Thirty-Day Morbidity after Simultaneous Resection of Colorectal Cancer and Colorectal Liver Metastasis: American College of Surgeons NSQIP Analysis.

BACKGROUND: Approximately 20% of patients with colorectal cancer (CRC) present with synchronous liver metastases (CRLM). The decision to resect simultaneously or sequentially remains controversial. The primary aim of this study was to determine whether simultaneous resection of CRC and CRLM is associated with increased complications compared to isolated resection. STUDY DESIGN: Prospective data from the American College of Surgeons (ACS) NSQIP, including the ACS NSQIP procedure-specific colectomy and hepatectomy modules from 2014 to 2017, were reviewed in a retrospective cohort study. Primary study outcome was combined 30-day complication rates; secondary outcomes included colectomy and hepatectomy-specific complication. Multivariable logistic regression was performed to control for confounding factors associated with postoperative complication. RESULTS: A total of 23,643 patients underwent colectomy, 7,462 hepatectomy, and 592 simultaneous resection for CRC and CLRM. Overall morbidity was higher among patients treated with simultaneous resection (29.9%) compared with either isolated colorectal (22.2%) or hepatic resection (17.1%; p < 0.001). Additionally, postoperative ileus (36.4% vs 19.1%) and anastomotic failure (7.9% vs 3.8%) were more common after simultaneous resection compared with colorectal resection (p < 0.05). Similarly, rates of bile leak (8.3% vs 6.2%, p = 0.195) and post-hepatectomy liver failure (8.7% vs 3.8%, p < 0.001) were higher after simultaneous resection compared with isolated hepatectomy. By multivariable logistic regression, simultaneous resection was associated with increased overall complication compared with isolated colon (odds ratio 1.64 [95% CI 1.36 to 1.96]) or liver resection (odds ratio 2.11 [95% CI 1.75 to 2.55]), as well as increased procedure-specific complication. CONCLUSIONS: Although simultaneous resection offers definitive resection for patients with synchronous CRC and CRLM, it is associated with significantly increased 30-day overall and procedure-specific postoperative morbidity.

Clopidogrel use as a risk factor for poor outcomes after kidney transplantation.

BACKGROUND: Limited data are available on outcome implications of clopidogrel use before kidney transplantation. METHODS: A novel dataset linking national transplant registry data with records from a large pharmacy claims clearinghouse (2005 to 2010) was examined to estimate risks of post-transplant death and graft failure associated with clopidogrel fills within 90 or more than 90 days before transplant. RESULTS: Clopidogrel fills within 90 days of transplant were associated with 61% of increased relative mortality risk and 23% of increased graft failure risk. Risks were higher in those whose last clopidogrel fill was more than 90 days before transplantation (111% for death, 59% for graft loss). Adverse prognostic associations persisted among recipients of live and deceased donor allografts, older recipients, and those with diabetes or reported cardiovascular disease. CONCLUSIONS: Clopidogrel use before kidney transplantation portends increased risks of post-transplant death and graft loss. Pharmacy claims may identify novel prognostic markers not currently captured in the transplant registry.

Prognostic impact of mechanical ventilation after liver transplantation: a national database study.

BACKGROUND: The impact of mechanical ventilatory support (MCVS) on mortality and graft loss after liver transplantation (LT) is not well described. METHODS: Multivariate analysis of a novel database linking national transplant registry and Medicare claims data was used to assess the impact of early MCVS on mortality and graft survival following LTs performed between 2002 and 2008. RESULTS: Among 10,517 LT recipients, 6.9% (n = 726) required postoperative MCVS, 25.6% of whom required less than 96 hours, 24.2% required 96 hours or longer, and 50.1% received an unspecified duration. Significant predictors of prolonged MCVS included older age, female sex, pretransplant dialysis requirement, and ascites. After multivariate adjustment, MCVS of 96 hours or longer was associated with nearly 3 times the adjusted hazard ratio of mortality (2.95, P < .001), while MCVS less than 96 hours was not significantly associated with mortality (adjusted hazard ratio .88, P = .55). CONCLUSIONS: Recognition of LT patients at risk for prolonged MCVS may help to reduce the incidence and consequences of this complication.

Accountability for end-stage organ care: implications of geographic variation in access to kidney transplantation.

BACKGROUND: The provision of effective surgical care for end-stage renal disease (ESRD) requires efficient evaluation and transplantation. Prior assessments of transplant access have focused primarily on waitlisted patients rather than the overall populations served by "accountable" providers of transplant services. METHODS: Novel transplant referral regions (TRRs) were defined using United Network for Organ Sharing registry data for 301,092 kidney transplant listings to assign zip codes to "accountable" transplant programs. Subsequently, risk-adjusted observed to expected (O:E) rates of listing and transplant procedures were calculated for each TRR. Finally, the impact of variation in TRR listing and transplant rates on mortality was assessed for ESRD patients <60 years old diagnosed between 2000 and 2008. RESULTS: In total, 113 TRRs were defined, 51% of which included >1 transplant center. The likelihood of being evaluated and listed for transplant varied significantly between TRRs (risk-adjusted O:E, 0.58-1.95). Variation was greater for the overall transplant rate (0.62-2.19), living donor transplantation (0.36-3.08), and donation after cardiac death transplant (0-15.4) than for standard criteria donors (0.64-2.86). Mortality was decreased for ESRD patients living in TRRs in the highest tertile of listings (hazard ratio, 0.89; P < .0001) and transplantation (0.90; P < .0001). CONCLUSION: Residence in a TRR with care delivery systems that increase access to transplant services is associated with significant, risk-adjusted decreases in ESRD-related mortality. Transplant centers should continue to focus on improving access to care within the communities they serve.

National assessment of early biliary complications following liver transplantation: incidence and outcomes.

Despite improved overall liver transplant outcomes, biliary complications remain a significant cause of morbidity. A national data set linking transplant registry and Medicare claims data for 17,012 liver transplant recipients was used to identify all recipients with a posttransplant biliary diagnosis code within the first 6 months after transplantation. Patients were further categorized as follows: a diagnosis without a procedure, a diagnosis and an associated radiological or endoscopic procedure, or a diagnosis treated with surgery. Overall, 15.0% had a biliary diagnosis, 11.2% required a procedure, and 2.2% had a surgical revision. Factors independently associated with biliary complications included donation after cardiac death (DCD), donor age, recipient age, split grafts, and long cold ischemia times. Graft loss was significantly more common for patients with biliary diagnoses [adjusted hazard ratio (aHR) = 1.89, confidence interval (CI) = 1.63-2.19], interventions (aHR = 2.08, CI = 1.77-2.44), and surgical procedures (aHR = 1.80, CI = 1.31-2.49). Mortality after transplantation was also markedly increased for patients with biliary diagnoses (aHR = 2.18, CI = 1.97-2.40), procedures (aHR = 2.21, CI = 1.99-2.46), and surgeries (aHR = 1.77, CI = 1.41-2.23). In stratified analyses, the impact of early biliary complications was greater for DCD liver recipients, but they remained highly significant for recipients of allografts from brain-dead donors as well. Reducing biliary complications should improve posttransplant survival and reduce graft loss.

Consistency of racial variation in medical outcomes among publicly and privately insured living kidney donors.

BACKGROUND: Racial disparities in health outcomes after living donation have been reported, but generalizability is not known. METHODS: We linked Organ Procurement and Transplantation Network (OPTN) registry data for 4,007 living kidney donors in 1987 to 2008 with Medicare billing claims (2000-2008). Cox regression with left and right censoring was used to estimate the frequencies and relative risks of postdonation medical diagnoses according to race. Patterns were compared with findings from a previous linkage of OPTN donor records and private insurance claims. RESULTS: Among the Medicare-insured donors, 8% were African American and 5.7% were Hispanic. Diagnosis frequencies at 5 years after donation in the Medicare- versus privately insured donors included the following: malignant hypertension, 5.0% versus 0.9%; diabetes, 18.5% versus 4.1%; and chronic kidney disease, 21.8% versus 4.9%. After age and sex adjustment in the Medicare sample, African Americans, as compared with white donors, experienced higher risks of any hypertension diagnosis, including 2.4 times the likelihood of malignant hypertension (adjusted hazard ratio [aHR], 2.35; 95% confidence interval [CI], 1.40-3.93), and more common diabetes (aHR, 1.50; 95% CI, 1.12-2.04), chronic kidney disease (aHR, 1.84; 95% CI, 1.37-2.47), and proteinuria (aHR, 2.44; 95% CI, 1.45-4.11) diagnoses. Relative patterns for privately insured African American versus white donors were similar, including approximately three times the risk of malignant hypertension (aHR, 3.27; 95% CI, 1.82-5.88) and twice the relative risks of chronic kidney disease and proteinuria. CONCLUSIONS: Consistent demonstration of racial variation in postdonation medical conditions regardless of sample/payer source supports the need for continued study of mediators and consequences of outcomes in non-white donors.

Clinical correlates, outcomes and healthcare costs associated with early mechanical ventilation after kidney transplantation.

BACKGROUND: Information is lacking on the frequency, clinical implications, and costs of respiratory failure requiring mechanical ventilation after kidney transplantation. METHODS: U.S. Renal Data System records for Medicare-insured kidney transplant recipients (1995 to 2007; n = 88,392) were examined to identify post-transplantation mechanical ventilation from billing claims within 30 days after transplantation. RESULTS: Post-transplantation mechanical ventilation was required among 2.1% of the cohort. Independent correlates of early mechanical ventilation included recipient age, low body mass index, coronary artery disease, and cerebrovascular disease. Post-transplantation mechanical ventilation was twice as likely with delayed graft function (adjusted odds ratio, 2.13; P < .001) and 35% lower among recipients of living versus deceased donor allografts. Patients needing early mechanical ventilation experienced 5-fold higher 1-year mortality, as well as significantly higher Medicare costs during the transplant hospitalization and first post-transplantation year. CONCLUSIONS: Recognition of patients at risk for post-transplantation respiratory failure may help direct protocols for reducing the incidence and consequences of this complication.

Transplant certification and quality assessment: time to take the front line?

In the beginning of the past decade, a series of highly publicized events led the general public to question the ability of the transplant community to effectively police itself. Common to the events was the perception that insufficient regulation of the transplant community allowed both unintentional errors and, rarely, purposeful violations of policy, to affect the safety and justice of organ allocation and transplant practice. The goal of this article is to discuss the resulting regulatory responses to these events and to highlight one transplant center's experience with the current external review process. The potential benefits of using process control charts to prospectively monitoring a center's outcomes, as well as the benefits of implementing procedures that ensure the quality of publically reported data, are described. Specifically, the critical need for each center to understand the components, limitations, and implications of public outcome reporting and to define processes that promote real time self-evaluation and quality improvement are demonstrated.

Obesity and kidney transplant candidates: how big is too big for transplantation?.

Obesity impacts many inter-related, and sometimes conflicting, considerations for transplant practice. In this article, we describe an approach for applying available data on the importance of body composition to the kidney transplant population that separates implications for candidate selection, risk stratification among selected candidates, and interventions to optimize health of the individual. Transplant recipients with obesity defined by elevated body mass index (BMI) have been shown in many (but not all) studies to experience an array of adverse outcomes more commonly than normal-weight transplant recipients, including wound infections, delayed graft function, graft failure, cardiac disease, and increased costs. However, current studies have not defined limits of body composition that preclude clinical benefit from transplantation compared with long-term dialysis in patients who have passed a transplant evaluation. Formal cost-effectiveness studies are needed to determine if payers and society should be compensating centers for clinical and financial risks of transplanting obese end-stage renal disease patients. Recent studies also demonstrate the limitations of BMI alone as a measure of adiposity, and further research should be pursued to define practical measures of body composition that refine accuracy for outcomes prediction. Regarding individual management, observational registry studies have not found beneficial associations of pretransplant weight loss with patient or graft survival. However, association studies cannot distinguish purposeful from unintentional weight loss as a result of illness and comorbidity. Prospective evaluations of the impact of targeted risk modification efforts in this population including dietary changes, monitored exercise programs, and bariatric surgery are urgently needed.

Disparities in liver transplantation before and after introduction of the MELD score.

CONTEXT: In February 2002, the allocation system for liver transplantation became based on the Model for End-Stage Liver Disease (MELD) score. Before MELD, black patients were more likely to die or become too sick to undergo liver transplantation compared with white patients. Little information exists regarding sex and access to liver transplantation. OBJECTIVE: To determine the association between race, sex, and liver transplantation following introduction of the MELD system. DESIGN, SETTING, AND PATIENTS: A retrospective cohort of black and white patients (> or = 18 years) registered on the United Network for Organ Sharing liver transplantation waiting list between January 1, 1996, and December 31, 2000 (pre-MELD cohort, n = 21 895) and between February 28, 2002, and March 31, 2006 (post-MELD cohort, n = 23 793). MAIN OUTCOME MEASURES: Association between race, sex, and receipt of a liver transplant. Separate multivariable analyses evaluated cohorts within each period to identify predictors of time to death and the odds of dying or receiving liver transplantation within 3 years of listing. Patients with hepatocellular carcinoma were analyzed separately. RESULTS: Black patients were younger (mean [SD], 49.2 [10.7] vs 52.4 [9.2] years; P < .001) and sicker (MELD score at listing: median [interquartile range], 16 [12-22] vs 14 [11-19]; P < .001) than white patients on the waiting list for both periods. In the pre-MELD cohort, black patients were more likely to die or become too sick for liver transplantation than white patients (27.0% vs 21.7%) within 3 years of registering on the waiting list (odds ratio [OR], 1.51; 95% confidence interval (CI), 1.15-1.98; P = .003). In the post-MELD cohort, black race was no longer associated with increased likelihood of death or becoming too sick for liver transplantation (26.5% vs 22.0%, respectively; OR, 0.96; 95% CI, 0.74-1.26; P = .76). Black patients were also less likely to receive a liver transplant than white patients within 3 years of registering on the waiting list pre-MELD (61.6% vs 66.9%; OR, 0.75; 95% CI, 0.59-0.97; P = .03), whereas post-MELD, race was no longer significantly associated with receipt of a liver transplant (47.5% vs 45.5%, respectively; OR, 1.04; 95% CI, 0.84-1.28; P = .75). Women were more likely than men to die or become too sick for liver transplantation post-MELD (23.7% vs 21.4%; OR, 1.30; 95% CI, 1.08-1.47; P = .003) vs pre-MELD (22.4% vs 21.9%; OR, 1.08; 95% CI, 0.91-1.26; P = .37). Similarly, women were less likely than men to receive a liver transplant within 3 years both pre-MELD (64.8% vs 67.6%; OR, 0.80; 95% CI, 0.70-0.92; P = .002) and post-MELD (39.9% vs 48.7%; OR, 0.70; 95% CI, 0.62-0.79; P < .001). CONCLUSION: Following introduction of the MELD score to the liver transplantation allocation system, race was no longer associated with receipt of a liver transplant or death on the waiting list, but disparities based on sex remain.

Relationship between provider volume and outcomes for orthotopic liver transplantation.

INTRODUCTION: Recent data suggests that the previously demonstrable relationship between hospital volume and outcomes for liver transplant procedures may no longer exist. Furthermore, to our knowledge, no study has been published examining whether individual surgeon volume is associated with outcomes in liver transplantation. MATERIALS AND METHODS: The Nationwide Inpatient Sample database was used to obtain early clinical outcome and resource utilization data for liver transplant procedures performed in the USA from 1988 through 2003. The relationship between surgeon and hospital volume and early clinical outcomes was analyzed with and without adjustment for certain confounding variables such as patient age and presence of co-morbid disease. RESULTS: The in-hospital mortality rate, major postoperative complication rate, and length of hospital stay after liver transplantation did not differ significantly based on hospital procedural volume. These outcome variables did, however, exhibit a statistically significant inverse relationship with individual surgeon volume of liver transplant procedures. A significant relationship between procedure volume and outcomes for liver transplantation cannot be demonstrated at the level of transplant center, but does appear to exist at the level of the individual transplant center. CONCLUSION: Minimal volume requirements for individual liver transplant surgeons may be justified, pending validation of this volume-outcomes relationship using a clinical data source.

Frequency and predictors of de novo hepatocellular carcinoma in patients awaiting orthotopic liver transplantation during the model for end-stage liver disease era.

In the current system of allocation, patients awaiting orthotopic liver transplantation (OLT) remain at risk of developing de novo hepatocellular carcinoma (HCC) and removal from the waiting list. Using the United Network for Organ Sharing database, we calculated the rate and identified predictors of de novo HCC in patients listed for OLT between February 2002 and December 2004. Among 8566 patients, 1167 (13.6%) developed de novo HCC. Predictors of increased odds of de novo HCC were older age, male gender, Asian race, other race, hepatitis C, and hepatitis B. A sensitivity analysis of 2067 patients waiting at least 6 months found that 16.2% developed de novo HCC. Older age [odds ratio (OR) 1.05; 95% confidence interval (CI) 1.03, 1.07], male gender (OR 2.01; 95% CI 1.49, 2.71), Asian race (OR 2.39; 95% CI 1.20, 4.76), other race (OR 1.94; 95% CI 1.40, 2.68), hepatitis C (OR 2.36; 95% CI 1.76, 3.16), and hepatitis B (OR 1.96; 95% CI 1.19, 3.23) remained predictors of increased odds of de novo HCC, and alcoholic liver disease (OR 1.40; 95% CI 1.06, 1.86) emerged as a predictor of increased odds of de novo HCC. A significant proportion of patients listed for OLT develop de novo HCC. Identifying predictors of HCC in these patients may facilitate timely HCC screening and diagnosis.

Temporal trends in early clinical outcomes and health care resource utilization for liver transplantation in the United States.

INTRODUCTION: Procedures such as liver transplantation, which entail large costs while benefiting only a small percentage of the population, are being increasingly scrutinized by third-party payors. The purpose of our study was to conduct a longitudinal analysis of the early clinical outcomes and health care resource utilization for liver transplantation in the United States. METHODS: The Nationwide Inpatient Sample database was used to conduct a longitudinal analysis of the clinical outcome and resource utilization data for liver transplantation procedures in adult recipients performed in the United States over three time periods (Period I: 1988-1993; Period II: 1994-1998: Period III: 1999-2003). RESULTS: Compared to Period I, adult liver transplant recipients were more likely to be male, older, and non-White in Period III. Recipients were more likely to have at least one major comorbidity preoperatively than in Period I. The in-hospital mortality rate after liver transplantation decreased significantly from Period I to Period III, but the major intraoperative and postoperative complication rates increased over the same time period. Mean length of hospital stay decreased over the 15-year period, but the percentage of patients with a non-routine discharge status increased. CONCLUSION: Our findings indicate that the rate of postoperative complications and non-routine discharges after liver transplantation is increasing. However, these negative changes in the cost-outcomes relationship for liver transplantation are balanced by improving postoperative survival rates and reductions in the length of hospital stay.

The current status of living donor liver transplantation.

In response to the critical organ shortage, transplant professionals have utilized living donors in an attempt to decrease the mortality rate associated with waiting on the liver transplant list. Although the surgical techniques were first utilized clinically 15 years ago, application of LDLT has been somewhat limited by the steep learning curve associated with developing a program. Clinical success with LDLT in children was realized early in the experience and application of the techniques to the adult population has occurred more recently. Although transplant centers embark on LDLT with enthusiasm, the safety of the donor must always be at the forefront of the process. Potential donors must come to the decision to donate without pressure from members of the family or transplant team. He/she should also be assigned advocates who constantly promote the donor's best interest. Failure to adhere to strict donor evaluation protocols and standardized operative techniques could result in disastrous consequences.

Acute kidney transplant failure following transurethral bladder polyp fulguration.

Ureteral obstruction and anastomotic leak represent the most common urologic complications of kidney transplantation. Delay in diagnosis or treatment can lead to allograft loss. Obstruction of the ureter occurs in 2% of kidney transplant recipients. Although the majority of cases are immediate technical complications of the operation, subsequent manipulation of the genitourinary system can result in iatrogenic ureteral injury. We report the case of a long-term kidney transplant recipient who developed obstructive uropathy and acute renal failure requiring dialysis after undergoing cystoscopy and bladder polyp fulguration. The etiology was inadvertent thermal injury of the ureteroneocystostomy incurred during the procedure. After attempted percutaneous management, definitive open repair resulted in a return of allograft function to baseline.

Prognostic significance of microvascular thrombosis in donor kidney allograft biopsies.

BACKGROUND: With a continuing demand for donor kidneys for organ transplantation, it is important to understand the significance of pathologic findings in the donor organ before transplantation. Microvascular thrombosis is sometimes encountered in association with disseminated intravascular coagulation in the donor, and it is unclear whether this finding may affect immediate allograft function and long-term graft survival. To further elucidate this question, we examined our experience with microvascular thrombosis in donor biopsies in the kidney transplant program at our institution. METHODS: Donor kidney biopsies showing microvascular thrombosis were identified from consecutive donor biopsies in the Duke University Medical Center transplant file database between January 1, 1995 and December 31, 2000. These biopsies and all other kidney biopsies and specimens from the recipients of these kidneys thus identified were reviewed. Sections were stained using a variety of methods, including hematoxylin-eosin, periodic acid-Schiff, methenamine silver, and Masson trichrome methods. Clinical records of the transplant recipients of these kidneys were also reviewed to assess allograft performance and survival. RESULTS: From 230 consecutive donor kidney biopsies, we identified eight cases exhibiting donor-microvascular thrombosis. Mean follow-up times were 27.5 months for the thrombi group and 35 months for the non-thrombi group. Recipients of grafts with donor thrombi were more likely to exhibit delayed graft function, but graft function at 1 and 2 years and graft survival were similar between the two groups. Subsequent posttransplantation biopsies in five of eight cases showed no evidence of residual thrombosis. CONCLUSIONS: These data suggest that the presence of donor microvascular thrombosis does not portend poor outcome in renal transplantation.