Transient and persistent acute kidney injury in acute liver failure

Long-Term Follow-Up of Kidney Function after Acute Liver Failure or Acute Liver Injury: A Cohort Study

Introduction

Acute liver failure (ALF) is a rare disease with high mortality. Acute kidney injury (AKI) following ALF is frequent. We assessed AKI impact on long-term kidney function among ALF survivors.

Methods

Observational cohort study including consecutive adult (age ≥16 years) patients with ALF or acute liver injury (ALI) admitted to a Portuguese tertiary center intensive care unit (ICU) between October 2013 and February 2020. KDIGO criteria were used to define AKI and chronic kidney disease (CKD). Primary outcome was the estimated glomerular filtration rate (eGFR), defined by the Chronic Kidney Disease Epidemiology Collaboration formula, at least 1 year after index ICU admission.

Results

Among 104 patients with ALF (n = 74) or ALI (n = 30), mean (SD) age was 43.7 (18.0) years, and 44 were male. Among all patients (n = 104), following adjustment for age and SOFA score, AKI during the first 7 ICU days (n AKI = 57 and n renal replacement therapy [RRT] = 32) was independently associated with all-cause mortality (adjusted HR [95% CI] 11.61 [1.49-90.34]; p = 0.019). Among hospital survivors with long-term kidney function available (n = 56), median (interquartile range) >1 year eGFR was 95.3 (75.0-107.7) mL/min/1.73 m2 (mean [SD] follow-up of 3.1 [1.6] years). Among these hospital survivors, following adjustment for baseline eGFR, AKI during the first 7 ICU days (n AKI = 19 and n RRT = 10) was not associated with >1 year eGFR (p = 0.15). At least 1 year after index ICU admission, 5 patients developed CKD, none RRT-dependent.

Conclusions

Among ALF or ALI survivors, AKI was not associated with significant long-term loss of kidney function.

Early Acute Kidney Injury Recovery in Elderly Patients Undergoing Valve Replacement Surgery

OBJECTIVES

This study was designed to determine the incidence, contributing factors, and prognostic implications of acute kidney injury (AKI) recovery patterns in patients who experienced AKI after valve replacement surgery (VRS).

DESIGN

A retrospective cohort study was conducted.

SETTING

The work took place in a postoperative care center in a single large-volume cardiovascular center.

PARTICIPANTS

Patients undergoing VRS between January 2010 and December 2019 were enrolled.

INTERVENTION

Patients were categorized into three groups based on their postoperative AKI status: non-AKI, AKI with early recovery (less than 48 hours), and persistent AKI.

MEASUREMENT AND MAIN RESULTS

The primary outcome was in-hospital major adverse clinical events. The secondary outcomes included in-hospital and 1-year mortality. A total of 4,161 patients who developed AKI following VRS were included. Of these, 1,513 (36.4%) did not develop postoperative AKI, 1,875 (45.1%) experienced AKI with early recovery, and 773 (18.6%) had persistent AKI. Advanced age, diabetes, New York Heart Association III-IV heart failure, moderate-to-severe renal dysfunction, anemia, and AKI stages 2 and 3 were identified as independent risk factors for persistent AKI. In-hospital major adverse clinical events occurred in 59 (3.9%) patients without AKI, 88 (4.7%) with early AKI recovery, and 159 (20.6%) with persistent AKI (p < 0.001). Persistent AKI was independently associated with an increased risk of in-hospital adverse events and 1-year mortality. In contrast, AKI with early recovery did not pose additional risk compared with non-AKI patients.

CONCLUSIONS

In patients who develop AKI following VRS, early AKI recovery does not pose additional risk compared with non-AKI. However, AKI lasting more than 48 hours is associated with an increased risk of in-hospital and long-term adverse outcomes.

Prevalence, Associated Factors, and Outcomes of Severe Acute Kidney Injury in Pediatric Acute Liver Failure: Single-Center Retrospective Study, 2003-2017

OBJECTIVES

Our aim was to determine the prevalence and explanatory factors associated with outcomes in children with acute liver failure (ALF) admitted to the PICU, who also develop severe acute kidney injury (AKI).

DESIGN

Retrospective cohort, 2003 to 2017.

SETTING

Sixteen-bed PICU in a university-affiliated tertiary care hospital.

PATIENTS

Admissions to the PICU with ALF underwent data review of the first week and at least 90-day follow-up. Patients with stages 2-3 AKI using the British Association of pediatric Nephrology definitions, or receiving continuous renal replacement therapy (CRRT) for renal indications, were defined as severe AKI. We excluded ALF cases on CRRT for hepatic-only indications.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Baseline characteristics, proportion with severe AKI, illness severity and interventions, and outcomes (i.e., transplant, survival with native liver, overall survival, duration of PICU stay, and mechanical ventilation). Ninety-four children with ALF admitted to the PICU were included. Over the first week, 29 had severe AKI, and another eight received CRRT for renal/mixed reno-hepatic indications; hence, the total severe AKI cohort was 37 of 94 (39.4%). In a multivariable logistic regression model, peak aspartate aminotransferase (AST) and requirement for inotropes on arrival were associated with severe AKI. Severe AKI was associated with longer PICU stay and duration of ventilation, and lower spontaneous survival with native liver. In another model, severe AKI was associated with greater odds of mortality (odds ratio 7.34 [95% CI, 1.90-28.28], p = 0.004). After 90 days, 3 of 17 survivors of severe AKI had serum creatinine greater than the upper limit of normal for age.

CONCLUSIONS

Many children with ALF in the PICU develop severe AKI. Severe AKI is associated with the timecourse of PICU admission and outcome, including survival with native liver. Future work should look at ALF goal directed renoprotective strategies at the time of presentation.

Acute kidney injury in acute liver failure: A narrative review

Acute kidney injury (AKI) is a frequent complication of acute liver failure (ALF) and it worsens the already worse prognoses of ALF. ALF is an uncommon disease, with varying etiologies and varying definitions in different parts of the world. There is limited literature on the impact of AKI on the outcome of ALF with or without transplantation. The multifaceted etiology of AKI in ALF encompasses factors such as hemodynamic instability, systemic inflammation, sepsis and direct nephrotoxicity. Indications of renal replacement therapy (RRT) for AKI in ALF patients extend beyond the conventional criteria for dialysis and continuous renal replacement therapy (CRRT) may have a role in transplant-free survival or bridge to liver transplantation (LT). LT is a life-saving option for ALF, so despite somewhat lower survival rates of LT in ALF patients with AKI, LT is not usually deferred. In this review, we will discuss the guidelines' recommended definition and classification of AKI in ALF, the impact of AKI in ALF, the pathophysiology of AKI and the role of CRRT and LT in ALF patients with AKI.

Persistent But Not Transient Acute Kidney Injury Was Associated With Lower Transplant-Free Survival in Patients With Acute Liver Failure: A Multicenter Cohort Study

OBJECTIVES

Acute liver failure (ALF) is an orphan disease often complicated by acute kidney injury (AKI). We assessed the impact of transient versus persistent AKI on survival in patients with ALF.

DESIGN

International multicenter retrospective cohort.

SETTING

U.S. ALF Study Group prospective registry.

PATIENTS

Patients with greater than or equal to 18 years and ALF in the registry from 1998 to 2016 were included. Patients with less than 3 days of follow-up, without kidney function evaluation on day 3, or with cirrhosis were excluded.

INTERVENTIONS

AKI was defined by Kidney Disease Improving Global Outcomes guidelines on day 1. Kidney recovery was defined on day 3 as transient AKI, by a return to no-AKI within 48 hours or persistent AKI if no such recovery or renal replacement therapy (RRT) was observed. Primary outcome was transplant-free survival (TFS) at 21 days.

MEASUREMENTS AND MAIN RESULTS

Among 1,071 patients with ALF, 339 (31.7%) were males, and median (interquartile range) age was 39 years (29-51 yr). Acetaminophen-related ALF was found in 497 patients (46.4%). On day 1, 485 of 1,071 patients (45.3%) had grade 3-4 hepatic encephalopathy (HE), 500 of 1,070 (46.7%) required invasive mechanical ventilation (IMV), 197 of 1,070 (18.4%) were on vasopressors, and 221 of 1,071 (20.6%) received RRT. On day 1, 673 of 1,071 patients (62.8%) had AKI. On day 3, 72 of 1,071 patients (6.7%) had transient AKI, 601 of 1,071 (56.1%) had persistent AKI, 71 of 1,071 (6.6%) had late onset AKI, and 327 of 1,071 (30.5%) remained without AKI. Following adjustment for confounders (age, sex, race, etiology, HE grade, use of IMV and vasopressors, international normalized ratio, and year), although persistent acute kidney injury (adjusted odds ratio [aOR] [95% CI] 0.62 [0.44-0.88]) or late onset AKI (aOR [95% CI] 0.48 [0.26-0.89]) was associated with lower TFS, transient AKI was not (aOR [95% CI] 1.89 [0.99-3.64]).

CONCLUSIONS

In a multicenter cohort of patients with ALF, persistent but not transient AKI was independently associated with lower short-term TFS.

Development and External Verification of a Nomogram for Patients with Persistent Acute Kidney Injury in the Intensive Care Unit

Background

We aimed to identify the affecting features of persistent acute kidney injury (pAKI) for patients in intensive care units (ICU).

Methods

The Medical Information Mart for Intensive Care IV (MIMIC-IV) database and eICU Collaborative Research Database (eICU-CRD) were used to identify AKI patients with and without duration of more than 48 hours. Least absolute shrinkage and selection operator (LASSO) regression and support vector machine (SVM-RFE) were utilized to screen for the significant clinical indexes associated with pAKI. Predictive nomogram was created based on the above informative parameters to predict the probability of pAKI.

Results

LASSO regression and SVM-RFE revealed that serum albumin, chronic kidney disease, AKI stage, sequential organ failure assessment score, lactate and renal replacement therapy during the first day were significantly associated with pAKI in the training cohort. The predictive nomogram based on the six predictors exhibited good predictive performance as calculated by C-index 0.730 (95% CI 0.710-0.749) in the training group, 0.702 (95% CI 0.672-0.722) in the internal validation set and 0.704 (0.677-0.731) in the external validation cohort for the prediction of pAKI. Moreover, the predictive nomogram exhibited not only encouraging calibration ability, but also great clinical utility in the training group, in the internal validation group as well as in the external validation cohort.

Conclusion

Serum albumin, CKD, AKI stage, SOFA score, lactate, RRT during the first day were closely associated with pAKI in patients in ICU. The predictive nomogram for pAKI manifested good predictive ability for the identification of ICU patients with pAKI.

Impact of sterile leukocyturia on outcome of critically ill patients with severe acute kidney injury

INTRODUCTION

The role of immunological mechanisms on renal regeneration and functional recovery after an episode of Acute Kidney Injury (AKI) is still understudied. We aim to evaluate the impact of sterile leukocyturia on outcomes of critically-ill AKI patients.

METHODS

A retrospective analysis of critically-ill patients with stage ≥2 AKI by KDIGO was performed. Patients with urinary tract infection, previous renal replacement therapy, chronic kidney disease stage >3 and kidney, urinary tract or prostatic cancer were excluded. Sterile leukocyturia was defined as a positive leukocyte esterase value.

RESULTS

108 patients with stage ≥2 AKI were included, 39.8% of which had sterile leukocyturia. AKI patients with sterile leukocyturia were older, had more cardiovascular disease and a lower baseline renal function (p < 0.05). They had a higher serum creatinine and leukocytosis at admission, were more frequently septic (p < 0.05) and had more persistent AKI by both KDIGO criteria at multivariable analysis (OR 6.130, 95% CI 2.007-18.747).

CONCLUSION

Sterile leukocyturia was associated with different patient baseline and AKI characteristics and more persistent AKI by both KDIGO criteria. Sterile leukocyturia may represent a surrogate marker of renal inflammation during AKI.

Long-term consequences of acute kidney injury: a narrative review

The incidence of acute kidney injury (AKI) has increased in the past decades. AKI complicates up to 15% of hospitalizations and can reach up to 50-60% in critically ill patients. Besides the short-term impact of AKI in patient outcomes, several studies report the association between AKI and adverse long-term outcomes, such as recurrent AKI episodes in 25-30% of cases, hospital re-admissions in up to 40% of patients, an increased risk of cardiovascular events, an increased risk of progression of chronic kidney disease (CKD) after AKI and a significantly increased long-term mortality. Despite the long-term impact of AKI, there are neither established guidelines on the follow-up care of AKI patients, nor treatment strategies to reduce the incidence of sequelae after AKI. Only a minority of patients have been referred to nephrology post-discharge care, despite the evidence of improved outcomes associated with nephrology referral by addressing cardiovascular risk and risk of progression to CKD. Indeed, AKI survivors should have specialized nephrology follow-up to assess kidney function after AKI, perform medication reconciliation, educate patients on nephrotoxic avoidance and implement strategies to prevent CKD progression. The authors provide a comprehensive review of the transition from AKI to CKD, analyse the current evidence on the long-term outcomes of AKI and describe predisposing risk factors, highlight the importance of follow-up care in these patients and describe the current therapeutic strategies which are being investigated on their impact in improving patient outcomes.

The need for disruptive innovation in acute kidney injury

Acute kidney injury (AKI) is a threatening medical condition associated with poor outcomes at different settings. The development of standardized diagnostic criteria and new biomarkers addressed significant clinical impacts of AKI and the need for an early AKI detection, respectively. There have been some breakthroughs in understanding the pathogenesis of AKI through basic research; however, treatments against AKI aside from renal replacement therapy (RRT) have not shown adequate successful results. Biomarkers that could identify good responders to certain treatment are expected to facilitate translation of basic research findings. Most patients with severe AKI treated with RRT died due to multiple-organ failure, not renal dysfunction. Hence, it is essential to identify other organ dysfunctions induced by AKI as organ crosstalk. Also, a multidisciplinary approach of critical care nephrology is needed to evaluate a complex organ crosstalk in AKI. For disruptive innovation for AKI, we further explore these new aspects of AKI, which previously were considered outside the scope of nephrology.

Detoxification of bilirubin and bile acids with intermittent coupled plasmafiltration and adsorption in liver failure (HERCOLE study)

Background

CPFA is an extracorporeal treatment used in severe sepsis to remove circulating proinflammatory cytokines. Limited evidence exists on the effectiveness of bilirubin adsorption by the hydrophobic styrenic resin, the distinctive part of CPFA. The aim of this study is to validate CPFA effectiveness in liver detoxification.

Methods

In this prospective observational study, we enrolled patients with acute or acute-on-chronic liver failure (serum total bilirubin > 20 mg/dL or MELD Score > 20) hospitalized from June 2013 to November 2017. CPFA was performed using the Lynda (Bellco/MedTronic, Mirandola, Italy) or the Amplya (Bellco/MedTronic, Mirandola, Italy) machines. Anticoagulation was provided with unfractionated heparin or citrate. Bilirubin and bile acids reduction ratios per session (RRs) were the main parameters for hepatic detoxification.

Results

Twelve patients with acute (n = 3) or acute-on-chronic (n = 9) liver failure were enrolled. Alcohol was the main cause of liver disease. Thirty-one CPFA treatments of 6 h each were performed, 19 with heparin and 12 with citrate. RRs was 28.8% (range 2.2–40.5) for total bilirubin, 32.7% (range 8.3–48.9) for direct bilirubin, 29.5% (range 6.5–65.4) for indirect bilirubin and 28.9% (16.7- 59.7) for bile acids. One patient received liver transplantation and 8/9 were alive at 1 year of follow-up. Three patients (25%) died: 2 during hospitalization and 1 for a cardiac event at 4 months of follow up with restored liver function.

Conclusions

CPFA resulted to be effective in liver detoxification. Thus, it may be considered as a “bridge technique” both to the liver transplant and to the recovery of the basal liver function.

Comparison of Prognostic Models in Acute Liver Failure: Decision is to be Dynamic

Background and aims

Acute liver failure (ALF) is a rare disease entity with a high mortality. Management is dependent on accurate prognostication.

Materials and methods

One hundred consecutive patients presenting with ALF were prospectively evaluated. The King's college criteria (KCC), ALF early dynamic model (ALFED), sequential organ failure assessment (SOFA) score, and acute physiology and health evaluation II (APACHE II) scores were compared to predict mortality.

Results

There were significant differences in means of all the scores between survivors and nonsurvivors. The SOFA 48 hours had the highest area under receiver operating characteristic curve (AUC) (0.857) closely followed by the ALFED score (0.844). The optimal cutoff for the SOFA score at 48 hours to predict subsequent survival outcome is ≥10 and for the ALFED score is ≥5. Sequential organ failure assessment 48 hours had a good sensitivity of 87%, and the ALFED score showed a good specificity of 84%. The decision curve analysis showed that between a threshold probability of 0.13 and 0.6, use of the SOFA score provided the maximum net benefit and at threshold probabilities of >0.6, the use of ALFED score provided the maximum clinical benefit.

Conclusion

Dynamic scoring results in better prognostication in ALF. The SOFA 48 hours and ALFED score have good prognostication value in nonacetaminophen-induced liver failure.

How to cite this article

Saluja V, Sharma A, Pasupuleti SSR, Mitra LG, Kumar G, Agarwal PM. Comparison of Prognostic Models in Acute Liver Failure: Decision is to be Dynamic. Indian J Crit Care Med 2019;23(12):574–581.