Liver failure after partial hepatic resection: definition, pathophysiology, risk factors and treatment

Defining Post Hepatectomy Liver Insufficiency: Where do We stand?

BACKGROUND

Post-hepatectomy liver failure (PHLF) is a major source of morbidity and mortality in patients undergoing liver resection. The aim of this review is to summarize the recent literature available on PHLF including its definition, predictive factors, preoperative risk assessment, severity grading, preventative measures, and management strategies.

METHODS

A systematic literature search was carried out with the search engines PubMed, Medline, and Cochrane Database using the keywords related to "liver failure", "posthepatectomy", and "hepatic resection".

RESULTS

Liver resection is a curative treatment of liver tumors. However, it leads to concurrent death and regeneration of the remaining hepatocytes. Factors related to the patient, liver parenchyma and the extent of surgery can inhibit regeneration leading to PHLF.

CONCLUSION

Given its resistance to treatment and the high postoperative mortality associated with PHLF, great effort has been put in to both accurately identify patients at high risk and to develop strategies that can help prevent its occurrence.

Intraoperative severe hypoglycemia indicative of post-hepatectomy liver failure

We present the first reported case of a patient with intraoperative hypoglycemia, with no predisposing factors, that was indicative of post-hepatectomy liver failure due to liver injury. A 56-year-old man was hospitalized to undergo left lateral segmentectomy, cholecystectomy and T-tube choledocholithotripsy due to calculi in the intrahepatic and common bile ducts. His medical history was unremarkable. Three hours after surgery initiation, his glucose level decreased from 84 mg/dL to below detectable levels. We infused 20 % dextrose repeatedly until his glucose level returned to within normal limits. His aspartate aminotransferase and alanine aminotransferase levels increased to over 10,000 IU/L, and his blood urea nitrogen and creatinine levels increased postoperatively. Thus, we diagnosed post-hepatectomy liver failure and hepatorenal syndrome and treated the patient conservatively. This case illustrates that, if no other causative factors for severe hypoglycemia occurring during liver resection are present, the anesthesiologist should predict post-hepatectomy liver failure due to liver injury and inform the surgeon in order to enable rapid evaluation and treatment.

Validation of a semiautomated liver segmentation method using CT for accurate volumetry

RATIONALE AND OBJECTIVES

To compare the repeatability and agreement of a semiautomated liver segmentation method with manual segmentation for assessment of total liver volume on CT (computed tomography).

MATERIALS AND METHODS

This retrospective, institutional review board-approved study was conducted in 41 subjects who underwent liver CT for preoperative planning. The major pathologies encountered were colorectal cancer metastases, benign liver lesions and hepatocellular carcinoma. This semiautomated segmentation method is based on variational interpolation and 3D minimal path-surface segmentation. Total and subsegmental liver volumes were segmented from contrast-enhanced CT images in venous phase. Two image analysts independently performed semiautomated segmentations and two other image analysts performed manual segmentations. Repeatability and agreement of both methods were evaluated with intraclass correlation coefficients (ICC) and Bland-Altman analysis. Interaction time was recorded for both methods.

RESULTS

Bland-Altman analysis revealed an intrareader agreement of -1 ± 27 mL (mean ± 1.96 standard deviation) with ICC of 0.999 (P < .001) for manual segmentation and 12 ± 97 mL with ICC of 0.991 (P < .001) for semiautomated segmentation. Bland-Altman analysis revealed an interreader agreement of -4 ± 22 mL with ICC of 0.999 (P < .001) for manual segmentation and 5 ± 98 mL with ICC of 0.991 (P < .001) for semiautomated segmentation. Intermethod agreement was found to be 3 ± 120 mL with ICC of 0.988 (P < .001). Mean interaction time was 34.3 ± 16.7 minutes for the manual method and 8.0 ± 1.2 minutes for the semiautomated method (P < .001).

CONCLUSIONS

A semiautomated segmentation method can substantially shorten interaction time while preserving a high repeatability and agreement with manual segmentation.

Ultrasound-guided percutaneous microwave ablation treatment of initial recurrent hepatocellular carcinoma after hepatic resection: long-term outcomes

This study aimed to evaluate the long-term outcomes after percutaneous microwave ablation (MWA) for patients with initial recurrent hepatocellular carcinoma (HCC) measuring ≤5 cm in diameter after hepatectomy. From May 2005 to December 2011, 89 patients with 116 initial recurrent HCCs after hepatectomy treated with percutaneous MWA were included in the study. One mo after MWA, the complete ablation rate was 91.0% (81/89). At 1, 3, 5 and 7 y, the respective overall and recurrence-free survival rates after percutaneous MWA were 73.3%, 53.7%, 39.6% and 17.3% and 58.5%, 26.4%, 22.0% and 11.0%. The cumulative incidence of local tumor progression (LTP) and the intra-hepatic distant recurrence (IDR)-free survival rates after MWA were 9.1%, 14.6%, 18.3% and 18.3% and 62.9%, 32.3%, 26.9% and 13.5% at 1, 3, 5 and 7 y, respectively. The multivariate analysis indicated that multiple tumors (p = 0.006), a poor Child-Pugh score (p = 0.003), serum α-fetoprotein (AFP) >100 ng/mL (p = 0.002), and MWA treatment failure (p = 0.000) were risk factors that significantly affected overall survival, and MWA treatment failure (p = 0.000) was a risk factor that significantly affected IDR-free survival. In conclusion, percutaneous MWA is an effective therapeutic technique for initial recurrent HCC measuring ≤5 cm in diameter after hepatectomy.

Complex Surgical Strategies to Improve Resectability in Borderline-Resectable Disease

Colorectal cancer is the third most common malignancy in the USA and continues to pose a significant epidemiologic problem, despite major advances in the treatment of patients with advanced disease. Up to 50 % of patients will develop metastatic disease at some point during the course of their disease, with the liver being the most common site of metastatic disease. In this review, we address the relatively poorly defined entity of borderline-resectable colorectal liver metastases. The workup and staging of borderline-resectable disease are discussed. We then discuss management strategies, including surgical techniques and medical therapies, which are currently utilized in order to improve resectability.

Post hepatectomy liver failure: concept of management

BACKGROUND

In literature, the reported mortality of posthepatectomy liver failure is <5 % and morbidity is 15-30 %. Around 3-8 % of patients develop liver failure after major hepatic resection.

OBJECTIVE

The objective of the study was to provide current definitions and managing posthepatectomy liver failure (PHLF) as per severity and ISGLS grading.

METHOD

A systemic search of pubmed indexed articles was done and relevant articles were selected to formulate latest guidelines for PHLF.

CONCLUSION

We were able to make an algorithm for standardizing management so as to identify and treat PHLF as early as possible.

Liver-to-spleen ratio as an index of chronic liver diseases and safety of hepatectomy: a pilot study

BACKGROUND

Hepatic failure is a main cause of death after hepatectomy. Accurate preoperative evaluation of functional liver reserve is the key to ensure safe resection. Studies have found that the spleen would gradually enlarge as chronic liver disease worsened. This study was designed to determine whether preoperative liver-to-spleen ratio (LSR) would be an indicator to evaluate severity of liver disease and predict safety of hepatectomy.

METHODS

The volumes of liver and spleen were evaluated on computed tomography scan in 67 patients who received partial hepatectomy. Preoperative LSR was calculated. Statistical analysis was conducted to examine the relationship between LSR and the degree of chronic liver disease. Ability of LSR to predict the safety of hepatectomy also was evaluated.

RESULTS

LSR had a negative correlation with the degree of chronic liver diseases (r = -0.606, P < 0.0001). LSR = 3.22 was the cutoff point for predicting posthepatectomy complications and inadequacy. AUC, sensitivity, and specificity for predicting posthepatectomy complications and inadequacy respectively were 0.830 (95 % confidence interval [CI] 0.715-0.950, P < 0.0001), 69.6, 93.2 %, and 0.863 (95 % CI 0.777-0.949, P < 0.0001), 68.8, 84.3 %. Multivariate analysis showed that LSR = 3.22 was the factor that affected both posthepatectomy complications and liver inadequacy.

CONCLUSIONS

Preoperative LSR score correlated well with the degree of chronic liver diseases, and it probably help us to improve the safety of hepatectomy.

Sarcopenia, obesity and sarcopenic obesity: effects on liver function and volume in patients scheduled for major liver resection

BACKGROUND

Sarcopenia, obesity and sarcopenic obesity have been linked to impaired outcome after liver surgery. Preoperative liver function of sarcopenic, obese and sarcopenic-obese patients might be reduced, possibly leading to more post-operative morbidity. The aim of this study was to explore whether liver function and volume were influenced by body composition in patients undergoing liver resection.

METHODS

In 2011 and 2012, all consecutive patients undergoing the methacetin breath liver function test were included. Liver volumetry and muscle mass analysis were performed using preoperative CT scans and Osirix(®) software. Muscle mass and body-fat% were calculated. Predefined cut-off values for sarcopenia and the top two body-fat% quintiles were used to identify sarcopenia and obesity, respectively. Histologic assessment of the resected liver gave insight in background liver disease.

RESULTS

A total number of 80 patients were included. Liver function and volume were comparable in sarcopenic(-obese) and non-sarcopenic(-obese) patients. Obese patients showed significantly reduced liver function [295 (95-508) vs. 358 (96-684) µg/kg/h, P = 0.018] and a trend towards larger liver size [1694 (1116-2685) vs. 1533 (869-2852) mL, P = 0.079] compared with non-obese patients. Weight (r = -0.40), body surface area (r = -0.32), estimated body-fat% (r = -0.43) and body mass index (r = -0.47) showed a weak but significant negative (all P < 0.05) correlation with liver function. Moreover, body-fat% was identified as an independent factor negatively affecting the liver function.

CONCLUSION

Sarcopenia and sarcopenic obesity did not seem to influence liver size and function negatively. However, obese patients had larger, although less functional, livers, indicating dissociation of liver function and volume in these patients.

Administration of antithrombin III attenuates posthepatectomy liver failure in hepatocellular carcinoma

BACKGROUND/AIMS

Coagulopathy can cause disseminated intravascular coagulation and posthepatectomy liver failure. Posthepatectomy liver failure predicts a poor prognosis after hepatectomy for hepatocellular carcinoma. Although antithrombin III reduces hypercoagulation, the impact of postoperative antithrombin III administration remains unknown. The aim of this study was to determine whether postoperative antithrombin III administration protects against the development of coagulation disorders.

METHODS

Data from 164 patients who received antithrombin III and 169 who did following curative hepatectomy for hepatocellular carcinoma were retrospectively collected and analyzed. To overcome bias due to different distributions of covariates for the two groups, a one-to-one match was created using propensity score analysis. After matching, patient outcomes were analyzed.

RESULTS

A multivariate analysis of the whole group revealed that antithrombin III activity of <50% on postoperative day 1 was an independent risk factor for posthepatectomy liver failure. After one-to-one matching, the rate of posthepatectomy liver failure was significantly lower in the AT-III-treated group than in the non-AT-III-treated group (16.3% (7/43) vs. 44.2% (19/43), p < 0.01).

CONCLUSIONS

Antithrombin III may attenuate posthepatectomy liver failure in hepatocellular carcinoma, possibly by suppressing coagulopathy.

Texture analysis of preoperative CT images for prediction of postoperative hepatic insufficiency: a preliminary study

BACKGROUND

Texture analysis is a promising method of analyzing imaging data to potentially enhance diagnostic capability. This approach involves automated measurement of pixel intensity variation that may offer further insight into disease progression than do standard imaging techniques alone. We postulated that postoperative liver insufficiency, a major source of morbidity and mortality, correlates with preoperative heterogeneous parenchymal enhancement that can be quantified with texture analysis of cross-sectional imaging.

STUDY DESIGN

A retrospective case-matched study (waiver of informed consent and HIPAA authorization, approved by the Institutional Review Board) was performed comparing patients who underwent major hepatic resection and developed liver insufficiency (n = 12) with a matched group of patients with no postoperative liver insufficiency (n = 24) by procedure, remnant volume, and year of procedure. Texture analysis (with gray-level co-occurrence matrices) was used to quantify the heterogeneity of liver parenchyma on preoperative CT scans. Statistical significance was evaluated using Wilcoxon's signed rank and Pearson's chi-square tests.

RESULTS

No statistically significant differences were found between study groups for preoperative patient demographics and clinical characteristics, with the exception of sex (p < 0.05). Two texture features differed significantly between the groups: correlation (linear dependency of gray levels on neighboring pixels) and entropy (randomness of brightness variation) (p < 0.05).

CONCLUSIONS

In this preliminary study, the texture of liver parenchyma on preoperative CT was significantly more varied, less symmetric, and less homogeneous in patients with postoperative liver insufficiency. Therefore, texture analysis has the potential to provide an additional means of preoperative risk stratification.

Influence of clinically significant portal hypertension on hepatectomy for hepatocellular carcinoma: a meta-analysis

BACKGROUND

Clinically significant portal hypertension (PHT) is considered as a contraindication for hepatectomy according to the guidelines of the European Association for Study of Liver and the American Association for Study of Liver Diseases. However, this issue remains controversial. Here we performed a meta- analysis to evaluate the impact of PHT on the results of hepatectomy for hepatocellular carcinoma (HCC).

METHODS

Cohort studies evaluating the impact of clinically significant PHT, defined as oesophageal varices and/ or splenomegaly associated with thrombocytopenia, on the results of hepatectomy for HCC were identified using a predefined search strategy. Summary risk ratios (RRs) and 95% confidence intervals (95% CIs) for PHT and outcomes after hepatectomy for HCC were calculated.

RESULTS

Seven cohort studies which including 574 cases with PHT and 1,354 cases without PHT were considered eligible for inclusion. The meta-analysis showed that, in all patients, pooled RRs of post-operative liver failure, post-operative ascites, peri-operative blood transfusion, operative mortality, 3- and 5-year overall survival associated with PHT were 2.23 (95% CI: 1.48-3.34, P=0.0001), 1.77 (95% CI: 1.19-2.64, P=0.005), 1.23 (95% CI: 1.03-1.49, P=0.03), 2.58 (95% CI: 1.12-5.96, P=0.03), 0.82 (95% CI: 0.75-0.88, P<0.00001) and 0.76 (95% CI: 0.69-0.85, P<0.00001), respectively. In subgroup analysis, similar results were found in Child-Pugh class A patients.

CONCLUSION

This meta-analysis suggests that presence of oesophageal varices and/or splenomegaly associated with thrombocytopenia is associated with higher rates of post-operative complications and poor long-term survival after hepatectomy for HCC.

Small for size liver remnant following resection: prevention and management

In the latest decades an important change was registered in liver surgery, however the management of liver cirrhosis or small size hepatic remnant still remains a challenge. Currently post-hepatectomy liver failure (PLF) is the major cause of death after liver resection often associated with sepsis and ischemia-reperfusion injury (IRI). ''Small-for-size'' syndrome (SFSS) and PFL have similar mechanism presenting reduction of liver mass and portal hyper flow beyond a certain threshold. Few methods are described to prevent both syndromes, in the preoperative, perioperative and postoperative stages. Additionally to portal vein embolization (PVE), radiological examinations (mainly CT and/or MRI), and more recently 3D computed tomography are fundamental to quantify the liver volume (LV) at a preoperative stage. During surgery, in order to limit parenchymal damage and optimize regenerative capacity, some hepatoprotective measures may be employed, among them: intermittent portal clamping and hypothermic liver preservation. Regarding the treatment, since PLF is a quite complex disease, it is required a multi-disciplinary approach, where it management must be undertaken in conjunction with critical care, hepatology, microbiology and radiology services. The size of the liver cannot be considered the main variable in the development of liver dysfunction after extended hepatectomies. Additional characteristics should be taken into account, such as: the future liver remnant; the portal blood flow and pressure and the exploration of the potential effects of regeneration preconditioning are all promising strategies that could help to expand the indications and increase the safety of liver surgery.

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.

Balloon venoplasty for liver failure due to stenosis of the left hepatic vein after right tri-segmentectomy

A 41-year-old male patient with hepatitis B underwent right tri-segmentectomy and total caudate lobectomy for a huge hepatocellular carcinoma associated with complete occlusion of the inferior vena cava with thrombosis of the infrahepatic inferior vena cava due to tumor compression. Five months later, he was readmitted for ascites and hyperbilirubinemia. Venography revealed stenosis and tortuosity of the left hepatic vein and the inferior vena cava, for which balloon angioplasty of the left hepatic vein and the inferior vena cava was performed using an 8-mm and 10-mm balloon, respectively. The left hepatic venous pressure decreased from 65 mmHg to 25 mmHg after dilatation. The patient made a satisfactory recovery thereafter and remains well with normal liver functions and without ascites. Balloon angioplasty may be useful for liver failure due to hepatic vein stenosis after hepatic resection.

New perspectives in the assessment of future remnant liver

In order to achieve microscopic radical resection margins and thus better survival, surgical treatment of hepatic tumors has become more aggressive in the last decades, resulting in an increased rate of complex and extended liver resections. Postoperative outcomes mainly depend on the size and quality of the future remnant liver (FRL). Liver resection, when performed in the absence of sufficient FRL, inevitably leads to postresection liver failure. The current gold standard in the preoperative assessment of the FRL is computed tomography volumetry. In addition to the volume of the liver remnant after resection, postoperative function of the liver remnant is directly related to the quality of liver parenchyma. The latter is mainly influenced by underlying diseases such as cirrhosis and steatosis, which are often inaccurately defined until microscopic examination after the resection. Postresection liver failure remains a point of major concern that calls for accurate methods of preoperative FRL assessment. A wide spectrum of tests has become available in the past years, attesting to the fact that the ideal methodology has yet to be defined. The aim of this review is to discuss the current modalities available and new perspectives in the assessment of FRL in patients scheduled for major liver resection.

Using Dynamic 99mT c-GSA SPECT/CT fusion images for hepatectomy planning and postoperative liver failure prediction

BACKGROUND

Available tools in liver surgery planning rely on the future remnant liver (FRL) volume. Inappropriate decision might be made since the same FRL volume might represent different liver functions depending on the severity of underlying liver damage. This study developed an alternative system to estimate FRL function and to predict the risk of postoperative liver failure.

METHODS

Current study recruited 71 prehepatectomy patients and 71 healthy volunteers. A technetium-99-labelled asialoglycoproteins was given to participants and SPECT was used to capture the intensity of the signal, represented by uptake index (UI). The agreement between preoperative UI values, liver function tests, and Child scores were evaluated. Linear regression was used to evaluate the agreement between predicted UI for FRL and postoperative UI values. Area under the receiver operating characteristic (AUC) curve was used to evaluate the discriminative performance of UI in differentiating patient with high risk of liver failure.

RESULTS

Preoperative UIs are highly correlated with Child score (P < 0.0001), especially to identify patients with ascites and elevated bilirubin. The predicted UIs were in close agreement with the actual postoperative UI values (r = 0.95 P < 0.001). The AUC analysis indicated that UI values had a high accuracy in predicting the risk of liver failure (AUC = 0.95, P < 0.0001). The best cut-off point was 0.9 and the corresponding sensitivity was 100 % and specificity was 92 %.

CONCLUSIONS

The new methodology reliably estimates FRL function and predicts the risk of liver failure. It provides a visual aid for liver surgeon in surgery planning and risk assessment.

The liver protective effect of methylprednisolone on a new experimental acute-on-chronic liver failure model in rats

BACKGROUND

Acute-on-chronic liver failure is a severe, life-threatening entity and the comprehension of this disease is incomplete. Currently, a reasonable surgical model of acute-on-chronic liver failure is still lacking. The aim of this study was to establish a new model of acute-on-chronic liver failure in rats and to investigate the protective effects of methylprednisolone on this model.

METHODS

An obstructive jaundice model in rats was established. Two weeks later, the animals were subjected to a choledochoduodenostomy and a reduced-size hepatic ischaemia/reperfusion injury. Animals were randomly divided into a control group, a methylprednisolone injected via the tail vein group and a methylprednisolone injected via the portal vein group. The survival rates and serum levels of alanine transaminase, aspartate aminotransferase, total bilirubin, tumour necrosis factor alpha, and interferon gamma of the rats were measured and the pathological changes in liver tissues were observed.

RESULTS

The survival rate was significantly improved in the methylprednisolone treatment groups. Serum levels of the biochemical indexes were the lowest in the portal vein injection group. Liver tissues under microscopy presented severe pathological injury in the control group.

CONCLUSION

This model could be useful for further research into acute-on-chronic liver failure and methylprednisolone may be a potential therapeutic agent for this disease.

Liver regeneration after liver resection: Clinical aspects and correlation with infective complications

AIM: To investigate whether early liver regeneration after resection in patients with hepatic tumors might be influenced by post-operative infective complications.

METHODS: A retrospective analysis of 27 liver resections for tumors performed in a single referral center from November 2004 to January 2010. Regeneration was evaluated by multidetector computed tomography at a mean follow-up of 43.85 d. The Clavien-Dindo classification was used to evaluate postoperative events in the first 6 mo after transplantation, and Centers for Disease Control and Prevention definitions were used for healthcare associated infections data. Generalized linear regression models with Gaussian family distribution and log link function were used to reveal the principal promoters of early liver regeneration.

RESULTS: Ten of the 27 patients (37%) underwent chemotherapy prior to surgery, with a statistically significant prevalence of patients with metastasis (P = 0.007). Eight patients (30%) underwent embolization, 3 with primary tumors, and 5 with secondary tumors. Twenty patients (74%) experienced complications, with 12 (60%) experiencing Clavien-Dindo Grade 3a to 5 complications. Regeneration ≥ 100% occurred in 10 (37%) patients. The predictors were smaller future remnant liver volume (-0.002; P < 0.001), and a greater spleen volume/future remnant liver volume ratio (0.499; P = 0.01). Patients with a resection of ≥ 5 Couinaud segments experienced greater early regeneration (P = 0.04). Nine patients experienced surgical site infections, and in 7 cases Clavien-Dindo Grade 3a to 4 complications were detected (P = 0.016). There were no significant differences between patients with primary or secondary tumors, and either onset or infections or severity of surgical complications.

CONCLUSION: Regardless of the onset of infective complications, future remnant liver and spleen volumes may be reliable predictors of early liver regeneration after hepatic resection on an otherwise healthy liver.

Liver stiffness value-based risk estimation of late recurrence after curative resection of hepatocellular carcinoma: development and validation of a predictive model

BACKGROUND

Preoperative liver stiffness (LS) measurement using transient elastography (TE) is useful for predicting late recurrence after curative resection of hepatocellular carcinoma (HCC). We developed and validated a novel LS value-based predictive model for late recurrence of HCC.

METHODS

Patients who were due to undergo curative resection of HCC between August 2006 and January 2010 were prospectively enrolled and TE was performed prior to operations by study protocol. The predictive model of late recurrence was constructed based on a multiple logistic regression model. Discrimination and calibration were used to validate the model.

RESULTS

Among a total of 139 patients who were finally analyzed, late recurrence occurred in 44 patients, with a median follow-up of 24.5 months (range, 12.4-68.1). We developed a predictive model for late recurrence of HCC using LS value, activity grade II-III, presence of multiple tumors, and indocyanine green retention rate at 15 min (ICG R15), which showed fairly good discrimination capability with an area under the receiver operating characteristic curve (AUROC) of 0.724 (95% confidence intervals [CIs], 0.632-0.816). In the validation, using a bootstrap method to assess discrimination, the AUROC remained largely unchanged between iterations, with an average AUROC of 0.722 (95% CIs, 0.718-0.724). When we plotted a calibration chart for predicted and observed risk of late recurrence, the predicted risk of late recurrence correlated well with observed risk, with a correlation coefficient of 0.873 (P<0.001).

CONCLUSION

A simple LS value-based predictive model could estimate the risk of late recurrence in patients who underwent curative resection of HCC.

Low-power laser irradiation fails to improve liver regeneration in elderly rats at 48 h after 70 % resection

The liver regeneration is an important clinical issue after major hepatectomies. Unfortunately, many organs (including the liver) exhibit age-related impairments regarding their regenerative capacity. Recent studies found that low-power laser irradiation (LPLI) has a stimulatory effect on the liver regeneration process. However, its effects in elderly remain unknown. Thus, this study aimed to investigate the main molecular mechanisms involved in liver regeneration of partially hepatectomized elderly rats exposed to LPLI. The effects of 15 min of LPLI (wavelength of 632.8 nm; fluence of 0.97 J/cm(2); total energy delivered of 3.6 J) were evaluated in hepatectomized elderly Wistar male rats. Afterwards, through immunoblotting approaches, the protein expression and phosphorylation levels of hepatocyte growth factor (HGF), Met, Akt and Erk 1/2 signaling pathways as well as the proliferating cell nuclear antigen (PCNA) were investigated. It was observed that LPLI was not able to improve liver regeneration in elderly rats as evidenced by the lack of improvement of HGF and PCNA protein expression or phosphorylation levels of Met, Akt and Erk 1/2 in the remnant livers. In sum, this study demonstrated that the main molecular pathway, i.e. HGF/Met → Akt and Erk 1/2 → PCNA, involved in the hepatic regeneration process was not improved by LPLI in elderly hepatectomized rats, which in turn rules out LPLI as an adjuvant therapy, as observed in this protocol of liver regeneration evaluation (i.e. at 48 h after 70 % resection), in elderly.

The safe minimally ischemic liver remnant for small-for-size syndrome in porcine hepatectomy

BACKGROUND

The minimal functional remnant liver mass or graft after an ischemic injury in hepatectomy or living donor liver transplantation (LDLT) is not clear. This study sought to determine the minimal remnant liver (MRL) size after 20 minutes hepatic inflow occlusion (HIO) and the maximal portal flow with which the liver remnant can sustain in a porcine model.

METHODS

Twenty pigs that underwent massive hepatectomy were randomly divided into 3 groups: 30% group, the remnant constituted about 30% of total liver volume (TLV); 35%+O group, the remnant constitute about 35% of TLV with 20 minutes HIO, and 30%+O group, the remnant constituted about 30% of TLV with 20 minutes of HIO. We evaluated survival rates, kinetic portal vein pressures (PVP), hemodynamics, hepatocyte metabolism, and injury.

RESULTS

The 14-day survival rate in the 30%+O group was significantly reduced compared with that of either the 30% group or the 35%+O group: l00% versus 28.6% versus 85.7% respectively (P = .009). The tissue, serum analyses, and PVP in the 30%+O group were significantly different compared with the measurements among the other groups (P < .05), revealing that the liver remnant in 30%+O group could not sustain more than 3 times baseline portal flow, whereas in 35%+O group it could sustain 2.8 times baseline portal flow.

CONCLUSIONS

Intraoperative ischemia can injure the sinusoidal endothelium, decreasing its ability to regulate portal hyperperfusion, causing less than 30% to 35% of TLV to show small-for-size syndrome or postoperative liver failure.

The critical value of remnant liver volume-to-body weight ratio to estimate posthepatectomy liver failure in cirrhotic patients

BACKGROUND

The extensive use of major hepatectomy for liver malignancies with cirrhosis increases the risk of posthepatectomy liver failure (PHLF), which is associated with a high frequency of postoperative complications, mortality, and an increased length of hospital stay. Remnant liver volume-to-body weight ratio (RLV-BWR) is more specific than the ratio of RLV-to-total liver volume (RLV-TLV) in predicting postoperative course after major hepatectomy in normal liver. Patients having normal liver with an anticipated RLV-BWR ≤0.5% are at considerable risk for hepatic dysfunction and postoperative mortality. In the present study, the critical value of RLV-BWR after liver resection in cirrhotic liver was investigated.

PATIENTS AND METHODS

Thirty one patients who underwent hepatectomy for hepatocellular carcinoma in one medical treatment unit of West China Hospital from September 2012 to December 2012 were retrospectively enrolled in study. Volumetric measurements of TLV using computed tomography were obtained before hepatectomy. PHLF was diagnosed by the "50-50 criteria." The influence of RLV-TLV and RLV-BWR on the occurrence of PHLF was investigated, and the critical value of RLV-BWR was concluded.

RESULTS

According to the occurrence of PHLF, the patients were retrospectively divided into PHLF group and non-PHLF group. There were no statistical differences of preoperative indicators between the two groups. The intraoperative indicators including the resected liver volume, RLV-TLV, and RLV-BWR were statistically significant (P < 0.05) between the two groups. The postoperative indicators including total bilirubin (TBIL), international normalized ratio, and peritoneal drainage fluid at the third and the fifth day after surgery were statistically significant (P < 0.05) between the two groups. Area under the receiver operating characteristic curve (ROC curve) predicted by RLV-BWR to the incidence of PHLF was 0.864 (P = 0.019) with 95% confidence interval (95% CI = 0.608-0.819), and the sensitivity and specialty rate were 70% and 95%, which were more than 50% and 70%, respectively. It suggested that the critical value of RLV-BWR (1.4%) had a certain predictive value on PHLF. Area under the receiver operating characteristic curve predicted by RLV-TLV to the incidence of PHLF was 0.568 (P = 0.628) with 95% confidence interval (95% CI = 0.376-0.747), and the sensitivity and specialty rate were 42.9% and 82.6%, respectively. The sensitivity (42.9%) <50% suggested that the critical value of RLV-TLR (51%) had a poor predictive value on PHLF. According to the curve critical value 1.4% of RLV-BWR, the patients were divided into RLV-BWR ≥1.4% group and RLV-BWR <1.4% group, and the incidence of PHLF between the two groups was statistically significant (P = 0.006).

CONCLUSIONS

RLV-BWR was more specific than RLV-TLV in predicting PHLF after major hepatectomy of cirrhotic liver. Patients with an anticipated RLV-BWR <1.4% are at considerable risk for PHLF.

Partial Preservation of Segment IV Confers No Benefit When Performing Extended Right Hepatectomy for Colorectal Liver Metastases

Introduction. Reducing the volume of resected liver parenchyma may lead to lower morbidity and mortality. The aim of this study was to determine whether partial preservation of segment IV leads to improved outcomes when undertaking extended right hepatectomy for colorectal liver metastases (CRLM). Materials and Methods. A retrospective analysis of patients undergoing right-sided hepatectomy for CRLM was performed. Rates of 90-day mortality and organ dysfunction were compared in 117 patients undergoing right hepatectomy (n = 85), partially extended right hepatectomy with preservation of part of segment IV (n = 20), and fully extended right hepatectomy (n = 12). Results. The 90-day mortality rate of those undergoing right hepatectomy (3/85) was similar to that of those undergoing extended right hepatectomy (0/12) (P = 1.000) but lower than that of those undergoing partially extended right hepatectomy (4/20) (P = 0.024). The rates of hepatic and renal dysfunction were similar between patients undergoing right hepatectomy, partially extended or extended hepatectomy. Discussion. Preservation of part of segment IV confers little clinical benefit when performing extended right hepatectomy for CRLM.

Lipid overloading during liver regeneration causes delayed hepatocyte DNA replication by increasing ER stress in mice with simple hepatic steatosis

BACKGROUND AND AIM

Impaired fatty liver regeneration has already been reported in many genetic modification models. However, in diet-induced simple hepatic steatosis, which showed similar phenotype with clinical pathology, whether liver regeneration is impaired or not remains unclear. In this study, we evaluated liver regeneration in mice with diet-induced simple hepatic steatosis, and focused on excess lipid accumulation occurring during liver regeneration.

METHODS

Mice were fed high fat diet (HFD) or control diet for 9-10 weeks. We analyzed intrahepatic lipid accumulation, DNA replication, and various signaling pathways including cell proliferation and ER stress during liver regeneration after partial hepatectomy. In addition, some of mice were pretreated with tauroursodeoxycholic acid (TUDCA), a chemical chaperone which alleviates ER stress, and then we estimated TUDCA effects on liver regeneration.

RESULTS

The peak of hepatocyte BrdU incorporation, the expression of proliferation cell nuclear antigen (PCNA) protein, and the expressions of cell cycle-related genes were observed in delayed time in HFD mice. The expression of phosphorylated Erk1/2 was also delayed in HFD mice. The amounts of liver triglyceride were at least twofold higher in HFD mice at each time point. Intrahepatic palmitic acid was increased especially in HFD mice. ER stress induced during liver regeneration was significantly higher in HFD mice. In HFD mice, pretreatment with TUDCA reduced ER stress and resulted in improvement of delayed liver regeneration.

CONCLUSION

In simple hepatic steatosis, lipid overloading occurring during liver regeneration might be caused ER stress and results in delayed hepatocyte DNA replication.

Preconditioning of the liver for efficient repopulation by primary hepatocyte transplants

The therapeutic potential of liver cell transplantation has been demonstrated in multiple clinical studies to correct hereditary metabolic or chronic liver diseases. However, there are several outstanding issues, which need to be investigated: most notably donor cell engraftment and the subsequent selective expansion of transplanted cells. This protocol describes the preconditioning of the liver in a dipeptidyl peptidase-IV (DPPIV(-))-deficient rat model of efficient repopulation utilizing a selective external beam irradiation technique combined with regional transient portal ischemia (RTPI). Irradiation of the host liver impairs endogenous cell division, and the subsequent RTPI constitutes a strongly proliferative stimulus. Transplanted cells benefit from this stimulus, whereas endogenous cells have no ability to respond, due to a reduction in the mitotic capacity of the host liver. As described here, an effective preparative regime for liver repopulation is external beam liver irradiation in the form of a single dose of 25 Gy applied to the whole organ followed (4 days later) by RTPI of the right liver lobes lasting 90 min. After 1 h of reperfusion, the donor hepatocytes may be transplanted directly into the spleen as implantation site for further redistribution into the portal system and liver. This preparative regime certainly has the potential to be implemented in the clinic, since neither toxins nor highly potent carcinogens are used.

Long-term outcomes after hepatic resection combined with radiofrequency ablation for initially unresectable multiple and bilobar liver malignancies

BACKGROUND

Hepatic resection (HRE) combined with radiofrequency ablation (RFA) offers a surgical option to a group of patients with multiple and bilobar liver malignancies who are traditionally unresectable for inadequate functional hepatic reserve. The aims of the present study were to assess the perioperative outcomes, recurrence, and long-term survival rates for patients treated with HRE plus RFA in the management of primary hepatocellular carcinoma (HCC) and metastatic liver cancer (MLC).

METHODS

Data from all consecutive patients with primary and secondary hepatic malignancies who were treated with HRE combined with RFA between 2007 and 2013 were prospectively collected and retrospectively reviewed.

RESULTS

A total of 112 patients, with 368 hepatic tumors underwent HRE combined with ultrasound-guided RFA, were included in the present study. There were 40 cases of HCC with 117 tumors and 72 cases of MLC with 251 metastases. Most cases of liver metastases originated from the gastrointestinal tract (44, 61.1%). Other uncommon lesions included breast cancer (5, 6.9%), pancreatic cancer (3, 4.2%), lung cancer (4, 5.6%), cholangiocarcinoma (4, 5.6%), and so on. The ablation success rates were 93.3% for HCC and 96.7% for MLC. The 1-, 2-, 3-, 4-, and 5-y overall recurrence rates were 52.5%, 59.5%, 72.3%, 75%, and 80% for the HCC group and 44.4%, 52.7%, 56.1%, 69.4%, and 77.8% for the MLC group, respectively. The 1-, 2-, 3-, 4-, and 5-y overall survival rates for the HCC patients were 67.5%, 50%, 32.5%, 22.5%, and 12.5% and for the MLC patients were 66.5%, 55.5%, 50%, 30.5%, and 19.4%, respectively. The corresponding recurrence-free survival rates for the HCC patients were 52.5%, 35%, 22.5%, 15%, and 10% and for the MLC patients were 58.3%, 41.6%, 23.6%, 16.9%, and 12.5%, respectively.

CONCLUSIONS

HRE combined with RFA provides an effective treatment approach for patients with primary and secondary liver malignancies who are initially unsuitable for radical resection, with high local tumor control rates and promising survival data.

Management of post-hepatectomy complications

Hepatic resection had an impressive growth over time. It has been widely performed for the treatment of various liver diseases, such as malignant tumors, benign tumors, calculi in the intrahepatic ducts, hydatid disease, and abscesses. Management of hepatic resection is challenging. Despite technical advances and high experience of liver resection of specialized centers, it is still burdened by relatively high rates of postoperative morbidity and mortality. Especially, complex resections are being increasingly performed in high risk and older patient population. Operation on the liver is especially challenging because of its unique anatomic architecture and because of its vital functions. Common post-hepatectomy complications include venous catheter-related infection, pleural effusion, incisional infection, pulmonary atelectasis or infection, ascites, subphrenic infection, urinary tract infection, intraperitoneal hemorrhage, gastrointestinal tract bleeding, biliary tract hemorrhage, coagulation disorders, bile leakage, and liver failure. These problems are closely related to surgical manipulations, anesthesia, preoperative evaluation and preparation, and postoperative observation and management. The safety profile of hepatectomy probably can be improved if the surgeons and medical staff involved have comprehensive knowledge of the expected complications and expertise in their management. This review article focuses on the major postoperative issues after hepatic resection and presents the current management.

Renal dysfunction is an independent risk factor for mortality after liver resection and the main determinant of outcome in posthepatectomy liver failure

Introduction. The aim of this study was to assess the interaction of liver and renal dysfunction as risk factors for mortality after liver resection. Materials and Methods. A retrospective analysis of 501 patients undergoing liver resection in a single unit was undertaken. Posthepatectomy liver failure (PHLF) was defined according to the International Study Group of Liver Surgery (ISGLS) definition (assessed on day 5) and renal dysfunction according to RIFLE criteria. 90-day mortality was recorded. Results. Twenty-three patients died within 90 days of surgery (4.6%). The lowest mortality occurred in patients without evidence of PHLF or renal dysfunction (2.7%). The mortality rate in patients with isolated PHLF or renal dysfunction was 20% compared to 45% in patients with both. Diabetes (P = 0.028), renal dysfunction (P = 0.030), and PHLF on day 5 (P = 0.011) were independent predictors of 90-day mortality. Discussion. PHLF and postoperative renal dysfunction are independent predictors of 90-day mortality following liver resection but the predictive value for mortality is significantly higher when failure of both organ systems occurs simultaneously.

Liver failure after major liver resection: risk assessment by using preoperative Gadoxetic acid-enhanced 3-T MR imaging

PURPOSE

To determine if gadoxetic acid-enhanced magnetic resonance (MR) imaging with measurement of relative liver enhancement (RLE) on hepatobiliary phase images can allow preoperative assessment of the risk of liver failure after major liver resection.

MATERIALS AND METHODS

The local institutional review committee approved this retrospective analysis and waived written informed consent. The study included 73 patients (39 men; median age, 64.4 years) who underwent gadoxetic acid-enhanced 3-T MR imaging before resection of three or more liver segments. RLE was calculated as the ratio of signal intensity measurements of the liver parenchyma before and 20 minutes after intravenous administration of gadoxetic acid. RLE was assessed in each liver segment and the mean value of all segments was used for analysis. Posthepatectomy liver failure was defined according to the "50-50 criteria" (ie, prothrombin time <50% and serum bilirubin >50 µmol/L on postoperative day 5) and the International Study Group of Liver Surgery (ISGLS) classification. The association of RLE and liver failure was tested with univariate and multivariate logistic regression analysis. In addition to RLE, the latter also included demographic, clinical, operative, and histologic variables.

RESULTS

Patients with liver failure according to the 50-50 criteria (n = 3) had significantly lower RLE (54.5%) than those without (125.6%) (P = .009). According to ISGLS criteria, RLE was 112.5% in patients with grade A liver failure (n = 20), 88.4% in patients with grade B (n = 7), 41.7% (n = 2) in patients with grade C, and 136.5% (P < .001) in those without liver failure. In a logistic regression analysis, RLE was inversely related to the probability of liver failure according to the 50-50 (P = .02) and ISGLS (P < .001) criteria. In a multivariate analysis, RLE was independently associated with a higher probability of liver failure according to ISGLS classification (P = .003).

CONCLUSION

Gadoxetic acid-enhanced MR imaging can help with the assessment of the risk for liver failure after major liver resection.

Feasibility of semiautomated MR volumetry using gadoxetic acid-enhanced MRI at hepatobiliary phase for living liver donors

PURPOSE

To assess the feasibility of semiautomated MR volumetry using gadoxetic acid-enhanced MRI at the hepatobiliary phase compared with manual CT volumetry.

METHODS

Forty potential live liver donor candidates who underwent MR and CT on the same day, were included in our study. Semiautomated MR volumetry was performed using gadoxetic acid-enhanced MRI at the hepatobiliary phase. We performed the quadratic MR image division for correction of the bias field inhomogeneity. With manual CT volumetry as the reference standard, we calculated the average volume measurement error of the semiautomated MR volumetry. We also calculated the mean of the number and time of the manual editing, edited volume, and total processing time.

RESULTS

The average volume measurement errors of the semiautomated MR volumetry were 2.35% ± 1.22%. The average values of the numbers of editing, operation times of manual editing, edited volumes, and total processing time for the semiautomated MR volumetry were 1.9 ± 0.6, 8.1 ± 2.7 s, 12.4 ± 8.8 mL, and 11.7 ± 2.9 s, respectively.

CONCLUSION

Semiautomated liver MR volumetry using hepatobiliary phase gadoxetic acid-enhanced MRI with the quadratic MR image division is a reliable, easy, and fast tool to measure liver volume in potential living liver donors.

Serum arterial lactate concentration predicts mortality and organ dysfunction following liver resection

BACKGROUND

The aim of this study was to determine if the post-operative serum arterial lactate concentration is associated with mortality, length of hospital stay or complications following hepatic resection.

METHODS

Serum lactate concentration was recorded at the end of liver resection in a consecutive series of 488 patients over a seven-year period. Liver function, coagulation and electrolyte tests were performed post-operatively. Renal dysfunction was defined as a creatinine rise of >1.5x the pre-operative value.

RESULTS

The median lactate was 2.8 mmol/L (0.6 to 16 mmol/L) and was elevated (≥2 mmol/L) in 72% of patients. The lactate concentration was associated with peak post-operative bilirubin, prothrombin time, renal dysfunction, length of hospital stay and 90-day mortality (P < 0.001). The 90-day mortality in patients with a post-operative lactate ≥6 mmol/L was 28% compared to 0.7% in those with lactate ≤2 mmol/L. Pre-operative diabetes, number of segments resected, the surgeon's assessment of liver parenchyma, blood loss and transfusion were independently associated with lactate concentration.

CONCLUSIONS

Initial post-operative lactate concentration is a useful predictor of outcome following hepatic resection. Patients with normal post-operative lactate are unlikely to suffer significant hepatic or renal dysfunction and may not require intensive monitoring or critical care.

A comparison of right posterior sectorectomy with formal right hepatectomy: a dual-institution study

OBJECTIVES

Right posterior sectorectomy (RPS) preserves liver volume but typically requires a longer parenchymal transection distance than does right hepatectomy (RH). This study was conducted to define the advantages of one approach over the other.

METHODS

Databases at two institutions were retrospectively reviewed for all patients submitted to RPS or RH between January 2000 and August 2012. Primary outcomes were perioperative complications and 90-day mortality.

RESULTS

Patients undergoing RPS (n = 100) and RH (n = 480), respectively, were similar in demographics, comorbidities, operative indications and Model for End-stage Liver Disease (MELD) mean scores (7.8 in the RPS group and 7.7 in the RH group; P = 0.49). A comparison of the RPS group with the RH group showed no significant differences in mean estimated blood loss (697 ml versus 713 ml; P = 0.900), rate of transfusions (19.2% versus 17.1%; P = 0.720), margin-positive resection (9.2% versus 11.6%; P = 0.70), complications (41.8% versus 42.0%; P = 1.000), bile leak (3.0% versus 4.0%; P = 1.000), or length of stay (7.5 days versus 8.3 days; P = 0.360). Postoperative hepatic insufficiency (defined as a postoperative bilirubin level of >7 mg/dl or significant ascites), occurred less frequently after RPS (1.0% versus 8.5%; P = 0.005). Operation type remained an independent determinant of postoperative hepatic insufficiency after controlling for preoperative risk factors (RH: hazard ratio = 9.628, 95% confidence interval 1.295-71.573; P = 0.027). A total of 28 (4.8%) patients died within 90 days; these included 25 (5.2%) patients in the RH group and three (3.0%) in the RPS group (P = 0.449).

CONCLUSIONS

Despite similar blood loss and overall morbidity, RPS is associated with less hepatic insufficiency than RH. Right posterior sectorectomy is parenchyma-sparing and should be strongly considered when it is technically feasible and oncologically sound.

Perioperative ischaemia-induced liver injury and protection strategies: An expanding horizon for anaesthesiologists

Liver resection is an effective modality of treatment in patients with primary liver tumour, metastases from colorectal cancers and selected benign hepatic diseases. Its aim is to resect the grossly visible tumour with clear margins and to ensure that the remnant liver mass has sufficient function which is adequate for survival. With the advent of better preoperative imaging, surgical techniques and perioperative management, there is an improvement in the outcome with decreased mortality. This decline in postoperative mortality after hepatic resection has encouraged surgeons for more radical liver resections, leaving behind smaller liver remnants in a bid to achieve curative surgeries. But despite advances in diagnostic, imaging and surgical techniques, postoperative liver dysfunction of varied severity including death due to liver failure is still a serious problem in such patients. Different surgical and non-surgical techniques like reducing perioperative blood loss and consequent decreased transfusions, vascular occlusion techniques (intermittent portal triad clamping and ischaemic preconditioning), administration of pharmacological agents (dextrose, intraoperative use of methylprednisolone, trimetazidine, ulinastatin and lignocaine) and inhaled anaesthetic agents (sevoflurane) and opioids (remifentanil) have demonstrated the potential benefit and minimised the adverse effects of surgery. In this article, the authors reviewed the surgical and non-surgical measures that could be adopted to minimise the risk of postoperative liver failure following liver surgeries with special emphasis on ischaemic and pharmacological preconditioning which can be easily adapted clinically.

N-acetylcysteine administration does not improve patient outcome after liver resection

BACKGROUND

Post-operative hepatic dysfunction is a major cause of concern when undertaking a liver resection. The generation of reactive oxygen species (ROS) as a result of hepatic ischaemia/reperfusion (I/R) injury can result in hepatocellular injury. Experimental evidence suggests that N-acetylcysteine may ameliorate ROS-mediated liver injury.

METHODS

A cohort of 44 patients who had undergone a liver resection and receiving peri-operative N-acetylcysteine (NAC) were compared with a further cohort of 44 patients who did not. Liver function tests were compared on post-operative days 1, 3 and 5. Peri-operative outcome data were retrieved from a prospectively maintained database within our unit.

RESULTS

Administration of NAC was associated with a prolonged prothrombin time on the third post-operative day (18.4 versus 16.4 s; P = 0.002). The incidence of grades B and C liver failure was lower in the NAC group although this difference did not reach statistical significance (6.9% versus 14%; P = 0.287). The overall complication rate was similar between groups (32% versus 25%; P = ns). There were two peri-operative deaths in the NAC group and one in the control group (P = NS).

CONCLUSION

In spite of promising experimental evidence, this study was not able to demonstrate any advantage in the routine administration of peri-operative NAC in patients undergoing a liver resection.

Physiological and biochemical basis of clinical liver function tests: a review

OBJECTIVE

To review the literature on the most clinically relevant and novel liver function tests used for the assessment of hepatic function before liver surgery.

BACKGROUND

Postoperative liver failure is the major cause of mortality and morbidity after partial liver resection and develops as a result of insufficient remnant liver function. Therefore, accurate preoperative assessment of the future remnant liver function is mandatory in the selection of candidates for safe partial liver resection.

METHODS

A MEDLINE search was performed using the key words "liver function tests," "functional studies in the liver," "compromised liver," "physiological basis," and "mechanistic background," with and without Boolean operators.

RESULTS

Passive liver function tests, including biochemical parameters and clinical grading systems, are not accurate enough in predicting outcome after liver surgery. Dynamic quantitative liver function tests, such as the indocyanine green test and galactose elimination capacity, are more accurate as they measure the elimination process of a substance that is cleared and/or metabolized almost exclusively by the liver. However, these tests only measure global liver function. Nuclear imaging techniques ((99m)Tc-galactosyl serum albumin scintigraphy and (99m)Tc-mebrofenin hepatobiliary scintigraphy) can measure both total and future remnant liver function and potentially identify patients at risk for postresectional liver failure.

CONCLUSIONS

Because of the complexity of liver function, one single test does not represent overall liver function. In addition to computed tomography volumetry, quantitative liver function tests should be used to determine whether a safe resection can be performed. Presently, (99m)Tc-mebrofenin hepatobiliary scintigraphy seems to be the most valuable quantitative liver function test, as it can measure multiple aspects of liver function in, specifically, the future remnant liver.

Kinetics of liver function tests after a hepatectomy for colorectal liver metastases predict post-operative liver failure as defined by the International Study Group for Liver Surgery

BACKGROUND

Post-hepatectomy liver failure (PHLF) has been defined by the International Study Group for Liver Surgery (ISGLS). The purpose of the present study was to examine the kinetics of conventional liver function tests (LFT) after a major liver resection and is the first to examine their utility in predicting PHLF in groups defined by the ISGLS.

METHODS

Consecutive patients undergoing a major liver resection for colorectal liver metastases were stratified into ISGLS groups and their LFT up to 1 year after surgery compared. Receiving-operating characteristic (ROC) analysis of LFT identified optimal thresholds in predicting category C liver failure.

RESULTS

In total, 32, 22 and 19 patients belonged to ISGLS groups A, B and C, respectively. The median international normalized ratio (INR) and bilirubin values on post-operative days 1, 3, 5 and 7 were significantly different among the groups (all P-values <0.05). ROC analysis of day 1 INR (AUC 0.813) and day 5 bilirubin (AUC 0.798) revealed thresholds of 1.35 and 52 μmol/l to have sensitivities of 85% and 81% and specificities of 63% and 73%, respectively, to predict group C liver failure.

DISCUSSION

Post-operative LFT after a major liver resection differs significantly among the three ISGLS groups. Thresholds of bilirubin and INR can be used to identify patients who are at a maximum risk of complications.

Effect of bone marrow mesenchymal stem cells on hepatocellular carcinoma in microcirculation

This study aims t explore the effect and application of bone marrow mesenchymal stem cells (BMSCs) on hepatocellular carcinoma in microcirculation by observing the angiogenesis of hepatocellular carcinoma in transplanted area. BMSCs were isolated and cultured primarily using the method of whole bone marrow culture and identifying surface antigens of third-generation bone marrow-derived mesenchymal stem cells using flow cytometry. Hepatoma cells cultured with BMSCs-conditioned medium (BMSCs-CM) were assayed using the cell proliferation rate of the MTT method. Nude mice were divided into control group (group A), BMSCs cell transplantation group (group B), HepG-2 cell group (group C), and combined BMSCs and HepG-2 cell cotransplanted group (group D). The result showed that the microvascular density was not significantly different in groups A and B. However, the microvascular density at 14 days was higher than 0 day in group C (P < 0.05). In group D, the microvascular density at 14 days was higher than that of 7 and 0 days (P < 0.05) and 7 days was higher than 0 days (P < 0.05). It was showed that the microvascular density did not get significant difference at 0 and 7 days in the four groups (P > 0.05). But the microvascular density of group C was higher than groups A and B at 14 days (P < 0.05), group D was higher than groups A and B at 14 days (P < 0.05) and group D was higher than group C at 14 days (P < 0.05). BMSCs could promote the growth of microvascular in hepatoma cells in a transplanted area.

Liver manipulation during liver surgery in humans is associated with hepatocellular damage and hepatic inflammation

BACKGROUND

Manipulation of the liver during liver surgery results in profound hepatocellular damage. Experimental data show that mobilization-induced hepatocellular damage is related to hepatic inflammation. To date, information on this link in humans is lacking. As it is possible to modulate inflammation, it is clinically relevant to unravel this relationship.

AIM

This observational study aimed to establish the association between liver mobilization and hepatic inflammation in humans.

METHODS

Consecutive patients requiring mobilization of the right hemi-liver during liver surgery were studied. Plasma samples and liver biopsies were collected prior to and directly after mobilization and after transection of the liver. Hepatocellular damage was assayed by liver fatty acid-binding protein (L-FABP) and aminotransferase levels. Hepatic inflammation was determined by (a) immunohistochemical identification of myeloperoxidase (MPO) and CD68- positive cells and (b) hepatic gene expression of inflammatory and cell adhesion molecules (IL-1β, IL-6, IL-8, VCAM-1 and ICAM-1).

RESULTS

A total of 25 patients were included. L-FABP levels increased significantly during mobilization (301 ± 94 ng/ml to 1599 ± 362 ng/ml, P = 0.008), as did ALAT levels (36 ± 5 IU/L to 167 ± 21 IU/L, P < 0.001). A significant increase in MPO (P = 0.001) and CD68 (P = 0.002) positive cells was noticed in the liver after mobilization. The number of MPO-positive cells correlated with the duration of mobilization (Pearson correlation=0.505, P = 0.033). Hepatic gene expression of pro-inflammatory cytokines IL-1β and IL-6, chemo-attractant IL-8 and adhesion molecule ICAM-1 increased significantly during liver manipulation.

CONCLUSIONS

Liver mobilization is associated with hepatocellular damage and liver inflammation, as shown by infiltration of inflammatory cells and upregulation of genes involved in acute inflammation.

Acute Liver Failure following Hepatic Resection: Incidence, Presentation, Prevention and Management in ICU

The incidence of liver failure following liver resection has been reported to be between 8–32%, depending on the number of segments resected, the health of the patient and the incidence of hepatic ischaemic/reperfusion injury. This article outlines the evidence surrounding classification, prevention and management of this condition.