Resected Liver Volume Research Articles

Effect of ethanolamine on liver regeneration after 90% hepatectomy in rats

SURGICAL PROCEDURES, such as extended liver resection or living-related liver transplantation may be performed because normal liver has vigorous regenerative potential. However, reduced hepatic volume can produce postoperative hepatic insufficiency, which is a serious problem. After extensive liver resection for hepatic tumor or in living-related liver donors maximum volume of liver resection or thus the minimum volume of donor liver are limited. When the volume exceeds these limits, surgical treatment is not indicated. However, a new treatment that promotes postoperative liver regeneration would extend these limits. Two approaches have been attempted to promote liver regeneration. One approach prepares the host environment for liver regeneration by plasma exchange. In recent years, favorable results also have been reported using a bioartificial liver as a bridge. The other approach is promotion of liver regeneration using hepatocyte growth factor (HGF) or ethanolamine (EA). EA is a nutrient factor derived from the small intestine. In this study, we investigated the enhancing effect of EA using a 90% partial hepatectomy (PHX) rat model.

Formula omitted]-[1-13C]Alanine Is a Useful Substance for the Evaluation of Liver Function

Background. Using a rat model of hepatectomy, we investigated whether the severity of hepatopathy could be quantitatively measured from changes in expiratory 13CO2 levels after intravenous administration of l-[1-13C]alanine.Materials and Methods. Under nembutal anesthesia, 20 mg/kg l-[1-13C]alanine was administered to rats via the femoral vein, and expiratory 13CO2 levels were measured for 15 min. Then, 30, 70, or 90% hepatectomy was performed. In the control group, simple laparotomy was performed. A breath test was conducted 20 min after laparotomy. We examined the correlation of total 13CO2 output (S) or single point 13CO2 level (SP) every 1 min for 15 min with liver weight/body weight (LW/BW) (%).Results. In the control group, the breath test graph showed a specific peak level about 3 min after administration, but in all groups undergoing hepatectomy, it did not show any peak level during measurement. The correlation coefficient between S12–15 after l-[1-13C]alanine administration and LW/BW was 0.902 (P < 0.0001). The correlation coefficient between SP7 after l-[1-13C]alanine administration and LW/BW was highest, 0.908 (P < 0.0001). The severity of hepatopathy could also be evaluated, with significant differences in S12–14 compared to control when the volume of resected liver was 30% or greater, but there was no significant difference between the groups undergoing 70 and 90% hepatectomy. However, the severity of hepatopathy could be evaluated, with significant differences in S15 and SP7 in all comparisons between groups.Conclusion. In the breath test with intravenously administered l-[1-13C]alanine, the severity of hepatopathy could be quantitatively evaluated in a short period by measuring S15 and SP7.

Hepatocyte Growth Factor Concentration in Rat Bile Is Affected by Hepatic Resection Volume and External Biliary Drainage

Background/aims. Hepatocyte growth factor (HGF) concentrations in bile have been shown to be useful in the early assessment of liver function after hepatectomy. The aim of the present study is to prove the hypothesis that the level of bile HGF is proportional to the regeneration capacity of the liver using a rat model.Methods. Blood and bile were sampled from rats who underwent 30 or 70% hepatectomy, with or without biliary drainage. HGF concentrations were determined using enzyme-linked immunosorbent assay.Results. Liver regeneration was significantly suppressed after hepatectomy in the rats that underwent external biliary drainage. The bile HGF concentration was positively correlated with the resected liver volume within 24 h of hepatectomy, and HGF levels were markedly increased by external biliary drainage. The postoperative changes in plasma HGF were less dramatic.Conclusions. HGF appears to play an important role in liver regeneration. Bile HGF concentrations, unlike plasma HGF levels, are a good reflection of the hepatic biosynthesis of this growth factor. Increased concentrations of HGF in bile after external biliary drainage may reflect a compensatory response to the continuous loss of hepatocyte growth factor-rich fluid.

Hepatectomy with microwave tissue coagulator: with special reference to combination of hemi-or total hepatic vascular occulusion

We investigated the advantage to hepatectomy with combination of microwave tissue coagulator (MTC) and hepatic vascular occulusion. Fourty one consecutive patients undergoing hepatic resection by our method were evaluated with references to comparison of reported hepatectomized cases using MTC without hepatic vascular clamp. We performed microwave coagulation only along the intended liver surface resection line and no more, then urtrasonically guided liver resection initiated along with coagulated line by forceps frature method with intermittent vasucular occulusion. The efficacy of MTC in hepatectomy, as many authors reported, was reduction in blood loss during operation without vasucular clamp i.e. warm ischemia of the liver which regarded as contraindicates to dameged liver. This 41 consecutive liver resections consisted of partial (Hr0 : 13), subsegmental (Hr1 : 13), segmental (Hr1 : 8), lobar (Hr2 : 1), extended lobar (Hr2 + : 1). In this study, the cases of postoprerative intrperitoneal infection, bile lekage, hemorrhage, was one respectively (2.4%) and ascites were 2 cases (4.9%), pleural effusion were 3 cases (7.3%). The average amount of blood loss was 763 ± 110 ml and average volume of resected liver was 194 ± 209g. The post operative laboratory data related to liver function changed within accepatable range reasonable for operative magnitude. Intraperative blood loss, postoperative complications' rates, postoperarive clinical courses were all not only diferent with using MTC without hepatic clamp but also more favorable results. No complications attributable to combined usage of MTC and vascular clamp were emerged.We concluded that combination of MTC and hepatic vascular occlusion was very useful for safer hepatic resection.

Advantage of preoperative portal vein occlusion for hepatectomy that exceeds portal vein occluded lobes

Background: The purpose of our study was to examine the effect of preoperative portal vein (PV) occlusion on hepatic reserve function after extended hepatectomy that is an excision of areas beyond the PV occluded lobes. Methods: Male Wistar rats were divided into three groups and underwent a two-stage operation: a PVL-hepatectomy group (ligation of the PV [PVL] of the left and median lobes followed by hepatectomy of the right lobes together with the PV occluded lobes), a sham-88% hepatectomy group (sham operation without PVL followed by hepatectomy corresponding to the lobes excised in the PVL-hepatectomy group), and a sham-67% hepatectomy group (sham operation followed by hepatectomy of the left and median lobes to approximate the volume excised in the PVL-hepatectomy group). In all subjects, hepatectomy was carried out 7 days after the PVL or sham operation. On days 0, 1, 2, and 3 after hepatectomy, liver weight, histologic elements, DNA synthesis rates, energy charge, adenine nucleotides, and lipoperoxide levels of the remaining liver were determined. Results: In the sham-88% hepatectomy group, the volume of resected liver was 88.2% ± 0.5%. In the PVL-hepatectomy group it was 69.1% ± 0.8%, although anatomically identical lobes were excised. At the time of hepatectomy, DNA synthesis, hepatic concentrations of adenine nucleotides and lipoperoxide, and serum liver function tests showed similar results in all three groups. The survival rate 3 days after hepatectomy was significantly low (53%) in the sham-88% hepatectomy group, whereas it was 100% in the PVL-hepatectomy and sham-67% hepatectomy groups. The gain in liver weight per day was significantly lower in the sham-88% hepatectomy group than in the other two groups. The decline in hepatic energy charge after hepatectomy was less, with less activated DNA synthesis, in the PVL-hepatectomy group compared with the sham-88% hepatectomy and sham-67% hepatectomy groups. Lipoperoxide concentration in the PVL-hepatectomy group was significantly lower than that in the sham-88% hepatectomy and sham-67% hepatectomy groups. Conclusions: Preoperative PV occlusion not only increases the remaining liver volume but also is advantageous to hepatic reserve after hepatectomy that exceeds PV occluded lobes. (Surgery 1998;123:545-53.)

Radiation tolerance of cirrhotic livers in relation to the preserved functional capacity: Analysis of patients with hepatocellular carcinoma treated by focused proton beam radiotherapy

Purpose : To determine the preserved functional capacity of the liver as a probable determinant of radiation tolerance in patients with cirrhosis and hepatocellular carcinoma, who underwent proton beam radiotherapy. Materials and Methods : We reviewed computed tomographic (CT) scans of 26 patients with cirrhosis and hepatocellular carcinoma during a period of 12–27 months after proton beam radiotherapy. Tumors were treated with focused proton beams with target doses of 140–186 TDF (time, dose, and fractionation). We measured the degree of hypertrophy of the untreated liver volume by measuring the total liver volume and the treated liver volume which was radiologically identified on contrast-enhanced CT scans. The risk of radiation-induced liver failure was estimated using the prediction score (PS) originally used for estimating posthepatectomy liver failure, substituting the planned treated liver volume for the resection liver volume. Results : The degree of hypertrophy ranged from —19% to 51%, and was significantly positively correlated with the ratio of the planned treated liver volume to the functional liver volume. The PS agreed well with observed radiation tolerance in 21 patients, but underestimated the tolerance in 5. This underestimation was diminished when the PS was recalculated using the identified untreated liver volume in lieu of the planned untreated liver volume. Conclusion : As in surgical treatment, radiation tolerance of the cirrhotic liver after focused treatement is closely related to the preserved functional capacity of the identified untreated liver volume, which shows compensatory hypertrophy following radiotherapy.

Regulating factors of liver regeneration after hepatectomy

The factors regulating liver regeneration were studied by measuring changes in the liver volume and serum hepatocyte growth factor (HGF) levels after hepatectomy. Changes in the liver volumes were studied in 68 hepatectomized patients, including (A) hepatoma patients who had chronic hepatitis or liver cirrhosis (n = 44) and (B) metastatic liver cancer patients who had normal liver parenchyma (n = 24). The hepatic volume increased by 13.8% of the remnant hepatic volume in group A and by 49.1% in group B. The examined factors included the percentage of resected liver volume (%RLV) and the results of laboratory tests. Regression analysis showed that in group A, both %RLV (beta = 0.46) and the serum total bilirubin (T-Bil) level (beta = -0.33) correlated significantly with the extent of liver regeneration and that in group B, only %RLV (beta = 0.78) correlated significantly with the regeneration. Serum HGF levels after hepatectomy were studied in 21 hepatectomized patients, including 11 hepatoma patients and 10 patients with some types of metastatic liver cancer. Serum HGF levels increased significantly after surgery in all 21 patients. Regression analysis, however, showed that the change in HGF was related to liver cirrhosis (beta = 0.46) and to the maximal postoperative T-Bil level (beta = 0.51) but not to the extent of liver regeneration after hepatectomy. These results suggest that liver regeneration is regulated primarily by factors relating to the percentage of the resected liver parenchyma and that serum HGF levels do not directly relate to liver regeneration after surgery.

Serum hepatocyte growth factor levels in hepatectomized and nonhepatectomized surgical patients

Serum hepatocyte growth factor levels were measured in hepatectomized and nonhepatectomized surgical patients. The levels were significantly increased and reached a maximum within 7 days after surgery in both groups, returning to preoperative levels 28 days after partial hepatectomy and 7 days after other operations. Multiple regression analysis showed that such maximal hepatocyte growth factor levels were significantly related to having liver cirrhosis and postoperative maximal serum total bilirubin and alanine aminotransferase levels and peripheral white blood cell counts in the hepatectomized group and to postoperative maximal peripheral white blood cell counts and serum C-reactive protein levels in the nonhepatectomized group. However, the levels showed no relation to the resected liver volume and increment of the remaining liver volume 28 days after partial hepatectomy. It is concluded that serum hepatocyte growth factor levels were increased after partial hepatectomy in association with hepatocellular dysfunction and necrosis and systemic inflammation. It is unlikely that the increase was related to liver regeneration.

Pesticides and Food Additives

<h3>Background:</h3> Liver resection (LR) is the only curative therapy for hepatic malignancy. Despite this, the rates of LR across Canada are unknown. We sought to determine the rate and regional variation of LR in Canada, its provinces and census divisions for the period 1995–2004. <h3>Methods:</h3> We obtained discharge data for 1995–2004 from all provinces but Quebec from the Canadian Institute for Health Information, and we searched for LR by residential site. Then we calculated rates and variations in rates. <h3>Results:</h3> The national age- and sex-adjusted rate of LR per 100 000 people aged 18 years and older increased from 3.22 in 1995 to 5.86 in 2004. There was a high degree of variation across provinces and census divisions. <h3>Conclusion:</h3> Liver resection volumes are increasing in Canada. Significant regional variation exists for LR in Canada, likely reflecting a variety of important supply–demand issues.