The combined effects of hospital and surgeon volume on short-term survival after hepatic resection in a population-based study

Practice patterns of hepatobiliary surgery within the military

BACKGROUND

The purpose of this study is to evaluate the trends of hepatobiliary surgeries performed at military hospitals and to discuss potential implications on resident training and military readiness. While there is data to suggest centralization of surgical specialty services leads to improved patient outcomes, the military does not currently have a specific centralization policy. Implementation of such a policy could potentially impact resident training and readiness of military surgeons. Even in the absence of such a policy, there may still be a trend toward centralization of more complex surgeries like hepatobiliary surgeries. The present study evaluates the numbers and types of hepatobiliary procedures performed at military hospitals.

METHODS

This study is a retrospective review of de-identified data from Military Health System Mart (M2) from 2014 to 2020. The M2 database contains patient data from all Defense Health Agency treatment facilities, encompassing all branches of the United States Military. Variables collected include number and types of hepatobiliary procedures performed and patient demographics. The primary endpoint was the number and type of surgery for each medical facility. Linear regression was used to evaluate significant trends in numbers of surgeries over time.

RESULTS

Fifty-five military hospitals performed hepatobiliary surgeries from 2014 to 2020. A total of 1,087 hepatobiliary surgeries were performed during this time; cholecystectomies, percutaneous procedures, and endoscopic procedures were excluded. There was no significant decrease in overall case volume. The most commonly performed hepatobiliary surgery was "unlisted laparoscopic liver procedure." The military training facility with the most hepatobiliary cases was Brooke Army Medical Center.

CONCLUSION

The number of hepatobiliary surgeries performed in military hospitals has not significantly decreased over the years 2014-2020, despite a national trend toward centralization. Centralization of hepatobiliary surgeries in the future may impact residency training as well as military medical readiness.

5-year recurrence prediction after hepatocellular carcinoma resection: deep learning vs. Cox regression models

Deep learning algorithms have yet to be used for predicting clinical prognosis after cancer surgery. Therefore, this study compared performance indices and permutation importance of potential confounders in three models for predicting 5-year recurrence after hepatocellular carcinoma (HCC) resection: a deep-learning deep neural network (DNN) model, a recurrent neural network (RNN) model, and a Cox proportional hazard (CPH) regression model. Data for 725 patients who had received HCC resection at three medical centers in southern Taiwan between April, 2011, and December, 2015, were randomly divided into three datasets: a training dataset containing data for 507 subjects was used for model development, a testing dataset containing data for 109 subjects was used for internal validation, and a validating dataset containing data for 109 subjects was used for external validation. Feature importance analysis was also performed to identify potential predictors of recurrence after HCC resection. Univariate Cox proportional hazards regression analyses were performed to identify potential significant predictors of 5-year recurrence after HCC resection, which were included in the forecasting models (P < 0.05). All performance indices for the DNN model were significantly higher than those for the RNN model and the conventional CPH model (P < 0.001). The most important potential predictor of 5-year recurrence after HCC resection was surgeon volume followed by, in order of importance, hospital volume, preoperative Beck Depression Scale score, preoperative Beck Anxiety Scale score, co-residence with family, tumor stage, and tumor size. The feature importance analysis performed to investigate interpretability in this study elucidated the potential use of deep learning models for predicting recurrence after HCC resection and for identifying predictors of recurrence. Further experiments using the proposed DNN model would clarify its potential uses for developing, promoting, and improving health policies for treating HCC patients after surgery.

Evaluation of Safety-Related Outcomes of One-Segment and More-Than-One-Segment High-Level Hepatectomy in Hepatocellular Carcinoma Based on the Japanese Board Certification System

Background

We evaluated the impact of the Japanese board certification system for expert surgeons (JBCSES) on complications and survival outcomes in hepatectomy for hepatocellular carcinoma.

Methods

The postoperative outcomes of 493 patients who underwent high-level liver surgery involving one-segment (OSeg) hepatectomy and more-than-one-segment (MOSeg) resection were compared before and after JBCSES establishment. After the establishment of the JBCSES, the patients’ postoperative outcomes were compared using propensity score matching (PSM) to determine the influence of expert surgeons.

Results

The establishment of the JBCSES was associated with a decrease in the overall postoperative complication rates after high-level liver surgery from 50.2 to 38.1% (P = 0.008) and a decrease in Clavien–Dindo class ≥ IIIb complications from 10.2 to 5.0% (P = 0.035). The 90-day mortality rate decreased from 5.1 to 0.7% (P = 0.003), and the 5-year survival rate increased from 51.4 to 63.9% (P = 0.009). Using PSM, a comparison of OSeg hepatectomies that involved expert surgeons (n = 48) and those that did not (n = 48) showed significantly lower intraoperative blood loss in surgeries involving an expert surgeon (mean, 340 vs. 473 mL; P = 0.033). There were no significant differences in complication rates or long-term prognosis between these groups. A comparison of MOSeg hepatectomies that involved expert surgeons (n = 26) and those that did not (n = 26) showed no significant difference in surgical factors, complications, or overall survival between the two groups.

Conclusions

After establishment of the JBCSES, postoperative complication rates and mortality rates decreased and survival rates increased following liver surgery. Expert surgeon participation significantly decreased intraoperative blood loss during OSeg hepatectomies.

County-Level Variation in Utilization of Surgical Resection for Early-Stage Hepatopancreatic Cancer Among Medicare Beneficiaries in the USA

INTRODUCTION

Geographic variations in access to care exist in the USA. We sought to characterize county-level disparities relative to access to surgery among patients with early-stage hepatopancreatic (HP) cancer.

METHODS

Data were extracted from the Surveillance, Epidemiology, and End Results (SEER)-Medicare Linked database from 2004 to 2015 to identify patients undergoing surgery for early-stage HP cancer . County-level information was acquired from the Area Health Resources Files (AHRF). Multivariable logistic regression analysis was performed to assess factors associated with utilization of HP surgery on the county level.

RESULTS

Among 13,639 patients who met inclusion criteria, 66.9% (n = 9125) were diagnosed with pancreatic cancer and 33.1% (n = 4514) of patients had liver cancer. Among patients diagnosed with early-stage liver and pancreas malignancy, two-thirds (n = 8878, 65%) underwent surgery. Marked county-level variation in the utilization of surgery was noted among patients with early-stage HP cancer ranging from 57.1% to more than 83.3% depending on which county a patient resided. After controlling for patient and tumor-related characteristics, counties with the highest quartile of patients living below the poverty level had 35% lower odds of receiving surgery for early stage HP cancer compared patients who lived in a county with the lowest proportion of patients below the poverty line (OR 0.65, 95% CI 0.55-0.77). In addition, patients residing in counties with the highest surgeon-to-population ratio (OR 2.01, 95% CI 1.52-2.65), as well as the highest hospital bed-to-population ratio (OR 1.29, 95% CI 1.07-1.54), were more likely to undergo surgical treatment for an early-stage HP malignancy.

CONCLUSION

Area-level variations among patients undergoing surgery for early-stage HP cancer were mainly due to differences in structural measures and county-level factors. Policies targeting high-poverty counties and improvement in structural measures may reduce variations in utilization of surgery among patients diagnosed with early-stage HP cancer.

Facility volume-survival relationship in patients with early-stage pancreatic adenocarcinoma treated with neoadjuvant chemotherapy followed by pancreatoduodenectomy

BACKGROUND

There is evidence that neoadjuvant therapy is associated with improved survival compared with upfront pancreatectomy for pancreatic adenocarcinoma. Treatment at high-volume pancreatic surgery centers is associated with improved short-term postoperative outcomes compared with low-volume centers. We compared overall survival of patients with early-stage pancreatic adenocarcinoma who received neoadjuvant therapy before resection stratified by facility volume.

METHODS

Patients with clinical T0 to T2 pancreatic adenocarcinoma who received neoadjuvant therapy before pancreatoduodenectomy were identified in the National Cancer Database (2010-2016). High-volume pancreatic surgery centers performed ≥36 pancreatectomies/year. Patients were matched 1:1 by propensity score. Pathologic outcomes, postoperative outcomes, and overall survival were compared.

RESULTS

Before matching, 1,449 patients were treated at low-volume centers and 250 at high-volume pancreatic surgery centers. After matching, there were 177 patients per group. High-volume pancreatic surgery centers were more commonly academic/research facilities (99.4% vs 54.0%; P < .001), and patients traveled greater distances (65 vs 13 miles; P < .001). Time from diagnosis to neoadjuvant therapy and surgery was similar. Treatment at high-volume pancreatic surgery centers was associated with shorter duration of stay (7 vs 8 days; P = .003) and lower 90-day mortality rate after pancreatoduodenectomy (0.0% vs 5.0%; P = .01). Patients treated at high-volume pancreatic surgery centers had improved overall survival (36.3 vs 29.4 months; P = .03; hazard ratio 0.73). On subset analysis of academic/research facilities, high-volume pancreatic surgery centers remained associated with shorter duration of stay, lower 90-day mortality, and greater overall survival.

CONCLUSION

The majority of patients treated with neoadjuvant therapy for early-stage pancreatic adenocarcinoma received care at low-volume centers. Treatment at high-volume pancreatic surgery centers was associated with improved overall survival and short-term postoperative outcomes.

Effects of volume on outcome in hepatobiliary surgery: a review with guidelines proposal

The positive relationship between volume and outcome in hepatobiliary surgery has been demonstrated for many years. As for other complex surgical procedures, both improved short- and long-term outcomes have been associated with a higher volume of procedures. However, whether the centralization of complex hepatobiliary procedures makes full sense because it should be associated with higher quality of care, as reported in the literature, precise criteria on what to centralize, where to centralize, and who should be entitled to perform complex procedures are still missing. Indeed, despite the generalized consensus on centralization in hepatobiliary surgery, this topic remains very complex because many determinants are involved in such a centralization process, of which some of them cannot be easily controlled. In the context of different health systems worldwide, such as national health systems and private insurance, there are different stakeholders that demand different needs: politicians, patients, surgeons, institutions and medical associations do not always have the same needs. Starting from a review of the literature on centralization in hepatobiliary surgery, we will propose some guidelines that, while not data-driven due to low evidence in the literature, will be based on good clinical practice.

Multidisciplinary treatment for colorectal liver metastases in elderly patients

BACKGROUND

Limited data describe the therapeutic practice and outcomes of colorectal liver metastases (CRLMs) in elderly patients. We aimed to evaluate the impact of age on multidisciplinary treatment for CRLMs.

METHODS

We reviewed treatment and outcomes for patients in different age groups who underwent initial hepatectomy for CRLMs from 2004 through 2012.

RESULTS

We studied 462 patients who were divided into three groups by age: ≤ 64 years (n = 265), 65-74 years (n = 151), and ≥ 75 years (n = 46). The rate of major hepatectomy and incidence of postoperative complications did not differ between groups. Adjuvant chemotherapy was used less in the ≥ 75-year group (19.6%) than that in the ≤ 64 (54.3%) or 65-74 age group (43.5%). Repeat hepatectomy for liver recurrence was performed less in the ≥ 75-year group (35%) than in the ≤ 64 (57%) or 65-74 (66%) age group. The 5-year disease-specific survival (DSS) rate of 44.2% in the ≥ 75-year group was lower than in the ≤ 64 (59.0%) or 65-74 (64.7%) age group. Multivariate analysis revealed age ≥ 75 years was an independent predictor of poor DSS.

CONCLUSIONS

Liver resection for CRLMs can be performed safely in elderly patients. However, repeat resection for recurrence are performed less frequently in the elderly, which may lead to the poorer disease-specific prognosis.

Mortality and morbidity after hepatic resection in patients undergoing hemodialysis: analysis of a national inpatient database in Japan

BACKGROUND

Whether patients undergoing hemodialysis have greater risks of mortality and morbidity after hepatic resection remains unclear.

METHODS

We used the Diagnosis Procedure Combination database, a national inpatient database in Japan, to identify patients who underwent hepatic resection from July 2010 to March 2014. Propensity scorematching analysis was performed to compare morbidity and mortality between patients with and without hemodialysis.

RESULTS

Of 53,651 eligible patients, 498 (0.93%) underwent hemodialysis. Propensity score-matching analysis indicated greater in-hospital mortality in patients with than without hemodialysis (8.6% vs 2.0%; P < .001). Patients undergoing hemodialysis had more postoperative major complications than did patients not undergoing hemodialysis (18.1% vs 7.4%; P < .001). In the subgroup analyses for in-hospital mortality, the odds ratio of hemodialysis was 2.36 (95% confidence interval, 0.78-6.59; P = .067) in limited resection, 4.61 (95% confidence interval, 1.90-11.2; P < .001) in segmentectomy or sectoriectomy, and 5.58 (95% confidence interval, 3.40-14.9; P < .001) in bisectoriectomy or trisectoriectomy. In the age subgroup analyses, the odds ratio of hemodialysis was 4.38 (95% confidence interval, 2.66-7.21; P < .001) in patients aged <80 years and 7.20 (95% confidence interval, 1.55-36.7; P = .0011) in those aged ≥80 years.

CONCLUSION

Patients undergoing hemodialysis had a substantially increased risk of mortality and morbidity after hepatic resection. Surgical indications for major hepatectomy in patients undergoing hemodialysis who are ≥80 years of age may be limited and require careful scrutiny.

Are Older Adults With Hip Fractures Disadvantaged in Level 1 Trauma Centers?

BACKGROUND

Large regional hospitals achieve good outcomes for patients with complex conditions. However, recent studies have suggested that some patient groups might not benefit from treatment in higher-level trauma centers.

OBJECTIVE

To test the hypothesis that older adults with isolated hip fractures experience delayed surgical treatment and worse clinical outcomes when treated in higher-level trauma centers.

RESEARCH DESIGN

Retrospective cohort study using a statewide longitudinal database that captured 98% of inpatients within California (2007-2011).

SUBJECTS

All older adults (aged 65 y and above) admitted with an isolated hip fracture who did not require interhospital transfer.

MEASURES

Days to operation, length of stay, inhospital mortality, 30-day risk of unplanned readmission, 30-day venous thromboembolism, decubitus ulcers, and pneumonia.

RESULTS

There were 91,401 patients, 6.1% of whom were treated in a level 1 trauma center (L1TC), 17.7% in a level 2 trauma center (L2TC), and 70.2% in a nontrauma center (NTC). Within multivariable logistic and generalized linear regression models, patients treated in L1TCs underwent surgery later (predicted mean difference: 0.30 d; 95% CI, 0.08-0.53), had prolonged inpatient stays (0.99 d, 0.40-1.59), and had higher odds of both 30-day readmission (aOR=1.62; 95% CI, 1.35-1.93) and venous thromboembolism (aOR=1.32, 1.01-1.74) relative to NTCs. There were no differences in mortality, decubitus ulcers, or pneumonias. L2TCs were not different from NTCs across any of the measured outcomes.

CONCLUSIONS

Older adults with hip fractures may be disadvantaged in L1TCs. Further research should aim to develop our understanding of this disparity to ensure that all patient groups benefit from the resources and expertise available within these hospitals.

Primary Malignancy is an Independent Determinant of Morbidity and Mortality after Liver Resection

Although outcomes after liver resection have improved, there remains considerable perioperative morbidity and mortality with these procedures. Studies suggest a primary liver cancer diagnosis is associated with poorer outcomes, but the extent to which this is attributable to a higher degree of hepatic dysfunction is unclear. To better delineate this, we performed a matched pair analysis of primary versus metastatic malignancies using a national database. The American College of Surgeons National Surgical Quality Improvement Program (2005–2013) was analyzed to select elective liver resections. Diagnoses were sorted as follows: 1) primary liver cancers and 2) metastatic neoplasms. A literature review identified factors known to impact hepatectomy outcomes; these variables were evaluated by a univariate analysis. The most predictive factors were used to create similar groups from each diagnosis category via propensity matching. Multivariate regression was used to validate results in the wider study population. Outcomes were compared using chi-squared test and Fisher exact test. Matched groups of 4838 patients were similar by all variables, including indicators of liver function. A number of major complications were significantly more prevalent with a primary diagnosis; overall major morbidity rates in the metastatic and primary groups were 29.3 versus 41.6 per cent, respectively. The mortality rate for primary neoplasms was 4.6 per cent (vs 1.6%); this represents a risk of death nearly three-times greater (95% confidence interval = 2.20–3.81, P < 0.0001) in cancers of hepatic origin. Hepatectomy carries substantially higher perioperative risk when performed for primary liver cancers, independent of hepatic function and resection extent. This knowledge will help to improve treatment planning, patient education, and resource allocation in oncologic liver resection.

The Impact of Hospital/Surgeon Volume on Acute Renal Failure and Mortality in Liver Transplantation: A Nationwide Cohort Study

The aim of this study was to assess whether the case volume of surgeons and hospitals affects the rates of postoperative complications and survival after liver transplantation. This population-based retrospective cohort study included 2938 recipients of liver transplantation performed between 1998 and 2012, enrolled from the Taiwan National Health Insurance Research Database. They were divided into two groups, according to the cumulative case volume of their operating surgeons and the case volume of their hospitals. The duration of intensive care unit stay and post-transplantation hospitalization, postoperative complications, and mortality were analyzed. The results showed that, in the low and high case volume surgeons groups, respectively, acute renal failure occurred at the rate of 14.11% and 5.86% (p<0.0001), and the overall mortality rates were 19.61% and 12.44% (p<0.0001). In the low and high case volume hospital groups, respectively, acute renal failure occurred in 11% and 7.11% of the recipients (p = 0.0004), and the overall mortality was 18.44% and 12.86% (p<0.0001). These findings suggest that liver transplantation recipients operated on higher case volume surgeons or in higher case volume hospitals have a lower rate of acute renal failure and mortality.

The utility of the MELD score in predicting mortality following liver resection for metastasis

BACKGROUND

The MELD score has been demonstrated to be predictive of hepatectomy outcomes in mixed patient samples of primary and secondary liver cancers. Because MELD is a measure of hepatic dysfunction, prior conclusions may rely on the high prevalence of cirrhosis observed with primary lesions. This study aims to evaluate MELD score as a predictor of mortality and develop a risk prediction model for patients specifically undergoing hepatic metastasectomy.

METHODS

ACS-NSQIP 2005-2013 was analyzed to select patients who had undergone liver resections for metastases. A receiver operating characteristic (ROC) analysis determined the MELD score most associated with 30-day mortality. A literature review identified variables that impact hepatectomy outcomes. Significant factors were included in a multivariable analysis (MVA). A risk calculator was derived from the final multivariable model.

RESULTS

Among the 14,919 patients assessed, the mortality rate was 2.7%, and the median MELD was 7.3 (range = 34.4). A MELD of 7.24 was identified by ROC (sensitivity = 81%, specificity = 51%, c-statistic = 0.71). Of all patients above this threshold, 4.4% died at 30 days vs. 1.1% in the group ≤7.24. This faction represented 50.1% of the population but accounted for 80.3% of all deaths (p < 0.001). The MVA revealed mortality to be increased 2.6-times (OR = 2.55, 95%CI 1.69-3.84, p < 0.001). A risk calculator was successfully developed and validated.

CONCLUSIONS

MELD>7.24 is an important predictor of death following hepatectomy for metastasis and may prompt a detailed assessment with the provided risk calculator. Attention to MELD in the preoperative setting will improve treatment planning and patient education prior to oncologic liver resection.

Beyond volume: hospital-based healthcare technology as a predictor of mortality for cardiovascular patients in Korea

To examine whether hospital-based healthcare technology is related to 30-day postoperative mortality rates after adjusting for hospital volume of cardiovascular surgical procedures.This study used the National Health Insurance Service-Cohort Sample Database from 2002 to 2013, which was released by the Korean National Health Insurance Service. A total of 11,109 cardiovascular surgical procedure patients were analyzed. The primary analysis was based on logistic regression models to examine our hypothesis.After adjusting for hospital volume of cardiovascular surgical procedures as well as for all other confounders, the odds ratio (OR) of 30-day mortality in low healthcare technology hospitals was 1.567-times higher (95% confidence interval [CI] = 1.069-2.297) than in those with high healthcare technology. We also found that, overall, cardiovascular surgical patients treated in low healthcare technology hospitals, regardless of the extent of cardiovascular surgical procedures, had the highest 30-day mortality rate.Although the results of our study provide scientific evidence for a hospital volume-mortality relationship in cardiovascular surgical patients, the independent effect of hospital-based healthcare technology is strong, resulting in a lower mortality rate. As hospital characteristics such as clinical pathways and protocols are likely to also play an important role in mortality, further research is required to explore their respective contributions.

Validation of the board certification system for expert surgeons (hepato-biliary-pancreatic field) using the data of the National Clinical Database of Japan: part 1 - Hepatectomy of more than one segment

BACKGROUND

The objective of this study was to validate the board certification system of the Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHBPS) using the data of hepatectomy cases from the National Clinical Database (NCD) of Japan.

METHODS

Minimal required annual numbers of high-level hepato-biliary-pancreatic (HBP) surgeries were 50 for a board-certified A training institution and 30 for a board-certified B training institution. Records of 14,970 patients who had undergone hepatectomy of more than one segment (MOS), excluding lateral segmentectomy, during 2011 and 2012 were analyzed according to the category of board-certified institution and with or without participation of board-certified instructors or expert surgeons.

RESULTS

Thirty-day mortality and operative mortality of 14,970 patients after MOS hepatectomy were 1.9% and 3.8%, respectively. Operative mortality rates after MOS hepatectomies performed at certified A institutions, certified B institutions, and non-certified institutions were 3.1%, 3.8%, and 4.5%, respectively (P < 0.001). The operative mortality rates after MOS hepatectomies performed with participation of certified instructors or expert surgeons were better than those without (3.5% vs. 4.3%, P = 0.012). A multiple logistic regression model showed that the cutoffs of high-level HBP surgeries performed per year at hospitals that predicted operative mortality after MOS hepatectomies were 10 and 50.

CONCLUSIONS

Competences and requirements for board-certified institutions, instructors, and expert surgeons to perform hepatectomy were found to be appropriate.

Factors Associated With Small Bowel Obstruction Following Appendectomy: A Population-Based Study

Postoperative small bowel obstruction (SBO) is a common complication of appendectomy. This study aimed to assess risk factors for SBO following appendectomy.This retrospective cohort study used the 2006 to 2008 Taiwan National Health Insurance Research Database. We evaluated adult patients with acute appendicitis who underwent open (OA) or laparoscopic appendectomy (LA) between January 1, 2006 and December 31, 2008. Excluded were patients with a history of abdominal surgery and SBO before the index operation, or abdominal surgery between the appendectomy and initial diagnosis of bowel obstruction as an identifiable cause of SBO. Factors thought to influence postoperative SBO were highlighted. The OA and LA cohorts were matched by propensity score, and the hazard ratios (HRs) and 95% confidence interval (CIs) of SBO were calculated.We enrolled 11,289 patients who underwent OA, and 11,289 matched controls who underwent LA. OA patients had significant risk of adhesive SBO compared with the LA group (adjusted HR: 1.7, 95% CI: 1.11-2.63). Further analysis revealed that that female sex (adjusted HR: 1.79, 95% CI: 1.17-2.72), CCI score of 1 or ≥2 (adjusted HR: 3.16, 95% CI: 1.76-5.67; adjusted HR: 4.03, 95% CI: 1.57-10.34), complicated appendicitis (adjusted HR: 1.68, 95% CI: 1.05-2.69), treatment in district hospitals increased risk of adhesive SBO.Female sex, complicated appendicitis, more comorbidities, and treatment in district hospitals are factors associated with a risk of SBO after appendectomy. Our findings confirmed that a laparoscopic approach is better than an open approach.

Hospital case volume and outcomes for proximal femoral fractures in the USA: an observational study

OBJECTIVE

To explore whether older adults with isolated hip fractures benefit from treatment in high-volume hospitals.

DESIGN

Population-based observational study.

SETTING

All acute hospitals in California, USA.

PARTICIPANTS

All individuals aged ≥65 that underwent an operation for an isolated hip fracture in California between 2007 and 2011. Patients transferred between hospitals were excluded.

PRIMARY AND SECONDARY OUTCOMES

Quality indicators (time to surgery) and patient outcomes (length of stay, in-hospital mortality, unplanned 30-day readmission, and selected complications).

RESULTS

91,401 individuals satisfied the inclusion criteria. Time to operation and length of stay were significantly prolonged in low-volume hospitals, by 1.96 (95% CI 1.20 to 2.73) and 0.70 (0.38 to 1.03) days, respectively. However, there were no differences in clinical outcomes, including in-hospital mortality, 30-day re-admission, and rates of pneumonia, pressure ulcers, and venous thromboembolism.

CONCLUSIONS

These data suggest that there is no patient safety imperative to limit hip fracture care to high-volume hospitals.