Minimum Case Volume Research Articles

Advancing minimally invasive hepato-pancreato-biliary surgery: ensuring safety with implementation.

Although minimally invasive hepato-pancreato-biliary (MIS HPB) surgery can be performed with good outcomes, there are currently no standardized requirements for centers or surgeons who wish to implement MIS HPB surgery. The aim of this study was to create a consensus statement regarding safe dissemination and implementation of MIS HPB surgical programs. Sixteen key questions regarding safety in MIS HPB surgery were generated after a focused literature search and iterative review by three field experts. Participants for the working group were then selected using sequential purposive sampling and snowball techniques. Review of the 16 questions took place over a single 2-h meeting. The senior author facilitated the session, and a modified nominal group technique was used. Twenty three surgeons were in attendance. All participants agreed or strongly agreed that formal guidelines should exist for both institutions and individual surgeons interested in implementing MIS HPB surgery and that routine monitoring and reporting of institutional and surgeon technical outcomes should be performed. Regarding volume cutoffs, most participants (91%) agreed or strongly agreed that a minimum annual institutional volume cutoff for complex MIS HPB surgery, such as major hepatectomy or pancreaticoduodenectomy, should exist. A smaller proportion (74%) agreed or strongly agreed that a minimum annual surgeon volume requirement should exist. The majority of participants agreed or strongly agreed that surgeons were responsible for defining (100%) and enforcing (78%) guidelines to ensure the overall safety of MIS HPB programs. Finally, formal MIS HPB training, minimum case volume requirements, institutional support and infrastructure, and mandatory collection of outcomes data were all recognized as important aspects of safe implementation of MIS HPB surgery. Safe implementation of MIS HPB surgery requires a thoughtful process that incorporates structured training, sufficient volume and expertise, a proper institutional ecosystem, and monitoring of outcomes.

Dynamic volume-outcome association for esophagectomies: Do current volume thresholds still apply?

BackgroundIt is unknown if the current minimum case volume recommendation of 20 cases per year per hospital is applicable to contemporary practice. MethodsPatients undergoing esophageal resection between 2005 and 2015 were identified in the National Cancer Database. High, medium, and low-volume hospital strata were defined by quartiles. Adjusted odds ratios and adjusted 30-day mortality between low-, medium-, and high-volume hospitals were calculated using logistic regression analyses and trended over time. ResultsOnly 1.1% of hospitals had ≥20 annual cases. The unadjusted 30-day mortality for esophagectomy was 3.8% overall. Unadjusted and adjusted 30-day mortality trended down for all three strata between 2005 and 2015, with disproportionate decreases for low-volume and medium-volume versus high-volume hospitals. By 2015, adjusted 30-day mortality was similar in medium- and high-volume hospitals (odds ratio 1.35, 95% confidence interval 0.96–1.91). For hospitals with 20 or more annual cases the adjusted 30-day mortality was 2.7% overall. To achieve this same 30-day mortality the minimum volume threshold had lowered to 7 annual cases by 2015. ConclusionOnly 1.1% of hospitals meet current volume recommendations for esophagectomy. Differential improvements in postoperative mortality at low- and medium- versus high-volume hospitals have led to 7 cases in 2015 achieving the same adjusted 30-day mortality as 20 cases in the overall cohort. Lowering volume thresholds for esophagectomy in contemporary practice would potentially increase the proportion of hospitals able to meet volume standards and increase access to quality care without sacrificing quality.

Assessing the State of Training in Congenital Interventional Cardiology: A Global Survey of Program Directors.

This study aimed to evaluate the current state of congenital interventional cardiology training worldwide, with a focus on case volumes, competency assessment, and the need for ongoing mentorship during early career stages. A survey was conducted among program directors (PDs) of congenital interventional training programs across the globe. The survey gathered data on training pathways, case volumes, types of procedures performed, trainee competency assessment, and the role of ongoing mentorship. Of the 79 PDs who completed the survey, it was observed that training pathways and case volumes varied significantly, particularly between the United States and other countries. Most PDs reported an annual laboratory case volume of >500 congenital cardiac cases, with most cases being interventional. While trainees demonstrated competency in simple procedures (diagnostic cases, simple ASD closure), complex interventions (such as patent ductus arteriosus closure in premature infants) require ongoing mentorship for graduates. PDs recommended a minimum case volume of 400 total cases for trainees, including 250 interventional cases. In addition to case volumes, assessing trainee competency was deemed important, with clinical reasoning, judgment, skillset, teamwork, and complication management being key areas of evaluation. The study highlights the variability in congenital interventional cardiology training and the need for ongoing mentorship during the early career years. External mentorship programs, facilitated by national and international societies, are proposed to provide critical support for early career interventionalists thus enhancing patient care for congenital heart disease. Ultimately, the findings of this survey may serve as a framework for future training standards and guidelines in this specialized field.

Prevalence of carpal tunnel syndrome symptoms among neurosurgical spine surgeons

BackgroundNeurosurgeons, particularly spine surgeons, have high exposure to vibrations via electric or pneumatic drills and repetitive motion. Although no data exist for the prevalence of carpal tunnel syndrome (CTS) among these surgeons, anecdotal evidence suggests the rate of symptoms is higher than in the general population. MethodsAn anonymous questionnaire was developed to assess demographics, practice patterns, presence of CTS symptoms, and treatment (time off, bracing, medication, injections, surgery). The survey was sent via anonymous email link to members of the AANS/CNS Joint Section on Disorders of the Spine and Peripheral Nerve. Results101 members responded: 44 reported at least one symptom related to CTS (43.6%). There was no statistically significant relationship between overall or spine case volume, the number of cases performed annually/daily, and CTS symptoms. Respondents working in non-teaching settings were significantly more likely to have CTS symptoms than academic teaching institutions (50.0% v. 45.0%; p = 0.0112). ConclusionsOur survey demonstrated CTS to be more prevalent in spine neurosurgeons (43.6%) than in the general population (1–5%). The lack of significant association between most practice-based metrics and CTS symptoms may indicate that respondents have a minimum case volume that exceeds the amount of vibration exposure/repetitive motion to develop symptoms. The significantly increased prevalence of CTS among neurosurgeons at non-teaching institutions suggests that residents provide operative assistance offsetting the vibration exposure/repetitive motion by attendings. Further research may determine the root cause for the high prevalence of CTS in spine neurosurgeons and devise methods for reducing vibration exposure.

Operative Case Volumes and Variation for General Surgery Training in East, Central, and Southern Africa

BackgroundOperative experience is a necessary part of surgical training. The College of Surgeons of East, Central, and Southern Africa (COSECSA), which oversees general surgery training programs in the region, has implemented guidelines for the minimum necessary case volumes upon completion of two (Membership) and five (Fellowship) years of surgical training. We aimed to review trainee experience to determine whether guidelines are being met and examine the variation of cases between countries.MethodsOperative procedures were categorized from a cohort of COSECSA general surgery trainees and compared to the guideline minimum case volumes for Membership and Fellowship levels. The primary and secondary outcomes were total observed case volumes and cases within defined categories. Variations by country and development indices were explored.ResultsOne hundred ninety-four trainees performed 69,283 unique procedures related to general surgery training. The review included 70 accredited hospitals and sixteen countries within Africa. Eighty percent of MCS trainees met the guideline minimum of 200 overall cases; however, numerous trainees did not meet the guideline minimum for each procedure. All FCS trainees met the volume target for total cases and orthopedics; however, many did not meet the guideline minimums for other categories, especially breast, head and neck, urology, and vascular surgery. The operative experience of trainees varied significantly by location and national income level.ConclusionsSurgical trainees in East, Central, and Southern Africa have diverse operative training experience. Most trainees fulfill the overall case volume requirements; however, further exploration of how to meet the demands of specific categories and procedures is necessary.

Impact of institutional case volume of solid organ transplantation on patient outcomes and implications for healthcare policy in Korea.

Solid organ transplantation is distinguished from other high-risk surgical procedures by the fact that it utilizes an extremely limited and precious resource and requires a multidisciplinary team approach. For several decades, institutional experience, as quantified by center volume, has been shown to be strongly associated with patient outcomes and graft survival after solid organ transplantation. The United States has implemented a minimum case volume requirement and performance standards for accreditation as a validated transplantation center. Solid organ transplantation in Europe is also governed by the European Union, which monitors patient outcomes and organ allocation. The number of solid organ transplantation cases in Korea is increasing, with patient outcomes comparable to international standards. However, Korea has outdated regulations regarding hospital facilities, and performance indicators including patient outcomes after transplantation are not monitored. Therefore, centers perform solid organ transplantation with no meaningful oversight. In this review, data regarding the impact of institutional case volume of kidney, liver, lung, and heart transplantation are summarized, followed by a description of current transplantation center regulations in the United States and Europe. The basis for the necessity of adequate transplantation center regulations in Korea is presented.

Surgical Treatment of Esophageal Cancer-New Technologies, Modern Concepts

Das Ösophaguskarzinom wird in Deutschland meist in spezialisierten Zentren entsprechend den Leitlinien multimodal und interdisziplinär therapiert. In den kommenden Jahren wird die Zentralisierung der Ösophaguschirurgie in Deutschland durch die Festlegung neuer Mindestmengen weiter voranschreiten. Dieser Artikel soll neue Technologien für die chirurgische Therapie des Ösophaguskarzinoms und zudem aktuelle onkologische Konzepte aus der Sicht eines High-volume-Centers vorstellen.

Minimum case volume regulations of the Federal Joint Committee : Mode of function and application in practice

The minimum case volume regulations of the Federal Joint Committee determine the size of the respective annual minimum number for each site of a hospital, for selected scheduled inpatient services where the quality of the treatment results is dependent on the number of services carried out. In addition, further details on the elucidation of the prognosis are determined in the regulations. Due to the legally defined prognostic procedure as a prerequisite for a prospective justification for service provision, new or altered minimum case volumes come into effect even before the end of the validity period established on the justification for provision of services. The Federal Joint Committee established this basic principle also for the introduction procedure in a resolution from 16 December 2021. This article explains the background and should support the implementation.

Chirurgische Therapie des Ösophaguskarzinoms – neue Technologien, moderne Konzepte

Das Ösophaguskarzinom wird in Deutschland meist in spezialisierten Zentren entsprechend den Leitlinien multimodal und interdisziplinär therapiert. In den kommenden Jahren wird die Zentralisierung der Ösophaguschirurgie in Deutschland durch die Festlegung neuer Mindestmengen weiter voranschreiten. Dieser Artikel soll neue Technologien für die chirurgische Therapie des Ösophaguskarzinoms und zudem aktuelle onkologische Konzepte aus der Sicht eines High-volume-Centers vorstellen.

Abstract 14234: Stroke Center Volume, Not Accreditation Status, is Associated With Outcomes of Stroke Patients Treated by Mechanical Thrombectomy

Introduction: In the USA, endovascular capable stroke centers (ECC) that perform mechanical thrombectomy (MT) for large vessel stroke can be accredited by a number of agencies. However, there remains little evidence on recommendations for minimum case volume required for centers to maintain competency. Hypothesis: Clinical outcomes (namely hospital mortality and home discharge disposition) of stroke patients treated by MT are associated with center volume but not accreditation status. Methods: We obtained nationwide MedPAR data from the Center for Medicare and Medicaid Services (CMS) for 2017 and 2018. Endovascular MT cases were identified using ICD 10 codes. A list of ECCs was obtained from the Joint Commission, HFAP, DNV, and State Health Departments and was cross-referenced with a list of accredited centers. Independent t-tests were used to compare the mean rates of mortality and home discharge between accredited and non-accredited centers. Pearson’s correlation was used to test the association of annual case volume (in 10 groups in logarithmic increments from minimum to maximum) with the rates of mortality and home discharge. Results: In 2017 and 2018, we identified 29,536 cases of MT that were performed at 847 centers (of which 354 were accredited) across the USA. There was no significant difference between accredited and non-accredited centers with regard to hospital mortality (14.8% vs. 14.5%, p-value=0.34) and home discharge disposition (12.1% vs. 12.0%, p-value=0.78). Hospital mortality was significantly negatively correlated with center volume (r=-0.83, 95%CI=-0.96 to -0.44, p-value=0.003), whereas home discharge disposition was significantly positively correlated with center volume (r=0.68, 95%CI=0.09 to 0.92, p-value=0.030). Conclusions: Accreditation showed no correlation to clinical outcomes. However, increasing volume of MT cases in ECCs correlated to increasing mortality and decreasing rate of home discharge.

Surgical treatment of esophageal cancer-New technologies, modern concepts

Das Ösophaguskarzinom wird in Deutschland meist in spezialisierten Zentren entsprechend den Leitlinien multimodal und interdisziplinär therapiert. In den kommenden Jahren wird die Zentralisierung der Ösophaguschirurgie in Deutschland durch die Festlegung neuer Mindestmengen weiter voranschreiten. Dieser Artikel soll neue Technologien für die chirurgische Therapie des Ösophaguskarzinoms und zudem aktuelle onkologische Konzepte aus der Sicht eines High-volume-Centers vorstellen.

Are Esophagectomy Board Requirements Achievable? A Multi-Institutional Analysis

Duty-hour restrictions have implications on trainee operative exposure necessary to meet minimum case-volume requirements. We utilized a previously validated simulation model to evaluate the effect of program volume, trainee numbers and complement, and rotation schedule on the probability of achieving adequate esophagectomy case numbers for cardiothoracic surgery trainees. A ProModel simulator centered on probabilistic distributions of operative cases was utilized. Historical data from five 2-year cardiothoracic surgery training programs were obtained from 2016-2018 and used as inputs to the simulator that generated 10,000 "trainee 2-year periods" per program. Programs varied in annual average esophagectomy volume (12-91 per year), with 2-4 trainees graduating over a 2-year training period. If esophagectomy cases were distributed solely based on scheduling and institutional volume, only 60% of evaluated programs could adequately expose all trainees in esophagectomy to meet case requirements. The 3 programs with adequate esophagectomy volumes had averaged 3.3 times (range 3.0-3.6) the minimum number of board-required cases for their programs' trainees. The ability of programs to provide trainees with adequate esophagectomy volume is challenging based on institutional volume and scheduling. Through simulation, we demonstrate that programs need >2 times the expected minimum number of esophagectomies to ensure that >90% of trainees meet case-volume requirements. Programs may consider strategies such as allowing trainees to select cases based on personal need, train fewer fellows, or enable trainees to seek subspecialty exposure externally to achieve minimum esophagectomy case-load requirements.

Differences in therapy and survival between lung cancer patients treated in hospitals with high and low patient case volume

BackgroundIn light of political discussions about minimum case volumes and certified lung cancer centers, this observational study investigates differences in therapy and survival between high vs. low patient volume hospitals (HPVH vs. LPVH). MethodsWe identified 12,374 lung cancer patients treated in HPVH (>67 patients) and LPVH in 2013 from German health insurance claims. Stratified by metastasis status (no metastases, nodal metastases, systemic metastases), we compared HPVHs and LPVHs regarding likelihood of resection and systemic therapy, type of systemic therapy, and surgical outcomes, using multivariate logistic models. Three-year survival was modeled using Cox regression. We adjusted all regression models for age, gender, comorbidity, and residence area, and included a cluster variable for the hospital. ResultsAround 24 % of patients were treated in HPVHs. Irrespective of stratum and subgroup, three-year survival was significantly better in HPVHs. In patients with systemic metastases (OR = 1.84, CI=[1.22,2.76]) and without metastases (OR = 3.28, CI=[2.13, 5.04]), resection was more likely in HPVHs. Among patients with systemic therapy, the odds of receiving pemetrexed was higher in HPVHs, in patients with nodal metastases (OR = 1.57, CI=[1.01,2.45]). In resected patients without metastases the odds ratio of receiving a thoracoscopic lobectomy was 2.28 (CI=[1.04,4.99]) in HPVHs. ConclusionOur data suggests that case volume is clinically relevant in resected and non-resected lung cancer patients, but optimal minimum case volumes may differ for subgroups.

Association between institutional case volume and mortality following thoracic aorta replacement: a nationwide Korean cohort study

BackgroundThe inverse relationship between case volume and postoperative mortality following high-risk surgical procedures have been reported. Thoracic aorta surgery is associated with one of the highest postoperative mortality. The relationship between institutional case volume and postoperative mortality in patients undergoing thoracic aorta replacement surgery was evaluated.MethodsAll thoracic aorta replacement surgeries performed in Korea between 2009 and 2016 in adult patients were analyzed using an administrative database. Hospitals were divided into low (< 30 cases/year), medium (30–60 cases/year), or high (> 60 cases/year) volume centers depending on the annual average number of thoracic aorta replacement surgeries performed. The impact of case volume on in-hospital mortality was assessed using the logistic regression.ResultsAcross 83 hospitals, 4867 cases of thoracic aorta replacement were performed. In-hospital mortality was 8.6% (191/2222), 10.7% (77/717), and 21.9% (422/1928) in high, medium, and low volume centers, respectively. The adjusted risk of in-hospital mortality was significantly higher in medium (odds ratio [OR], 1.56; 95% confidence interval [CI], 1.16–2.11, P = 0.004) and low volume centers (OR, 3.12; 95% CI, 2.54–3.85, P < 0.001) compared to high volume centers.ConclusionsPatients who had underwent thoracic aorta replacement surgery in lower volume centers had increased risk of in-hospital mortality after surgery compared to those in higher volume centers. Our results may provide the basis for minimum case volume requirement or regionalization in thoracic aorta replacement surgery for optimal patient outcome.

Operative Case Volume Minimums Necessary for Surgical Training Throughout Rural Africa.

Resident operative case volumes are an important aspect of surgical education, and minimums are required in Accreditation Council for Graduate Medical Education (ACGME) programs. Minimum operative case volumes for training do not exist in rural Africa. Our objective was to determine the optimal minimum operative case volume necessary for general surgery training in rural Africa. A cross-sectional census electronic survey was conducted among faculty (N = 24) and graduates (N = 56) of Pan-African Academy of Christian Surgeonstraining programs. Three equally weighted exposures (median minimum case volume suggested by participants, operative experience of prior graduates, and comparisons with ACGME minimums), adjusted from responses to targeted questions, were utilized to construct an optimal minimum operative case volume for training. Sixty-four surgeons were contacted and 40 (13 faculty, 24 graduates, and 3 graduates who became faculty) participated. All participants thought operative case minimums were necessary, and the majority (98%) felt current training adequately prepared surgeons for their setting. Constructed optimal case volumes included 1000 major cases with fewer required cases than ACGME in abdomen, breast, thoracic, vascular, endoscopy, and laparoscopy and more required cases than ACGME for alimentary tract, endocrine, operative trauma, skin and soft tissue, pediatric, and plastic surgery. Other categories (gynecology, orthopedics, and urology) were deemed necessary for surgical training, with regional differences. Prior graduates satisfied the overall, but not category-specific, proposed minimums. The surveyed surgeons highlighted the need for diverse surgical training with minimum exposures. They described increased need for cases reflecting regional variations with a desire for more experience in categories less common at their institutions.

Correlation of Proposed Surgical Volume Standards for Complex Cancer Surgery with Hospital Mortality

Minimum case volume thresholds for complex cancer operations have been proposed by the Leapfrog Group. There has been no formal study of how these standards correlate with actual hospital mortality. The National Cancer Database was used to identify patients undergoing operations for esophageal, lung, pancreatic, and rectal cancer between 2013 and 2015. Recommended annual hospital case volume was used to divide hospitals into those meeting a minimum volume threshold (VT) and those below it. Hospitals in the highest quartile of adjusted hospital mortality were designated as poor performing hospitals (PPHs). Sensitivity, specificity, negative predictive value, and positive predictive value of current minimum VTs to predict PPHs were calculated. The proportion of hospitals meeting minimum VTs varied from 7% for esophagectomy to 27% for rectal operations. Proposed minimum VTs had a sensitivity of 69% to 93%, specificity of 7% to 27%, and area under the curve of 0.59 to 0.65 for identifying PPHs. Although the negative predictive value varied from 72% to 79%, the positive predictive value was only 24% to 26%. Optimal minimum VTs to identify PPHs were lower than those currently proposed-esophagus was 4 vs 20, lung was 21 vs 40, pancreas was 7 vs 20, and rectum was 8 vs 16. Even under these idealized volume cutoffs, the best performing procedure-specific model (esophagus) had an area under the curve of 0.68. Although proposed minimum VTs are reasonably good at identifying PPHs, they misclassify 3 of 4 hospitals below the minimum VT as PPHs and 1 of 4 PPHs as meeting the minimum VT. Use of case volume cutoffs alone does not correlate well with actual hospital mortality.

Surgeon experience association with patient selection and outcomes after open abdominal aortic aneurysm repair

BackgroundGrowing calls for guidelines advocating minimum annual case volumes for surgeon credentialing remain controversial. Although most attention to date has focused on the impact of obligatory case volume, less attention has been devoted to the more complex association between surgeon years of independent practice experience and procedure outcomes after open abdominal aortic aneurysm repair (OAR). Therefore, the purpose of this study was to explore the association of surgeon experience with case selection and real-world outcomes after OAR. MethodsAll Society for Vascular Surgery-Vascular Quality Initiative infrarenal and juxtarenal OARs (n = 11,900; 71% elective; 29% nonelective) from 2003 to 2019 were examined. Surgeon experience was defined by years in practice after training completion. Experience level at time of repair was categorized (≤5 years, n = 1048; 6-10 years, n = 1309; 11-15 years, n = 1244; and ≥16 years, n = 4772) and intergroup univariate comparisons were made. Logistic regression identified independent predictors of complications, 30-day death, and 1-year mortality. Models were constructed with or without surgeon experience strata to determine association with outcomes. ResultsIncreasing surgeon experience was associated with performing greater proportions of elective procedures, whereas less experienced surgeons had disproportionate exposure to nonelective operations (elective, 73% ≥16 years vs 62% ≤5 years [P < .0001]; nonelective, ≤5 years, 38% vs 27%, ≥16-years [P < .0001]). Among surgeons who perform five or fewer cases per year, the risk of any aggregate major complication after elective OAR decreased significantly as experience increased (P = .0004), although no differences were detected in nonelective cases or among higher volume surgeons. Similarly, the risk of in-hospital death decreased with increasing experience (P = .004), but only among low-volume surgeons performing elective procedures. Comorbidities were similar across all experience strata for both elective and nonelective presentations; however, more experienced surgeons operated on higher proportions of nonelective patients with coronary disease (P = .04). Early career surgeons more frequently operated on patients with American Society of Anesthesiologists IV designation, larger abdominal aortic aneurysm diameters and used suprarenal/celiac cross-clamps more frequently than later career surgeons. The 1-year survival after elective and nonelective OAR was not impacted by surgeon experience (Ptrend > .15 for all comparisons). ConclusionsIncreasing surgeon years of practice experience correlated significantly with a reduced risk of developing multiple postoperative complications, including postoperative death in the elective setting. Surgeons within their first 5 years of practice are exposed to greater proportions of nonelective cases but seem to have similar outcomes after these repairs compared with surgeons with more experience. Notably, surgeons in their first 5 years of practice operate on more complex elective patients as underscored by higher aggregate comorbidity scores, larger aneurysm diameters, and need for suprarenal aortic cross-clamping. These data have important implications on training paradigms, faculty recruitment, and the organization of mentorship when on boarding new surgeons.

A Pilot Study on Diagnostic Radiology Residency Case Volumes From a Canadian Perspective: A Marker of Resident Knowledge.

New guidelines from the Accreditation Council for Graduate Medical Education (ACGME) have proposed minimum case volumes to be obtained during residency. While radiology residency programs in Canada are accredited by the Royal College of Physicians and Surgeons of Canada, there are currently no minimum case volumes standards for radiology residency training in Canada. New changes in residency training throughout Canada are coming in the form of competency-based medical education. Using data from a pilot study, this article examines radiology resident case volumes among recently graduated cohorts of residents and determines whether there is a correlation between case volumes and measures of resident success. Resident case volumes for 3 cohorts of graduated residents (2016-2018) were extracted from the institutional database. Achievement of minimum case volumes based on the ACGME guidelines was performed for each resident. Pearson correlation analysis (n = 9) was performed to examine the relationships between resident case volumes and markers of resident success including residents' relative knowledge ranking and their American College of Radiology (ACR) in-training exam scores. A statistically significant, positive correlation was observed between residents' case volume and their relative knowledge ranking (r = 0.682, P < .05). Residents' relative knowledge ranking was also statistically significant and positively correlated with their ACR in-training percentile score (r = 0.715, P < .05). This study suggests that residents who interpret more cases are more likely to demonstrate higher knowledge, thereby highlighting the utility of case volumes as a prognostic marker of resident success. As well, the results underscore the potential use of ACGME minimum case volumes as a prognostic marker. These findings can inform future curriculum planning and development in radiology residency training programs.

Impact of mitral valve repair case volume on postoperative mortality: a population-based observational study

Introduction Although mitral valve repair is recommended over replacement when feasible due to its better outcomes, repair rates vary remarkably between cardiac surgery centers. The aim of this study is to examine the effect of institutional case volume on mortality after mitral valve repair. Methods We analyzed all cases of adult mitral valve repair performed in Korea between 2007 and 2016 using administrative data. The association between case volume and 1-year mortality after mitral valve repair was analyzed after categorizing centers depending on the number of mitral valve repairs performed; low- ( 20 and 40 cases/year, reference) volume centers. The effect of case volume on cumulative all-cause mortality was also assessed. Results A total of 6041 cases were performed in 86 centers. One-year mortality was 10.1% (175/1728), 8.7% (93/1067), and 4.7% (153/3246) in low-, medium-, and high-volume centers, respectively. Low- and medium-volume centers showed increased risk of 1-year mortality compared to high-volume centers (OR [95% CI]; 2.80 [2.15–3.64] and 2.66 [1.94–3.64], respectively.). The risk of cumulative all-cause mortality of up to 10 years was also worse in low- and medium-volume centers (HR [95% CI]; 1.96 [1.68–2.29] and 1.77 [1.47–2.12], respectively.). Discussion Lower case-volume was associated with higher risk of mortality after mitral valve repair. A minimum case volume may be required for hospitals performing mitral valve repair to guarantee adequate patient outcome.

Poisson Probability of Failing to Meet Minimum Case Volumes in Pediatric Surgery Fellowships.

With the expansion of pediatric surgery fellowships from 2008 to 2018, there is concern for the dilution of training experience, especially for rare index cases. The Accreditation Council for Graduate Medical Education (ACGME) established required minimum case numbers by case type, but this is a program requirement rather than an individual trainee requirement. The American Board of Surgery (ABS) is considering instituting minimum case requirements across 5 broad categories for individuals to be board-eligible in pediatric surgery. The ACGME National Data Report summary case logs were obtained for graduating fellows in pediatric surgery from 2008 to 2018. Median case volumes were compared to minimum ACGME case numbers and proposed ABS individual requirements. Using Poisson distributions, probabilities of individual fellows failing to meet minimum case numbers were calculated. The average annual probability that a median program would fail to meet minimum ACGME case numbers in at least 1 category was estimated at 16.6%. Using the proposed ABS system, the probability of failure was estimated at 44.1%. No temporal trend was found in the annual probability of failure in either the ACGME or the proposed ABS system. There is significant risk of a fellow failing to meet case minimums in the ACGME system and the proposed ABS system. This probability is increased for the half of programs below median. If the ABS institutes case minimums as a requirement for certification in pediatric surgery, the current training paradigm may be impacted at some programs.