Cirrhotics admitted to intensive care unit: the impact of acute renal failure on mortality

Acute Kidney Injury and Hepatorenal Syndrome in Patients with Cirrhosis

Acute kidney injury (AKI) is common in hospitalized patients with cirrhosis. Hepatorenal syndrome (HRS) is a type of AKI known as HRS-AKI. It is a severe complication of cirrhosis with high morbidity and mortality. While certain vasoconstrictor medications have been shown to improve HRS-AKI, no clear transplant-free survival benefit has been reported with medical therapies. Patients with HRS-AKI should be considered for urgent liver transplantation evaluation. In this review, we discuss the most recent updates on the definition, diagnosis, and management of AKI in cirrhosis, with special a emphasis on HRS.

Cirrhosis Management in the Intensive Care Unit

Patients with cirrhosis frequently require admission to the intensive care unit as complications arise in the course of their disease. These admissions are associated with high short- and long-term morbidity and mortality. Thus, understanding and characterizing complications and unique needs of patients with cirrhosis and acute-on-chronic liver failure helps providers identify appropriate level of care and evidence-based treatments. While there is no widely accepted critical care admission criteria for patients with cirrhosis, the presence of organ failure and primary or nosocomial infections are associated with particularly high in-hospital mortality. Optimal management of patients with cirrhosis in the critical care setting requires a system-based approach that acknowledges deviations from canonical pathophysiology. In this review, we discuss appropriate considerations and evidence-based practices for the general care of patients with cirrhosis and critical illness.

Impact of acute kidney injury on the risk of mortality in patients with cirrhosis: a systematic review and meta-analysis

Objective

To compare the risk of mortality in patients with cirrhosis with and without the associated acute kidney injury (AKI).

Methods

We performed a systematic search in the PubMed, Embase, and Scopus databases for observational studies that were done on patients with cirrhosis. Eligible studies reported AKI in patients with cirrhosis and compared mortality among patients with and without AKI. We used a random-effects model, using STATA version 16.0, for deriving pooled effect sizes that were reported as odds ratio (OR) with 95% confidence intervals (CIs).

Results

Thirty-two studies were included. In patients with cirrhosis, AKI was significantly associated with higher in-hospital mortality (OR 5.92), and mortality at 30 days (OR 4.78), 90 days (OR 4.34), and at 1 year follow-up (OR 4.82) compared to patients without AKI.

Conclusions

AKI is associated with an increased risk of mortality in patients with cirrhosis. Careful monitoring to identify the development of AKI and early prompt management is necessary.

Update on hepatorenal Syndrome: Definition, Pathogenesis, and management

Hepatorenal syndrome (HRS) is acute kidney injury (AKI) that occurs without evidence of structural abnormalities in the kidneys in patients with liver disease. It is thought to be due to splanchnic vasculature dilatation that is associated with intense increase of renal arteries' tone, leading to renal cortex ischemia and AKI. Nitric oxide, endotoxins, neurohormonal changes, bacterial infection, high serum bilirubin and bile acids are examples for factors contributing to HRS development. Nevertheless, other unknown factors may have role in HRS pathophysiology. Hence, further discussion and research are needed to clearly understand HRS. Plasma volume restoration and vasoconstrictors are the cornerstone of HRS treatment. Others such as octreotide, noradrenaline, infection control, systemic inflammatory response prevention, shunting, and renal replacement therapy are currently used to manage HRS. Liver or combined liver and kidney transplantation is currently the ultimate cure for HRS. This review was written to help in better understanding the pathogenesis, diagnosis, and treatment options for HRS.

Management of acute renal replacement therapy in critically ill cirrhotic patients

Renal replacement therapy (RRT) in cirrhotic patients encompasses a number of issues related to the particular characteristics of this population, especially in the intensive care unit (ICU) setting. The short-term prognosis of cirrhotic patients with acute kidney injury is poor, with a mortality rate higher than 65% in patients with RRT requirement, raising questions about the futility of its initiation. Regarding the management of the RRT itself, there is still no consensus with respect to the modality (continuous versus intermittent) or the anticoagulation required to improve the circuit life, which is shorter than similar at-risk populations, despite the altered haemostasis in traditional coagulation tests frequently found in these patients. Furthermore, volume management is one of the most complex issues in this cohort, where tools used for ambulatory dialysis have not yet been successfully reproducible in the ICU setting. This review attempts to shed light on the management of acute RRT in the critically ill cirrhotic population based on the current evidence and the newly available tools. We will discuss the timing of RRT initiation and cessation, the modality, anticoagulation and fluid management, as well as the outcomes of the RRT in this population, and provide a brief review of the albumin extracorporeal dialysis from the point of view of a nephrologist.

Predictors of Development of Hepatorenal Syndrome in Hospitalized Cirrhotic Patients with Acute Kidney Injury

Hepatorenal syndrome (HRS) is a type of acute kidney injury (AKI), occurring in patients with decompensated liver cirrhosis and is associated with high mortality. We aim to describe the predictors associated with the development of HRS in cirrhotic patients with AKI. We retrospectively analyzed 529 cirrhotic patient encounters with AKI across all Northwell Health institutions between 1 January 2015 and 31 December 2018. We performed multivariate analyses to determine independent predictors of development of HRS. Alcoholic cirrhosis was the most common identified etiology of cirrhosis. The mean Model for End-Stage Liver Disease Scorewas18 (±7). Ascites was the most commonly identified clinical feature of portal hypertension. Infection was identified in 38.4% of patients with urinary tract infection/pyelonephritis being the most common. Spontaneous bacterial peritonitis occurred in 5.9% of patients. The most common cause of AKI was pre-renal. Hepatorenal syndrome was identified in 9.8% of patient encounters. Predictors of HRS were history of ascites, serum creatinine >2.5 mg/dL, albumin <3 g/dL, bilirubin >2 mg/dL and spontaneous bacterial peritonitis. We demonstrate strong predictors for the development of HRS which can aid clinicians to attain an early diagnosis of HRS, leading to prompt and targeted management and improving outcomes.

Cystatin C: best biomarker for acute kidney injury and estimation of glomerular filtration rate in childhood cirrhosis

The objective of the study was to evaluate the diagnostic and prognostic role of serum cystatin C, urinary neutrophil gelatinase-associated lipocalin (NGAL), and renal resistive index (RRI) in AKI among pediatric cirrhotics. The study included cirrhotic children under 18 years of age. AKI was diagnosed as per Kidney Diseases-Improving Global Outcomes (KDIGO) guidelines. All patients underwent measurement of serum cystatin C, urinary NGAL, and RRI at baseline, 3 months, and 6 months. eGFR was calculated using both creatinine- and cystatin-based equations. Of the 247 cirrhotics admitted during the study, 100 gave consent and were included. Forty-one fulfilled the KDIGO definition of AKI of whom 22 showed resolution. Two of these children had a repeat AKI at 2 and 4 months after initial AKI; both resolved with medical management. On logistic regression analysis, serum cystatin C (OR: 544.8, 95% CI: 24.4-12170, p < 0.0005) and urinary NGAL (OR: 1.006, 95% CI: 1001-1.012, p = 0.019) were found to be significantly associated with AKI. Cystatin C alone was the best biomarker for diagnosing AKI in children with decompensation (OR: 486.7, p < 0.0005) or spontaneous bacterial peritonitis (p = 0.02). eGFR calculated by serum cystatin C-based formulas was more reliable than that calculated by creatinine-based equations.Conclusion: Serum cystatin C is the best biomarker for diagnosis of AKI in pediatric cirrhotics, especially with decompensation and SBP. eGFR calculated on serum cystatin C-based equations is more reliable than creatinine-based ones. What is Known: • Acute kidney injury (AKI) is a common complication in cirrhotic adults. • Newer biomarkers have diagnostic and prognostic role in adult cirrhotics. What is New: • Serum cystatin C is a useful biomarker to identify acute kidney injury in cirrhotic children with decompensation. • Glomerular filtration rate calculation is more accurate by cystatin-based equations than creatinine-based equations.

Assessing the prognosis of cirrhotic patients in the intensive care unit: What we know and what we need to know better

Critically ill cirrhotic patients have high in-hospital mortality and utilize significant health care resources as a consequence of the need for multiorgan support. Despite this fact, their mortality has decreased in recent decades due to improved care of critically ill patients. Acute-on-chronic liver failure (ACLF), sepsis and elevated hepatic scores are associated with increased mortality in this population, especially among those not eligible for liver transplantation. No score is superior to another in the prognostic assessment of these patients, and both liver-specific and intensive care unit-specific scores have satisfactory predictive accuracy. The sequential assessment of the scores, especially the Sequential Organ Failure Assessment (SOFA) and Chronic Liver Failure Consortium (CLIF)-SOFA scores, may be useful as an auxiliary tool in the decision-making process regarding the benefits of maintaining supportive therapies in this population. A CLIF-ACLF > 70 at admission or at day 3 was associated with a poor prognosis, as well as SOFA score > 19 at baseline or increasing SOFA score > 72. Additional studies addressing the prognostic assessment of these patients are necessary.

Co-orchestration of acute kidney injury and non-kidney organ failures in critically ill patients with cirrhosis

BACKGROUND & AIMS

Little is known on the course of acute kidney injury (AKI) and its relation to non-kidney organ failures and mortality in critically ill patients with cirrhosis (CICs).

METHODS

We conducted a large prospective, single-centre, observational study in which CICs were followed up daily, during the first 7 days of intensive care, collecting prespecified criteria for AKI, extrarenal extrahepatic organ failures (ERH-OFs) and systemic inflammatory response syndrome (SIRS).

RESULTS

A total of 291 patients admitted to ICU were enrolled; 231 (79.4%) had at least one ERH-OFs, 168 (58%) had AKI at presentation, and 145 (49.8%) died by 28 days. At day seven relative to baseline, 151 (51.8%) patients had progressive or persistent AKI, while the rest remained free of AKI or had AKI improvement. The 28-day mortality rate was higher among patients with progressive/persistent AKI (74.2% vs 23.5%; P < .001) or maximum stage 3 of AKI in the first week. Two-level mixed logistic regression modelling identified independent baseline risk factors for progressive/persistent AKI, including 3 to 4 SIRS criteria, infections due to multidrug-resistant bacteria (MDR), elevated serum bilirubin, and number of ERH-OFs. Follow-up risk factors included increases in bilirubin and chloride levels, and new development of 2 or 3 ERH-OFs.

CONCLUSIONS

Our results show that among CICs admitted to the ICU, the stage and course of AKI in the first week determines outcomes. Strategies combating MDR infections, multiorgan failure, liver failure and intense systemic inflammation could prevent AKI progression or persistence in CICs.

Renal Failure is Associated With Increased Mortality and Hospital Utilization in Patients Admitted With Nonalcoholic Steatohepatitis

GOALS

We aimed to investigate the mortality and hospital utilization outcomes of hospitalized nonalcoholic steatohepatitis (NASH) patients with and without kidney failure in a nationwide cohort.

BACKGROUND

NASH is a common medical condition associated with significant morbidity and mortality. A paucity of data exists regarding the impact of kidney failure (defined as acute and chronic kidney failure) on outcomes of NASH hospitalizations.

MATERIALS AND METHODS

We conducted a retrospective cohort study using the 2016 Nationwide Inpatient Sample dataset of adult patients hospitalized for NASH, stratified for the presence of renal failure. The primary outcome was inpatient mortality, predictors were analyzed using multivariate logistic regression. Secondary outcomes were the length of stay and mean total hospitalization charges.

RESULTS

The overall sample included 7,135,090 patients. Among 6855 patients admitted for NASH, 598 or 8.7% had comorbid kidney failure. After multivariate regression analysis, NASH patients with renal failure had increased in-hospital mortality [odds ratio=28.72, 95% confidence interval (CI): 8.99-91.73], length of stay (β=3.02, 95% CI: 2.54-3.5), total hospital charges (β=$37,045, 95% CI: $31,756.18-$42,335.62). Positive predictors of mortality in the renal failure group were Charlson Comorbidity Index ≥3 [adjusted odds ratio (aOR)=3.46, 95% CI: 1.04-11.51], variceal bleeding (aOR=3.02, 95% CI: 1.06-8.61), and hepatic encephalopathy (aOR=26.38, 95% CI: 1.29-540.56). Predictors of decreased mortality were Medicaid (aOR=0.047, 95% CI: 0.28-0.79) and private insurance (aOR=0.56, 95% CI: 0.38-0.83).

CONCLUSIONS

The prevalence of renal failure in NASH hospitalizations is associated with markedly increased mortality, hospital costs, and length of stay. As a result, clinicians should be vigilant in treating kidney failure in this population.

Intraoperative hypotension during liver transplant surgery is associated with postoperative acute kidney injury: a historical cohort study

Background

Acute kidney injury (AKI) occurs frequently after liver transplant surgery and is associated with significant morbidity and mortality. While the impact of intraoperative hypotension (IOH) on postoperative AKI has been well demonstrated in patients undergoing a wide variety of non-cardiac surgeries, it remains poorly studied in liver transplant surgery. We tested the hypothesis that IOH is associated with AKI following liver transplant surgery.

Methods

This historical cohort study included all patients who underwent liver transplant surgery between 2014 and 2019 except those with a preoperative creatinine > 1.5 mg/dl and/or who had combined transplantation surgery. IOH was defined as any mean arterial pressure (MAP) < 65 mmHg and was classified according to the percentage of case time during which the MAP was < 65 mmHg into three groups, based on the interquartile range of the study cohort: “short” (Quartile 1, < 8.6% of case time), “intermediate” (Quartiles 2–3, 8.6–39.5%) and “long” (Quartile 4, > 39.5%) duration. AKI stages were classified according to a “modified” “Kidney Disease: Improving Global Outcomes” (KDIGO) criteria. Logistic regression modelling was conducted to assess the association between IOH and postoperative AKI. The model was run both as a univariate and with multiple perioperative covariates to test for robustness to confounders.

Results

Of the 205 patients who met our inclusion criteria, 117 (57.1%) developed AKI. Fifty-two (25%), 102 (50%) and 51 (25%) patients had short, intermediate and long duration of IOH respectively. In multivariate analysis, IOH was independently associated with an increased risk of AKI (adjusted odds ratio [OR] 1.05; 95%CI 1.02–1.09; P < 0.001). Compared to “short duration” of IOH, “intermediate duration” was associated with a 10-fold increased risk of developing AKI (OR 9.7; 95%CI 4.1–22.7; P < 0.001). “Long duration” was associated with an even greater risk of AKI compared to “short duration” (OR 34.6; 95%CI 11.5-108.6; P < 0.001).

Conclusions

Intraoperative hypotension is independently associated with the development of AKI after liver transplant surgery. The longer the MAP is < 65 mmHg, the higher the risk the patient will develop AKI in the immediate postoperative period, and the greater the likely severity. Anesthesiologists and surgeons must therefore make every effort to avoid IOH during surgery.

Acute kidney injury is associated with higher mortality and healthcare costs in hospitalized patients with cirrhosis

INTRODUCTION AND OBJECTIVES

AKI is known to be associated with increased risk of mortality, however limited information is available on how AKI impacts healthcare costs and resource utilization in hospitalized patients with cirrhosis. Previous studies have had variable definitions of AKI, resulting in inconsistent reporting of the true impact of AKI in patients with cirrhosis.

METHODS

Data from the Nationwide Inpatient Sample (NIS) which contains data from 44 states and 4378 hospitals, accounting for over 7 million discharges were analyzed. The inclusion data were all discharges in the 2012 NIS dataset with a discharge diagnosis of cirrhosis.

RESULTS

A total of 32,605 patients were included in the analysis, incidence of AKI was 12.12% in patients with cirrhosis. Crude mortality was much higher for patients with cirrhosis and AKI (14.9% vs. 1.8%, OR 9.42, p<0.001) than for patients without AKI. In addition, mean LOS was longer (8.5 vs. 4.3 days, p<0.001) and median total hospital charges were higher for patients with AKI ($43,939 vs. $22,270, p<0.001). In multivariate logistic regression, controlling for covariates and mortality risk score, sepsis, ascites and SBP were predictors of AKI.

CONCLUSIONS

AKI is relatively common in hospitalized patients with cirrhosis. Presence of AKI results in significantly higher inpatient mortality as well as LOS and resource utilization. Median hospitalization cost was twice as high in AKI patients. Early identification of patients at high risk for AKI should be implemented to reduce mortality and contain costs. Prognosis could be enhanced by utilizing biomarkers which could rapidly detect AKI.

Incidence, Mortality and Predictors of Acute Kidney Injury in Patients with Cirrhosis: A Systematic Review and Meta-analysis

Background and Aims: Acute kidney injury (AKI) is common in patients with cirrhosis but the incidence is heterogeneous among studies. We performed a meta-analysis to describe the incidence of AKI and its impact on patient mortality in patients with cirrhosis. We also evaluated the admission variables predicting development of AKI. Methods: A systematic search of various databases was performed up to November 2018. Meta-analyses were performed using random effects models. Results: Of 18,474 patients with cirrhosis from 30 selected studies, 5,648 developed AKI, with a pooled incidence of 29% (95% confidence interval [CI]: 28-30%, I ² of 99%). In-hospital mortality assessed in eight studies was six-fold higher among AKI patients, as compared to those without AKI (odds ratio [OR] 6.72, 95% CI: 3.47-13, p<0.0001, I ² of 70%). Three studies on patients admitted to intensive care showed about six-fold higher mortality among AKI patients (OR 5.90, 95% CI: 3.21-10.85, p>0.0001). Mortality remained significantly high, at days 30 and 90 and even at 1-year follow up after development of AKI. Of 12 admission variables analyzed, model for end-stage liver disease score, Child-Pugh-Turcotte stage C, presence of ascites, and presence of sepsis/septic shock were statistically significant risk factors for AKI. Conclusions: AKI occurred in about 29% of patients with cirrhosis and is associated with a six-fold increased risk of in-hospital mortality. Mortality remained high even in long-term follow-up of 1 year. Patients at risk for AKI development can be recognized at admission. Prospective studies are needed to develop strategies for improving outcome of these patients.

Acute Kidney Injury After Pediatric Liver Transplantation

BACKGROUND

The aim of the present study is to assess acute kidney injury (AKI) incidence according to the pRIFLE and AKIN criteria and to evaluate the risk factors for early developing AKI in postoperative intensive care unit after pediatric liver transplantation (LT).

MATERIALS

After exclusion of retransplantations, 7 cadaveric and 44 living donors, totaling 51 pediatric LT patients that were performed between 2005 and 2017, were reviewed retrospectively. AKI was defined according to both pediatric RIFLE (Risk for renal dysfunction, Injury to the kidney, Failure of kidney function, Loss of kidney function, and End-stage renal disease) and Acute Kidney Injury Network (AKIN) criteria. Documented data were compared between AKI and non-AKI patients.

RESULTS

AKI incidences were 17.6% by AKIN and 37.8% by pRIFLE criteria. AKIN-defined AKI group had statistically lower serum albumin level, higher serum sodium level, higher furosemide dose, and higher rate of red blood cell (RBC) transfusion than the non-AKI group (P = .02, P = .02, P = .01 and P = .04, respectively). AKI patients had significantly prolonged mechanical ventilation (P = .01) and hospital LOS (P = .02). The pRIFLE-defined AKI group had significantly lower serum albumin level, higher blood urea nitrogen (BUN) level, and higher ascites drained and also showed higher requirement for RBC and 20% human albumin transfusions than the non-AKI group (P = .02, P = .04, P: =.007, P = .02 and P = .05, respectively).

CONCLUSION

We evaluated that hypoalbuminemia, high requirement for RBC and 20% human albumin transfusions, high serum sodium, high furosemide use, and high flow of ascites are risk factors for AKI and high BUN levels can be predictive for AKI in pediatric LT patients. The effect of AKI on outcome variables were prolonged mechanical ventilation and hospital LOS.

Factors associated with renal dysfunction in hepatitis C-related cirrhosis and its correlation with Child-Pugh score

Objectives

To assess factors associated with renal dysfunction (RD) in hepatitis C virus (HCV) cirrhosis, correlate renal parameters with Child-Pugh score (CPS) and find a cut-off value of CPS to determine RD.

Materials and methods

It was a cross-sectional study that included 70 cases of liver cirrhosis secondary to HCV from a period of 6 months at Combined Military Hospital, Multan. Diagnosis of HCV was confirmed by serological assay and liver cirrhosis by ultrasonography. CPS was determined and lab reports were taken. Patients were divided into two groups as not having RD (serum creatinine≤1.5 mg/dL) and having RD (serum creatinine≥1.5 mg/dL). Estimated glomerular filtration rate (eGFR) was calculated by chronic kidney disease epidemiology collaboration (CKD-EPI) formula. Data were analyzed using SPSS V.23.0. χ², Kruskal-Wallis test and Pearson coefficient of correlation were applied. ROC curve was drawn to evaluate cut-off value of CPS for the presence of RD. Level of significance was set at p<0.05.

Results

Patients with CP grade B or C develop RD as compared to patients with CP grade A (p=0.000). Mean age, urea, creatinine and eGFR varies significantly among patients who develop RD and patients who do not (p=0.02, p=0.000, p=0.000 and p=0.000, respectively). eGFR negatively correlates with CPS (r=−0.359, p=0.002). Creatinine, urea and ALBI score positively correlates with CPS (r=+0.417, p=0.000; r=+0.757, p=0.000; r=+0.362, p=0.002, respectively).

Conclusion

Ascites and encephalopathy are associated with RD in HCV cirrhosis.

Biomarkers for acute kidney injury in decompensated cirrhosis: A prospective study

AIM

Acute kidney injury (AKI) is a frequent complication in cirrhotic patients. As serum creatinine is a poor marker of renal function in this population, we aimed to study the utility of several biomarkers in this context.

METHODS

A prospective study was conducted in hospitalized patients with decompensated cirrhosis. Serum creatinine (SCr), Cystatin C (CystC), NGAL and urinary NGAL, KIM-1, protein, albumin and sodium were measured on three separate occasions. Renal resistive index (RRI) was obtained. We analyzed the value of these biomarkers to determine the presence of AKI, its aetiology [prerenal, acute tubular necrosis (ATN), or hepatorenal (HRS)], its severity and a composite clinical outcome at 30 days (death, dialysis and intensive care admission).

RESULTS

We included 105 patients, of which 55 had AKI. SCr, CystC, NGAL (plasma and urinary), urinary sodium and RRI at inclusion were independently associated with the presence of AKI. SCr, CystC and plasma NGAL were able to predict the subsequent development of AKI. Pre-renal state showed lower levels of SCr, NGAL (plasma and urinary) and RRI. ATN patients had high levels of NGAL (plasma and urinary) as well as urinary protein and sodium. HRS patients presented an intermediate pattern. All biomarkers paralleled the severity of AKI. SCr, CystC and plasma NGAL predicted the development of the composite clinical outcome with the same performance as the MELD score.

CONCLUSIONS

In patients with decompensated cirrhosis, early measurement of renal biomarkers provides valuable information on AKI aetiology. It could also improve AKI diagnosis and prognosis.

Evaluation of the criteria of hepatorenal syndrome type of acute kidney injury in patients with cirrhosis admitted to ICU

INTRODUCTION

Acute kidney injury (AKI) is a common and devastating complication in patients with cirrhosis. In 2015, the International Club of Ascites (ICA) proposed the definition of hepatorenal syndrome (HRS) type of AKI (HRS-AKI) in patients with cirrhosis. This study aims to evaluate the criteria of HRS-AKI in patients with cirrhosis admitted to ICU with regard to the prognosis.

METHODS

A total of 349 cirrhotic patients consecutively admitted to intensive care unit (ICU) from 2010 to 2017 were retrospectively analyzed. Demographic parameters and clinical variables were collected with case report forms. The occurrence of AKI was determined according to ICA-AKI criteria. The phenotypes of AKI comprised pre-renal azotemia (PRA), acute tubular necrosis (ATN) and HRS. In our study, patients with PRA or ATN were classified to the non-HRS-AKI group.

RESULTS

The incidence of AKI was 73.0%, comprising PRA (18.6%), ATN (16.3%) and HRS (38.1%). The overall hospital mortality was 64.5%. Patients with AKI had a significantly higher in-hospital (76.1%) and 180-d (86.7%) mortality. AKI type was an independent risk factor for in-hospital mortality by a multivariate logistic regression. The in-hospital and 180-d mortality rates were of no significant difference among patients with HRS-AKI stages 1-3.

CONCLUSIONS

AKI is common in patients with cirrhosis admitted to ICU, associated with significant in-hospital mortality. HRS-AKI was the most common and severe type of AKI in patients with cirrhosis admitted to ICU. The current staging system may not be applicable for HRS-AKI in patients with cirrhosis admitted to ICU.

Intensive Care Therapy for Patients with Advanced Liver Diseases

Decompensated cirrhosis is characterized by high hospitalization rates and costs, frequent readmissions, and poor short-term survival. Patients admitted to the hospital with acute variceal bleeding and/or hepatic encephalopathy and/or renal dysfunction are at serious risk for developing infection and/or sepsis; in turn, this renders them highly susceptible to the development of multi-system organ failure. The lack of standardized intensive care unit management protocols in patients with cirrhosis along with only few data reports from longitudinal clinical trials makes it difficult for hepatologists and critical care specialists to provide uniform evidence for clinical practice that could safely consolidate favorable outcomes such as lower hospitalization rates and/or mortality. Based on a rigorous online search of the scientific literature as well as a longtime clinical experience of the authors in the field of hepatology and critical care medicine, this work represents a focused effort to elucidate the specific bio-morbidity of advanced liver diseases in relation to the aforementioned challenges in clinical management. Further meta-analyses and/or systematic reviews are needed to enable clinicians to develop more effective strategies to bridge patients with decompensated liver disease to recompensation or liver transplantation.

Unique metabolomic signature associated with hepatorenal dysfunction and mortality in cirrhosis

The application of nontargeted metabolomic profiling has recently become a powerful noninvasive tool to discover new clinical biomarkers. This study aimed to identify metabolic pathways that could be exploited for prognostic and therapeutic purposes in hepatorenal dysfunction in cirrhosis. One hundred three subjects with cirrhosis had glomerular filtration rate (GFR) measured using iothalamate plasma clearance, and were followed until death, transplantation, or the last encounter. Concomitantly, plasma metabolomic profiling was performed using ultrahigh performance liquid chromatography-tandem mass spectrometry to identify preliminary metabolomic biomarker candidates. Among the 1028 metabolites identified, 34 were significantly increased in subjects with high liver and kidney disease severity compared with those with low liver and kidney disease severity. The highest average fold-change (2.39) was for 4-acetamidobutanoate. Metabolite-based enriched pathways were significantly associated with the identified metabolomic signature (P values ranged from 2.07E-06 to 0.02919). Ascorbate and aldarate metabolism, methylation, and glucuronidation were among the most significant protein-based enriched pathways associated with this metabolomic signature (P values ranged from 1.09E-18 to 7.61E-05). Erythronate had the highest association with measured GFR (R-square = 0.571, P <0.0001). Erythronate (R = 0.594, P <0.0001) and N6-carbamoylthreonyladenosine (R = 0.591, P <0.0001) showed stronger associations with measured GFR compared with creatinine (R = 0.588, P <0.0001) even after controlling for age, gender, and race. The 5 most significant metabolites that predicted mortality independent of kidney disease and demographics were S-adenosylhomocysteine (P = 0.0003), glucuronate (P = 0.0006), trans-aconitate (P = 0.0018), 3-ureidopropionate (P = 0.0021), and 3-(4-hydroxyphenyl)lactate (P = 0.0047). A unique metabolomic signature associated with hepatorenal dysfunction in cirrhosis was identified for further investigations that provide potentially important mechanistic insights into cirrhosis-altered metabolism.

New Developments in Hepatorenal Syndrome

Hepatorenal syndrome (HRS) continues to be one of the major complications of decompensated cirrhosis, leading to death in the absence of liver transplantation. Challenges in precisely evaluating renal function in the patient with cirrhosis remain because of the limitations of serum creatinine (Cr) alone in estimating glomerular filtration rate (GFR); current GFR estimating models appear to underestimate renal dysfunction. Newer models incorporating renal biomarkers, such as the Cr-Cystatin C GFR Equation for Cirrhosis appear to estimate measured GFR more accurately. A major change in the diagnostic criteria for HRS based on dynamic serial changes in serum Cr that regard HRS type 1 as a special form of acute kidney injury promises the possibility of earlier identification of renal dysfunction in patients with cirrhosis. The diagnostic criteria of HRS still include the exclusion of other causes of kidney injury. Renal biomarkers have been disappointing in assisting with the differentiation of HRS from prerenal azotemia and other kidney disorders. Serum metabolomic profiling may be a more powerful tool to assess renal dysfunction, although the practical clinical significance of this remains unclear. As a result of the difficulties of assessing renal function in cirrhosis and the varying HRS diagnostic criteria and the rigor with which they are applied, the precise incidence and prevalence of HRS is unknown, but it is likely that HRS occurs more commonly than expected. The pathophysiology of HRS is rooted firmly in the setting of progressive reduction in renal blood flow as a result of portal hypertension and splanchnic vasodilation. Progressive marked renal cortical ischemia in patients with cirrhosis parallels the evolution of diuretic-sensitive ascites to diuretic-refractory ascites and HRS, a recognized continuum of renal dysfunction in cirrhosis. Alterations in nitrous oxide production, both increased and decreased, may play a major role in the pathophysiology of this evolution. The inflammatory cascade, triggered by bacterial translocation and endotoxemia, increasingly recognized as important in the manifestation of acute-on-chronic liver failure, also may play a significant role in the pathophysiology of HRS. The mainstay of treatment remains vasopressor therapy with albumin in an attempt to reverse splanchnic vasodilation and improve renal blood flow. Several meta-analyses have confirmed the value of vasopressors, chiefly terlipressin and noradrenaline, in improving renal function and reversing HRS type 1. Other interventions such as renal replacement therapy, transjugular intrahepatic portosystemic shunt, and artificial liver support systems have a very limited role in improving outcomes in HRS. Liver transplantation remains the definitive treatment for HRS. The frequency of simultaneous liver-kidney transplantation has increased dramatically in the Model for End-stage Liver Disease era, with changes in organ allocation policies. This has resulted in a more urgent need to predict native kidney recovery from HRS after liver transplantation alone, to avoid unnecessary simultaneous liver-kidney transplantation.

Prognosis of Patients with Cirrhosis and AKI Who Initiate RRT

BACKGROUND AND OBJECTIVES

Literature on the prognosis of patients with cirrhosis who require RRT for AKI is sparse and is confounded by liver transplant eligibility. An update on outcomes in the nonlisted subgroup is needed. Our objective was to compare outcomes in this group between those diagnosed with hepatorenal syndrome and acute tubular necrosis, stratifying by liver transplant listing status.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Retrospective cohort study of patients with cirrhosis acutely initiated on hemodialysis or continuous RRT at five hospitals, including one liver transplant center. Multivariable regression and survival analysis were performed.

RESULTS

Four hundred seventy-two subjects were analyzed (341 not listed and 131 listed for liver transplant). Among nonlisted subjects, 15% (51 of 341) were alive at 6 months after initiating RRT. Median survival was 21 (interquartile range [IQR], 8, 70) days for those diagnosed with hepatorenal syndrome and 12 (IQR, 3, 43) days for those diagnosed with acute tubular necrosis (P=0.25). Among listed subjects, 48% (63 of 131) received a liver transplant. Median transplant-free survival was 15 (IQR, 5, 37) days for those diagnosed with hepatorenal syndrome and 14 (IQR, 4, 31) days for those diagnosed with acute tubular necrosis (P=0.60). When stratified by transplant listing, with adjusted Cox models we did not detect a difference in the risk of death between hepatorenal syndrome and acute tubular necrosis (hazard ratio [HR], 0.81; 95% confidence interval [95% CI], 0.59 to 1.11, among those not listed; HR, 0.73; 95% CI, 0.44 to 1.19, among those listed).

CONCLUSIONS

Cause of AKI was not significantly associated with mortality in patients with cirrhosis who required RRT. Among those not listed for liver transplant, mortality rates were extremely high in patients both with hepatorenal syndrome and acute tubular necrosis.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2017_11_09_CJASNPodcast_18_1_A.mp3.

Fluctuations of Estimated Glomerular Filtration Rate Outside Kidney Disease Improving Global Outcomes Diagnostic Criteria for Acute Kidney Injury in End-Stage Liver Disease Outpatients and Outcome Postliver Transplantation

BACKGROUND

Renal dysfunction in end-stage liver disease (ESLD) results from systemic conditions that affect both liver and kidney with activation of vasoconstrictor systems. In this setting, estimated glomerular filtration rate (eGFR) may undergo variations often outside Kidney Disease Improving Global Outcomes criteria for acute kidney injury (AKI) diagnosis, whose meaning is not clear. The aim of this study was to evaluate eGFR variations in ESLD outpatients listed for liver transplant (liver Tx) and the association with post-Tx outcome.

METHODS

Fifty-one patients with ESLD were retrospectively evaluated from listing to transplant (L-Tx time), intraoperatively (Tx time), and up to 5 years post-Tx time. Variations between the highest and the lowest eGFR occurring in more than 48 hours, not satisfying Kidney Disease Improving Global Outcomes guideline, were considered as fluctuations (eGFR-F). Fluctuations of eGFR greater than 50% were defined as eGFR drops (DeGFR). Early graft dysfunction, AKI within 7 days, chronic kidney disease, and short- and long-term patient survivals were considered as outcomes.

RESULTS

All patients presented eGFR-F, whereas DeGFR were observed in 18 (35.3%) of 51 (DeGFR+ group). These patients presented higher levels of Model for End-stage Liver Disease score, pre-Tx bilirubin and significantly greater incidence of post-Tx AKI stages 2 to 3 compared with patients without drops (DeGFR-). DeGFR was the only independent predictive factor of the occurrence of post-Tx AKI. The occurrence of AKI post-Tx was associated with the development of chronic kidney disease at 3 months and 5 years post-Tx.

CONCLUSIONS

Drops of eGFR are more frequently observed in patients with a worse degree of ESLD and are associated with a worse post-Tx kidney outcome.

Prevalence of chronic kidney disease in patients with chronic hepatitis B: A cross-sectional survey

Renal safety is a major concern during long-term antiviral treatment for chronic hepatitis B (CHB). This study aimed to investigate the prevalence of chronic kidney disease (CKD) in patients with CHB that had been treated with antiviral therapy. This was a single-centre, cross-sectional study in a real-life cohort in which all patients received antiviral treatment. Serum creatinine-based equations from the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) were used to estimate the glomerular filtration rate (GFR). CKD was defined as an eGFR <60 mL/min/1.73 m² or a urinary albumin to creatinine ratio ≥ 3 mg/mmol (defined as albuminuria). Univariate and multivariate analyses were conducted to determine the risk factors of CKD. A total of 1985 patients were included in the analysis from February 2015 to December 2015. The mean age and median duration of antiviral treatment was 42.20 years and 17.05 months, respectively. The overall prevalence of CKD was 7.9% (157/1985), with 44 patients experiencing decreased renal function (eGFR less than 60 mL/min/1.73 m²) and 129 patients with albuminuria. Patients with cirrhosis had a higher prevalence of a decreased GFR (4.3% vs 1.6%, P<.001) and albuminuria (11.1% vs 5.2%, P<.001) than those without cirrhosis. In the multivariate analysis, hypertension (Odds Ratio [OR] 4.564, P<.001), diabetes mellitus (OR 2.688, P<.001) and cirrhosis (OR 1.918, P<.001) were independent factors associated with the presence of CKD. CKD was a clinically significant comorbidity in patients with CHB. Special attention should be paid to cirrhotic patients and patients with the metabolic syndrome.

Acute kidney injury in acute-on-chronic liver failure: where does hepatorenal syndrome fit?

Renal dysfunction occurs in 25% to 50% of patients with cirrhosis admitted to the hospital with an acute episode of hepatic decompensation and may be due to underlying chronic kidney disease, an acute deterioration, or both. An acute deterioration in renal function in cirrhotic patients is now collectively referred to as acute kidney injury (AKI), which has been subclassified into different grades of severity that identify prognostic groups. Acute-on-chronic liver failure is characterized by acute hepatic and/or extrahepatic organ failure driven by a dysregulated immune response and systemic inflammatory response. AKI is also one of the defining features of ACLF and a major component in grading the severity of acute-on-chronic liver failure. As such, the pattern of AKI now observed in patients admitted to the hospital with acutely decompensated liver disease is likely to be one of inflammatory kidney injury including acute tubular injury (referred in this review as non-hepatorenal syndrome [HRS]-AKI) rather than HRS. As the management and supportive treatment of non-HRS-AKI potentially differ from those of HRS, then from the nephrology perspective, it is important to distinguish between non-HRS-AKI and HRS-AKI when reviewing patients with acute-on-chronic liver failure and AKI, so that appropriate and early management can be instituted.

Remodeling the model for end-stage liver disease for predicting mortality risk in critically ill patients with cirrhosis and acute kidney injury

Serum creatinine measurement demonstrates a poor specificity and sensitivity for the early diagnosis of acute kidney injury (AKI) in patients with cirrhosis. The existing model for end‐stage liver disease (MELD) score reveals multiple pitfalls in critically ill patients with cirrhosis and acute kidney injury (CAKI). The aim of this study was to re‐evaluate the role of creatinine values in the existing MELD score and to develop a novel score for CAKI, named the “acute kidney injury–model for end‐stage liver disease score” (AKI‐MELD score). We extracted 651 CAKI from the Multiparameter Intelligent Monitoring in Intensive Care database. A time‐dependent Cox regression analysis was performed for developing remodeled MELD scores (Reweight‐MELD score, Del‐Cr‐MELD score, and AKI‐MELD score). The area under the receiver operating characteristic curve provided the discriminative power of scoring models related to outcome. The hazard ratio of creatinine was 1.104 (95% confidence interval [CI], 0.945‐1.290; P = 0.211). Reweight‐MELD score and Del‐Cr‐MELD score (decreasing the weight of creatinine) were superior to the original MELD score (all P < 0.001). The new AKI‐MELD score consists of bilirubin, the international normalized ratio, and the ratio of creatinine in 48 hours to creatinine at admission. It had competitive discriminative ability for predicting mortality (area under the receiver operating characteristic curve, 0.720 [95% CI, 0.653‐0.762] at 30 days, 0.688 [95% CI, 0.630‐0.742] at 90 days, and 0.671 [95% CI, 0.612‐0.725] at 1 year). Further, AKI‐MELD score had significantly higher predictive ability in comparison with MELD score, MELD‐Na score, and Updated MELD score (all P < 0.001). Conclusion: The predictive value of creatinine for CAKI should be re‐evaluated. AKI‐MELD score is a potentially reliable tool to determine the prognosis for mortality of CAKI. (Hepatology Communications 2017;1:748–756)

Risk Factors and Outcomes of Acute Kidney Injury in Patients With Hepatitis B Virus-Related Acute-on-Chronic Liver Failure

BACKGROUND

Acute kidney injury (AKI) is common in patients with hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF); however, few studies concerning the risk factors and recovery patterns of renal function have been published.

MATERIALS AND METHODS

A retrospective analysis of 150 patients with HBV-ACLF was performed. The occurrence, risk factors and functional recovery of AKI among patients with HBV-ACLF were investigated.

RESULTS

A total of 90 patients (60%) with HBV-ACLF developed AKI. Patients with AKI had higher creatine kinase (P = 0.004), total bilirubin (P = 0.039), HBV viral load (P = 0.044), serum creatine (P < 0.001) and model for end-stage liver disease (MELD) score (P < 0.001) values and a higher proportion of hepatic encephalopathy (P = 0.032) and spontaneous bacterial peritonitis (SBP) (P = 0.042) than patients without AKI. Logistic regression analysis illustrated that SBP (odds ratio = 6.214, P = 0.012) and MELD score (odds ratio = 1.097, P = 0.006) were risk factors for the development of AKI. A subgroup analysis of recovery patterns in renal function showed that patients with a severe AKI stage had worse outcomes (P = 0.007). The proportion of patients who experienced a complete recovery was higher in survivors than in the overall AKI populations (P = 0.004). Follow-up studies showed that the no-AKI group had a higher transplant-free survival rate than the AKI group at day 90 (80.0% versus 26.7%, respectively, P < 0.001). The survival rate among patients with AKI Stage 1 was higher than that of patients with AKI Stage 2 and patients with AKI Stage 3 (P < 0.001).

CONCLUSIONS

AKI is common in patients with HBV-ACLF. The SBP and MELD score have some prognosis value for patients with AKI. AKI and its stages affect the 90-day transplant-free mortality rate. It is important to focus on exploring the early recognition of AKI and early intervention of those risk factors in individuals with HBV-ACLF.

Comparison of creatinine and cystatin formulae with 51 Chromium-ethylenediaminetetraacetic acid glomerular filtration rate in patients with decompensated cirrhosis

BACKGROUND AND AIM

Evaluation of renal function, that is, glomerular filtration rate (GFR), has become very important, but conventional mathematical formulae for GFR assessment are inaccurate in patients with cirrhosis. The aim of the present study was to compare serum creatinine (sCr)-based and serum cystatin C (cysC)-based estimated GFR (eGFR) formulae with ⁵¹ Chromium-ethylenediaminetetraacetic acid GFR (⁵¹ Chr-GFR) in patients with stable decompensated cirrhosis.

METHODS

In 129 Caucasian patients with decompensated cirrhosis, we assessed sCr-based GFRs [Modification of Diet in Renal Disease and chronic kidney disease-epidemiology (CKD-EPI)-sCr formulae], cysC-based GFRs [Hoek, Larsson, and CKD-EPI-cysC equations], and the mathematical formulae, which combined both sCr and cysC [i.e. CKD-EPI-sCr-cysC and the specific for cirrhotics formula recently proposed by Mindikoglu et al. (Mindikoglu-eGFR)]. Multivariate linear regression analysis was used for GFR predictors in our cohort.

RESULTS

The correlations between ⁵¹ Chr-GFR and all mathematical formulae were good (Spearman r²  > 0.68, P < 0.001). Modification of Diet in Renal Disease and CKD-EPI-sCr had lower bias (6.6 and -4.8, respectively), compared with the other eGFRs, while Mindikoglu-eGFR and CKD-EPI-sCr-cysC formulae had greater precision (17.1 and 17.3, respectively), compared with the other eGFRs. CKD-EPI-sCr and Mindikoglu-eGFR had higher accuracy (39% and 41%, respectively), compared with the other eGFRs. The factors independently associated with the ⁵¹ Chr-GFR were age, cysC, and sCr, and the new derived formula had lower bias (0.89) and similar precision (17.2) and accuracy (41%) with Mindikoglu-eGFR formula.

CONCLUSION

The specific mathematical formulae derived from patients with cirrhosis seem to provide superior assessment of renal function, compared with the conventional used sCr-based and cysC-based formulae.

[Acute Kidney Injury in Cirrhotic Patients with Portal Hypertension]

Acute kidney injury (AKI) is one of the most common manifestations encountered in clinical practice. It is associated with high morbidity and mortality in cirrhotic pre- and post-transplantation patients. Hepatorenal syndrome (HRS), a special form of AKI in cirrhotic patients, was recognized as a consequence of renal vasoconstriction from systemic/renal hemodynamic alterations developed in advanced cirrhosis with portal hypertension. Recently, multiple factors-such as infection/inflammation, underlying glomerulonephritis, bile cast, or increased abdominal pressure-have been considered to contribute to renal dysfunction in cirrhotic patients, which were presumed to induce HRS. Moreover, in addition to changing the definition of AKI in the nephrologic guidelines, the new AKI definition for early diagnosis and intervention based on characteristics of liver cirrhosis has been proposed in an international meeting. This article provides a comprehensive and recent review of AKI definition, laying out the topics in accordance with the pathophysiologic mechanisms and therapeutic interventions of AKI in cirrhotic patients with portal hypertension.

Predictors of Mortality in the Critically Ill Cirrhotic Patient: Is the Model for End-Stage Liver Disease Enough?

BACKGROUND

Critically ill cirrhotics require liver transplantation urgently, but are at high risk for perioperative mortality. The Model for End-stage Liver Disease (MELD) score, recently updated to incorporate serum sodium, estimates survival probability in patients with cirrhosis, but needs additional evaluation in the critically ill. The purpose of this study was to evaluate the predictive power of ICU admission MELD scores and identify clinical risk factors associated with increased mortality.

STUDY DESIGN

This was a retrospective review of cirrhotic patients admitted to the ICU between January 2011 and December 2014. Patients who were discharged or underwent transplantation (survivors) were compared with those who died (nonsurvivors). Demographic characteristics, admission MELD scores, and clinical risk factors were recorded. Multivariate regression was used to identify independent predictors of mortality, and measures of model performance were assessed to determine predictive accuracy.

RESULTS

Of 276 patients who met inclusion criteria, 153 were considered survivors and 123 were nonsurvivors. Survivor and nonsurvivor cohorts had similar demographic characteristics. Nonsurvivors had increased MELD, gastrointestinal bleeding, infection, mechanical ventilation, encephalopathy, vasopressors, dialysis, renal replacement therapy, requirement of blood products, and ICU length of stay. The MELD demonstrated low predictive power (c-statistic 0.73). Multivariate analysis identified MELD score (adjusted odds ratio [AOR] = 1.05), mechanical ventilation (AOR = 4.55), vasopressors (AOR = 3.87), and continuous renal replacement therapy (AOR = 2.43) as independent predictors of mortality, with stronger predictive accuracy (c-statistic 0.87).

CONCLUSIONS

The MELD demonstrated relatively poor predictive accuracy in critically ill patients with cirrhosis and might not be the best indicator for prognosis in the ICU population. Prognostic accuracy is significantly improved when variables indicating organ support (mechanical ventilation, vasopressors, and continuous renal replacement therapy) are included in the model.

Acute kidney injury and post-reperfusion syndrome in liver transplantation

In the past decades liver transplantation (LT) has become the treatment of choice for patients with end stage liver disease (ESLD). The chronic shortage of cadaveric organs for transplantation led to the utilization of a greater number of marginal donors such as older donors or donors after circulatory death (DCD). The improved survival of transplanted patients has increased the frequency of long-term complications, in particular chronic kidney disease (CKD). Acute kidney injury (AKI) post-LT has been recently recognized as an important risk factor for the occurrence of de novo CKD in the long-term outcome. The onset of AKI post-LT is multifactorial, with pre-LT risk factors involved, including higher Model for End-stage Liver Disease score, more sever ESLD and pre-existing renal dysfunction, either with intra-operative conditions, in particular ischaemia reperfusion injury responsible for post-reperfusion syndrome (PRS) that can influence recipient’s morbidity and mortality. Post-reperfusion syndrome-induced AKI is an important complication post-LT that characterizes kidney involvement caused by PRS with mechanisms not clearly understood and implication on graft and patient survival. Since pre-LT risk factors may influence intra-operative events responsible for PRS-induced AKI, we aim to consider all the relevant aspects involved in PRS-induced AKI in the setting of LT and to identify all studies that better clarified the specific mechanisms linking PRS and AKI. A PubMed search was conducted using the terms liver transplantation AND acute kidney injury; liver transplantation AND post-reperfusion syndrome; acute kidney injury AND post-reperfusion syndrome; acute kidney injury AND DCD AND liver transplantation. Five hundred seventy four articles were retrieved on PubMed search. Results were limited to title/abstract of English-language articles published between 2000 and 2015. Twenty-three studies were identified that specifically evaluated incidence, risk factors and outcome for patients developing PRS-induced AKI in liver transplantation. In order to identify intra-operative risk factors/mechanisms specifically involved in PRS-induced AKI, avoiding confounding factors, we have limited our study to “acute kidney injury AND DCD AND liver transplantation”. Accordingly, three out of five studies were selected for our purpose.

Prognosis of cirrhotic patients admitted to the general ICU

BACKGROUND

The prognosis of cirrhotic patients admitted to the ICU is considered to be poor but has been mainly reported in liver ICU. We aimed to describe the prognosis of cirrhotic patients admitted to a general ICU, to assess the predictors of mortality in this population, and, finally, to identify a subgroup of patients in whom intensive care escalation might be discussed.

RESULTS

We performed a retrospective monocentric study of all cirrhotic patients consecutively admitted between 2002 and 2014 in a general ICU in a regional university hospital. Two hundred and eighteen cirrhotic patients were admitted to the ICU. The 28-day and 6-month mortality rates were 53 and 74 %, respectively. Among the 115 patients who were discharged from ICU, only eight patients underwent liver transplantation, whereas 48 had no clear contraindication. Multivariable analyses on 28-day mortality identified three independent variables, incorporated into a new three-variable prognostic model as follows: SOFA ≥ 12 (OR 4.2 [2.2-8.0]; 2 points), INR ≥ 2.6 (OR 2.5 [1.3-4.8]; 1 point), and renal replacement therapy (OR 2.3 [1.1-5.1]; 1 point). For a value of the score at 4 (16 % of patients), 28-day and 3-month mortality rates were 91 and 100 %, respectively. An external validation of the score among 149 critically ill cirrhotic patients showed a good accuracy for predicting in-ICU mortality.

CONCLUSIONS

Mortality of cirrhotic patients admitted to a general ICU was comparable to that of other studies. A pragmatic score integrating the SOFA score, INR, and the need for extrarenal epuration was strongly associated with mortality. Among the 16 % of patients presenting with score 4 at ICU admission, 100 % died in the 3-month follow-up period. The prognostic evaluation on day 3 remains essential for the majority of patients. However, this score calculable at ICU admission might identify patients in whom the benefit of intensive care escalation should be discussed, in particular when liver transplantation is contraindicated.

The Effect of Renal Function Impairment on the Mortality of Cirrhotic Patients: A Nationwide Population-Based 3-Year Follow-up Study

Renal function impairment (RFI) contributes to poor prognosis in cirrhotic patients. However, there have been no studies that seek to identify the effect of different types of RFI on the mortality of cirrhotic patients. We used the National Health Insurance Database, derived from the Taiwan National Health Insurance Program, to identify 44365 cirrhotic patients between January 1, 2007 and December 31, 2007. RFI was identified in 2832 cirrhotic patients, including 1075 with acute renal failure (ARF) (169 with hepatorenal syndrome, HRS; 906 with non-hepatorenal syndrome, NHRS), 705 with chronic kidney disease (CKD), and 1052 with end stage renal disease (ESRD). After Cox proportional hazard regression analysis adjusted by gender, age, and comorbid disorders, the 30-day, 30 to 90-day, 90-day to 1-year, and 1 to 3-year mortality hazard ratios (HR) compared to the non-RFI group were: (ARF) 5.19 (4.70-5.74), 3.23 (2.76-3.77), 1.51 (1.26-1.81), and 1.35 (1.13-1.61), respectively; (CKD) 2.70 (2.30-3.18), 2.03 (1.66-2.49), 1.60 (1.34-1.90), and 1.26 (1.06-1.49), respectively; and (ESRD) 1.42 (1.17-1.72), 1.62 (1.35-1.94), 1.90 (1.68-2.15), and 1.67 (1.48-1.89), respectively. Compared to NHRS, the 30-day, 30 to 90-day, 90-day to 1-year, and 1 to 3-year mortality HRs of HRS were 1.03 (0.80-1.32), 2.13 (1.46-3.11), 1.58 (0.90-2.75), and 2.51 (1.41-4.48), respectively, in cirrhotic patients with ARF. These results indicate the effects of CKD and ESRD on the mortality of cirrhotic patients are distributed equally in every survival stage, whereas the effect of ARF appears only in the early stage. Compared to NHRS, HRS contributes to a higher mortality risk at the late survival stage.

Therapeutic alternatives for the treatment of type 1 hepatorenal syndrome: A Delphi technique-based consensus

AIM

To propose several alternatives treatment of type 1 hepatorenal syndrome (HRS-1) what is the most severe expression of circulatory dysfunction on patients with portal hypertension.

METHODS

A group of eleven gastroenterologists and nephrologists performed a structured analysis of available literature. Each expert was designated to review and answer a question. They generated draft statements for evaluation by all the experts. Additional input was obtained from medical community. In order to reach consensus, a modified three-round Delphi technique method was used. According to United States Preventive Services Task Force criteria, the quality of the evidence and level of recommendation supporting each statement was graded.

RESULTS

Nine questions were formulated. The available evidence was evaluated considering its quality, number of patients included in the studies and the consistency of its results. The generated questions were answered by the expert panel with a high level of agreement. Thus, a therapeutic algorithm was generated. The role of terlipressin and norepinephrine was confirmed as the pharmacologic treatment of choice. On the other hand the use of the combination of octreotide, midodrine and albumin without vasoconstrictors was discouraged. The role of several other options was also evaluated and the available evidence was explored and discussed. Liver transplantation is considered the definitive treatment for HRS-1. The present consensus is an important effort that intends to organize the available strategies based on the available evidence in the literature, the quality of the evidence and the benefits, adverse effects and availability of the therapeutic tools described.

CONCLUSION

Based on the available evidence the expert panel was able to discriminate the most appropriate therapeutic alternatives for the treatment of HRS-1.

Intensive care management of patients with liver disease: proceedings of a single-topic conference sponsored by the Brazilian Society of Hepatology

Survival rates of critically ill patients with liver disease has sharply increased in recent years due to several improvements in the management of decompensated cirrhosis and acute liver failure. This is ascribed to the incorporation of evidence-based strategies from clinical trials aiming to reduce mortality. In order to discuss the cutting-edge evidence regarding critical care of patients with liver disease, a joint single topic conference was recently sponsored by the Brazilian Society of Hepatology in cooperation with the Brazilian Society of Intensive Care Medicine and the Brazilian Association for Organ Transplantation. This paper summarizes the proceedings of the aforementioned meeting and it is intended to guide intensive care physicians, gastroenterologists and hepatologists in the care management of patients with liver disease.

[Hepatorenal syndrome in decompensated cirrhosis : A special form of acute renal failure]

Renal failure is a serious complication in patients with advanced cirrhosis. It occurs in about 20 % of patients hospitalized with cirrhosis. In about 70 % it is caused by prerenal failure, and in 30 % it is due to intrarenal causes. In about 70 % of patients with rperenal failure, renal function can be restored with fluid replacement, but the remaining 30 % are unresponsive to volume expansion. Minor increase in serum creatinine have been shown to be clinically relevant and can adversely affect survival. Therefore early efforts should be made to avoid precipitation of renal failure.Hepatorenal syndrome (HRS) is a  fully reversible impairment of renal function in patients with cirrhosis unresponsive to volume expansion characterized by an acute progressive decrease in kidney function (serumcreatinin > 1,5 mg/dl) - type 1 HRS, whereas type 2 HRS features a decrease in kidney function over a long time, mostly in patients with refractory ascites. Therapy with vasoconstrictors like terlipressin to reverse splanchnic vasodilation, together with albumin is effective in 30-50 % of patients with HRS 1 and improves survival. The only effective longterm therapy is livertransplantation. An improvement of kidney fuction before transplantation is associated with a better outcome and posttransplant kidney function.

Changes in Kidney Function After Transjugular Intrahepatic Portosystemic Shunts Versus Large-Volume Paracentesis in Cirrhosis: A Matched Cohort Analysis

BACKGROUND

Patients with cirrhosis and refractory ascites have physiologic and hormonal dysregulation that contributes to decreased kidney function. Placement of a transjugular intrahepatic portosystemic shunt (TIPS) can reverse these changes and potentially improve kidney function. We sought to evaluate change in estimated glomerular filtration rate (eGFR) following TIPS placement.

STUDY DESIGN

Retrospective, matched cohort analysis.

SETTINGS & PARTICIPANTS

Patients who underwent first-time TIPS placement for refractory ascites in 1995 to 2014. Frequency matching was used to generate a comparator group of patients with cirrhosis and ascites treated with serial large-volume paracentesis (LVP) in a 1:1 fashion.

PREDICTOR

TIPS placement compared to serial LVP.

OUTCOME

Change in eGFR over 90 days' follow-up.

MEASUREMENTS

Multivariable regression stratified by baseline eGFR<60 versus ≥60mL/min/1.73m(2); analysis of effect modification between TIPS placement and baseline eGFR.

RESULTS

276 participants (TIPS, n=138; serial LVP, n=138) were analyzed. After 90 days, eGFRs increased significantly after TIPS placement in participants with baseline eGFRs<60mL/min/1.73m(2) compared to treatment with serial LVP (21 [95% CI, 13-29] mL/min/1.73m(2); P<0.001) and was no different in those with eGFRs≥60mL/min/1.73m(2) (1 [95% CI, -9 to 12] mL/min/1.73m(2); P=0.8). There was significant effect modification between TIPS status and baseline eGFR (P=0.001) in a model that included all participants.

LIMITATIONS

Outcomes restricted by clinically recorded data; clinically important differences may still exist between the TIPS and LVP cohorts despite good statistical matching.

CONCLUSIONS

TIPS placement was associated with significant improvement in kidney function. This was most prominent in participants with baseline eGFRs<60mL/min/1.73m(2). Prospective studies of TIPS use in populations with eGFRs<60mL/min/1.73m(2) are needed to evaluate these findings.

National trends of acute kidney injury requiring dialysis in decompensated cirrhosis hospitalizations in the United States

BACKGROUND AND AIMS

Cirrhosis affects 5.5 million patients with estimated costs of US$4 billion. Previous studies about dialysis requiring acute kidney injury (AKI-D) in decompensated cirrhosis (DC) are from a single center/year. We aimed to describe national trends of incidence and impact of AKI-D in DC hospitalizations.

METHODS

We extracted our cohort from the Nationwide Inpatient Sample (NIS) from 2006-2012. We identified hospitalizations with DC and AKI-D by validated ICD9 codes. We analyzed temporal changes in DC hospitalizations complicated by AKI-D and utilized multivariable logistic regression models to estimate AKI-D impact on hospital mortality.

RESULTS

We identified a total of 3,655,700 adult DC hospitalizations from 2006 to 2012 of which 78,015 (2.1 %) had AKI-D. The proportion with AKI-D increased from 1.5 % in 2006 to 2.23 % in 2012; it was stable between 2009 and 2012 despite an increase in absolute numbers from 6773 to 13,930. The overall hospital mortality was significantly higher in hospitalizations with AKI-D versus those without (40.87 vs. 6.96 %; p < 0.001). In an adjusted multivariable analysis, adjusted odds ratio for mortality was 2.17 (95 % CI 2.06-2.28; p < 0.01) with AKI-D, which was stable from 2006 to 2012. Changes in demographics and increases in acute/chronic comorbidities and procedures explained temporal changes in AKI-D.

CONCLUSIONS

Proportion of DC hospitalizations with AKI-D increased from 2006 to 2009, and although this was stable from 2009 to 2012, there was an increase in absolute cases. These results elucidate the burden of AKI-D on DC hospitalizations and excess associated mortality, as well as highlight the importance of prevention, early diagnosis and testing of novel interventions in this vulnerable population.

Impact of acute kidney injury on prognosis of patients with liver cirrhosis and ascites: A retrospective cohort study

BACKGROUND AND AIM

Acute kidney injury (AKI) is a common complication in patients with liver cirrhosis, and its impact on the clinical course is increasingly recognized. Diagnostic classification systems for AKI in cirrhosis have been suggested. The prognostic significance of the respective AKI stages remains to be evaluated in decompensated cirrhosis with ascites.

METHODS

Data of consecutive patients with cirrhosis and ascites undergoing paracentesis at a tertiary care center were analyzed. AKI was defined as an increase in serum creatinine of ≥ 0.3 mg/dL or by ≥ 50% within 7 days after paracentesis, and classified according to (i) revised Acute Kidney Injury Network (AKIN) criteria and (ii) modified AKI criteria for cirrhosis (C-AKI). In contrast to AKIN, C-AKI stage A discriminates prognosis based on an absolute creatinine cut-off at < 1.5 mg/dL versus C-AKI stage B at ≥ 1.5 mg/dL.

RESULTS

The final study cohort included 239 patients. Median transplant-free survival was 768 days (95% confidence interval [CI]: 331-1205 days) without AKI, 198 (0-446) in AKI-1, 91 (0-225) in AKI-2, 19 (0-40) and in AKI-3, whereas it was 89 (20-158) days in C-AKI-A, 384 (0-1063) in C-AKI-B, and 22 (7-776) in C-AKI-C. Mild AKI was already associated with significantly increased 30-day mortality (AKI-1:26.4%, C-AKI-A:33.3%) as compared with patients without AKI (14.3%), even when serum creatinine remained within normal range (< 1.2 mg/dL) we observed a significant 30-day mortality.

CONCLUSION

AKIN criteria-considering small increases in serum creatinine rather than absolute thresholds-seem to be more accurate for estimating prognosis of AKI after paracentesis than C-AKI criteria. Even patients developing AKI-1 with "normal" serum creatinine are at increased risk for mortality.

Renal failure in cirrhosis: Emerging concepts

Acute renal failure, now termed acute kidney injury (AKI), is frequently found in patients with cirrhosis. The occurrence of AKI, irrespective of the underlying cause, is associated with reduced in-hospital, 3-mo and 1-year survival. Hepatorenal syndrome is associated with the worst outcome among AKI patients with cirrhosis. Several definitions for AKI that have been proposed are outlined and evaluated in this paper. Among these, the International Club for Ascites-AKI criteria substantially strengthen the quality of early diagnosis and intervention according to underlying cause of AKI.

Acute Kidney Injury in Liver Disease: Role of Biomarkers

Acute kidney injury (AKI) is a common complication in patients with advanced cirrhosis and is associated with significant mortality. The most common etiologies of AKI in this setting are prerenal azotemia, acute tubular necrosis, and hepatorenal syndrome. Despite the overall poor outcomes of patients with cirrhosis and AKI, potentially efficacious therapies exist but must be tailored to the specific AKI etiology. Unfortunately, determining the etiology of AKI in the setting of cirrhosis is notoriously difficult. Many of the standard diagnostic tools, such as urine microscopy and the fractional excretion of sodium, have traditionally been ineffective. Novel biomarkers of kidney tubular injury may be able to assist with differential diagnosis and the appropriate targeting of treatments by distinguishing structural from functional causes of AKI. In recent studies, both urinary neutrophil gelatinase-associated lipocalin and interleukin-18 have shown the ability to distinguish hepatorenal syndrome from prerenal azotemia and acute tubular necrosis. In addition, multiple biomarkers, including neutrophil gelatinase-associated lipocalin and interleukin-18, have demonstrated the ability to independently predict both progression of AKI and mortality. Critically, recent research also indicated that commonly available tests, fractional excretion of sodium and proteinuria, may also be able to distinguish etiologies of AKI in cirrhosis, but diagnostic cutoffs must be re-conceptualized specifically to this unique AKI setting.

Prognosis of Acute Kidney Injury and Hepatorenal Syndrome in Patients with Cirrhosis: A Prospective Cohort Study

Background/Aims. Acute kidney injury is a common problem for patients with cirrhosis and is associated with poor survival. We aimed to examine the association between type of acute kidney injury and 90-day mortality. Methods. Prospective cohort study at a major US liver transplant center. A nephrologist's review of the urinary sediment was used in conjunction with the 2007 Ascites Club Criteria to stratify acute kidney injury into four groups: prerenal azotemia, hepatorenal syndrome, acute tubular necrosis, or other. Results. 120 participants with cirrhosis and acute kidney injury were analyzed. Ninety-day mortality was 14/40 (35%) with prerenal azotemia, 20/35 (57%) with hepatorenal syndrome, 21/36 (58%) with acute tubular necrosis, and 1/9 (11%) with other (p = 0.04 overall). Mortality was the same in hepatorenal syndrome compared to acute tubular necrosis (p = 0.99). Mortality was lower in prerenal azotemia compared to hepatorenal syndrome (p = 0.05) and acute tubular necrosis (p = 0.04). Ten participants (22%) were reclassified from hepatorenal syndrome to acute tubular necrosis because of granular casts on urinary sediment. Conclusions. Hepatorenal syndrome and acute tubular necrosis result in similar 90-day mortality. Review of urinary sediment may add important diagnostic information to this population. Multicenter studies are needed to validate these findings and better guide management.

Appraising cardiac dysfunction in liver transplantation: an ongoing challenge

End-stage liver disease (ESLD) is a multisystemic disease that adversely and mutually aggravates other organs such as the heart. Cardiac dysfunction in ESLD encompasses a spectrum of disease that could be aggravated, precipitated or be occurring hand-in-hand with coexisting aetiological factors precipitating cirrhosis. Additionally and more complexly, liver transplantation, the curative modality of ESLD, is responsible for additional intra- and postoperative short- and long-term cardiac morbidity. The phenotypic distinction of the different forms of cardiac dysfunction in ESLD albeit important prognostically and therapeutically is not allowed by the current societal recommendations, due to conceptual, and methodological limitations in the appraisal of cardiac function and structure in ESLD and in designing studies that are based on this appraisal. This review comprehensively discusses the spectrum of cardiac dysfunction in ESLD, discusses the limitations of the current appraisal of cardiac dysfunction in ESLD, and proposes a hypothetical approach for studying cardiac dysfunction in liver transplant candidates.

Renal replacement therapy in the ICU: comparison of clinical features and outcomes of patients with acute kidney injury and dialysis-dependent end-stage renal disease

BACKGROUND

The goal of this study is to study clinical features and outcomes of the patients who had renal replacement therapy (RRT) in the intensive care unit (ICU) between 2000 and 2007.

METHODS

We retrospectively studied 222 patients.

RESULTS

Overall ICU mortality and invasive mechanical ventilation (IMV) rates were 58.1 and 61.3 %. The mean APACHE II score was 27.6 ± 8.3. Chronic dialysis (CD) patients formed 45.5 % of the study population. Acute kidney injury (AKI) patients had higher rates of IMV (73 vs. 51.5 %, p = 0.002), cancer (27.8 vs. 7.9 %, p ≤ 0.001) and mortality (67.8 vs. 50.5 %, p = 0.010) than CD patients. AKI patients with normal kidney function (NKF) before ICU admission had poorer prognosis than acute-on-chronic kidney disease (CKD) and CD patients (78.6, 51 and 50.5 %, respectively, p ≤ 0.001). Multivariate analysis showed that IMV (OR, 14.8; 95 % CI, 5.47-40.05; p ≤ 0.001) and having NKF before hospitalization (OR, 2.8; 95 % CI, 1.04-7.37; p = 0.041) were predictors of overall ICU mortality. Additionally, IMV is found as a prognostic factor for both AKI (OR, 18.7; 95 % CI, 4.48-77.72; p ≤ 0.001) and CD patients (OR, 8.14; 95 % CI, 2.01-33.04; p = 0.003), but APACHE II score is meaningful only for CD patients (OR, 1.13; 95 % CI, 1.02-1.26; p = 0.024). The areas under the ROC curves for APACHE II score were 0.52 (95 % CI, 0.39-0.66) for AKI and 0.78 (95 % CI, 0.55-0.89) for CD patients.

CONCLUSION

The observed ICU mortality among patients requiring RRT is high and IMV is associated with mortality. AKI patients have increased mortality compared to CD patients. AKI patients with past NKF have poorer prognosis than acute-on-CKD and CD patients.

No sustained impact of intermittent extracorporeal liver support on thrombocyte time course in a randomized controlled albumin dialysis trial

Reduction of platelets is a common finding in patients with liver disease and can be aggravated by extracorporeal therapies, e.g. artificial liver support. The impact of extracorporeal albumin dialysis on the time count and time course of platelets in liver failure patients was evaluated in a randomized controlled clinical trial. Mean thrombocyte reduction during a single extracorporeal liver support therapy was -15.1% [95%CI: -17.7; -12.5]. No differences were found between treatments of patients with a more reduced platelet count (<100 GPT/L: -15.6% [-19.5; -11.7%]; n = 43) compared to patients with normal or slightly decreased thrombocytes (-14.6% [-18.3%; -11.0%]; n = 43; P = 0.719). The variation of platelet count within 24 h after onset of extracorporeal therapy treatment was less, albeit significant (-3.5% [-6.3%; -0.7%], P < 0.016). Absolute thrombocyte variability was comparable between both groups (with extracorporeal therapy -5.6 GPT/L [-9.7; -1.4], without extracorporeal therapy -1.3 GPT/L [-7.3; 4.7]; P = 0.243), whereas relative decrease of thrombocytes within a 24-h period of extracorporeal therapy was greater than the changes in patients without extracorporeal therapy (-3.5% [-6.3%; -0.7%] vs. 2.0% [-2.0%; 5.9%]; P = 0.026]. Within a period of two weeks after enrollment, no significant differences of platelet count were observed either between the two groups or in the time course (P(group) = 0.337, P(time) = 0.277). Reduction of platelets during intermittent extracorporeal liver support was less pronounced within a 24-h period as before and after a single treatment and was comparable to variations in the control group without extracorporeal therapy.

Role of cardiovascular intervention as a bridge to liver transplantation

End stage liver disease (ESLD) is associated with many specific derangements in cardiovascular physiology, which influence perioperative outcomes and may profoundly influence diagnostic and management strategies in the preoperative period. This review focuses on evidence-based diagnosis and management of coronary, hemodynamic and pulmonary vascular disease in this population with an emphasis on specific strategies that may provide a bridge to transplantation. Specifically, we address the underlying prevalence of cardiovascular disease states in the ESLD population, and relevant diagnostic criteria thereof. We highlight traditional and non-traditional predictors of cardiovascular outcomes following liver transplant, as well as data to guide risk-factor based diagnostic strategies. We go on to discuss the alterations in cardiovascular physiology which influence positive- and negative-predictive values of standard noninvasive testing modalities in the ESLD population, and review the data regarding the safety and efficacy of invasive testing in the face of ESLD and its co-morbidities. Finally, based upon the totality of available data, we outline an evidence-based approach for the management of ischemia, heart failure and pulmonary vascular disease in this population. It is our hope that such evidence-driven strategies can be employed to more safely bridge appropriate candidates to liver transplant, and to improve their cardiovascular health and outcomes in the peri-operative period.

Renal dysfunction in patients with cirrhosis: Where do we stand?

Patients with cirrhosis and renal failure are high-risk patients who can hardly be grouped to form precise instructions for diagnosis and treatment. When it comes to evaluate renal function in patients with cirrhosis, determination of acute kidney injury (AKI), chronic kidney disease (CKD) or AKI on CKD should be made. First it should be excluded the prerenal causes of AKI. All cirrhotic patients should undergo renal ultrasound for measurement of renal resistive index in every stage of liver dysfunction and urine microscopy for differentiation of all causes of AKI. If there is history of dehydration on the ground of normal renal ultrasound and urine microscopy the diuretics should be withdrawn and plasma volume expansion should be tried with albumin. If the patient does not respond, the correct diagnosis is HRS. In case there is recent use of nephrotoxic agents or contrast media and examination shows shock, granular cast in urinary sediment and proteinuria above 0.5 g daily, acute tubular necrosis is the prominent diagnosis. Renal biopsy should be performed when glomerular filtration rate is between 30-60 mL/min and there are signs of parenchymal renal disease. The acute renal function is preferable to be assessed with modified AKIN. Patients with AKIN stage 1 and serum creatinine ≥ 1.5 mg/dL should be at close surveillance. Management options include hemodynamic monitoring and management of fluid balance and infections, potentially driving to HRS. Terlipressin is the treatment of choice in case of established HRS, administered until there are signs of improvement, but not more than two weeks. Midodrine is the alternative for therapy continuation or when terlipressin is unavailable. Norepinephrine has shown similar effect with terlipressin in patients being in Intensive Care Unit, but with much lower cost than that of terlipressin. If the patient meets the requirements for transplantation, dialysis and transjugular intrahepatic portosystemic shunt are the bridging therapies to keep the transplant candidate in the best clinical status. The present review clarifies the latest therapeutic modalities and the proposed recommendations and algorithms in order to be applied in clinical practice.