Early identification of patients at increased risk for hepatic insufficiency, complications and mortality after major hepatectomy

Evaluation of liver regeneration after hemi-hepatectomy by combining computed tomography and post-operative liver function

Background

Accurate evaluation of postoperative liver regeneration is essential to prevent postoperative liver failure.

Aims

To analyze the predictors that affect liver regeneration after hemi-hepatectomy.

Method

Patients who underwent hemi-hepatectomy in Hangzhou First People's Hospital and Hangzhou Shulan Hospital from January 2016 to December 2021 were enrolled in this study. The regeneration index (RI) was calculated by the following equation: RI = [(postoperative total liver volume {TLVpost} - future liver remnant volume {FLRV}/FLRV] × 100 %. Hepatic dysfunction was defined according to the "TBilpeak>7" standard, which was interpreted as (peak) total bilirubin (TBil) >7.0 mg/dL. Good liver regeneration was defined solely when the RI surpassed the median with hepatic dysfunction. Logistic regression analyses were performed to estimate prognostic factors affecting liver regeneration.

Result

A total of 153 patients were enrolled, with 33 in the benign group and 120 patients in the malignant group. In the entire study population, FLRV% [OR 4.087 (1.405-11.889), P = 0.010], international normalized ratio (INR) [OR 2.763 (95%CI, 1.008-7.577), P = 0.048] and TBil [OR 2.592 (95%CI, 1.177-5.710), P = 0.018] were independent prognostic factors associated with liver regeneration. In the benign group, only the computed tomography (CT) parameter FLRV% [OR, 11.700 (95%CI, 1.265-108.200), P = 0.030] predicted regeneration. In the malignant group, parenchymal hepatic resection rate (PHRR%) [OR 0.141 (95%CI, 0.040-0.499), P = 0.002] and TBil [OR 3.384 (95%CI, 1.377-8.319), P = 0.008] were independent prognostic factors.

Conclusion

FLRV%, PHRR%, TBil and INR were predictive factors associated with liver regeneration.

Association of Viral Hepatitis Status and Post-hepatectomy Outcomes in the Era of Direct-Acting Antivirals

BACKGROUND

The role of viral hepatitis status in post-hepatectomy outcomes has yet to be delineated. This large, multicentred contemporary study aimed to evaluate the effect of viral hepatitis status on 30-day post-hepatectomy complications in patients treated for hepatocellular carcinoma (HCC).

METHODS

Patients from the National Surgical Quality Improvement Program (NSQIP) database with known viral hepatitis status, who underwent hepatectomy for HCC between 2014 and 2018, were included. Patients were classified as HBV-only, HCV-only, HBV and HCV co-infection (HBV/HCV), or no viral hepatitis (NV). Multivariable models were used to assess outcomes of interest. The primary outcome was any 30-day post-hepatectomy complication. The secondary outcomes were major complications and post-hepatectomy liver failure (PHLF). Subgroup analyses were performed for cirrhotic and noncirrhotic patients.

RESULTS

A total of 3234 patients were included. The 30-day complication rate was 207/663 (31.2%) HBV, 356/1077 (33.1%) HCV, 29/81 (35.8%) HBV/HCV, and 534/1413 (37.8%) NV (p = 0.01). On adjusted analysis, viral hepatitis status was not associated with occurrence of any 30-day post-hepatectomy complications (ref: NV, HBV odds ratio (OR) 0.89 [95% confidence interval (CI): 0.71-1.12]; HCV OR 0.91 [95% CI: 0.75-1.10]; HBV/HCV OR 1.17 [95% CI: 0.71-1.93]). Similar results were found in cirrhotic and noncirrhotic subgroups, and for secondary outcomes: occurrence of any major complications and PHLF.

CONCLUSIONS

In patients with HCC managed with resection, viral hepatitis status is not associated with 30-day post-hepatectomy complications, major complications, or PHLF compared with NV. This suggests that clinical decisions and prognostication of 30-day outcomes in this population likely should not be made based on viral hepatitis status.

Development of an Integer-based Risk Score to Predict 90-Day Mortality After Hepatectomy in Patients With Hepatocellular Carcinoma

BACKGROUND

The incidence of liver cancer has more than tripled since 1980. Hepatectomy represents the major curative treatment for liver cancer. The risk factors associated with 90-day mortality after hepatectomy are not well understood and there are currently no good prediction models for this outcome. The objectives of the current study were to identify risk factors of 90-day mortality after hepatectomy in patients with hepatocellular carcinoma and to develop an integer-based risk score using the National Cancer Database.

METHODS

Hepatectomies recorded in the National Cancer Database during 2004-2012 were reviewed for 90-day mortality. Risk factors were identified by multivariate logistic regression models. An integer-based risk score was developed using the β coefficients derived from the logistic regression model and tested for discriminatory ability. According to the total risk score, patients were grouped into 4 risk groups.

RESULTS

The overall 90-day mortality was 10.2%. Ten risk factors were identified, which included sex, age, race/ethnicity, insurance status, education, annual hospital volume, stage, tumor grade, Charlson-Deyo Score, and surgical procedure. The risk of 90-day mortality was stratified into 4 groups. The calculated 90-day mortality rates were 2.47%, 5.88%, 12.58%, and 24.67% for low-risk, medium-risk, high-risk, and excessive-risk groups, respectively. An area under the receiver operating characteristic curve of 0.69 was obtained for model discrimination.

CONCLUSIONS

The integer-based risk score we developed could easily quantify each patient's risk level and predict 90-day mortality after hepatectomy. The stratified risk score could be a useful addition to perioperative risk management and a tool to improve 90-day mortality after hepatectomy.

Model-inferred mechanisms of liver function from magnetic resonance imaging data: Validation and variation across a clinically relevant cohort

Estimation of liver function is important to monitor progression of chronic liver disease (CLD). A promising method is magnetic resonance imaging (MRI) combined with gadoxetate, a liver-specific contrast agent. For this method, we have previously developed a model for an average healthy human. Herein, we extended this model, by combining it with a patient-specific non-linear mixed-effects modeling framework. We validated the model by recruiting 100 patients with CLD of varying severity and etiologies. The model explained all MRI data and adequately predicted both timepoints saved for validation and gadoxetate concentrations in both plasma and biopsies. The validated model provides a new and deeper look into how the mechanisms of liver function vary across a wide variety of liver diseases. The basic mechanisms remain the same, but increasing fibrosis reduces uptake and increases excretion of gadoxetate. These mechanisms are shared across many liver functions and can now be estimated from standard clinical images.

Being able to accurately and reliably estimate liver function is important when monitoring the progression of patients with liver disease, as well as when identifying drug-induced liver injury during drug development. A promising method for quantifying liver function is to use magnetic resonance imaging combined with gadoxetate. Gadoxetate is a liver-specific contrast agent, which is taken up by the hepatocytes and excreted into the bile. We have previously developed a mechanistic model for gadoxetate dynamics using averaged data from healthy volunteers. In this work, we extended our model with a non-linear mixed-effects modeling framework to give patient-specific estimates of the gadoxetate transport-rates. We validated the model by recruiting 100 patients with liver disease, covering a range of severity and etiologies. All patients underwent an MRI-examination and provided both blood and liver biopsies. Our validated model provides a new and deeper look into how the mechanisms of liver function varies across a wide variety of liver diseases. The basic mechanisms remain the same, but increasing fibrosis reduces uptake and increases excretion of gadoxetate.

Treatment of metastatic colorectal cancer: innovations in surgical techniques

Liver metastases and peritoneal carcinomatosis are a particular focus of surgeons in improving survival in stage IV colorectal cancer patients, with laparotomy long being the means to undertake these operations. The Louisville statement published in 2008 was the first international consensus on indications for minimally invasive liver resection. Herein we review the progress in innovative surgical techniques, including minimally invasive liver resection, robot-assisted hepatectomy, and we also describe initial reports in pressurized intraperitoneal aerosol chemotherapy.

Effects of hepatic blood inflow on liver ultrastructure and regeneration after extensive liver resection in rats with cirrhosis

The aim of the present study was to investigate the effects of hepatic blood inflow on liver function, liver ultrastructure and the regeneration of future liver remnant (FLR) following major hepatectomy in rats with liver cirrhosis. A rat model of cirrhosis was established through intraperitoneal injection of carbon tetrachloride for 8 consecutive weeks. Extensive liver resection and different blood inflow models by portal vein (PV) and/or hepatic artery (HA) stenosis were conducted on the cirrhosis rats. Animal models were constructed as follows: Control (group A), low-flow PV + high-flow HA (group B), low-flow PV + low-flow HA (group C), high-flow PV + high-flow HA (group D) and high-flow PV + low-flow HA (group E). Hepatic blood inflow was detected by laser speckle contrast analysis, liver function and pathological changes were analyzed, Masson staining was used to identify the fibrosis of the liver and Periodic acid-Schiff staining was used to identify glycogen synthesis and hepatocyte function. The liver cell ultrastructure was evaluated by transmission electron microscopy, and the expression of Ki-67 in hepatocytes and the weight of the FLR were recorded to determine the regeneration of the FLR. Five days after major hepatectomy and liver blood inflow modulation, pathological examination of the livers from groups B and C revealed less congestion and less extensive hepatocellular injury. The serum alanine aminotransferase level of group B at 1, 3 and 5 days after hepatectomy and blood inflow modulation was 460.9±31.7, 331.0±22.0 and 285.6±15.8 U/l, respectively (control group: 676.9±41.7, 574.9±28.0 and 436.1±32.7 U/l, respectively; P<0.05); the total bilirubin of group B at 1, 3 and 5 days was 20.4±1.5, 16.1±1.0 and 13.5±0.6 µmol/l, respectively (control group: 30.3±1.4, 26.5±0.8 and 22.1±1.2 µmol/l, respectively; P<0.05). The size of the endoplasmic reticulum in the low-flow PV groups increased significantly and the mitochondrial swelling was alleviated. The positive rate of Ki-67 in the hepatocytes of groups B, C and D was 23.9±3.6, 15.7±2.3 and 12.9±2.4%, respectively (control group: 10.1±2.1%, P<0.05), and the positive rate of Ki-67 in group E was 6.1±1.4% (compared with that of the control group, P<0.05). The remnant liver weight of group B was 15.4±1.0 g (compared with that of the control group, P<0.05). Therefore, decreased portal blood flow combined with increased hepatic arterial blood flow alleviated the congestion in the liver following major hepatectomy in cirrhotic rats, improved the pathological status and liver function, increased the expression of Ki-67 and promoted liver regeneration.

Prospective evaluation of the International Study Group for Liver Surgery definition of post hepatectomy liver failure after liver resection: an international multicentre study

BACKGROUND

The International Study Group for Liver Surgery (ISGLS) definition of post hepatectomy liver failure (PHLF) was developed to be consistent, widely applicable, and to include severity stratification. This international multicentre collaborative study aimed to prospectively validate the ISGLS definition of PHLF.

METHODS

11 HPB centres from 7 countries developed a standardised reporting form. Prospectively acquired anonymised data on liver resections performed between 01 July 2010 and 30 June 2011 was collected. A multivariate analysis was undertaken of clinically important variables.

RESULTS

Of the 949 patients included, 86 (9%) met PHLF requirements. On multivariate analyses, age ≥70 years, pre-operative chemotherapy, steatosis, resection of >3 segments, vascular reconstruction and intraoperative blood loss >300 ml significantly increased the risk of PHLF. Receiver operator curve (ROC) analysis of INR and serum bilirubin relationship with PHLF demonstrated post-operative day 3 and 5 INR performed equally in predicting PHLF, and day 5 bilirubin was the strongest predictor of PHLF. Combining ISGLS grades B and C groups resulted in a high sensitivity for predicting mortality compared to the 50-50 rule and Peak bilirubin >7 mg/dl.

CONCLUSIONS

The ISGLS definition performed well in this prospective validation study, and may be the optimal definition for PHLF in future research to allow for comparability of data.

Perioperative Liver Function after Hepatectomy in a Tertiary University Hospital in Damascus

Background:

Liver resection is the only viable therapeutic treatment option for several neoplastic entities of the liver. Although, the number of resectable patients is increasing in Syria, liver failure is still a major complication affecting mortality and morbidity rates.

Methods:

Between 2009 and 2016, 104 patients undergoing liver resection in Damascus University Faculty of Medicine were retrospectively analyzed. Liver function tests were conducted before surgery (ps) and in the perioperative period (po) and comparisons were performed with division into anatomic VS non-anatomic or malignant VS non-malignant groups.

Results:

Liver synthetic, excretory and detoxifying functions deteriorated after liver resection (INR ps ‘presurgery’=1.129 po ‘perioperative’=1.426 P<0.001, TP ps=7.426 po=5.581 P<0.001, ALB ps=4.204 po=3.242 P<0.001, T-Bill ps=0.061 po=0.136 P<0.001) and liver cell necrosis increased after resection (ALT ps=27.597 po=200.221 P<0.001, AST ps=33.395 po=190.553 P<0.001). There was no significant difference in liver functions when we compared anatomic VS non-anatomic groups or malignant VS non-malignant groups, but liver cell necrosis was higher with malignancies (ALT malignant group=236.475 non-malignant group=89.5 P=0.002, AST malignant group=222.644 non-malignant group=101.125 P=0.001).

Conclusion:

Although liver resection affects liver function significantly, no differences in outcomes were found between anatomic VS non anatomic or malignant VS non-malignant groups.

Effect of obeticholic acid on liver regeneration following portal vein embolization in an experimental model

Background

The bile salt-activated transcription factor farnesoid X receptor (FXR) is a key mediator of proliferative bile salt signalling, which is assumed to play a role in the early phase of compensatory liver growth. The aim of this study was to evaluate the effect of a potent FXR agonist (obeticholic acid, OCA) on liver growth following portal vein embolization (PVE).

Methods

Rabbits were allocated to receive daily oral gavage with OCA (10 mg/kg) or vehicle (control group) starting 7 days before PVE (n = 18 per group), and continued until 7 days after PVE. PVE of the cranial liver lobes was performed using polyvinyl alcohol particles and coils on day 0. Caudal liver volume (CLV) was analysed by CT volumetry on days –7, –1, +3 and +7. Liver function was determined by measuring mebrofenin uptake using hepatobiliary scintigraphy. Additional parameters analysed were plasma aminotransferase levels, and histological scoring of haematoxylin and eosin- and Ki-67-stained liver sections.

Results

Three days after PVE of the cranial lobes, the increase in CLV was 2·2-fold greater in the OCA group than in controls (mean(s.d.) 56·1(20·3) versus 26·1(15·4) per cent respectively; P &lt; 0·001). This increase remained greater 7 days after PVE (+1·5-fold; P = 0·020). The increase in caudal liver function at day +3 was greater in OCA-treated animals (+1·2-fold; P = 0·017). The number of Ki-67-positive hepatocytes was 1·6-fold higher in OCA-treated animals 3 days after PVE (P = 0·045). Plasma aminotransferase levels and histology did not differ significantly between groups.

Conclusion

OCA accelerated liver regeneration after PVE in a rabbit model. OCA treatment might increase the efficacy of PVE and, thereby, resectability.

Minimally Invasive Surgery of the Liver

Operations on the liver have been undertaken for centuries for numerous indications including trauma, infections, and even for malignancy, but it was not until the past few decades that rates dramatically increased. This expanse in liver operations is due to a multitude of factors, including broader indications as well as improved safety. Our understanding of metastatic disease to the liver, especially colorectal cancer metastases, has vastly amplified the number of patients who would be candidates for hepatic resections and liver-directed therapies. We will focus our discussion here on planned minimally invasive operations for benign and malignant tumors as the majority of the literature relates to this setting.

Complications following hepatectomy

As the number of liver resections in the United States has increased, operations are more commonly performed on older patients with multiple comorbidities. The advent of effective chemotherapy and techniques such as portal vein embolization, have compounded the number of increasingly complex resections taking up to 75% of healthy livers. Four potentially devastating complications of liver resection include postoperative hemorrhage, venous thromboembolism, bile leak, and post-hepatectomy liver failure. The risk factors and management of these complications are herein explored, stressing the importance of identifying preoperative factors that can decrease the risk for these potentially fatal complications.