postoperative complication rates. CONCLUSIONS: These data have demonstrated that centers that meet the SVS AAA volume guidelines are associated with improved 1-year and 30-day all-cause survival. However, the results were confounded by surgeon volume. A surgeon open aortic volume of at least seven procedures and an established hospital perioperative mortality of ≤5% each independently predicted for 1-year survival after open AAA repair, with the hospital volume less important. These results indicate that surgeons with an annual volume of at least seven open aortic operations of any type should perform elective open AAA repair at centers with a documented perioperative mortality of ≤5%.

An observational study of volume-outcome effects for robot-assisted radical prostatectomy in England.

OBJECTIVES: To investigate volume-outcome relationships in robot-assisted radical prostatectomy (RARP) for cancer using data from the Hospital Episodes Statistics (HES) database for England. MATERIALS AND METHODS: Data for all adult, elective RPs for cancer during the period January 2013-December 2018 (inclusive) were extracted from the HES database. The HES database records data on all National Health Service (NHS) hospital admissions in England. Data were extracted for the NHS trust and surgeon undertaking the procedure, the surgical technique used (laparoscopic, open or robot-assisted), hospital length of stay (LOS), emergency readmissions, and deaths. Multilevel modelling was used to adjust for hierarchy and covariates. RESULTS: Data were available for 35 629 RPs (27 945 RARPs). The proportion of procedures conducted as RARPs increased from 53.2% in 2013 to 92.6% in 2018. For RARP, there was a significant relationship between 90-day emergency hospital readmission (primary outcome) and trust volume (odds ratio [OR] for volume decrease of 10 procedures: 0.99, 95% confidence interval [CI] 0.99-1.00; P = 0.037) and surgeon volume (OR for volume decrease of 10 procedures: 0.99, 95% CI 0.99-1.00; P = 0.013) in the previous year. From lowest to highest volume category there was a decline in the adjusted proportion of patients readmitted as an emergency at 90 days from 10.6% (0-49 procedures) to 7.0% (≥300 procedures) for trusts and from 9.4% (0-9 procedures) to 8.3% (≥100 procedures) for surgeons. LOS was also significantly associated with surgeon and trust volume, although 1-year mortality was associated with neither. CONCLUSIONS: There is evidence of a volume-outcome relationship for RARP in England and minimising low-volume RARP will improve patient outcomes. Nevertheless, the observed effect size was relatively modest, and stakeholders should be realistic when evaluating the likely impact of further centralisation at a population level.

Hospital surgical volume-outcome relationship in caesarean hysterectomy for placenta accreta spectrum.

OBJECTIVE: To examine the association between hospital surgical volume of caesarean hysterectomy and surgical morbidity in women with placenta accreta spectrum (PAS). DESIGN: Population-based retrospective cohort study. SETTING: National Inpatient Sample, January 2016 to December 2018. POPULATION: Six thousand and ten women with PAS who underwent caesarean hysterectomy in 738 centres. METHODS: (1) Comprehensive modelling for relative hospital surgical volume cut-point selection, (2) multinomial regression analysis for characterising hospital surgical volume, and (3) binary logistic regression analysis to examine the volume-outcome relationship. MAIN OUTCOME MEASURES: Surgical morbidity (haemorrhage, coagulopathy, shock, urinary tract injury, and death). RESULTS: The majority of centres had five surgeries over the 3-year period (468 centres, 63.4%) and were grouped as the low-volume group. Surgical morbidity decreased after a relative hospital surgical volume of 25 cases (24 centres, 3.3%) was reached, grouped as the high-volume group. The remaining centres were grouped as the mid-volume group (246 centres, 33.3%). In multivariable analysis, women in the high-volume group were more likely to be Black, have lower median household income, medical comorbidity, previous caesarean delivery, placenta praevia or placenta percreta, and to have undergone surgeries at large urban teaching hospitals compared with those in the low-volume group (all, P < 0.05). After controlling for patient demographics, hospital characteristics and pregnancy factors, performance of caesarean hysterectomy at high-volume centres was associated with a 22% decreased risk of surgical complications compared with surgery at the low-volume centres (adjusted odds ratio 0.78, 95% CI 0.64-0.94). CONCLUSION: Caesarean hysterectomy for PAS is a rare surgical procedure. Higher hospital surgical volume may be associated with improved surgical outcome in PAS. TWEETABLE ABSTRACT: Higher hospital caesarean hysterectomy volume may be associated with improved surgical outcome in PAS.

Hospital Academic Status and the Volume-Outcome Association in Postoperative Patients Requiring Intensive Care: Results of a Nationwide Analysis of Intensive Care Units in the United States.

Objective: To determine whether the outcomes of postoperative patients admitted directly to an intensive care unit (ICU) differ based on the academic status of the institution and the total operative volume of the unit. Methods: This was a retrospective analysis using the eICU Collaborative Research Database v2.0, a national database from participating ICUs in the United States. All patients admitted directly to the ICU from the operating room were included. Transfer patients and patients readmitted to the ICU were excluded. Patients were stratified based on admission to an ICU in an academic medical center (AMC) versus non-AMC, and to ICUs with different operative volume experience, after stratification in quartiles (high, medium-high, medium-low, and low volume). Primary outcomes were ICU and hospital mortality. Secondary outcomes included the need for continuous renal replacement therapy (CRRT) during ICU stay, ICU length of stay (LOS), and 30-day ventilator free days. Results: Our analysis included 22,180 unique patients; the majority of which (15,085[68%]) were admitted to ICUs in non-AMCs. Cardiac and vascular procedures were the most common types of procedures performed. Patients admitted to AMCs were more likely to be younger and less likely to be Hispanic or Asian. Multivariable logistic regression indicated no meaningful association between academic status and ICU mortality, hospital mortality, initiation of CRRT, duration of ICU LOS, or 30-day ventilator-free-days. Contrarily, medium-high operative volume units had higher ICU mortality (OR = 1.45, 95%CI = 1.10-1.91, p-value = 0.040), higher hospital mortality (OR = 1.33, 95%CI = 1.07-1.66, p-value = 0.033), longer ICU LOS (Coefficient = 0.23, 95%CI = 0.07-0.39, p-value = 0.038), and fewer 30-day ventilator-free-days (Coefficient = -0.30, 95%CI = -0.48 - -0.13, p-value = 0.015) compared to their high operative volume counterparts. Conclusions: This study found that a volume-outcome association in the management of postoperative patients requiring ICU level of care immediately after a surgical procedure may exist. The academic status of the institution did not affect the outcomes of these patients.

Hospital volume allocation: integrating decision maker and patient perspectives.

Planning problems in healthcare systems have received greater attention in the last decade, especially because of the concerns recently raised about the scattering of surgical interventions among a wide number of different facilities that can undermine the quality of the outcome due to the volume-outcome association. In this paper, an approach to plan the amount of surgical interventions that a facility has to perform to assure a low adjusted mortality rate is proposed. The approach explicitly takes into account the existing interaction among patients' choices and decision makers' planning decisions. The first objective of the proposed approach is to find a solution able to reach quality in health outcomes and patients' adherence. The second objective is to investigate the difference among solutions that are identified as optimal by either only one of the actors' perspective, i.e., decision makers and patients, or by considering both the perspectives simultaneously. Following these objectives, the proposed approach is applied to a case study on Italian colon cancer interventions performed in 2014. Results confirm a variation in the hospital planned volumes when considering patients' behaviour together with the policy maker plan, especially due to personal preferences and lack of information about hospital quality.

Exploring relationships between in-hospital mortality and hospital case volume using random forest: results of a cohort study based on a nationwide sample of German hospitals, 2016-2018.

BACKGROUND: Relationships between in-hospital mortality and case volume were investigated for various patient groups in many empirical studies with mixed results. Typically, those studies relied on (semi-)parametric statistical models like logistic regression. Those models impose strong assumptions on the functional form of the relationship between outcome and case volume. The aim of this study was to determine associations between in-hospital mortality and hospital case volume using random forest as a flexible, nonparametric machine learning method. METHODS: We analyzed a sample of 753,895 hospital cases with stroke, myocardial infarction, ventilation > 24 h, COPD, pneumonia, and colorectal cancer undergoing colorectal resection treated in 233 German hospitals over the period 2016-2018. We derived partial dependence functions from random forest estimates capturing the relationship between the patient-specific probability of in-hospital death and hospital case volume for each of the six considered patient groups. RESULTS: Across all patient groups, the smallest hospital volumes were consistently related to the highest predicted probabilities of in-hospital death. We found strong relationships between in-hospital mortality and hospital case volume for hospitals treating a (very) small number of cases. Slightly higher case volumes were associated with substantially lower mortality. The estimated relationships between in-hospital mortality and case volume were nonlinear and nonmonotonic. CONCLUSION: Our analysis revealed strong relationships between in-hospital mortality and hospital case volume in hospitals treating a small number of cases. The nonlinearity and nonmonotonicity of the estimated relationships indicate that studies applying conventional statistical approaches like logistic regression should consider these relationships adequately.