Modification of acid-base balance in cirrhotic patients undergoing liver resection for hepatocellular carcinoma

No Good Deed: Acidosis in Chronic Kidney and Liver Disease

OBJECTIVE

Studies have shown that low or high serum bicarbonate levels (reflecting metabolic acidosis or alkalosis) are associated with increased all-cause mortality rates in moderate and advanced chronic kidney disease (CKD) cases. Correction of presumed acidosis using sodium bicarbonate, targeting serum levels around 22 mmol/L, has proven to be beneficial in delaying the progression of the disease and provided mortality benefit. A similar prognostic association may exist between uncorrected metabolic acidosis in chronic liver disease. Correcting it with sodium-containing salts may require more interventions due to increased sodium/fluid load. In patients with liver failure, a naturally alkalotic state, where sodium load is a concern, the impact of this intervention is unclear.

DESIGN

This study aims to generate proof of concept through a retrospective chart review in individuals with CKD-related metabolic acidosis and liver cirrhosis.

RESULT

Our analysis revealed a statistically significant association between the need for paracentesis and bicarbonate therapy. Our study has multiple drawbacks, including a retrospective chart review and limitation of data due to single-center patients.

CONCLUSION

We extrapolate that lowering bicarbonate targets in other clinical scenarios like liver failure, pregnancy, and cardiac failure may be prudent and will lead to a lower sodium load.

Clearance of the liver remnant predicts short-term outcome in patients undergoing resection of hepatocellular carcinoma

BACKGROUND

Estimation of the functional reserve of the remnant liver is important to reduce morbidity and mortality.

AIM

To estimate the functional reserve of the remnant liver in patients with hepatocellular carcinoma (HCC).

METHODS

We reviewed the medical records of 199 patients who underwent resection of HCC. Hepatic clearance of the remnant liver was calculated using fusion images of ^99mTc-labelled galactosyl-human serum albumin liver scintigraphy and computed tomography. Posthepatectomy liver failure (PHLF) was classified according to the International Study Group of Liver Surgery. Complications was classified according to Clavien–Dindo classification. We analyzed by the risk factors for PHLF, morbidity and mortality with multivariate analysis.

RESULTS

Twenty-seven (30%) patients had major complications and 23 (12%) developed PHLF. The incidence of major complications increased with increasing albumin–bilirubin (ALBI) grade. The area under the curve values for hepatic clearance of the remnant liver, liver to heart-plus-liver radioactivity at 15 min (LHL15), and ALBI score predicting PHLF were 0.868, 0.629, and 0.655, respectively. The area under the curve for hepatic clearance of the remnant liver, LHL15, and ALBI score predicting major complications were 0.758, 0.594, and 0.647, respectively. The risk factors for PHLF and major complications were hepatic clearance of the remnant liver and intraoperative bleeding.

CONCLUSION

The measurement of hepatic clearance may predict PHLF and major complications for patients undergoing resection of HCC.

Use of a novel index, the A-index, and its associated nomogram to predict overall survival rates after resection of primary hepatocellular carcinoma

BACKGROUND

Several international staging or scoring systems don't accurately predict overall survival (OS) after resection of primary hepatocellular carcinoma (PHCC). Therefore, we attempted to overcome this limitation by constructing the A-index and its associated nomogram.

METHODS

We selected 672 patients who underwent curative resection of PHCC between January 2007 and February 2015 at the first affiliated hospital of the Wenzhou medical university. These subjects were randomly divided into the training (n = 470) and the validation group (n = 202) according to the ratio of 7:3.

RESULTS

We prepared the nomogram using eight independent risk factors including the A-index (calculated by 100 × aspartate transaminase /albumin /albumin) in the training cohort. The concordance index (C-index) of the nomogram for both training and validation set was similar in indicating the OS rate. The nomogram showed the strongest predictive power for the 1-year, 3-year, and 5-year OS, with the area under the ROC curve being 0.8182, 0.7892, and 0.7669, respectively. Correction curves showed consistent performance for both groups, stratification of the Kaplan-Meier curve was significant (P < 0.001), and decision curve analysis (DCA) showed the superiority of nomograms considering clinical effects.

CONCLUSIONS

The predictive power of the nomogram integrating the A-index for OS was optimal.

Prediction of posthepatectomy liver failure using transient elastography in patients with hepatitis B related hepatocellular carcinoma

Background

It is essential to accurately predict Postoperative liver failure (PHLF) which is a life-threatening complication. Liver hardness measurement (LSM) is widely used in non-invasive assessment of liver fibrosis. The aims of this study were to explore the application of preoperative liver stiffness measurements (LSM) by transient elastography in predicting postoperative liver failure (PHLF) in patients with hepatitis B related hepatocellular carcinoma.

Methods

The study included 247 consecutive patients with hepatitis B related hepatocellular carcinoma who underwent hepatectomy between May 2015 and September 2015. Detailed preoperative examinations including LSM were performed before hepatectomy. The endpoint was the development of PHLF.

Results

All of the patients had chronic hepatitis B defined as the presence of hepatitis B surface antigen (HBsAg) for more than 6 months and 76 (30.8%) had cirrhosis. PHLF occurred in 37 (14.98%) patients. Preoperative LSM (odds ratio, OR, 1.21; 95% confidence interval, 95% CI: 1.13–1.29; P < 0.001) and international normalized ratio (INR) (OR, 1.07; 95% CI: 1.01–1.12; P < 0.05) were revealed to be independent risk factors for PHLF, and a new model was defined as LSM-INR index (LSM-INR index = 0.191*LSM + 6.317*INR-11.154). The optimal cutoff values of LSM and LSM-INR index for predicting PHLF were 14 kPa (AUC 0.86, 95% CI: 0.811–0.901, P < 0.001) and −1.92 (AUC 0.87, 95% CI: 0.822–0.909, P < 0.001), respectively.

Conclusions

LSM can be helpful for surgeons to make therapeutic decisions in patients with hepatitis B related hepatocellular carcinoma.

Does acid-base equilibrium correlate with remnant liver volume during stepwise liver resection?

Small for size and flow syndrome (SFSF) is one of the most challenging complications following extended hepatectomy (EH). After EH, hepatic artery flow decreases and portal vein flow increases per 100 g of remnant liver volume (RLV). This causes hypoxia followed by metabolic acidosis. A correlation between acidosis and posthepatectomy liver failure has been postulated but not studied systematically in a large animal model or clinical setting. In our study, we performed stepwise liver resections on nine pigs to defined SFSF limits as follows: step 1: segment II/III resection, step 2: segment IV resection, step 3: segment V/VIII resection (RLV: 75, 50, and 25%, respectively). Blood gas values were measured before and after each step using four catheters inserted into the carotid artery, internal jugular vein, hepatic artery, and portal vein. The pH, [Formula: see text], and base excess (BE) decreased, but [Formula: see text] values increased after 75% resection in the portal and jugular veins. EH correlated with reduced BE in the hepatic artery. Pco₂ values increased after 75% resection in the jugular vein. In contrast, arterial Po₂ increased after every resection, whereas the venous Po₂ decreased slightly. There were differences in venous [Formula: see text], BE in the hepatic artery, and Pco₂ in the jugular vein after 75% liver resection. Because 75% resection is the limit for SFSF, these noninvasive blood evaluations may be used to predict SFSF. Further studies with long-term follow-up are required to validate this correlation.NEW & NOTEWORTHY This is the first study to evaluate acid-base parameters in major central and hepatic vessels during stepwise liver resection. The pH, [Formula: see text], and base excess (BE) decreased, but [Formula: see text] values increased after 75% resection in the portal and jugular veins. Extended hepatectomy correlated with reduced BE in the hepatic artery. Because 75% resection is the limit for small for size and flow syndrome (SFSF), postresection blood gas evaluations may be used to predict SFSF.

Successful Treatment of Severe Immune Thrombocytopenia After Orthotopic Liver Transplant

Here, we report a case of severe immune thrombocytopenia that occurred after orthotopic liver transplant. On day 16 after transplant, the patient was readmitted to our hospital with a platelet count of 0 cells/mL, with the count remaining at a low level of 1000 to 10 000 cells/mL for 46 days. A diagnosis was made, after exclusion of other causes, of thrombocytopenia. Platelet blood transfusion and high-dose prednisone (1mg/kg/d) combined with intravenous immunoglobulin (0.5g/kg/d) were administered with no improvement. After additional treatments, which included altered use of immunosuppressive agents, changing adefovir to lamivudine and continuous steroid therapy, the patient was discharged with a platelet count of 55 000 cells/mL. Both liver and renal functions generally stayed well during hospitalization. The patient was discharged uneventfully and achieved remission during 10-month follow-up after discharge.

Laparoscopic versus Open Liver Resection: Differences in Intraoperative and Early Postoperative Outcome among Cirrhotic Patients with Hepatocellular Carcinoma-A Retrospective Observational Study

Introduction. Laparoscopic liver resection is considered risky in cirrhotic patients, even if minor surgical trauma of laparoscopy could be useful to prevent deterioration of a compromised liver function. This study aimed to identify the differences in terms of perioperative complications and early outcome in cirrhotic patients undergoing minor hepatic resection for hepatocellular carcinoma with open or laparoscopic technique. Methods. In this retrospective study, 156 cirrhotic patients undergoing liver resection for hepatocellular carcinoma were divided into two groups according to type of surgical approach: laparoscopy (LS group: 23 patients) or laparotomy (LT group: 133 patients). Perioperative data, mortality, and length of hospital stay were recorded. Results. Groups were matched for type of resection, median number of nodules, and median diameter of largest lesions. Groups were also homogeneous for preoperative liver and renal function tests. Intraoperative haemoglobin decrease and transfusions of red blood cells and fresh frozen plasma were significantly lower in LS group. MELD score lasted stable after laparoscopic resection, while it increased in laparotomic group. Postoperative liver and renal failure and mortality were all lower in LS group. Conclusions. Lower morbidity and mortality, maintenance of liver function, and shorter hospital stay suggest the safety and benefit of laparoscopic approach.

Assessment of hepatic detoxification activity: proposal of an improved variant of the (13)c-methacetin breath test

Breath tests based on the administration of a (13)C-labeled drug and subsequent monitoring of (13)CO2 in the breath (quantified as DOB - delta over baseline) liberated from the drug during hepatic CPY-dependent detoxification are important tools in liver function diagnostics. The capability of such breath tests to reliably indicate hepatic CYP performance is limited by the fact that (13)CO2 is not exclusively exhaled but also exchanged with other compartments of the body. In order to assess this bias caused by variations of individual systemic CO2 kinetics we administered intravenously the test drug (13)C-methacetin to 25 clinically liver-healthy individuals and monitored progress curves of DOB and the plasma concentration of (13)C-methacetin. Applying compartment modelling we estimated for each individual a set of kinetic parameters characterizing the time-dependent exchange of the drug and of CO2 with the liver and non-hepatic body compartments. This analysis revealed that individual variations in the kinetics of CO2 may account for up to 30% deviation of DOB curve parameters from their mean at otherwise identical (13)C-methacetin metabolization rates. In order to correct for this bias we introduced a novel detoxification score which ideally should be assessed from the DOB curve of a 2-step test ("2DOB") which is initialized with the injection of a standard dose of (13)C-labeled bicarbonate (in order to provide information on the actual CO2 status of the individual) followed by injection of the (13)C-labeled test drug (the common procedure). Computer simulations suggest that the predictive power of the proposed 2DOB breath test to reliably quantity the CYP-specific hepatic detoxification activity should be significantly higher compared to the conventional breath test.

Is portal hypertension a contraindication to hepatic resection?

BACKGROUND AND AIMS

The outcome of hepatic resection in cirrhotic patients has improved remarkably in recent years with improved surgical techniques and perioperative care; however, the role of portal hypertension is still uncertain. The aim of this study was to elucidate surgical outcomes of hepatectomy in patients with portal hypertension.

METHODS

Data from 241 cirrhotic patients who underwent resection for hepatocellular carcinoma were retrospectively collected and analyzed: patients were divided into 2 groups according to the presence (n = 89) or absence (n = 152) of portal hypertension at the time of surgery. To overcome biases owing to the different distribution of covariates throughout the 2 groups, a one-to-one match was created using propensity score analysis: after match, intraoperative, and postoperative course and survival rates were analyzed.

RESULTS

Patients with portal hypertension experienced worse preoperative liver function (mean model for end-stage liver disease [MELD] score, 9.5 +/- 7.8 vs. 8.4 +/- 1.3; P = 0.001) and survival rates (P = 0.008) in comparison to those without portal hypertension: after one-to-one matching, patients with (n = 78) and without portal hypertension (n = 78) had the same preoperative characteristics and showed the same intraoperative course, postoperative occurrence of liver failure, morbidity, length of in-hospital stay and survival rates (P = ns in all cases). The only predictors of postoperative liver failure were MELD score (P = 0.001) and extent of hepatectomy (P = 0.005).

CONCLUSIONS

Faced with the same MELD score and extent of hepatectomy planning, presence of portal hypertension should not be considered as a contraindication for hepatic resection in cirrhotic patients.

Comparison of recurrence of hepatocellular carcinoma after resection in patients with cirrhosis to its occurrence in a surveilled cirrhotic population

The presence of cirrhosis is the only risk factor that is advocated for recurrence of hepatocellular carcinoma (HCC) 2 years after hepatic resection compared with noncirrhotic control subjects; however, data for cohorts of exclusively patients with cirrhosis are lacking. This study was designed to assess risk factors and annual incidence of early (<2 years) and late (>2 years) recurrence after resection of cirrhosis and to compare these findings with those of patients with cirrhosis enrolled in HCC surveillance programs (HCC occurrence). Data from 204 patients with cirrhosis resected for HCC and 150 surveilled for cirrhosis were retrospectively collected and compared using propensity score matching to overcome biases of nonrandomized study. Risk factors for early recurrence (incidence = 21.8%/year) were higher serum alpha-fetoprotein (AFP) levels, poorly differentiated tumor, and presence of microvascular invasion (P < 0.05). Risk factors for both late recurrence (18.4%/year) and HCC occurrence (3.3%/year) were male gender, older age, and higher serum transaminase levels; multiple primary tumors and higher AFP were additional risk factors for late recurrence and HCC occurrence respectively (P < 0.05). After propensity adjustment, resected patients with less than two risk factors for late recurrence showed an annual incidence of HCC (6.2%/year) similar to that of surveilled patients with > or =2 risk factors (5.8%/year; P = 0.898). Early and late recurrence of HCC for patients with cirrhosis after resection have distinct risk factors. Annual incidence of HCC 2 years or more after resection may be similar to that of general patients because the same risk factors are involved; assessment of these characteristics could be useful in tailoring clinical management.

GDF15 triggers homeostatic proliferation of acid-secreting collecting duct cells

Although adult kidney cells are quiescent, enlargement of specific populations of epithelial cells occurs during repair and adaptive processes. A prerequisite to the development of regenerative therapeutics is to identify the mechanisms and factors that control the size of specific populations of renal cells. Unfortunately, in most cases, it is unknown whether the growth of cell populations results from transdifferentiation or proliferation and whether proliferating cells derive from epithelial cells or from circulating or resident progenitors. In this study, the mechanisms underlying the enlargement of the acid-secreting cell population in the mouse kidney collecting duct in response to metabolic acidosis was investigated. Acidosis led to two phases of proliferation that preferentially affected the acid-secreting cells of the outer medullary collecting duct. All proliferating cells displayed polarized expression of functional markers. The first phase of proliferation, which started within 24 h and peaked at day 3, was dependent on the overexpression of growth differentiation factor 15 (GDF15) and cyclin D1 and was abolished when phosphatidylinositol-3 kinase and mammalian target of rapamycin were inhibited. During this phase, cells mostly divided along the tubular axis, contributing to tubule lengthening. The second phase of proliferation was independent of GDF15 but was associated with induction of cyclin D3. During this phase, cells divided transversely. In summary, acid-secreting cells proliferate as the collecting duct adapts to metabolic acidosis, and GDF15 seems to be an important determinant of collecting duct lengthening.