Evaluation of liver function for hepatic resection

Comparing iodized oil with polyvinyl alcohol for portal vein embolization in promoting liver remnant increase before partial hepatectomy

BACKGROUND

To compare the efficacy and safety of iodized oil versus polyvinyl alcohol (PVA) particles in portal vein embolization (PVE) before partial hepatectomy.

METHODS

From October 2016 to December 2021, 86 patients who planned to undergo hepatectomy after PVE were enrolled, including 61 patients post-PVE with PVA particles + coils and 25 patients post-PVE with iodized oil + coils. All patients underwent CT examination before and 2-3 weeks after PVE to evaluate the future liver remnant (FLR). The intercohort comparison included the degree of liver volume growth, changes in laboratory data, and adverse events.

RESULTS

There was no significant difference in the resection rate between the iodized oil group and the PVA particle group (68 % vs. 70 %, p = 0.822). In terms of the degree of hypertrophy (9.52 % ± 13.47 vs. 4.03 % ± 10.55, p = 0.047) and kinetic growth rate (4.07 % ± 5.4 vs. 1.55 % ± 4.63, p = 0.032), the iodized oil group was superior to the PVA group. The PVE operation time in the PVA particle group was shorter than that in the iodized oil group (121. 72 min ± 34.45 vs. 156. 2 min ± 71.58, p = 0.029). There was no significant difference in the degree of hypertrophy between the high bilirubin group and the control group (5.32 % ± 9.21 vs. 6.1 % ± 14.79, p = 0.764). Only 1 patient had a major complication.

CONCLUSIONS

Compared with PVA particles, iodized oil PVE can significantly increase liver volume and the degree of hypertrophy without any significant difference in safety.

Application of associating liver partition and portal vein ligation for staged hepatectomy for initially unresectable hepatocellular carcinoma

OBJECTIVE

To evaluate the safety and efficacy of associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) in the treatment of initially unresectable hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC) and to preliminarily explore the mechanism of rapid growth of the future liver remnant (FLR).

METHODS

Twenty-four patients with HBV-associated HCC who underwent ALPPS in our hospital from August 2014 to January 2021 were retrospectively studied. Propensity score matching was used to compare oncologic outcomes of patients treated with ALPPS and transarterial chemoembolization (TACE). The expression of YAP and JNK in liver tissue after two stages of ALPPS were detected.

RESULTS

The median standard liver volume (SLV) was 1471.4 ml. Before second stage of ALPPS, the median FLR increased by 74.4%, and the median FLR/SLV increased from 26.1 to 41.6%. Twenty-two patients (91.7%) received staged hepatectomy after a median interval of 15 (9-24) d. The total incidence of postoperative complications in ALPPS group was 54.5%, and of Clavien-Dindo ≥ IIIb postoperative complications (requiring surgical, endoscopic or radiological intervention under general anesthesia) was 9.1%. There was no significant difference in total complications between ALPPS group and TACE group, but there were lower rate of above grade III complications in the TACE group than that in the ALPPS group. The incidence of complications was lower in laparoscopic-ALPPS than that in open surgery. In ALPPS group, the 1-year, 2-year and 5-year overall survival rate were respectively 71.4%, 33.3% and 4.8%. Interval time was an independent risk factor associated with overall survival rate. There was no significant difference in overall survival rate between ALPPS group and TACE group. For advanced HCC (BCLC stage B and C), ALPPS group was not superior to TACE group in overall survival rate. The expression of YAP and p-JNK in the residual liver tissue after second stage procedure was higher than that after first stage procedure, and the co-expression of YAP and p-JNK was observed in the residual liver tissue.

CONCLUSION

ALPPS is a safe and effective treatment for initially unresectable HBV-associated HCC. Laparoscopic technique might improve the effect of ALPPS. YAP and JNK pathway might take a role in rapid FLR increase in ALPPS procedure.

Influence of constant lightning on liver health: an experimental study

Light pollution has become a serious problem in many urbanized areas of the world. The impact of prolonged exposure to light and consequent disruption of natural circadian rhythms has significant health implications. The current study was undertaken to evaluate the effect of prolonged exposure to light, simulating urban light pollution, on liver health. In order to evaluate the effect of prolonged exposure to light, we examined the morphofunctional state, immunohistochemical and micromorphometric parameters of rat liver in normal conditions and following prolonged lighting exposure. Our results show that nocturnal light disruption triggers a cell death in the liver within 3 weeks (necrosis and apoptosis of hepatocytes) and stimulates a change in normal cellular karyometric parameters. At the same time, intracellular regeneration takes place within the organ, which manifests through hepatocyte hypertrophy. Under the influence of constant illumination, the circadian rhythms (CRs) of the size of hepatocytes and their nuclei are restructured, and the rhythm of the nuclear-cytoplasmic ratio is destroyed. The destruction of the CR of expression of p53 and Ki-67 also occurs against the background of the rearrangement of the daily rhythmicity of Per2 and Bmal1. The revealed changes in the morphofunctional state of the liver under the influence of light pollution indicate that a violation of normal illumination regimes is a potent factor leading to significant structural changes in the liver.

Safety and outcomes of pre-operative portal vein embolization using N-butyl cyanoacrylate (Glue) in hepatobiliary malignancies: A single center retrospective analysis

Aims and Objectives:

To evaluate the outcome of preoperative portal vein embolization (PVE) using N-butyl cyanoacrylate (NBCA) for change in future liver remnant (FLR) volume, biochemical changes, and procedure-related complications. The factors affecting FLR hypertrophy and the rate of resection was also evaluated for this cohort.

Materials and Methods:

From 2012 to 2017, PVE utilizing NBCA mixed with lipiodol (1:4) was performed using percutaneous approach in 28 patients with hepatobiliary malignancies with low FLR. All patients underwent volumetric computed tomography (CT) assessment before and at 3–5 weeks after PVE and total liver volume (TLV), FLR volume, and FLR/TLV ratio, changes in portal vein diameter and factors affecting FLR were evaluated. Complications and the resectability rate were recorded and analyzed.

Result:

PVE was successful in all 28 patients. The mean FLR increased by 52% ± 32% after PVE (P < 0.0001). The FLR/TLV ratio was increased by 14.2% ± 2.8% (P < 0.001). Two major complications were encountered without any impact on surgery. There was no significant change seen in liver function test and complete blood counts after PVE. Eighteen patients (64.28%) underwent hepatic resection without any liver failure, and only three patients developed major complication after surgery. Remaining ten patients did not undergo surgery because of extrahepatic metastasis detected either on follow-up imaging or staging laparotomy. Patients with diabetes showed a lower rate of hypertrophy (P < 0.05).

Conclusion:

Preoperative PVE with NBCA is safe and effective for increasing FLR volume in patients of all age group and even in patients with an underlying liver parenchymal disease with hepatobiliary malignancy. Lesser hypertrophy was noted in patients with diabetes. A reasonable resectability was achieved despite having a high rejection in gall bladder cancer subgroup due to rapid disease progression.

Quantitative assessment of liver function with hepatocyte fraction: Comparison with T1 relaxation-based indices

PURPOSE

This study aimed to assess the use of hepatocyte fraction in gadoxetic acid-enhanced magnetic resonance imaging (MRI) for quantitatively evaluating the liver function in comparison with T1 relaxation-based indices.

METHODS

This retrospective study included 79 patients with chronic liver disease, who were divided into 2 groups based on the results of the indocyanine green retention test (ICG). All patients underwent a gadoxetic acid-enhanced MRI of the liver. Pre- and post-contrast Look-Locker sequences were used 20 min after gadoxetic acid administration to acquire T1 mapping. Two readers independently identified and measured the MRI parameters [five T1 relaxation-based indices (T1pre, T1post, rrT1, R1post/R1pre and ΔR1) and two hepatocyte fraction indices (HeF and K_Hep)]. An Independent-samples t test was used to compare each parameter for the two groups. Pearson correlation analysis was used to analyze the correction in each parameter and 15-minute ICG retention rate (ICG-R15). Receiver operating characteristic analyses were performed to differentiate the diagnostic performance of each parameter in ICG-R15 ≤ 20 % and ICG-R15 > 20 % groups.

RESULTS

T1pre and T1post were significantly lower in the ICG-R15 ≤ 20 % group than in the ICG-R15 > 20 % group (P < 0.05). rrT1, R1post/R1pre, ΔR1, HeF, and K_Hep were significantly higher in the ICG-R15 ≤ 20 % group than in the ICG-R15 > 20 % group (P < 0.05). The correction coefficients between T1pre, T1post, rrT1, R1post/R1pre, ΔR1, HeF, K_Hep, and ICG-R15 were 0.343, 0.783, -0.833, -0.781, -0.803, -0.819, and -0.832, respectively. The area under the curves (AUCs) of T1pre, T1post, rrT1, R1post/R1pre, ΔR1, HeF, and K_Hep in assessing the ICG-R15＞20 % groups were 0.761, 0.945, 0.912, 0.912, 0.948, 0.945, and 0.950, respectively. K_Hep had the highest AUC, sensitivity, and specificity.

CONCLUSION

Hepatocyte fraction based on gadoxetic acid-enhanced T1-mapping MRI is an efficient diagnostic tool for the quantitative evaluation of liver function.

[Role of the radiologist in surgery of colorectal liver metastases : What should be removed and what must remain]

BACKGROUND

The radical resection of colorectal liver metastases is the only curative option for affected patients. If properly performed, surgery provides the chance of long-term tumor-free survival.

OBJECTIVE

Summary of the critical interaction points between radiology and surgery in the planning and performance of (complex) liver resections.

RESULTS

There are many interaction points between radiology and surgery in the treatment of patients with colorectal liver metastases. Radiology supports surgery by providing detailed information of the localization of metastases, information on liver inflow and outflow as well as basic information on liver quality and function. Perioperatively, it provides interventional treatment options for postoperative complications as well as ablation of non-resectable metastases.

CONCLUSION

Complex liver resections can only be performed properly and successfully after thorough planning by an interdisciplinary board of surgeons, radiologists and associated disciplines.

Near-Infrared-Fluorescent Erythrocyte-Mimicking Particles: Physical and Optical Characteristics

Exogenous fluorescent materials activated by near-infrared (NIR) light can offer deep optical imaging with subcellular resolution, and enhanced image contrast. We have engineered NIR particles by doping hemoglobin-depleted erythrocyte ghosts (EGs) with indocyanine green (ICG). We refer to these optical particles as NIR erythrocyte-mimicking transducers (NETs). A particular feature of NETs is that their diameters can be tuned from micrometer to nanometer scale, thereby, providing a capability for broad NIR biomedical imaging applications. Herein, we investigate the effects of ICG concentration on key material properties of micrometer-sized NETs, and nanometer-sized NETs fabricated by either sonication or mechanical extrusion of EGs. The zeta potentials of NETs do not vary significantly with ICG concentration, suggesting that ICG is encapsulated within NETs regardless of particle size or ICG concentration. Loading efficiency of ICG into the NETs monotonically decreases with increasing values of ICG concentration. Based on quantitative analyses of the fluorescence emission spectra of the NETs, we determine that 20 μM ICG utilized during fabrication of NETs presents an optimal concentration that maximizes the integrated fluorescence emission for micrometer- and nanometer-sized NETs. Encapsulation of the ICG in these constructs also enhances the fluorescence stability and quantum yield of ICG. These results guide the engineering of NETs with maximal NIR emission for imaging applications such as fluorescence-guided tumor resection and real-time angiography.

Quantitative Assessment of Liver Function by Using Gadoxetic Acid-enhanced MRI: Hepatocyte Uptake Ratio

Purpose To determine whether hepatocyte uptake ratios derived at gadoxetic acid-enhanced MRI correlate with quantitative measures of liver function and can help to identify contraindication to major hepatectomy. Materials and Methods Between August 2016 and October 2016, 50 study participants with chronic liver disease or cirrhosis underwent liver MRI at 3.0 T including T1 mapping and elastography. Liver function was quantitatively assessed by using the indocyanine green retention test (ICG R₁₅). T1 maps were obtained by using the Look-Locker sequence before and 10 minutes after gadoxetic acid administration (0.025 mmol/kg). The relationship between ICG R₁₅ and the following MRI parameters was evaluated: pre- and postcontrast T1 values of the liver, hepatocyte uptake ratio representing the amount of contrast media solely taken into hepatocytes, liver volume, and degree of enhancement at the common bile duct. Diagnostic performance of the hepatocyte uptake ratio to identify patients with ICG R₁₅ greater than 20% (ie, contraindication to hepatectomy) was compared with other parameters by using areas under the receiver operating characteristic curve. Results Hepatocyte uptake ratio showed a negative correlation with ICG R₁₅ r of -0.78 (P < .001). In participants with chronic liver disease or Child-Pugh class A, those with ICG R₁₅ of 20% or less showed higher hepatocyte uptake ratio than those with ICG R₁₅ greater than 20% (P < .001). Hepatocyte uptake ratios demonstrated better performance for helping to detect ICG R₁₅ greater than 20% than did liver volume (area under the curve, 0.96 vs 0.70; P = .01). Conclusion Hepatocyte uptake ratios are negatively correlated with liver function as measured by indocyanine green retention test and provide acceptable diagnostic performance for helping to identify participants who have contraindications to major hepatectomy. © RSNA, 2018 Online supplemental material is available for this article. See also the editorial by Reeder in this issue.

Conversion therapy and suitable timing for subsequent salvage surgery for initially unresectable hepatocellular carcinoma: What is new?

AIM

To review the conversion therapy for initially unresectable hepatocellular carcinoma (HCC) patients and the suitable timing for subsequent salvage surgery.

METHODS

A PubMed search was undertaken from 1987 to 2017 to identify articles using the keywords including “unresectable” “hepatocellular carcinoma”, ”hepatectomy”, ”conversion therapy”, “resection”, “salvage surgery” and “downstaging”. Additional studies were investigated through a manual search of the references from the articles. The exclusion criteria were duplicates, case reports, case series, videos, contents unrelated to the topic, comments, and editorial essays. The main and widely used conversion therapies and the suitable timing for subsequent salvage surgery were discussed in detail. Two members of our group independently performed the literature search and data extraction.

RESULTS

Liver volume measurements [future liver remnant (FLR)/total liver volume or residual liver volume/bodyweight ratio] and function tests (scoring systems and liver stiffness) were often performed in order to justify whether patients were suitable candidates for surgery. Successful conversion therapy was usually defined as downstaging the tumor, increasing FLR and providing subsequent salvage surgery, without increasing complications, morbidity or mortality. The requirements for performing salvage surgery after transcatheter arterial chemoembolization were the achievement of a partial remission in radiology, the disappearance of the portal vein thrombosis, and the lack of extrahepatic metastasis. Patients with a standardized FLR (sFLR) > 20% were good candidates for surgery after portal vein embolization, while other predictive parameters like growth rate, kinetic growth rate were treated as an effective supplementary. There was probably not enough evidence to provide a standard operation time after associating liver partition and portal vein ligation for staged hepatectomy or yttrium-90 microsphere radioembolization. The indications of any combinations of conversion therapies and the subsequent salvage surgery time still need to be carefully and comprehensively evaluated.

CONCLUSION

Conversion therapy is recommended for the treatment of initially unresectable HCC, and the suitable subsequent salvage surgery time should be reappraised and is closely related to its previous therapeutic effect.

Assessing the Non-tumorous Liver: Implications for Patient Management and Surgical Therapy

INTRODUCTION

Hepatic resection is performed for various benign and malignant liver tumors. Over the last several decades, there have been improvements in the surgical technique and postoperative care of patients undergoing liver surgery. Despite this, liver failure following an extended hepatic resection remains a critical potential postoperative complication. Patients with underlying parenchymal liver diseases are at particular risk of liver failure due to impaired liver regeneration with an associated mortality risk as high as 60 to 90%. In addition, live donor liver transplantation requires a thorough presurgical assessment of the donor liver to minimize the risk of postoperative complications.

RESULTS AND CONCLUSION

Recently, cross-sectional imaging assessment of diffuse liver diseases has gained momentum due to its ability to provide both anatomical and functional assessments of normal and abnormal tissues. Various imaging techniques are being employed to assess diffuse liver diseases including magnetic resonance imaging (MRI), computed tomography (CT), and ultrasound (US). MRI has the ability to detect abnormal intracellular and molecular processes and tissue architecture. CT has a high spatial resolution, while US provides real-time imaging, is inexpensive, and readily available. We herein review current state-of-the-art techniques to assess the underlying non-tumorous liver. Specifically, we summarize current approaches to evaluating diffuse liver diseases including fatty liver alcoholic or non-alcoholic (NAFLD, AFLD), hepatic fibrosis (HF), and iron deposition (ID) with a focus on advanced imaging techniques for non-invasive assessment along with their implications for patient management. In addition, the role of and techniques to assess hepatic volume in hepatic surgery are discussed.

Resection for Klatskin tumors: technical complexities and results

Klatskin's tumors, actually-redefined as perihilar cholangiocarcinoma (phCCA) do represent 50-70% of all CCAs and develop in a context of chronic inflammation and cholestasis of bile ducts. Surgical resection provides the only chance of cure for this disease but is technically challenging because of the complex, intimate and variable relationship between biliary and vascular structures at this location. Five years survival rates range between 25-45% (median 27-58 months) in case of R0 resection and 0-23% (median 12-21 months) in case of R1 resection respectively. It should be noted that the major costs of high radicality are represented by relative high morbidity and mortality rates (i.e., 20-66% and 0-9% respectively). Considering the fact that radical resection may represent the only curative treatment of phCCA, we focused our review on surgical planning and techniques that may improve resectability rates and outcomes for locally advanced phCCA. The surgical treatment of phCCA can be successful when following aspects have been fulfilled: (I) accurate preoperative diagnostic aimed to identify the tumor in all its details (localization and extension) and to study all the risk factors influencing a posthepatectomy liver failure (PHLF): i.e., liver volume, liver function, liver quality, haemodynamics and patient characteristics; (II) High end surgical skills taking in consideration the local extension of the tumor and the vascular invasion which usually require an extended hepatic resection and often a vascular resection; (III) adequate postoperative management aimed to avoid major complications (i.e., PHLF and biliary complications). These are technically challenging operations and must be performed in a high volume centres by hepato-biliary-pancreas (HBP)-surgeons with experience in microsurgical vascular techniques.

Reversal of fibrosis in patients with nonalcoholic steatohepatosis after gastric bypass surgery

Background

Roux-en-Y gastric bypass (RYGB) improves the pathophysiology that contributes to obesity-related nonalcoholic steatohepatitis (NASH).

Whether obesity-related fibrosis improves is unclear. We hypothesized that RYGB reverses NASH and fibrosis, and indocyanine green (ICG) clearance provides a sensitive measure for detecting asymptomatic fatty liver disease.

Methods

One hundred six obese adults scheduled for RYGB had preoperative liver function assessed using standard tests and ICG clearance and core liver biopsies obtained during RYGB. Once patients lost 60% of their preoperative weight or weight loss plateaued, liver function was reassessed. Repeat liver biopsies were obtained on patients with NASH at the time of RYGB.

Results

RYGB improved steatosis, lobular inflammation, hepatocyte ballooning and fibrosis. Serum albumin, AST, and ALT decreased the most in patients with NASH and NASH plus fibrosis. Twenty seven (26%) patients had normal baseline liver histology and 45 (43%) had NASH or NASH plus fibrosis. Nine of 13 patients with substantial fatty liver had normalized histology after weight loss, while severity of disease in the rest had stabilized or was reduced. Mean ICG clearance in patients with normal/mild fatty liver disease and those with histological fatty livers did not differ significantly.

Conclusions

RYGB surgery reverses NASH and liver fibrosis. Underlying mechanisms that facilitate improvement remain unclear.

Intraoperative Real-Time Assessment of Liver Function with Near-Infrared Fluorescence Imaging

BACKGROUND

Postoperative liver failure is a serious complication after major hepatectomy, and perioperative prediction of its incidence using current technology is still very difficult. Near-infrared (NIR) fluorescence imaging allows quantitative assessment of the fluorescent signal from indocyanine green (ICG) in regions of interest on the liver surface. This method might offer a new promising modality for evaluating regional liver reserve. However, data are lacking regarding the relationship between liver function and fluorescent signals on the liver surface after intravenous ICG injection. This study was conducted to obtain the data necessary to apply NIR fluorescence imaging as a modality for measuring liver function.

MATERIALS AND METHODS

This study included 16 patients who underwent open hepatopancreatobiliary surgery between March 2011 and March 2012. After laparotomy, ICG was injected intravenously at 2.5 mg/L of liver volume, then the fluorescence intensity (FI) and signal-to-background ratio (SBR) in the lateral segment of the liver were assessed for 15 min. Intraoperative blood samples were also obtained to measure the plasma clearance rate of ICG (ICGK). Correlations between ICGK, liver volume, and SBR, as well as between ICGK, liver volume, and rate of change of FI were analyzed.

RESULTS

The experimental procedure was performed in all 16 patients. The FI of the liver increased rapidly after ICG injection, then became more gradual, reaching a near-plateau after 15 min. A significant correlation was seen between ICGK and the rate of change of FI up to 15 min (|rS| = 0.5725, p < 0.05).

CONCLUSION

This is the first report to show a relationship between liver function and fluorescent signals on the liver surface after intravenous ICG injection. Intraoperative NIR fluorescence imaging with ICG may be useful as a new method for assessing liver function.

CT volumetry of the liver: where does it stand in clinical practice?

Imaging-based volumetry has been increasingly utilised in current clinical practice to obtain accurate measurements of the liver volume. This is particularly useful prior to major hepatic resection and living donor liver transplantation where the size of the remnant liver and liver graft, respectively, affects procedural success and postoperative mortality and morbidity. The use of imaging-based volumetry, with emphasis on computed tomography, will be reviewed. We will explore the various technical factors that contribute to accurate volumetric measurements, and demonstrate how the accuracies of these techniques are influenced by their methodologies. The strengths and limitations of using anatomical imaging to estimate liver volume will be discussed, in relation to laboratory and functional imaging methods of assessment.

Portal vein embolization before right hepatectomy or extended right hepatectomy using sodium tetradecyl sulfate foam: technique and initial results

PURPOSE

To evaluate the safety and efficacy of portal vein embolization (PVE) with sodium tetradecyl sulfate (STS) foam.

MATERIALS AND METHODS

A single-center retrospective review of 35 patients (27 men and 8 women; mean age, 61 y) who underwent PVE with STS foam was performed. The technical success rate, rate of PVE at producing adequate future liver remnant (FLR) hypertrophy, and rate of disease progression precluding resection after PVE were analyzed. Complications of PVE and liver resection after PVE were recorded.

RESULTS

PVE was performed on 35 patients before right hepatic resection for both primary and secondary hepatic malignancies (22 hepatocellular carcinoma, 10 metastasis, 2 cholangiocarcinoma, 1 invasive gallbladder carcinoma). Technical success was achieved in 97.1% (34 of 35) of patients. Mean FLR of the total estimated liver volume increased from 24.5% (SD, 7.7%) to 36.5% (SD, 14.5%), a mean percentage increase of 48.8% (SD, 34.3%). PVE produced adequate FLR hypertrophy in 31 of 35 patients (88.6%). Proposed right hepatectomy was subsequently performed in 27 patients (77.1%). One patient remains scheduled for surgery, two had peritoneal spread at surgery and resection was aborted, two had disease progression on imaging after PVE, and three had inadequate FLR hypertrophy with no surgery. One major complication was observed related to PVE that involved nontarget embolization to segment III, which was managed conservatively.

CONCLUSIONS

Preoperative PVE with STS foam is a safe and effective method to induce hypertrophy of the FLR.

Sources of interindividual variability

The efficacy, safety, and tolerability of drugs are dependent on numerous factors that influence their disposition. A dose that is efficacious and safe for one individual may result in sub-therapeutic or toxic blood concentrations in other individuals. A major source of this variability in drug response is drug metabolism, where differences in pre-systemic and systemic biotransformation efficiency result in variable degrees of systemic exposure (e.g., AUC, C max, and/or C min) following administration of a fixed dose.Interindividual differences in drug biotransformation have been studied extensively. It is well recognized that both intrinsic (such as genetics, age, sex, and disease states) and extrinsic (such as diet, chemical exposures from the environment, and even sunlight) factors play a significant role. For the family of cytochrome P450 enzymes, the most critical of the drug metabolizing enzymes, genetic variation can result in the complete absence or enhanced expression of a functional enzyme. In addition, up- and down-regulation of gene expression, in response to an altered cellular environment, can achieve the same range of metabolic function (phenotype), but often in a less reliably predictable and time-dependent manner. Understanding the mechanistic basis for drug disposition and response variability is essential if we are to move beyond the era of empirical, trial-and-error dose selection and into an age of personalized medicine that brings with it true improvements in health outcomes in the therapeutic treatment of disease.

Serum albumin is present at higher levels in alcoholic liver cirrhosis as compared to HCV-related cirrhosis

Residual hepatic functional reserve in cirrhotic patients is generally evaluated by a multivariate scoring system (Child-Pugh classification), which includes serum albumin levels as a variable. However, several patients show discrepancies between serum albumin levels and the progression of liver fibrosis, especially those with alcoholic cirrhosis. To assess whether hepatic capacity of protein synthesis varies with the etiology of cirrhosis, serum albumin and cholinesterase levels, and prothrombin time were compared between alcoholic cirrhosis and hepatitis C virus (HCV)-related cirrhosis. To minimize the influence of malnutrition and extrahepatic platelet destruction, patients with hepatocellular carcinoma, uncontrolled diabetes, appetite loss and/or splenal longitudinal size >15 cm were excluded. The patients with compensated liver cirrhosis were divided into three groups as follows: alcohol(+)/HCV(+) (alcohol + HCV group; n=31), alcohol(-)/HCV(+) (HCV group; n=31) and alcohol(+)/HCV(-) (alcohol group; n=27). These groups were adjusted with respect to age, gender, body mass index and platelet count. Serum albumin levels in the alcohol group were significantly higher than those in the HCV group, with a difference of approximately 0.5 g/dl in every class of platelet count. The correlation of the alcohol + HCV group was intermediate between the alcohol and HCV groups. On the other hand, the correlations between serum cholinesterase levels and platelet counts were similar among the three groups. The prothrombin time was also comparable among the groups. Accordingly, serum albumin levels were higher in patients with alcoholic cirrhosis and alcohol consumption should be carefully considered when evaluating hepatic functional reserve.

The value of serum ischemia-modified albumin for assessing liver function in patients with chronic liver disease

BACKGROUND

Ischemia-modified albumin (IMA), measured by the cobalt-binding capacity of albumin, is a promising biomarker for cardiac ischemia. The IMA-to-serum albumin ratio (IMAR) has been reported to relate to the severity of decompensated liver cirrhosis. This study aimed to assess IMA and IMAR as a liver function test and to investigate whether albumin infusion changes IMAR in patients with liver cirrhosis.

METHODS

Blood samples were collected from healthy volunteers (n=51) and patients with chronic hepatitis (n=25), liver cirrhosis (n=24) and uremia (n=13). Parameters examined included serum levels of IMA, albumin, total bilirubin, creatinine, international normalized ratio (INR), model for end-stage liver disease (MELD) score, child-turcotte-pugh (CTP) score, indocyanine green (ICG) retention rate and total antioxidant capacity (TAC). Paired serum samples from patients pre- and post-albumin infusion (n=9) were collected and the changes were compared.

RESULTS

IMA and IMAR increased in patients with chronic hepatitis or cirrhosis, as compared to healthy volunteers. In patients with liver disease, IMA and IMAR were significantly associated with ICG retention, bilirubin, TAC and INR. In addition, IMAR was associated with CTP and MELD score in patients with cirrhosis. Albumin therapy improved patients' serum levels of creatinine and bilirubin and MELD score, but not IMA and IMAR.

CONCLUSIONS

IMAR, reflecting liver function and oxidative stress, is a more objective liver function test as it was not affected after a 3-day albumin infusion. More investigations, however, are needed to validate the use of IMAR in cases of chronic liver disease.

Correlation between liver functional reserve and hepatic fibrosis in patients with chronic liver disease

AIM: To investigate the correlation between liver functional reserve and hepatic fibrosis in patients with chronic liver disease.

METHODS: Sixty patients with chronic HBV infection were divided into two groups: patients with chronic hepatitis B and those with compensated cirrhosis. Indocyanine green (ICG) excretion test [plasma clearance (K) and retention rate at 15 min (R₁₅)] was conducted with the Pulse Dye Densitograph Analyzer (DDG). The degree of liver fibrosis was determined by FibroScan.

RESULTS: With the increase in the degree of liver fibrosis, K values decreased (184.786 ± 69.34 vs 93.826 ± 51.50, t = 5.216, P < 0.01) and R₁₅ values increased (9.536% ± 8.823% vs 30.304% ± 20.24%, t = 4.576, P < 0.01). A negative correlation was noted between K values and liver fibrosis scores (r = -0.712), while a positive correlation was observed between R15 values and liver fibrosis scores (r = 0.794).

CONCLUSION: Liver functional reserve decreases with the aggravation of liver fibrosis in patients with chronic liver disease.

Foam sclerotherapy using polidocanol (aethoxysklerol) for preoperative portal vein embolization in 16 patients

PURPOSE

To evaluate the clinical safety and effectiveness of foam sclerotherapy using polidocanol for preoperative portal vein embolization (PVE) before hemihepatectomy of the liver.

MATERIALS AND METHODS

From March 2006 to October 2008, foam sclerotherapy using polidocanol was performed in 16 patients (male-to-female ratio of 12:4, age range 48-75 years [mean 62]) for PVE. Patients were diagnosed with Klatskin tumor (n = 13), gallbladder (GB) cancer (n = 2), or hepatocellular carcinoma (HCC) (n = 1). The foam was composed of a 1:2:1 ratio of 3% polidocanol (Aethoxysklerol; Kreussler Pharma, Wiesbaden, Germany), room air, and contrast media (Xenetix 350; Guerbet, Aulnay-Sous-Bois, France). The total amount of polidocanol used (2 to 8 mL [mean 4.6]) varied according to the volume of the target portal vein. We calculated the volume of future liver remnant (FLR) before and after PVE and evaluated complications associated with the use of polidocanol foam sclerotherapy for PVE.

RESULTS

Technical success was achieved in all patients. All patients were comfortable throughout the procedure and did not experience pain during sclerotherapy. No periprocedural morbidity or mortality occurred. Patients underwent a liver dynamic computed tomography (CT) scan 2-4 weeks after PVE. FLR increased significantly after PVE using polidocanol foam from 19.3% (range 16-35%) before PVE to 27.8% (range 23-42%) after PVE (p = 0.001). All patients were operable for hemihepatectomy of the liver and achieved effective resection.

CONCLUSION

Foam sclerotherapy using polidocanol is clinically safe and effective for preoperative PVE.

Safety and efficacy of trisectionectomy for hepatocellular carcinoma

BACKGROUND

Right or left trisectionectomy represents the most extensive and difficult type of hepatic resection, and carries an unfavourably high morbidity and mortality. This retrospective study aimed to evaluate the safety and efficacy of trisectionectomy for hepatocellular carcinoma (HCC).

METHODS

From January 2000 to December 2008, 35 patients with HCC were treated with trisectionectomy. The treatment outcomes of these patients were retrospectively analysed.

RESULTS

Twenty-three right and 12 left trisectionectomies were performed. The overall operative morbidity and mortality were 42.8% (n= 15) and 2.8% (n= 1), respectively. The 1-, 3-, and 5-year overall survival rates were 82.9%, 51.4% and 23.8%, while the 1-, 3- and 5-year disease-free survival rates were 71.4%, 42.9% and 12.9%, respectively.

CONCLUSIONS

With careful patient selection and meticulous surgical technique, trisectionectomy can be performed safely and is associated with long-term survival in a subset of patients with HCC.

Virtual liver resection and volumetric analysis of the future liver remnant using open source image processing software

BACKGROUND

After extended liver resection, a remnant liver that is too small can lead to postresection liver failure. To reduce this risk, preoperative evaluation of the future liver remnant volume (FLRV) is critical. The open-source OsiriX PAC software system can be downloaded for free and used by nonradiologists to calculate liver volume using a stand-alone Apple computer. The purpose of this study was to assess the accuracy of OsiriX CT volumetry for predicting liver resection volume and FLVR in patients undergoing partial hepatectomy.

METHODS

Preoperative contrast-enhanced liver CT scans of patients who underwent partial hepatectomy were analyzed by three observers. Two surgical trainees measured the total liver volume, resection volume, and tumor volume using OsiriX, and a radiologist measured these volumes using CT scanner-linked Aquarius iNtuition software. Resection volume was correlated with prospectively determined resection weight, and differences in the measured liver volumes were analyzed. Interobserver variability was assessed using Bland-Altman plots.

RESULTS

25 patients (M/F ratio: 13/12) with a median age of 61 (range, 34-77) years were included. There were significant correlations between the weight and volume of the resected specimens (Pearson's correlation coefficient: R(2) = 0.95). There were no major differences in total liver volumes, resection volumes, or tumor volumes for observers 1, 2, and 3. Bland-Altman plots showed a small interobserver variability. The mean time to complete liver volumetry for one patient using OsiriX was 19 +/- 3 min.

CONCLUSIONS

OsiriX liver volumetry performed by surgeons is an accurate and time-efficient method for predicting resection volume and FLRV.

Value of indocyanine green clearance of the future liver remnant in predicting outcome after resection for biliary cancer

BACKGROUND

It is difficult to predict hepatic functional reserve accurately before major hepatectomy. The aim of this study was to analyse the usefulness of the future liver remnant plasma clearance rate of indocyanine green (ICGK-F, calculated as plasma clearance rate of indocyanine green (ICGK) x proportion of the future liver remnant) in predicting death after major hepatectomy.

METHODS

Data on ICGK and ICGK-F were collected prospectively and analysed retrospectively for 274 patients who underwent right hepatectomy, right trisectionectomy or left trisectionectomy for biliary cancer between 1991 and 2008. The mortality rate and incidence of postoperative complications were analysed. Patients were separated into two groups according to year of operation (85 patients operated on between 1991 and 2000; 189 from 2001 to 2008).

RESULTS

In multiple logistic regression analyses, an ICGK-F less than 0.05 had the strongest impact on the incidence of postoperative mortality (odds ratio 8.06; P < 0.001). The postoperative mortality rate was significantly lower in the later period (P < 0.001). In patients with an ICGK-F value between 0.040 and 0.049, the mortality rate in the early period was 30 per cent, whereas it was only 8 per cent in the later period.

CONCLUSION

An ICGK-F of 0.05 is a useful cut-off value for predicting mortality and morbidity. With careful perioperative patient management in an experienced institution, this cut-off value can be lowered further.

Indocyanine green R15 ratio depends directly on liver perfusion flow rate

BACKGROUND

Indocyanine green (ICG) is a synthetic dye that is widely used to evaluate liver function in critically ill patients, before liver resection or after liver transplantation. Controversy still exists about the impact exerted on the ICG ratio after 15 min (ICG R15) by differences in liver perfusion rates, hyperdynamic states, or patient cardiac output. We studied the role of different liver perfusion rates on the ICG R15 ratio in a normothermic extracorporeal liver perfusion system under standardized conditions.

METHODS

Livers from landrace pigs (40-50 kg) were perfused with fresh porcine blood. Normal and high perfusion rates were defined as 1 ml and 2 ml/g liver/min, respectively. Perfusate pressure of the hepatic artery and portal vein were within the physiological range in both groups. According to manufacturer's instructions, 0.5 mg of ICG per kg was applied and the ICG R15 was calculated. Calculations were based on fifteen experiments in five liver perfusions. Bile production, liver function and histology were analyzed.

RESULTS

All perfusions were characterized by physiological bile production, lack of hepatocellular damage and normal histology. ICG R15 ratio in group I, perfused with 1 ml/g liver, was 18.9 +/- 6%. In group II, perfused with 2 ml/g liver, the ICG R15 ratio was 7.2 +/- 3%. The difference between groups 1 and 2 was statistically significant (p < 0.05).

CONCLUSION

ICG R15 is reliable within one group at defined perfusion rates. Doubled perfusion rates contribute to higher ICG clearance. For clinical application we would like to suggest considering cardiac output of the patient for interpretation of ICG ratios.

Prediction of postoperative outcome after hepatectomy with a new bedside test for maximal liver function capacity

OBJECTIVE

To validate the LiMAx test, a new bedside test for the determination of maximal liver function capacity based on C-methacetin kinetics. To investigate the diagnostic performance of different liver function tests and scores including the LiMAx test for the prediction of postoperative outcome after hepatectomy.

SUMMARY BACKGROUND DATA

Liver failure is a major cause of mortality after hepatectomy. Preoperative prediction of residual liver function has been limited so far.

METHODS

Sixty-four patients undergoing hepatectomy were analyzed in a prospective observational study. Volumetric analysis of the liver was carried out using preoperative computed tomography and intraoperative measurements. Perioperative factors associated with morbidity and mortality were analyzed. Cutoff values of the LiMAx test were evaluated by receiver operating characteristic.

RESULTS

Residual LiMAx demonstrated an excellent linear correlation with residual liver volume (r = 0.94, P < 0.001) after hepatectomy. The multivariate analysis revealed LiMAx on postoperative day 1 as the only predictor of liver failure (P = 0.003) and mortality (P = 0.004). AUROC for the prediction of liver failure and liver failure related death by the LiMAx test was both 0.99. Preoperative volume/function analysis combining CT volumetry and LiMAx allowed an accurate calculation of the remnant liver function capacity prior to surgery (r = 0.85, P < 0.001).

CONCLUSIONS

Residual liver function is the major factor influencing the outcome of patients after hepatectomy and can be predicted preoperatively by a combination of LiMAx and CT volumetry.

Perioperative use of the LiMON method of indocyanine green elimination measurement for the prediction and early detection of post-hepatectomy liver failure

INTRODUCTION

A non-invasive liver function monitoring system, the LiMON, has been developed that measures indocyanine green (ICG) elimination by pulse spectrophotometry. The aim was to assess the relationship between pre and post-operative ICG plasma disappearance rate (ICG PDR %/min) values and the onset of post-hepatectomy liver dysfunction.

METHODS

37 patients scheduled for major liver resections were selected. None had chronic liver disease. IGC PDR was measured preoperatively and on days 1, five and 10 postoperatively. On the same day, serum liver function tests were measured.

RESULTS

The median preoperative and post-operative day 1 ICG PDR for the patients who developed liver dysfunction was significantly lower compared to those who did not (p=0.044, p=0.014). Significant correlation was found between ICG PDR measurement taken on postoperative day 1 and bilirubin level on day 1 (p=0.002), 5 (p=<0.001) and 10 (p=0.001). The same was true for ICG PDR on post-operative day 1 and albumin level on day 5 and 10 (p=0.003, p<0.001).

DISCUSSION

LiMON ICG PDR measured by pulse spectophotometry is a quick, non-invasive and reliable liver function test in patients undergoing liver resection that aids in the prediction and early detection of post-hepatectomy liver dysfunction.

Present status and future perspectives of preoperative portal vein embolization

BACKGROUND

Portal vein embolization (PVE) has been gaining increasing acceptance before major hepatectomy. This review presents the application, outcome, and recent developments of PVE.

METHODS

After a systematic search of "portal vein embolization" in PubMed, we reviewed and retrieved articles written in English related to PVE. There were no other criteria for exclusion of published information pertaining to this topic.

RESULTS

Hypertrophy of future liver remnants with PVE in patients with hepatobiliary malignancy results in fewer complications and shorter hospital stays after major hepatectomy, and add to the pool of candidates for surgical treatment. Some new techniques, such as sequential hepatic artery-portal vein embolization and PVE with stem cell administration, have showed a promising clinical future.

CONCLUSIONS

PVE has achieved significant improvement in the outcome of major hepatectomy, and has enlarged the candidate pool of liver resection as well. Future study is needed to identify the precise mechanism of liver regeneration after PVE.

Assessment of liver function for successful hepatectomy in patients with hepatocellular carcinoma with impaired hepatic function

BACKGROUND/PURPOSE

This study aimed to construct a formula for assessing liver function in order to prevent post-hepatectomy liver failure.

METHODS

A formula was constructed by analyzing data from 28 patients with hepatocellular carcinoma (HCC) with liver cirrhosis operated on between 1981 and 1984. Next, we evaluated the validity of this formula in 207 hepatectomy patients operated on from 1985 to 1999. For 145 hepatectomy patients operated on from 2000 to 2006, this formula was calculated before surgery in order to assess their risk of hepatectomy.

RESULTS

The formula for liver functional evaluation, constructed from preoperative hepatic function parameters, was: liver failure score = 164.8 - 0.58 x Alb - 1.07 x HPT + 0.062 x GOT - 685 x K. ICG - 3.57 x OGTT. LI + 0.074 x RW, where Alb is albumin (g/dl); HPT, hepaplastin test (%); GOT, glutamate oxaloacetate transaminase (U/l); K. ICG, K value of indocyanine green clearance test; OGTT. LI, 60-min/120-min glucose level in 75-g oral glucose tolerance test. linearity index of OGTT; and RW, weight of resected liver (g). We decided that a score below 25 would be safe for hepatectomy.

CONCLUSIONS

The mortality rate decreased from 3.9% in 1985--1999 to 1.3% in 2000--2006. This finding allows us to conclude that the formula is valid for assessing the risk of post-hepatectomy liver failure.

A new measure to assess the difficulty of liver resection

BACKGROUND

There is no valid measure to assess surgical difficulty and feasibility of a planned liver resection. It is the objective of this study to evaluate a mathematical measure from a 3D graphical analysis.

METHODS

Eleven different 3D models of hepatic tumours were evaluated by experts for resectability and analysed with Amira graphic software taking into consideration the portal and hepatic venous vascular relationships. Virtual resection volumes with increasing resection margins from 1 to 30 mm were determined separately for portal veins, hepatic veins, their intersections and volume unions. The integral of the increasing resection volumes was defined as risk coefficient. The risk coefficients from this volumetric analysis were compared with the expert opinion.

RESULTS

The risk coefficient based on the integral of portal venous and hepatic venous volume unions reproduced the expert opinion highly significantly (correlation coefficient 0.9, p<0.05) and more accurately than volumetric analysis of the planned resection margin.

CONCLUSION

With automated volumetric analysis, anatomically problematic situations in liver surgery can be reproduced and scaled. The risk coefficient obtained is a suitable objective measure for defining risk areas in liver surgery.

Liver volumetry plug and play: do it yourself with ImageJ

Background

A small remnant liver volume is an important risk factor for posthepatectomy liver failure and can be predicted accurately by computed tomography (CT) volumetry using radiologic image analysis software. Unfortunately, this software is expensive and usually requires support by a radiologist. ImageJ is a freely downloadable image analysis software package developed by the National Institute of Health (NIH) and brings liver volumetry to the surgeon’s desktop. We aimed to assess the accuracy of ImageJ for hepatic CT volumetry.

Methods

ImageJ was downloaded from http://www.rsb.info.nih.gov/ij/. Preoperative CT scans of 15 patients who underwent liver resection for colorectal cancer liver metastases were retrospectively analyzed. Scans were opened in ImageJ; and the liver, all metastases, and the intended parenchymal transection line were manually outlined on each slice. The area of each selected region, metastasis, resection specimen, and remnant liver was multiplied by the slice thickness to calculate volume. Volumes of virtual liver resection specimens measured with ImageJ were compared with specimen weights and calculated volumes obtained during pathology examination after resection.

Results

There was an excellent correlation between the volumes calculated with ImageJ and the actual measured weights of the resection specimens (r² = 0.98, p < 0.0001). The weight/volume ratio amounted to 0.88 ± 0.04 (standard error) and was in agreement with our earlier findings using CT-linked radiologic software.

Conclusion

ImageJ can be used for accurate hepatic CT volumetry on a personal computer. This application brings CT volumetry to the surgeon’s desktop at no expense and is particularly useful in cases of tertiary referred patients, who already have a proper CT scan on CD-ROM from the referring institution. Most likely the discrepancy between volume and weight results from exsanguination of the liver after resection.

[Liver resection for living-donor liver transplantation: anesthesia and intensive care aspects]

The living related donor mortality after liver donation could occur as a result of postoperative cardiovascular and thromboembolic complication; which could be minimized by detailed preoperative assessment of the living donor. The preoperative functional tests evaluate the physiological reserve or identify the living donors with limited response to the surgical stress. Based on the results of CT volumetry, MRI and liver functional reserve capacity test (indocyanine green retention ratio) the liver resection can be done safely. The preoperative cytochrome P enzymes tests of donors identify the drugs with abnormal metabolism. Balanced anesthesia combined with thoracic epidural anesthesia is done with liver safe, renal safe and ischemic preconditioning drugs. Normovolemic state is maintained with physiologic extrahepatic perfusion and oxygenation conditions. The central venous and hepatic artery pressure is reduced with the guarantee of optimal hepatic perfusion-oxygenation and better liver resection condition. Intraoperative thrombosis prophylaxis is performed with sequential compression device. After liver resection the donor morbidity can be reduced, effective analgesia, thrombosis prophylaxis, liver safe drug therapy and a tight monitoring. Before the first postoperative mobilization a deep vein Doppler ultrasound control is proposed.

Preoperative Portal Vein Embolization and Surgical Resection in Patients with Hepatocellular Carcinoma and Small Future Liver Remnant Volume: Comparison with Transarterial Chemoembolization

BACKGROUND

Preoperative portal vein embolization (PVE) increases the future liver remnant (FLR) volume, thus enabling surgical resection in patients with small FLR volume. It is unclear, however, if this approach can enhance survival in patients with hepatocellular carcinoma (HCC). We therefore compared the outcomes of preoperative PVE and surgical resection with transarterial chemoembolization (TACE).

METHODS

Changes in FLR volumes were analyzed in 32 HCC patients who underwent preoperative PVE and surgical resection. Long-term outcomes were compared with 64 TACE-treated patients matched for gender, Child-Turcotte-Pugh class, tumor size and number, serum alpha-fetoprotein levels, and UICC stage.

RESULTS

In the PVE group, the baseline ratio of FLR/total estimated liver volumes (TELV) was 27.6 +/- 7.2%. Following PVE, FLR volume increased 34% (336.5 vs 449.4 mL, P < .001) and the ratio of FLR/TELV increased from 27.6 +/- 7.2 to 36.9 +/- 8.1% (P < .001). There was no mortality associated with PVE or surgical resection. The 5-year survival rate was significantly higher in the PVE group than in the TACE group (71.9% vs 45.6%, P = .03). Multivariate analysis showed that treatment modality was an independent predictive factor for survival (odds ratio 2.05, 95% confidence interval 1.01-4.16, P = .046).

CONCLUSIONS

Preoperative PVE enables surgical resection in HCC patients with small FLR volume and improves patient survival compared with TACE.

Assessment of hepatic functional reserve by cirrhosis grading and liver volume measurement using CT

AIM: To explore a method for quantitative assessment of hepatic functional reserve by combining computed tomography (CT) volumetry with CT grading of liver cirrhosis before liver resection in patients with hepatocellular carcinoma.

METHODS: CT images of 55 patients undergoing liver resection were studied prospectively. The degree of liver cirrhosis was referred as "CT grade" and the percentage of remnant liver volume (PRLV) [PRLV = predicted RLV/predicted total liver volume (PTLV) × 100%; PTLV (mL) = 121.75 + 16.49 × body mass (kg)] were calculated by adding slice by slice of CT liver images. The postoperative RLV, pathologic stages of liver fibrosis in non-tumor area and survival time in these cases were analyzed.

RESULTS: There was a significant difference in survival time between the group with PRLV ≤ 50% and the group with PRLV > 50% (χ² = 4.988, P = 0.026), and between the group with CT grade 0/1 and the group with CT grade 2/3 (χ² = 5.429, P = 0.026). With combination of the both parameters, an oblique line was identified according to the distribution of 32 survivors versus 23 deceased subjects. The mortality rate above the line was 7.1% (1/14), and that below the line was 53.7% (22/41), indicating a significant difference between the two rates (χ² = 9.281, P = 0.002, P < 0.05).

CONCLUSION: PRLV and CT grades are significantly correlated with hepatic functional reserve. The predicted line using these two parameters is useful in candidates undergoing liver resection for judging hepatic functional reserve.

Management of hepatocellular carcinoma

Hepatocellular carcinoma is the fifth most common cancer in the world and is the third cause of cancer-related death with varying prevalence according to endemic risk factors. Despite therapeutic advances, there has not been significant improvement in the overall survival of patients who have hepatocellular cancer in the last 2 decades. Treatment selection should be based on tumor characteristics and the underlying liver disease.

Intraoperative margin re-resection for colorectal liver metastases

OBJECTIVE

Evaluate recurrence and survival in patients who underwent intraoperative margin re-resection for colorectal cancer liver (CRC) metastases.

DESIGN

Retrospective analysis.

SETTING

University Hospital, Cincinnati, Ohio. Academic medical center.

PARTICIPANTS

Cohort of 118 patients who underwent resection of CRC liver metastases between 1992 and 2004. All patients were divided into 3 groups: resection margin (MOR) less than 1 cm (n = 64), MOR greater than 1 cm (n = 33), and re-resection margin (re-MOR) greater than 1 cm (n = 21).

RESULTS

Patients with a margin greater than 1 cm, when compared with re-MOR greater than 1 had decreased incidence of liver and distant recurrence (p < 0.05) as well as improved disease-free survival (39.2 vs 22.9 months, p = 0.023). Differences in overall survival (58.6 vs 44.2 months, p = 0.14) were not significant.

CONCLUSION

Intraoperative re-resection is associated with an increased risk of local and distant recurrence, which may be a reflection of both inadequate surgery and underlying tumor biology.

Assessing liver function

PURPOSE OF REVIEW

This is a review on the techniques for assessing liver function in critically ill patients.

RECENT FINDINGS

Actually, there is no ideal real-time and bedside technique for assessing liver function in critically ill patients. Though not allowing to differentiate between liver blood flow and cell function, dynamic tests, that is indocyanine green plasma disappearance rate and lidocaine metabolism (monoethylglycinxylidide test), are superior, however, to static tests. Recently, the indocyanine green plasma disappearance rate, which nowadays can be measured reliably by a transcutaneous system in critically ill patients, was confirmed to correlate well with indocyanine green clearance. In general, the indocyanine green plasma disappearance rate is superior to bilirubin, which is still used as a marker of liver function, and comparable or even superior to complex intensive care scoring systems in terms of outcome prediction. Furthermore, indocyanine green plasma disappearance rate is more sensitive than serum enzyme tests for assessing liver dysfunction and early improvement in the indocyanine green plasma disappearance rate after onset of septic shock is associated with better outcome.

SUMMARY

Since no ideal tool is currently available, dynamic tests such as indocyanine green plasma disappearance rate and monoethylglycinxylidide test may be recommended for assessing liver function in critically ill patients. The indocyanine green plasma disappearance rate has the advantage, however, of being measurable noninvasively at the bedside and providing results within a few minutes.