Developing deep learning-based strategies to predict the risk of hepatocellular carcinoma among patients with nonalcoholic fatty liver disease from electronic health records.

OBJECTIVE: The accuracy of deep learning models for many disease prediction problems is affected by time-varying covariates, rare incidence, covariate imbalance and delayed diagnosis when using structured electronic health records data. The situation is further exasperated when predicting the risk of one disease on condition of another disease, such as the hepatocellular carcinoma risk among patients with nonalcoholic fatty liver disease due to slow, chronic progression, the scarce of data with both disease conditions and the sex bias of the diseases. The goal of this study is to investigate the extent to which the aforementioned issues influence deep learning performance, and then devised strategies to tackle these challenges. These strategies were applied to improve hepatocellular carcinoma risk prediction among patients with nonalcoholic fatty liver disease. METHODS: We evaluated two representative deep learning models in the task of predicting the occurrence of hepatocellular carcinoma in a cohort of patients with nonalcoholic fatty liver disease (n = 220,838) from a national EHR database. The disease prediction task was carefully formulated as a classification problem while taking censorship and the length of follow-up into consideration. RESULTS: We developed a novel backward masking scheme to deal with the issue of delayed diagnosis which is very common in EHR data analysis and evaluate how the length of longitudinal information after the index date affects disease prediction. We observed that modeling time-varying covariates improved the performance of the algorithms and transfer learning mitigated reduced performance caused by the lack of data. In addition, covariate imbalance, such as sex bias in data impaired performance. Deep learning models trained on one sex and evaluated in the other sex showed reduced performance, indicating the importance of assessing covariate imbalance while preparing data for model training. CONCLUSIONS: The strategies developed in this work can significantly improve the performance of hepatocellular carcinoma risk prediction among patients with nonalcoholic fatty liver disease. Furthermore, our novel strategies can be generalized to apply to other disease risk predictions using structured electronic health records, especially for disease risks on condition of another disease.

A nationwide analysis of clinical trial participation for common hepato-pancreato-biliary malignancies demonstrates survival advantages for subsets of trial patients but disparities in and infrequency of enrollment.

BACKGROUND: We describe factors associated with trial enrollment for patients with hepato-pancreato-biliary (HPB) malignancies. We analyzed the association and effect of trial enrollment on overall survival (OS). METHODS: The National Cancer Database (2004-2017) was queried for common HPB malignancies (pancreatic adenocarcinoma [PDAC] & neuroendocrine tumors, hepatocellular carcinoma [HCC], biliary tract cancers [BTC]). Multivariable logistic regression was used to identify factors associated with trial enrollment. OS was analyzed by multivariable Cox regression. Inverse-probability-weighted Cox regression was utilized to determine the effect of trial enrollment on OS. RESULTS: A total of 1573 (0.3%) of 511,639 patients were enrolled in trials; pancreatic malignancy: 1214 (0.4%); HCC: 217 (0.14%); BTC: 106 (0.15%). HCC and BTC were associated with lower likelihood of enrollment compared with pancreatic malignancy. Black and Hispanic patients were less likely to be enrolled compared to White patients. Treatment at academic facilities and metastatic disease were associated with higher likelihood of enrollment. Enrollment was associated with higher OS for PDAC, metastatic HCC, and metastatic BTC. Trial enrollment exhibited an OS advantage for PDAC and metastatic HCC. CONCLUSION: Nationally, fewer than 1% of patients with HPB malignancies were enrolled in clinical trials. There are racial, sociodemographic, and facility-based disparities in trial enrollment.

Medicaid expansion is associated with a higher likelihood of early diagnosis, resection, transplantation, and overall survival in patients with hepatocellular carcinoma.

BACKGROUND: We examined the association between Medicaid expansion (ME) and the diagnosis, treatment, and survival of patients with hepatocellular carcinoma (HCC). METHODS: We identified patients with HCC <65yrs with Medicaid or without insurance within the National Cancer Database before (2010-2013) or after (2015-2017) ME with early (cT1) or intermediate/advanced (cT2-T4 or M1) disease. RESULTS: We identified 4848 patients with HCC before and 4526 after ME. Prior to ME, there was no association between future ME status and diagnosis of early HCC (34.5% vs. 32.9%). There was no association between future ME status and treating early HCC with ablation, resection, or transplantation. Patients with early HCC in future ME states were less likely to die (HR = 0.81, 95% CI: 0.67-0.98). After ME, patients in ME states were more likely to be diagnosed with early HCC (39.2% vs. 32.1%). Patients with early disease in ME states were more likely to undergo resection (OR=1.78, 95% CI: 1.16-2.75) or transplantation (OR=3.20, 95% CI: 1.40-7.33). There was a further associated decrease in the hazard of death (HR=0.68, 95% CI: 0.54-0.86). CONCLUSION: ME was associated with early diagnosis of HCC. For early HCC, ME was associated with increased utilization of resection and transplantation and improvement in survival.

Black race is independently associated with underutilization of transplantation for clinical T1 hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is a leading cause of cancer mortality. Operative management of early disease includes ablation, resection, and transplantation. We compared the operative management of early-stage HCC in patients stratified by race. METHODS: We identified patients with cT1 HCC and Charlson-Deyo score 0-1 in the National Cancer Database (2004-2016). We compared operative/non-operative management by race, adjusting for clinicodemographic variables. We performed marginal standardization of logistic regression to ascertain adjusted probabilities of resection or transplantation in patients under 70 years of age with insurance. RESULTS: A total of 25,029 patients were included (White = 20,410; Black = 4619). After adjusting for clinico demographic variables, Black race was associated with a lower likelihood of undergoing operative intervention (OR 0.89,p = 0.009). Black patients were more likely to undergo resection (OR 1.23,p < 0.001) and less likely to undergo transplantation (OR 0.60,p < 0.001). Marginal standardization models demonstrated Black race was associated with increased probability of resection in patients >50yrs, with private insurance/Medicare, and lower probability of transplantation regardless of age or insurance payor. CONCLUSION: Black race is associated with lower rates of hepatic transplantation and higher rates of hepatic resection for early HCC regardless of age or insurance payor. The etiology of these disparities is multifactorial and correcting the root causes represents a critical area for improvement.

A Novel Method to Improve Perfusion of Ex Vivo Pumped Human Kidneys.

OBJECTIVE: To determine if addition of the S-nitrosylating agent ethyl nitrite (ENO) to the preservation solution can improve perfusion parameters in pumped human kidneys. BACKGROUND: A significant percentage of actively stored kidneys experience elevations in resistance and decreases in flow rate during the ex vivo storage period. Preclinical work indicates that renal status after brain death is negatively impacted by inflammation and reduced perfusion-processes regulated by protein S-nitrosylation. To translate these findings, we added ENO to the preservation solution in an attempt to reverse the perfusion deficits observed in nontransplanted pumped human kidneys. METHODS: After obtaining positive proof-of-concept results with swine kidneys, we studied donated human kidneys undergoing hypothermic pulsatile perfusion deemed unsuitable for transplantation. Control kidneys continued to be pumped a 4°C (ie, standard of care). In the experimental group, the preservation solution was aerated with 50 ppm ENO in nitrogen. Flow rate and perfusion were recorded for 10 hours followed by biochemical analysis of the kidney tissue. RESULTS: In controls, perfusion was constant during the monitoring period (ie, flow rate remained low and resistance stayed high). In contrast, the addition of ENO produced significant and sustained reductions in resistance and increases in flow rate. ENO-treated kidneys had higher levels of cyclic guanosine monophosphate, potentially explaining the perfusion benefits, and increased levels of interleukin-10, suggestive of an anti-inflammatory effect. CONCLUSIONS: S-Nitrosylation therapy restored the microcirculation and thus improved overall organ perfusion. Inclusion of ENO in the renal preservation solution holds promise to increase the number and quality of kidneys available for transplant.

Predictors of Outcomes of COVID-19 in Patients With Chronic Liver Disease: US Multi-center Study.

BACKGROUND & AIMS: Chronic liver disease (CLD) represents a major global health burden. We undertook this study to identify the factors associated with adverse outcomes in patients with CLD who acquire the novel coronavirus-2019 (COVID-19). METHODS: We conducted a multi-center, observational cohort study across 21 institutions in the United States (US) of adult patients with CLD and laboratory-confirmed diagnosis of COVID-19 between March 1, 2020 and May 30, 2020. We performed survival analysis to identify independent predictors of all-cause mortality and COVID-19 related mortality, and multivariate logistic regression to determine the risk of severe COVID-19 in patients with CLD. RESULTS: Of the 978 patients in our cohort, 867 patients (mean age 56.9 ± 14.5 years, 55% male) met inclusion criteria. The overall all-cause mortality was 14.0% (n = 121), and 61.7% (n = 535) had severe COVID-19. Patients presenting with diarrhea or nausea/vomiting were more likely to have severe COVID-19. The liver-specific factors associated with independent risk of higher overall mortality were alcohol-related liver disease (ALD) (hazard ratio [HR] 2.42, 95% confidence interval [CI] 1.29-4.55), decompensated cirrhosis (HR 2.91 [1.70-5.00]) and hepatocellular carcinoma (HCC) (HR 3.31 [1.53-7.16]). Other factors were increasing age, diabetes, hypertension, chronic obstructive pulmonary disease and current smoker. Hispanic ethnicity (odds ratio [OR] 2.33 [1.47-3.70]) and decompensated cirrhosis (OR 2.50 [1.20-5.21]) were independently associated with risk for severe COVID-19. CONCLUSIONS: The risk factors which predict higher overall mortality among patients with CLD and COVID-19 are ALD, decompensated cirrhosis and HCC. Hispanic ethnicity and decompensated cirrhosis are associated with severe COVID-19. Our results will enable risk stratification and personalization of the management of patients with CLD and COVID-19. Clinicaltrials.gov number NCT04439084.

Discovery and Validation of a Biomarker Model (PRESERVE) Predictive of Renal Outcomes After Liver Transplantation.

BACKGROUND AND AIMS: A high proportion of patients develop chronic kidney disease (CKD) after liver transplantation (LT). We aimed to develop clinical/protein models to predict future glomerular filtration rate (GFR) deterioration in this population. APPROACH AND RESULTS: In independent multicenter discovery (CTOT14) and single-center validation (BUMC) cohorts, we analyzed kidney injury proteins in serum/plasma samples at month 3 after LT in recipients with preserved GFR who demonstrated subsequent GFR deterioration versus preservation by year 1 and year 5 in the BUMC cohort. In CTOT14, we also examined correlations between serial protein levels and GFR over the first year. A month 3 predictive model was constructed from clinical and protein level variables using the CTOT14 cohort (n = 60). Levels of ß-2 microglobulin and CD40 antigen and presence of hepatitis C virus (HCV) infection predicted early (year 1) GFR deterioration (area under the curve [AUC], 0.814). We observed excellent validation of this model (AUC, 0.801) in the BUMC cohort (n = 50) who had both early and late (year 5) GFR deterioration. At an optimal threshold, the model had the following performance characteristics in CTOT14 and BUMC, respectively: accuracy (0.75, 0.8), sensitivity (0.71, 0.67), specificity (0.78, 0.88), positive predictive value (0.74, 0.75), and negative predictive value (0.76, 0.82). In the serial CTOT14 analysis, several proteins, including ß-2 microglobulin and CD40, correlated with GFR changes over the first year. CONCLUSIONS: We have validated a clinical/protein model (PRESERVE) that early after LT can predict future renal deterioration versus preservation with high accuracy. This model may help select recipients at higher risk for subsequent CKD for early, proactive renal sparing strategies.

Liver Injury in Liver Transplant Recipients With Coronavirus Disease 2019 (COVID-19): U.S. Multicenter Experience.

BACKGROUND AND AIMS: Coronavirus disease 2019 (COVID-19) is associated with liver injury, but the prevalence and patterns of liver injury in liver transplantation (LT) recipients with COVID-19 are open for study. APPROACH AND RESULTS: We conducted a multicenter study in the United States of 112 adult LT recipients with COVID-19. Median age was 61 years (interquartile range, 20), 54.5% (n = 61) were male, and 39.3% (n = 44) Hispanic. Mortality rate was 22.3% (n = 25); 72.3% (n = 81) were hospitalized and 26.8% (n = 30) admitted to the intensive care unit (ICU). Analysis of peak values of alanine aminotransferase (ALT) during COVID-19 showed moderate liver injury (ALT 2-5× upper limit of normal [ULN]) in 22.2% (n = 18) and severe liver injury (ALT > 5× ULN) in 12.3% (n = 10). Compared to age- and sex-matched nontransplant patients with chronic liver disease and COVID-19 (n = 375), incidence of acute liver injury was lower in LT recipients (47.5% vs. 34.6%; P = 0.037). Variables associated with liver injury in LT recipients were younger age (P = 0.009; odds ratio [OR], 2.06; 95% confidence interval [CI], 1.20-3.54), Hispanic ethnicity (P = 0.011; OR, 6.01; 95% CI, 1.51-23.9), metabolic syndrome (P = 0.016; OR, 5.87; 95% CI, 1.38-24.99), vasopressor use (P = 0.018; OR, 7.34; 95% CI, 1.39-38.52), and antibiotic use (P = 0.046; OR, 6.93; 95% CI, 1.04-46.26). Reduction in immunosuppression (49.4%) was not associated with liver injury (P = 0.156) or mortality (P = 0.084). Liver injury during COVID-19 was significantly associated with mortality (P = 0.007; OR, 6.91; 95% CI, 1.68-28.48) and ICU admission (P = 0.007; OR, 7.93; 95% CI, 1.75-35.69) in LT recipients. CONCLUSIONS: Liver injury is associated with higher mortality and ICU admission in LT recipients with COVID-19. Hence, monitoring liver enzymes closely can help in early identification of patients at risk for adverse outcomes. Reduction of immunosuppression during COVID-19 did not increase risk for mortality or graft failure.

A comparison of surgical resection and liver transplantation in the treatment of intrahepatic cholangiocarcinoma in the era of modern chemotherapy: An analysis of the National Cancer Database.

BACKGROUND: The main surgical approach to patients with localized intrahepatic cholangiocarcinoma (ICC) is hepatectomy, but transplantation has been described. A comparison of outcomes between these surgical approaches is necessary to determine if one is preferable. METHODS: Patients with ICC were identified using the National Cancer Database (2010-2016). Patients were grouped based on operation and matched 1:1 by propensity score. Pathologic and postoperative outcomes, as well as overall survival were analyzed. RESULTS: There were 1879 hepatectomy and 74 liver transplantation patients. Before matching, transplantation patients were younger and more often treated at academic centers. More patients who underwent a transplantation received neoadjuvant chemotherapy (70.3% vs. 12.8%). Patients who underwent transplantation had more pathologic T0 (7.7% vs. 0.4%) and T1 (47.7% vs. 42.1%) tumors (p < .001). There were no differences in length of stay, unplanned readmissions, 30/90-day mortality, or median survival between groups (36.1 vs. 36.1 months, p = .34). After matching (n = 57/group), there were no differences in postoperative outcomes or survival between transplantation or hepatectomy (36.1 vs. 33.6 months, p = .57). CONCLUSION: Among patients with ICC, hepatectomy and liver transplantation were associated with similar postoperative outcomes and survival. In light of the resources and chronic immunosuppression required for transplantation, hepatectomy seems preferable for localized ICC.

Management of disappearing colorectal liver metastases: an international survey.

BACKGROUND: Improved chemotherapy response rates have lead to "disappearing" colorectal liver metastases (dCRLM). We aim to assess management patterns of dCRLM from an international body of hepatobiliary surgeons. METHODS: A survey was designed, tested for item relevance, readability and content validity, and distributed to the AHPBA, IHPBA and ANZHPBA. RESULTS: The majority of 226 respondents were <15 years from training (69%), practiced in academia (82%) and devoted >50% of their practice to hepatobiliary (75%). Surgeons utilize CT(45%) or MRI(47%) for preoperative planning with a preferred imaging interval of <6 weeks. Nearly all have experienced dCRLM (99%) and 63% of surgeons have waited a few months to assess for durability of response prior to definitive surgical/ablative therapy. Only 24% place fiducial markers for lesions <1-cm prior to neoadjuvant chemotherapy. Intra-operatively, 97% of surgeons perform ultrasound, and 71% ablation. When a tumor has "disappeared," 49% elect for observation and 31% resect if the dCRLM is superficial. Of those electing observation, 87% believe there is effective treatment with progression on surveillance imaging. CONCLUSIONS: Nearly all surgeons have experienced dCRLM with half choosing observation over intervention due to the belief that these lesions may be re-addressed in the future.

Management of early hepatocellular carcinoma: results of the Delphi consensus process of the Americas Hepato-Pancreato-Biliary Association.

BACKGROUND: There are many potential treatment options for patients with early stage hepatocellular carcinoma (HCC) and practice patterns vary widely. This project aimed to use a Delphi conference to generate consensus regarding the management of small resectable HCC. METHODS: A base case was established with review by members of AHPBA Research Committee. The Delphi panel of experts reviewed the literature and scored clinical case statements to identify areas of agreement and disagreement. Following initial scoring, discussion was undertaken, questions were amended, and scoring was repeated. This cycle was repeated until no further likelihood of reaching consensus existed. RESULTS: The panel achieved agreement or disagreement consensus regarding 27 statements. The overarching themes included that resection, ablation, transplantation, or any locoregional therapy as a bridge to transplant were all appropriate modalities for early or recurrent HCC. For larger lesions, consensus was reached that radiofrequency ablation and microwave ablation were not appropriate treatments. CONCLUSION: Using a validated system for identifying consensus, an expert panel agreed that multiple treatment modalities are appropriate for early stage HCC. These consensus guidelines are intended to help guide physicians through treatment modalities for early HCC; however, clinical decisions should continue to be made on a patient-specific basis.

Discovery and validation of a novel blood-based molecular biomarker of rejection following liver transplantation.

Noninvasive biomarker profiles of acute rejection (AR) could affect the management of liver transplant (LT) recipients. Peripheral blood was collected following LT for discovery (Northwestern University [NU]) and validation (National Institute of Allergy and Infectious Diseases Clinical Trials in Organ Transplantation [CTOT]-14 study). Blood gene profiling was paired with biopsies showing AR or ADNR (acute dysfunction no rejection) as well as stable graft function samples (Transplant eXcellent-TX). CTOT-14 subjects had serial collections prior to AR, ADNR, TX, and after AR treatment. NU cohort gene expression (46 AR, 45 TX) was analyzed using random forest models to generate a classifier training set (36 gene probe) distinguishing AR vs TX (area under the curve 0.92). The algorithm and threshold were locked and tested on the CTOT-14 validation cohort (14 AR, 50 TX), yielding an accuracy of 0.77, sensitivity 0.57, specificity 0.82, positive predictive value (PPV) 0.47, and negative predictive value (NPV) 0.87 for AR vs TX. The probability score line slopes were positive preceding AR, and negative preceding TX and non-AR (TX + ADNR) (P ≤ .001) and following AR treatment. In conclusion, we have developed a blood biomarker diagnostic for AR that can be detected prior to AR-associated graft injury as well a normal graft function (non-AR). Further studies are needed to evaluate its utility in precision-guided immunosuppression optimization following LT.

Peroxisomal footprint in the pathogenesis of nonalcoholic steatohepatitis.

Nonalcoholic steatohepatitis (NASH) is a form of fatty liver disease where benign hepatic steatosis leads to chronic inflammation in the steatotic liver of a patient without any history of alcohol abuse. Mechanisms underlying the progression of hepatic steatosis to NASH have long been investigated. This review outlines the potential role of peroxisomal dysfunctions in exacerbating the disease in NASH. Loss of peroxisomes as well as impaired peroxisomal functions have been demonstrated to occur in inflammatory conditions including NASH. Because peroxisomes and mitochondria co-operatively perform many metabolic functions including O2 and lipid metabolisms, a compromised peroxisomal biogenesis and function can potentially contribute to defective lipid and reactive oxygen species metabolism which in turn can lead the progression of disease in NASH. Impaired peroxisomal biogenesis and function may be due to the decreased expression of peroxisomal proliferator-activated receptor-α (PPAR-α), the major transcription factor of peroxisomal biogenesis. Recent studies indicate that the reduced expression of PPAR-α in NASH is correlated with the activation of the toll-like receptor-4 pathway (TLR-4). Further investigations are required to establish the mechanistic connection between the TLR-4 pathway and PPAR-α-dependent impaired biogenesis/function of peroxisomes in NASH.

Natural immunoglobulin M initiates an inflammatory response important for both hepatic ischemia reperfusion injury and regeneration in mice.

Complement plays a role in both hepatic ischemia reperfusion (IR) injury (IRI) and liver regeneration, but it is not clear how complement is activated in either process. We investigated the role of self-reactive immunoglobulin M (IgM) antibodies in activating complement after hepatic IR and liver resection. Natural IgM antibodies that recognize danger-associated molecular patterns (neoepitopes) activate complement following both hepatic IR and liver resection. Antibody-deficient Rag1-/- mice were protected from hepatic IRI, but had increased hepatic injury and an impaired regenerative response after 70% partial hepatectomy (PHx). We identified two IgM monoclonal antibodies (mAbs) that specifically reversed the effect of Rag1 deficiency in both models; B4 (recognizes Annexin IV) and C2 (recognizes subset of phospholipids). Focusing on the B4-specific response, we demonstrated sinusoidal colocalization of IgM and C3d in Rag1-/- mice that were reconstituted with B4 mAb, and furthermore that the Annexin IV neoepitope is specifically and similarly expressed after both hepatic IR and PHx in wild-type (WT) mice. A single-chain antibody construct (scFv) derived from B4 mAb blocked IgM binding and reduced injury post-IR in WT mice, although, interestingly, B4scFv did not alter regeneration post-PHx, indicating that anti-Annexin IV antibodies are sufficient, but not necessary, for the regenerative response in the context of an entire natural antibody repertoire. We also demonstrated expression of the B4 neoepitope in postischemic human liver samples obtained posttransplantation and a corollary depletion in IgM recognizing the B4 and C2 neoepitopes in patient sera following liver transplantation. Conclusion: These data indicate an important role for IgM in hepatic IRI and regeneration, with a similar cross-species injury-specific recognition system that has implications for the design of neoepitope targeted therapeutics. (Hepatology 2018;67:721-735).

Does attending a Delphi consensus conference impact surgeon attitudes? Survey results from the Americas HepatoPancreatoBiliary Association consensus conference on small asymptomatic pancreatic neuroendocrine tumors.

BACKGROUND: Management of asymptomatic small well-differentiated (panNET) <2 cm remains controversial. A consensus conference was held on this topic. The impact of attending the conference and participating in the audience response survey on surgeon's clinical approach to pancreatic neuroendocrine tumors was assessed. METHODS: Audience members were surveyed using a smartphone real-time response system at the beginning and end of the conference. RESULTS: The majority of 75 attendees underwent fellowship training, and 30% had >10 years experience as attending surgeons. Previously published consensus statements on the topic were considered insufficient to guide surgical practice by 82% of attendees, and over 96% desired additional data. After review of the data, consensus statements, and decision-making process, a significant number of participants changed their opinions regarding indications for tissue biopsy (p = 0.001), size thresholds for excision (p = 0.002), and regional lymph node dissection (p = 0.002) independent of whether a consensus was reached by the content-expert panel. CONCLUSIONS: This represented the first Delphi process consensus on the topic, and the survey confirmed the topic as well-chosen and timely. Attendees changed opinions on management of panNET regardless of whether formal consensus was reached. Therefore, statements of consensus combined with presentation of literature and live discussion served to impact attendees' approach to this disease.

Management of asymptomatic, well-differentiated PNETs: results of the Delphi consensus process of the Americas Hepato-Pancreato-Biliary Association.

BACKGROUND: Variation in the management of PNETs exist due to the limited high-level evidence to guide clinical practice. The aim of this work is to generate consensus guidelines with a Delphi process for managing PNETs. METHODS: A panel of experts reviewed the surgical literature and scored a set of clinical case statements using a web-based survey to identify areas of agreement and disagreement. Results of the survey were discussed after each round of review. This cycle was repeated until no further likelihood of reaching consensus existed. RESULTS: Twenty-two case statements related to surgical indications, preoperative biopsy, extent of resection, type of surgery, and tumor location were scored. Using a pre-defined definition of consensus, the panel achieved consensus on the following: i) resection is not recommended for <1 cm lesions; ii) resection is recommended for lesions greater than 2 cm; iii) lymph node dissection is recommended for radiographically-suspicious nodes with splenectomy for distal lesions; iv) tumor enucleation and central pancreatectomy are acceptable when technically feasible. No consensus was reached regarding issues of preoperative biopsy or 1-2 cm tumors. CONCLUSIONS: Using a structured, validated system for identifying consensus, an expert panel identified areas of agreement regarding critical management decisions for patients with PNET. Issues without consensus warrant additional clinical investigation.

Lipid metabolism and functional assessment of discarded human livers with steatosis undergoing 24 hours of normothermic machine perfusion.

Normothermic machine perfusion (NMP) is an emerging technology to preserve liver allografts more effectively than cold storage (CS). However, little is known about the effect of NMP on steatosis and the markers indicative of hepatic quality during NMP. To address these points, we perfused 10 discarded human livers with oxygenated NMP for 24 hours after 4-6 hours of CS. All livers had a variable degree of steatosis at baseline. The perfusate consisted of packed red blood cells and fresh frozen plasma. Perfusate analysis showed an increase in triglyceride levels from the 1st hour (median, 127 mg/dL; interquartile range [IQR], 95-149 mg/dL) to 24th hour of perfusion (median, 203 mg/dL; IQR, 171-304 mg/dL; P = 0.004), but tissue steatosis did not decrease. Five livers produced a significant amount of bile (≥5 mL/hour) consistently throughout 24 hours of NMP. Lactate in the perfusate cleared to <3 mmol/L in most livers within 4-8 hours of NMP, which was independent of bile production rate. This is the first study to characterize the lipid profile and functional assessment of discarded human livers at 24 hours of NMP. Liver Transplantation 24 233-245 2018 AASLD.

Assessment of risk factors for increased resource utilization in kidney transplantation.

BACKGROUND: There are only a limited number of studies that have sought to identify patients at high risk for medication errors and subsequent adverse clinical outcomes. This study sought to identify risk factors for increased health care resource utilization in kidney transplant recipients based on drug-related problems and self-administered surveys. METHODS: In this prospective observational study, adult kidney transplant recipients seen in the transplant clinic between September and November 2015 were surveyed for self-reported demographics, medication adherence, and health status/outlook. Subsequently, patients were assessed for associations between survey results, pharmacist-derived drug-related problems, and health resource utilization over a minimum 6-mo follow-up period. Based on univariate associations, two risk cohorts were identified and compared for health care utilization using multivariable Poisson regression. RESULTS: A total of 237 patients were included, with a mean follow-up of 8 mo. From the patient survey data, Medicaid insured or self-rated poor health status were identified as a significant risk cohort. From pharmacist assessments, those who received incorrect medication or lacked appropriate follow-up medication monitoring were identified as a significant risk cohort (pharmacy errors). The Medicaid insured or self-rated poor health status cohort experienced 43% more total health care encounters (incident rate ratios [IRR] 1.43, 1.01-2.02) and 35% more transplant clinic visits (IRR 1.35, 1.03-1.77). The pharmacy errors cohort experienced 4.2 times the rate of total health care encounters (IRR 4.17, 1.55-11.2), 4.1 times the rate of hospital readmissions (IRR 4.09, 1.58-10.6), and 2.3 times the rate of transplant clinic visits (IRR 2.31, 1.04-5.11). CONCLUSIONS: Medicaid insurance, self-rated poor health status, and errors in the medication regimen or monitoring were significant risk factors for increased health care utilization in kidney transplant recipients. Further research is warranted to validate these potential risk factors, determine the long-term impact on graft/patient survival, and assess the mutability of these risks through prospective identification and intervention.

Safety and benefits of new techniques and technologies in less invasive mitral valve repair.

OBJECTIVE: To assess the safety and benefits of new techniques and technologies such as single-dose (del Nido) cardioplegia and suture fasteners (COR-KNOT) in patients undergoing mini-thoracotomy for degenerative mitral valve repair (MVR). METHODS: From 2009 to 2016, 252 patients underwent primary isolated degenerative MVR by mini-thoracotomy by a single surgeon. Del Nido cardioplegia was used in 153 patients (61%) and COR-KNOT in 168 (67%). Patient outcomes were compared using propensity-matching separately for del Nido versus Buckberg cardioplegia and COR-KNOT versus knot-pusher. RESULTS: There were no operative deaths and 99.2% of the patients had none/trivial mitral regurgitation at discharge. In patients receiving del Nido or Buckberg cardioplegia, occurrence of adverse events was similar. However, aortic cross clamp (AoCC; 54.2 ± 15.7 vs 64 ± 15.8 min; P < 0.0001) and operative room (OR; 308 ± 42.1 vs 336 ± 63 min; P < 0.001) times were shorter with del Nido cardioplegia. In patients receiving COR-KNOT versus knot-pusher, occurrence of adverse events was similar. However, AoCC (54.1 ± 15.2 vs 66.1 ± 15.9 min; P < 0.0001) and OR (311 ± 43.6 vs 336 ± 65.4 min; P < 0.0001) times were shorter with COR-KNOT. Results were similar after matching for both, del Nido versus Buckberg cardioplegia and COR-KNOT versus knot-pusher. CONCLUSION: New techniques and technologies, such as del Nido cardioplegia and COR-KNOT, decrease AoCC and OR times without compromising patient safety.

Use of intra-aortic counterpulsation in cardiogenic shock post-liver transplantation.

Left ventricular dysfunction resulting in cardiogenic shock occurs infrequently following organ reperfusion in liver transplantation. The etiology of the cardiogenic shock is often multifactorial and difficult to manage due to the complex nature of the procedure and the patient's baseline physiology. Traditionally, this hemodynamic instability is managed medically using inotropic agents and vasopressor support. If medical treatment is insufficient, the use of an intra-aortic balloon pump for counterpulsation may be employed to improve the hemodynamics and stabilize the patient. Here, we analyze three cases and review the literature.