Hepatorenal syndrome

Hepatorenal syndrome: pathophysiology and evidence-based management update

Hepatorenal syndrome (HRS) is a functional renal failure that develops in patients with advanced hepatic cirrhosis with ascites and in those with fulminant hepatic failure. The prevalence of HRS varies among studies but in general it is the third most common cause of acute kidney injury (AKI) in cirrhotic patients after pre-renal azotemia and acute tubular necrosis. HRS carries a grim prognosis with a mortality rate approaching 90% three months after disease diagnosis. Fortunately, different strategies have been proven to be successful in preventing HRS. Although treatment options are available, they are not universally effective in restoring renal function but they might prolong survival long enough for liver transplantation, which is the ultimate treatment. Much has been learned in the last two decades regarding the pathophysiology and management of this disease which lead to notable evolution in the HRS definition and better understanding on how best to manage HRS patients. In the current review, we will summarize the recent advancement in epidemiology, pathophysiology, and management of HRS.

INASL-ISN Joint Position Statements on Management of Patients with Simultaneous Liver and Kidney Disease

Renal dysfunction is very common among patients with chronic liver disease, and concomitant liver disease can occur among patients with chronic kidney disease. The spectrum of clinical presentation and underlying etiology is wide when concomitant kidney and liver disease occur in the same patient. Management of these patients with dual onslaught is challenging and requires a team approach of hepatologists and nephrologists. No recent guidelines exist on algorithmic approach toward diagnosis and management of these challenging patients. The Indian National Association for Study of Liver (INASL) in association with Indian Society of Nephrology (ISN) endeavored to develop joint guidelines on diagnosis and management of patients who have simultaneous liver and kidney disease. For generating these guidelines, an INASL-ISN Taskforce was constituted, which had members from both the societies. The taskforce first identified contentious issues on various aspects of simultaneous liver and kidney diseases, which were allotted to individual members of the taskforce who reviewed them in detail. A round-table meeting of the Taskforce was held on 20-21 October 2018 at New Delhi to discuss, debate, and finalize the consensus statements. The evidence and recommendations in these guidelines have been graded according to the Grading of Recommendations Assessment Development and Evaluation (GRADE) system with minor modifications. The strength of recommendations (strong and weak) thus reflects the quality (grade) of underlying evidence (I, II, III). We present here the INASL-ISN Joint Position Statements on Management of Patients with Simultaneous Liver and Kidney Disease.

Optimal Management of Cirrhotic Ascites: A Review for Internal Medicine Physicians

Clinical history of liver cirrhosis is characterised by two phases: the asymptomatic phase, also termed 'compensated cirrhosis', and the phase of complications due to the development of portal hypertension and liver dysfunction, also termed 'decompensated cirrhosis', in which patients may develop ascites, the most frequent and clinically relevant complication of liver cirrhosis. Ascites can be classified into uncomplicated and complicated according to the development of refractoriness, spontaneous bacterial peritonitis (SBP) or the association with hepatorenal syndrome (HRS). In this narrative review, we will extensively discuss the optimal pharmacological and non-pharmacological management of cirrhotic ascites with the aim to offer an updated practical guide to Internal Medicine physicians. According to the amount of fluid in the abdominal cavity, uncomplicated ascites is graded from 1 to 3, and the cornerstone of its management consists of restriction of salt intake, diuretics and large-volume paracentesis (LVP); in recent years, long-term administration of human albumin has acquired a new interesting role. Refractory ascites is primarily managed with LVP and transjugular intrahepatic portosystemic shunt (TIPS) placement in selected patients. The occurrence of renal impairment, especially HRS, worsens the prognosis of patients with cirrhotic ascites and deserves a specific treatment. Also, the management of SBP faces the rising and alarming spread of antibiotic resistance. Hepatic hydrothorax may even complicate the course of the disease and its management is a challenge. Last but not least, liver transplantation (LT) is the ultimate and more effective measure to offer to patients with cirrhotic ascites, particularly when complications occur.

Outcomes of liver transplantation in patients with hepatorenal syndrome

Hepatorenal syndrome (HRS) plays an important role in patients with liver cirrhosis on the wait list for liver transplantation (LT). The 1 and 5-year probability of developing HRS in cirrhotic with ascites is 20% and 40%, respectively. In this article, we reviewed current concepts in HRS pathophysiology, guidelines for HRS diagnosis, effective treatment options presently available, and controversies surrounding liver alone vs simultaneous liver kidney transplant (SLKT) in transplant candidates. Many treatment options including albumin, vasoconstrictors, renal replacement therapy, and eventual LT have remained a mainstay in the treatment of HRS. Unfortunately, even after aggressive measures such as terlipressin use, the rate of recovery is less than 50% of patients. Moreover, current SLKT guidelines include: (1) estimation of glomerular filtration rate of 30 mL/min or less for 4-8 wk; (2) proteinuria > 2 g/d; or (3) biopsy proven interstitial fibrosis or glomerulosclerosis. Even with these updated criteria there is a lack of consistency regarding long-term benefits for SLKT vs LT alone. Finally, in regards to kidney dysfunction in the post-transplant setting, an estimation of glomerular filtration rate < 60 mL/min per 1.73 m² may be associated with an increased risk of patients having long-term end stage renal disease. HRS is common in patients with cirrhosis and those on liver transplant waitlist. Prompt identification and therapy initiation in transplant candidates with HRS may improve post-transplantation outcomes. Future studies identifying optimal vasoconstrictor regimens, alternative therapies, and factors predictive of response to therapy are needed. The appropriate use of SLKT in patients with HRS remains controversial and requires further evidence by the transplant community.

Terlipressin Plus Albumin Is More Effective Than Albumin Alone in Improving Renal Function in Patients With Cirrhosis and Hepatorenal Syndrome Type 1

BACKGROUND & AIMS

Hepatorenal syndrome type 1 (HRS-1) in patients with cirrhosis and ascites is a functional, potentially reversible, form of acute kidney injury characterized by rapid (<2 wk) and progressive deterioration of renal function. Terlipressin is a synthetic vasopressin analogue that acts, via vascular vasopressin V1 receptors, as a systemic vasoconstrictor. We performed a phase 3 study to evaluate the efficacy and safety of intravenous terlipressin plus albumin vs placebo plus albumin in patients with HRS-1.

METHODS

Adult patients with cirrhosis, ascites, and HRS-1 (based on the 2007 International Club of Ascites criteria of rapidly deteriorating renal function) were assigned randomly to groups given intravenous terlipressin (1 mg, n = 97) or placebo (n = 99) every 6 hours with concomitant albumin. Treatment continued through day 14 unless the following occurred: confirmed HRS reversal (CHRSR, defined as 2 serum creatinine [SCr] values ≤1.5 mg/dL, at least 40 hours apart, on treatment without renal replacement therapy or liver transplantation) or SCr at or above baseline on day 4. The primary end point was the percentage of patients with confirmed CHRSR. Secondary end points included the incidence of HRS reversal (defined as at least 1 SCr value ≤1.5 mg/dL while on treatment), transplant-free survival, and overall survival. The study was performed at 50 investigational sites in the United States and 2 in Canada, from October 2010 through February 2013.

RESULTS

Baseline demographic/clinical characteristics were similar between groups. CHRSR was observed in 19 of 97 patients (19.6%) receiving terlipressin vs 13 of 99 patients (13.1%) receiving placebo (P = .22). HRS reversal was achieved in 23 of 97 (23.7%) patients receiving terlipressin vs 15 of 99 (15.2%) receiving placebo (P = .13). SCr decreased by 1.1 mg/dL in patients receiving terlipressin and by only 0.6 mg/dL in patients receiving placebo (P < .001). Decreases in SCr and survival were correlated (r(2) = .882; P < .001). Transplant-free and overall survival were similar between groups. A significantly greater proportion of patients with CHRSR who received terlipressin survived until day 90 than patients who did not have CHRSR after receiving terlipressin (P < .001); this difference was not observed in patients who did vs did not have CHRSR after receiving placebo (P = .28). There were similar numbers of adverse events in each group, but patients in the terlipressin group had more ischemic events.

CONCLUSIONS

Terlipressin plus albumin was associated with greater improvement in renal function vs albumin alone in patients with cirrhosis and HRS-1. Patients had similar rates of HRS reversal with terlipressin as they did with albumin. ClinicalTrials.gov no: NCT01143246.

Heart-kidney crosstalk and role of humoral signaling in critical illness

Organ failure in the heart or kidney can initiate various complex metabolic, cell-mediated and humoral pathways affecting distant organs, contributing to the high therapeutic costs and significantly higher morbidity and mortality. The universal outreach of cells in an injured state has myriad consequences to distant organ cells and their milieu. Heart performance and kidney function are closely interconnected and communication between these organs occurs through a variety of bidirectional pathways. The term cardiorenal syndrome (CRS) is often used to describe this condition and represents an important model for exploring the pathophysiology of cardiac and renal dysfunction. Clinical evidence suggests that tissue injury in both acute kidney injury and heart failure has immune-mediated inflammatory consequences that can initiate remote organ dysfunction. Acute cardiorenal syndrome (CRS type 1) and acute renocardiac syndrome (CRS type 3) are particularly relevant in high-acuity medical units. This review briefly summarizes relevant research and focuses on the role of signaling in heart-kidney crosstalk in the critical care setting.

Neutrophil gelatinase-associated lipocalin in prediction of mortality in patients with hepatorenal syndrome: a prospective observational study

BACKGROUND & AIMS

Hepatorenal syndrome (HRS) is a severe complication of cirrhosis which is characterized by renal dysfunction and associated with poor survival. Neutrophil gelatinase-associated lipocalin (NGAL) is a troponin-like biomarker for human acute kidney injury. We aimed to investigate levels of plasma and urine NGAL in HRS and predictive ability of these markers for all-cause mortality, in HRS, stable cirrhosis and control subjects.

METHODS

A total of 64 patients with cirrhosis (8 patients with type 1 HRS, 22 with type 2 HRS, and 34 without HRS) and 23 control subjects were included in the study. Blood and urine samples were measured with Human NGAL sandwich ELISA. Patients were followed up prospectively.

RESULTS

Patients with type 1 and type 2 HRS had significantly higher plasma and urine NGAL levels compared with stable cirrhosis and control subjects. Cox regression analysis showed that plasma NGAL and MELD-Na scores were independent predictors of mortality. ROC-curve analysis showed that the plot of the plasma NGAL, urine NGAL, MELD-Na and Child-Turcot-Pugh score could predict all-cause mortality in cirrhotic patients' area under the curve (AUC 0.819, 0.686, 0.807 and 0.795 respectively).

CONCLUSIONS

NGAL could predict mortality in patients with HRS independent of other commonly used risk factors.

Hepatorenal syndrome and novel advances in its management

Hepatorenal syndrome is a complication of end stage liver disease. It is a unique form of functional renal failure related to kidney vasoconstriction in the absence of underlying kidney pathology. Hepatorenal syndrome is classified into 2 types: type-1 HRS shows a rapid and progressive decline in renal function with a very poor prognosis (median survival of about 2 weeks); type-2 HRS has a more stable kidney failure, with a median survival of 6 months; its main clinical manifestation is refractory ascites. The most appropriate therapy for HRS is liver transplantation but only a minority of HRS patients undergo the procedure due to the high mortality; survival among liver transplant recipients is lower in HRS than among their counterparts without HRS. A large body of evidence, based on observational studies and randomized controlled trials, has been accumulated in the last decade showing that terlipressin represents a milestone in the management of HRS. According to our meta-analysis of randomized trials comparing terlipressin vs. placebo (five trials, n=243 patients), the pooled rate of patients who reversed HRS by terlipressin was 8.09 (95% CI, 3.52; 18.59) (P<0.001). Among vasoconstrictors, terlipressin (a V1 vasopressin agonist) is the most widely used; however, noradrenaline is another good choice. Vasoconstrictor drugs alone or with albumin reduce mortality compared with no intervention or albumin (RR of mortality, 0.82; 95% Confidence Intervals, 0.70; 0.96) (P<0.01). Two series of patients with HRS recurrence after the first treatment have recently shown that long-term therapy with terlipressin and albumin is beneficial as a bridge to liver transplant. Nevertheless, recovery of renal function can be achieved in less than 50% of patients with HRS after terlipressin use and the recovery of renal function may also be partial in patients who are defined full responders. Renal replacement therapy should not be considered a first-line therapy for HRS Clinical trials are under way in order to assess efficacy and safety of novel therapeutic agents for the treatment of type-1 and type-2 HRS.

Anesthesia for Liver Transplantation

Orthotopic liver transplantation is the only definitive treatment for end-stage liver disease. More than 6000 procedures are performed in the United States annually with excellent survival rates. The shortage of donor organs leads to continued interest in techniques to enlarge the potential donor pool. Patients presenting for liver transplant suffer from important cardiovascular, respiratory, renal, neurological, and gastroenterological comorbidity. In the Western world, liver failure is increasingly caused by steatohepatitis, and transplant candidates are thus becoming older and more comorbid. The role of the transplant anesthesiologist is highly important in the preoperative assessment, intraoperative management, and postoperative care of these complex and sick patients. Appropriate investigation and management of comorbidities such as coronary artery disease and portopulmonary hypertension is controversial and differs between programs. The transplant procedure is a major surgery, and although massive transfusion is no longer commonplace, there is potential for significant hemodynamic instability, coagulopathy, and metabolic disturbance. Liver transplant surgery can be divided into the preanhepatic phase, the anhepatic phase, and the reperfusion phase, with important anesthetic considerations at each point.  An understanding of the surgical techniques used for vascular exclusion of the liver and the role of venovenous bypass is crucial for the anesthesiologist. Recent trends in perioperative care include the use of antifibrinolytic drugs and point-of-care coagulation tests, intraoperative renal replacement therapy, and “fast-track” extubation and postoperative care. Care of patients with fulminant hepatic failure or those receiving split-liver grafts requires special consideration.

Hepatorenal syndrome

Hepatorenal syndrome (HRS) is defined as a functional renal failure in patients with liver disease with portal hypertension and it constitutes the climax of systemic circulatory changes associated with portal hypertension. This term refers to a precisely specified syndrome featuring in particular morphologically intact kidneys, where regulatory mechanisms have minimised glomerular filtration and maximised tubular resorption and urine concentration, which ultimately results in uraemia. The syndrome occurs almost exclusively in patients with ascites. Type 1 HRS develops as a consequence of a severe reduction of effective circulating volume due to both an extreme splanchnic arterial vasodilatation and a reduction of cardiac output. Type 2 HRS is characterised by a stable or slowly progressive renal failure so that its main clinical consequence is not acute renal failure, but refractory ascites, and its impact on prognosis is less negative. Liver transplantation is the most appropriate therapeutic method, nevertheless, only a few patients can receive it. The most suitable “bridge treatments” or treatment for patients ineligible for a liver transplant include terlipressin plus albumin. Terlipressin is at an initial dose of 0.5-1 mg every 4 h by intravenous bolus to 3 mg every 4 h in cases when there is no response. Renal function recovery can be achieved in less than 50% of patients and a considerable decrease in renal function may reoccur even in patients who have been responding to therapy over the short term. Transjugular intrahepatic portosystemic shunt plays only a marginal role in the treatment of HRS.