Acute kidney injury in critically ill cirrhotic patients: a review

The impact of perioperative positive fluid balance on postoperative acute kidney injury in patients undergoing open hepatectomy: A retrospective single center cohort study

BACKGROUND

Low central venous pressure (CVP) or fluid restriction strategies are frequently employed during liver parenchymal resection to minimize intraoperative blood loss. However, both hypovolemia and excessive fluid administration can impair organ perfusion, increasing the risk of renal dysfunction and acute kidney injury (AKI). This study explores the relationship between perioperative fluid management strategies and renal outcomes in patients undergoing hepatectomy.

METHOD

A retrospective single-center cohort study was conducted involving 691 patients who underwent an open hepatectomy. Patients were categorized by positive fluid balance: <1 Liter, 1-2 Liters, and >2 Liters. Propensity score was used for matching among the groups. The incidence of acute kidney injury (AKI) was compared. Multivariable logistic regression analyzed the correlation between fluid balance and AKI risk.

RESULT

The overall incidence of AKI was 11.58%, with the highest occurrence in the group with a fluid balance greater than 2 Liters. This group demonstrated a significantly higher relative risk of developing AKI compared to those with positive fluid balances of <1 Liter and 1-2 Liters (adjusted RR 1.85, p = 0.042, 95% CI 1.02-3.38). An increase in fluid balance was associated with a higher incidence rate ratio for AKI (p = 0.016). Additionally, an operating time >5 hours, blood loss >1000 ml, and Child-Turcotte-Pugh class B and C were significantly associated with an increased risk of post-hepatectomy AKI.

CONCLUSION

Maintaining a fluid balance of 1-2 liters during hepatectomy is crucial to reducing the risk of postoperative AKI, while balances above 2 liters significantly increase it. Prolonged operating times, high blood loss, and advanced liver disease also elevate AKI risk, emphasizing the need for careful fluid management.

A novel risk-predicted nomogram for acute kidney injury progression in decompensated cirrhosis: a double-center study in Vietnam

OBJECTIVES

Acute kidney injury (AKI) is commonly encountered in patients hospitalized for decompensated cirrhosis and is associated with prolonged hospital stays, increased treatment burden, and even mortality. The present study aimed to determine the prevalence of and develop a predictive nomogram for AKI in patients with decompensated cirrhosis.

METHODS

This cross-sectional, double-center study involved 544 patients hospitalized with decompensated cirrhosis. Acute kidney injury was diagnosed using American Gastroenterological Association's guidelines with one more criterion: an increase in serum creatinine ≥ 0.3 mg/dL within 48 h or an increase in serum creatinine ≥ 50% compared to baseline serum creatinine or when the urine output is reduced below 0.5 mL/kg/h for > 6 h. We used the Bayesian model averaging method find the optimal model for predicting AKI. A predictive nomogram was also developed to enable risk prediction.

RESULTS

The overall AKI prevalence was 26.7% (95% Confidence interval [CI] 25.7-27.7). The optimal model for predicting AKI included diuretic therapy (odds ratio [OR]: 5.55; 95%CI 3.31-9.33), infection (OR: 2.06; 95%CI 1.31-3.22), ascites (OR: 3.20; 95%CT: 1.67-6.13), Child-Pugh group C (OR: 2.91; 95%CI 1.84-4.62), serum potassium (OR per 1 mmol/L increase: 1.62; 95%CI 1.25-2.1) and serum chloride (OR per 1 mmol/L decrease: 1.03; 95%CI 1.01-1.06). The area under the receiver operating characteristic curve was 0.8, with a 95%CI ranging from 0.75 to 0.84.

CONCLUSIONS

Acute kidney injury was relatively common among patients hospitalized for decompensated cirrhosis. A novel nomogram-including diuretic therapy, infection, ascites, Child-Pugh group C, serum potassium and, serum chloride, was helpful for the selective screening of AKI in patients with decompensated cirrhosis.

Prediction models combining zonulin, LPS, and LBP predict acute kidney injury and hepatorenal syndrome-acute kidney injury in cirrhotic patients

The development of acute kidney injury (AKI) and hepatorenal syndrome-acute kidney injury (HRS-AKI) in cirrhosis has been associated with intestinal barrier dysfunction and gut-kidney crosstalk. We use the related markers such as zonulin, lipopolysaccharides (LPS), and lipopolysaccharide-binding protein (LBP) to predict AKI and HRS-AKI in cirrhotic patients and evaluate their in vitro effects on intestinal (Caco-2) cells and renal tubular (HK-2) cells. From 2013 to 2020, we enrolled 70 cirrhotic patients and developed prediction models for AKI and HRS-AKI over a six-month period. There were 13 (18.6%) and 8 (11.4%) cirrhotic patients developed AKI and HRS-AKI. The prediction models incorporated zonulin, LPS, LBP, C-reactive protein, age, and history of hepatitis B for AKI, and zonulin, LPS, LBP, total bilirubin, and Child-Pugh score for HRS-AKI. The area under curve (AUC) for the prediction of AKI and HRS-AKI was 0.94 and 0.95, respectively. Furthermore, the conditioned medium of LPS+hrLBP pre-treated Caco-2 cells induced apoptosis, necrosis, and zonulin release in HK-2 cells, demonstrating the communication between them. This study found that zonulin, LPS, and LBP are potential practical markers for predicting AKI and HRS-AKI in cirrhotic patients, which may serve as potential targets for renal outcomes in cirrhotic patients.

Intraoperative Renal Replacement Therapy in Orthotopic Liver Transplantation

Acute kidney injury in patients admitted to the hospital for liver transplantation is common, with up to 80% of pretransplant patients having some form of acute kidney injury. Many of these patients start on dialysis prior to their transplant and have it continued intraoperatively during their surgery. This review discusses the limited existing literature and expert opinion around the indications and outcomes around intraoperative dialysis (intraoperative renal replacement therapy) during liver transplantation. More specifically, we discuss which patients may benefit from intraoperative renal replacement therapy and the impact of hyponatremia and hyperammonemia on the dialysis prescription. Additionally, we discuss the complex interplay between anesthesia and intraoperative renal replacement therapy and how the need for clearance and ultrafiltration changes throughout the different phases of the transplant (preanhepatic, anhepatic, and postanhepatic). Lastly, this review will cover the limited data around patient outcomes following intraoperative renal replacement therapy during liver transplantation as well as the best evidence for when to stop dialysis.

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.

Invasive hemodynamic parameters in patients with hepatorenal syndrome

Background

Hepatorenal syndrome (HRS), a form of kidney dysfunction frequent in cirrhotic patients, is characterized by low filling pressures and impaired kidney perfusion due to peripheral vasodilation and reduced effective circulatory volume. Cardiorenal syndrome (CRS), driven by renal venous hypertension and elevated filling pressures, is a separate cause of kidney dysfunction in cirrhotic patients. The two entities, however, have similar clinical phenotypes. To date, limited invasive hemodynamic data are available to help distinguish the primary forces behind worsened kidney function in cirrhotic patients.

Objective

Our aim was to analyze invasive hemodynamic profiles and kidney outcomes in patients with cirrhosis who met criteria for HRS.

Methods

We conducted a single center retrospective study among cirrhotic patients with worsening kidney function admitted for liver transplant evaluation between 2010 and 2020. All met accepted criteria for HRS and underwent concurrent right heart catheterization (RHC).

Results

127 subjects were included. 79 had right atrial pressure >10 mmHg, 79 had wedge pressure >15 mmHg, and 68 had both. All patients with elevated wedge pressure were switched from volume loading to diuretics resulting in significant reductions between admission and post diuresis creatinine values (2.0 [IQR 1.5–2.8] vs 1.5 [IQR 1.2–2.2]; p = 0.003).

Conclusion

62% of patients diagnosed with HRS by clinical criteria have elevated filling pressures. Improvement of renal function after diuresis suggests the presence of CRS physiology in these patients. Invasive hemodynamic data profiling can lead to meaningful change in management of cirrhotic patients with worsened kidney function, guiding appropriate therapies based on filling pressures.

Advances in the Diagnosis and Treatment of Acute Kidney Injury in Cirrhosis Patients

Liver cirrhosis is a common progressive and chronic clinical liver disease. Due to the strong compensation ability of the liver, no obvious symptoms develop in the early stage. However, multiple systems are involved in decompensation of the liver. Acute kidney injury (AKI) is one of the most serious complications, characterized by a sharp drop in the glomerular filtration rate (GFR); a rapid increase in Scr and BUN, as well as sodium and water storage; and a disturbance of acid-base balance. The mortality rate is high, and the prognosis is very poor. Thus, it is important to make a definite diagnosis and initiate treatment in the early stage to decrease mortality and improve the prognosis. Although diagnosing liver cirrhosis with serum creatinine has many shortcomings, a dynamic change in this marker is still the main diagnostic criterion for AKI. Identifying new markers of kidney injury with clinical value has also become an increasing focus of research. In this text, we review recent changes regarding categorization of AKI diagnostic criteria as well as new markers of AKI and treatments for cirrhosis-related AKI.

Peritoneal ultrafiltration for refractory fluid overload and ascites due to pulmonary arterial hypertension

Pulmonary hypertension is a common finding in patients with advanced liver disease. Similarly, among patients with advanced pulmonary arterial hypertension, right heart failure leads to congestive hepatopathy. Diuretic resistant fluid overload in both advanced pulmonary hypertension and chronic liver disease is a demanding challenge for physicians. Venous congestion and ascites-induced increased intra-abdominal pressure are essential regarding recurrent hospitalization, morbidity and mortality. Due to impaired right-ventricular function, many patients cannot tolerate extracorporeal ultrafiltration. Peritoneal dialysis, a well-established, hemodynamically tolerated treatment for outpatients may be a good alternative to control fluid status. We present a patient with pulmonary arterial hypertension and congestive hepatopathy hospitalized for over 3 months due to ascites induced refractory volume overload treated with peritoneal ultrafiltration. We report the treatment benefits on fluid balance, cardiorenal and pulmonary function, as well as its safety. In conclusion, we report a case in which peritoneal ultrafiltration was an efficient treatment option for refractory ascites in patients with congestive hepatopathy.

Acute kidney injury in acute liver failure: a review

Acute liver failure is a rare and often devastating condition consequent on massive liver cell necrosis that frequently affects young, previously healthy individuals resulting in altered cognitive function, coagulopathy and peripheral vasodilation. These patients frequently develop concurrent acute kidney injury (AKI). This abrupt and sustained decline in renal function, through a number of pathogenic mechanisms such as renal hypoperfusion, direct drug-induced nephrotoxicity or sepsis/systemic inflammatory response contributes to increased morbidity and is strongly associated with a worse prognosis. Improved understanding of the pathophysiology AKI in the context of acute liver failure may be beneficial in a number of areas; the development of new and sensitive biomarkers of renal dysfunction, refining prognosis and organ allocation, and ultimately leading to the development of novel treatment strategies, these issues are discussed in more detail in this expert review.

Predicting the development of acute kidney injury in liver cirrhosis--an analysis of glomerular filtration rate, proteinuria and kidney injury biomarkers

BACKGROUND

The timely diagnosis of acute kidney injury (AKI) in liver cirrhosis is challenging.

AIM

To evaluate whether quantification of glomerular filtration rate (GFR), proteinuria and kidney injury biomarkers can accurately predict the development of AKI.

METHODS

A prospective cohort analysis of patients with cirrhosis was performed. Measures of baseline kidney function included serum creatinine, iohexol clearance and urine protein:creatinine ratio. Blood and urine samples were collected daily. A retrospective analysis of cystatin C GFR and neutrophil gelatinase-associated lipocalin (NGAL) measured 48 h prior to the diagnosis of AKI was undertaken to evaluate their ability to predict the development of AKI.

RESULTS

Eighteen of the 34 cirrhosis patients studied developed AKI. A GFR <60 mL/min/1.73 m(2) was identified in 56% with Iohexol clearance compared to 8% using the four-variable modified diet in renal disease formula (P < 0.0001). Prediction of AKI, 48 h prior to the development of AKI with cystatin C GFR and serum NGAL concentration were similar; area under the receiver operating curve (AUROC) values 0.74 (0.51-0.97), P = 0.04 and 0.72 (0.52-0.92), P = 0.02 respectively. The development of AKI was strongly predicted by urine protein:creatinine ratio above the cut-off of >30 (equivalent to 300 mg/day of proteinuria) sensitivity 82% (57-96) and specificity 80% (52-96), AUROC 0.86 (0.73-0.98), P ≤ 0.0001. [OR 21 (3-133), P ≤ 0.002].

CONCLUSIONS

In patients with liver cirrhosis a urine protein:creatinine ratio >30 predicts AKI. Iohexol clearance and cystatin C formulae identify a greater proportion of patients with a GFR <60 mL/min/1.73 m(2), which also predicts the development of AKI.