Effects of the intermittent Pringle manoeuvre on hepatic gene expression and ultrastructure in a randomized clinical study

Effect of intermittent Pringle maneuver on perioperative outcomes and long-term survival following liver resection in patients with hepatocellular carcinoma: a meta-analysis and systemic review

BACKGROUND

Intermittent Pringle maneuver (IPM) is commonly used to control bleeding during liver resection. IPM can cause ischemia-reperfusion injury, which may affect the prognosis of patients with hepatocellular carcinoma (HCC). The present meta-analysis was conducted to evaluate the effect of IPM use on perioperative outcomes and long-term survival in patients with HCC.

METHODS

A systemic literature search was performed in the PubMed, Embase, Web of Science, and Cochrane Library databases to identify randomized controlled trials and retrospective studies that compared the effect of IPM with no Pringle maneuver during liver resection in patients with HCC. Hazard ratio (HR), risk ratio, standardized mean difference, and their 95% confidence interval (CI) values were calculated based on the type of variables.

RESULTS

This meta-analysis included nine studies comprising one RCT and eight retrospective studies and involved a total of 3268 patients. Perioperative outcomes, including operation time, complications, and length of hospital stay, except for blood loss, were comparable between the two groups. After removing the studies that led to heterogeneity, the results showed that IPM was effective in reducing blood loss. Five studies reported overall survival (OS) and disease-free survival (DFS) data and eight studies reported perioperative outcomes. No significant difference in OS and DFS was observed between the two groups (OS: HR, 1.01; 95% CI, 0.85-1.20; p = 0.95; DFS: HR, 1.01; 95% CI, 0.88-1.17; p = 0.86).

CONCLUSION

IPM is a useful technique to control blood loss during liver resection and does not affect the long-term survival of patients with HCC.

Machine perfusion of the liver and bioengineering

With the increasing number of accepted candidates on waiting lists worldwide, there is an urgent need to expand the number and the quality of donor livers. Dynamic preservation approaches have demonstrated various benefits, including improving liver function and graft survival, and reducing liver injury and post-transplant complications. Consequently, organ perfusion techniques are being used in clinical practice in many countries. Despite this success, a proportion of livers do not meet current viability tests required for transplantation, even with the use of modern perfusion techniques. Therefore, devices are needed to further optimise machine liver perfusion - one promising option is to prolong machine liver perfusion for several days, with ex situ treatment of perfused livers. For example, stem cells, senolytics, or molecules targeting mitochondria or downstream signalling can be administered during long-term liver perfusion to modulate repair mechanisms and regeneration. Besides, today's perfusion equipment is also designed to enable the use of various liver bioengineering techniques, to develop scaffolds or for their re-cellularisation. Cells or entire livers can also undergo gene modulation to modify animal livers for xenotransplantation, to directly treat injured organs or to repopulate such scaffolds with "repaired" autologous cells. This review first discusses current strategies to improve the quality of donor livers, and secondly reports on bioengineering techniques to design optimised organs during machine perfusion. Current practice, as well as the benefits and challenges associated with these different perfusion strategies are discussed.

Hemihepatic versus total hepatic inflow occlusion for laparoscopic hepatectomy: A randomized controlled trial

BACKGROUND

An appropriate bleeding control technique for laparoscopic liver resection (LLR) is needed to decrease intraoperative blood loss and avoid large hemorrhages. To date, hemihepatic inflow occlusion (HIO) versus total hepatic inflow occlusion (TIO) for LLR is still controversial. Thus, we performed this randomized controlled trial (ChiCTR-IOR-17013866) to compare the perioperative outcomes between HIO and TIO for LLR.

METHODS

From December 2017 to August 2019, patients met the criteria via surgical exploration in the operation room and were randomly assigned to both groups. Perioperative data between both groups were recorded and compared, and subgroup analysis was further performed.

RESULTS

258 patients were allocated to the TIO (n = 129) and HIO (n = 129) groups, respectively. There was no significant difference between the two groups in terms of intraoperative blood loss, operative time, postoperative complications, changes in postoperative liver function or early mortality. However, for patients whose transection plane was located on the liver Cantlie's plane, subgroup analysis results indicated that TIO had a shorter operative time (median, 220 vs. 240 min, P = 0.030) and occlusion time (median, 45 vs. 60 min, P = 0.011) and less intraoperative blood loss (median, 200 vs. 300 ml, P = 0.002) than HIO, whereas the morbidity and mortality of the two groups were comparable.

CONCLUSION

Both the TIO and HIO approaches could be safely performed for LLR in selected patients when performed by experienced surgeons. The TIO technique for LLR had the advantage of being easier to master than the HIO approach. Additionally, when the transection plane was located on the liver Cantlie's plane, TIO seems to have some superior perioperative outcomes.

Shorter Survival after Liver Pedicle Clamping in Patients Undergoing Liver Resection for Hepatocellular Carcinoma Revealed by a Systematic Review and Meta-Analysis

Simple Summary

Hepatocellular carcinoma (HCC) is the most prevalent tumor of the liver and represents the second most common cause of oncological-related deaths worldwide. Despite all progress made in the field, surgical resection or liver transplantation are, at the moment, the only curative therapies available. Liver resection, especially for large, central tumors, are at risk of important bleeding. Significative hemorrhage during HCC resections have been linked to an increased rate of post-operative complications and tumor recurrence. Therefore, hepatic pedicle clamping during surgery has been used in order to reduce the bleeding risks. However, this method induces ischemia/reperfusion injuries, which has also been associated with tumor recurrence. For this reason, we aimed to evaluate if pedicle clamping is indeed associated with tumor recurrence and shorter survival, by performing a systematic review of the literature and meta-analysis.

Abstract

Liver pedicle clamping minimizes surgical bleeding during hepatectomy. However, by inducing ischemia-reperfusion injury to the remnant liver, pedicle clamping may be associated with tumor recurrence in the regenerating liver. Hepatocellular carcinoma (HCC) having a high rate of recurrence, evidences demonstrating an eventual association with pedicle clamping is strongly needed. We did a systematic review of the literature until April 2020, looking at studies reporting the impact of liver pedicle clamping on long-term outcomes in patients undergoing liver resection for HCC. Primary and secondary outcomes were overall survival (OS) and disease-free survival, respectively. Results were obtained by random-effect meta-analysis and expressed as standardized mean difference (SMD). Eleven studies were included, accounting for 8087 patients. Results of seven studies were pooled in a meta-analysis. Findings indicated that, as compared to control patients who did not receive liver pedicle clamping, those who did had a significantly shorter OS (SMD = −0.172, 95%CI: −0.298 to −0.047, p = 0.007, I² = 76.8%) and higher tumor recurrence rates (odds ratio 1.36 1.01 to 1.83. p = 0.044, I² = 50.7%). This meta-analysis suggests that liver pedicle clamping may have a deleterious impact on long-term outcomes. An individual patient-data meta-analysis of randomized trials evaluating liver pedicle clamping is urgently needed.

Prognostic Impact of Pedicle Clamping during Liver Resection for Colorectal Metastases

Pedicle clamping (PC) during liver resection for colorectal metastases (CRLM) is used to reduce blood loss and allogeneic blood transfusion (ABT). The effect on long-term oncologic outcomes is still under debate. A retrospective analysis of the impact of PC on ABT-demand regarding overall (OS) and recurrence-free survival (RFS) in 336 patients undergoing curative resection for CRLM was carried out. Survival analysis was performed by both univariate and multivariate methods and propensity-score (PS) matching. PC was employed in 75 patients (22%). No increased postoperative morbidity was monitored. While the overall ABT-rate was comparable (35% vs. 37%, p = 0.786), a reduced demand for more than two ABT-units was observed (p = 0.046). PC-patients had better median OS (78 vs. 47 months, p = 0.005) and RFS (36 vs. 23 months, p = 0.006). Multivariate analysis revealed PC as an independent prognostic factor for OS (HR = 0.60; p = 0.009) and RFS (HR = 0.67; p = 0.017). For PC-patients, 1:2 PS-matching (N = 174) showed no differences in the overall ABT-rate compared to no-PC-patients (35% vs. 40%, p = 0.619), but a trend towards reduced transfusion requirement (>2 ABT-units: 9% vs. 21%, p = 0.052; >4 ABT-units: 2% vs. 11%, p = 0.037) and better survival (OS: 78 vs. 44 months, p = 0.088; RFS: 36 vs. 24 months; p = 0.029). Favorable long-term outcomes and lower rates of increased transfusion demand were observed in patients with PC undergoing resection for CRLM. Further prospective evaluation of potential oncologic benefits of PC in these patients may be meaningful.

Pure laparoscopic versus open major hepatectomy for hepatocellular carcinoma with liver F4 cirrhosis without routine Pringle maneuver - A propensity analysis in a single center

BACKGROUND

/Aim: Laparoscopic hepatectomy has been gaining popularity but its evidence in major hepatectomy for cirrhotic liver is lacking. We studied the long-term outcomes of the pure laparoscopic approach versus the open approach in major hepatectomy without Pringle maneuver in patients with hepatocellular carcinoma (HCC) and cirrhosis using the propensity score analysis.

METHODS

We reviewed patients diagnosed with HCC and cirrhosis who underwent major hepatectomy as primary treatment. The outcomes of patients who received the laparoscopic approach were compared with those of propensity-case-matched patients (ratio, 4:1) who received the open approach. The matching was made on the following factors: tumor size, tumor number, age, sex, hepatitis serology, HCC staging, comorbidity, and liver function.

RESULTS

Twenty-four patients underwent pure laparoscopic major hepatectomy for HCC with cirrhosis. Ninety-six patients who underwent open major hepatectomy were matched by propensity scores. The laparoscopic group had less median blood loss (300 ml vs 645 ml, p = 0.001), shorter median hospital stay (6 days vs 10 days, p = 0.002), and lower rates of overall complication (12.5% vs 39.6%, p = 0.012), pulmonary complication (4.2% vs 25%, p = 0.049) and pleural effusion (p = 0.026). The 1-year, 3-year and 5-year overall survival rates in the laparoscopic group vs the open group were 95.2%, 89.6% and 89.6% vs 87.5%, 72.0% and 62.8% (p = 0.211). Correspondingly, the disease-free survival rates were 77.1%, 71.2% and 71.2% vs 75.8%, 52.7% and 45.5% (p = 0.422).

CONCLUSIONS

The two groups had similar long-term survival. The laparoscopic group had favorable short-term outcomes. Laparoscopic major hepatectomy without routine Pringle maneuver for HCC with cirrhosis is a safe treatment option at specialized centers.

Impact of Intermittent Pringle Maneuver on Long-Term Survival After Hepatectomy for Hepatocellular Carcinoma: Result from Two Combined Randomized Controlled Trials

BACKGROUND

Hepatectomy remains an important curative treatment for hepatocellular carcinoma (HCC). Intermittent Pringle maneuver (IPM) is commonly applied during hepatectomy for control of bleeding. Whether the ischemia/reperfusion injury brought by IPM adversely affects the operative outcomes is controversial. This study aims to examine whether the application of IPM during hepatectomy affects the long-term outcomes.

METHODS

Two randomized controlled trials (RCT) have been carried out previously to evaluate the short-term outcomes of IPM. The present study represented a post hoc analysis on the HCC patients from the first RCT and all patients from the second RCT, and the long-term outcomes were evaluated.

RESULTS

There were 88 patients each in the IPM group and the no-Pringle-maneuver (NPM) group. The patient demographics, type and extent of liver resection and histopathological findings were comparable between the two groups. The 1-, 3-, 5-year overall survival in the IPM and NPM groups was 92.0%, 82.0%, 72.1% and 93.2%, 68.8%, 58.1%, respectively (P = 0.030). The 1-, 3-, 5-year disease-free survival in the IPM and NPM groups was 73.6%, 56.2%, 49.7% and 71.6%, 49.4%, 40.3%, respectively (P = 0.366). On multivariable analysis, IPM was a favorable factor for overall survival (P = 0.035). Subgroup analysis showed that a clamp time of 16-30 min (P = 0.024) and cirrhotic patients with IPM (P = 0.009) had better overall survival.

CONCLUSION

IPM provided a better overall survival after hepatectomy for patients with HCC. Such survival benefit was noted in cirrhotic patients, and the beneficial duration of clamp was 16-30 min.

TRIAL REGISTRATION

NCT00730743 and NCT01759901 ( http://www.clinicaltrials.gov ).

Interpatient heterogeneity in hepatic microvascular blood flow during vascular inflow occlusion (Pringle manoeuvre)

BACKGROUND

Vascular inflow occlusion (VIO) during liver resections (Pringle manoeuvre) can be applied to reduce blood loss, however may at the same time, give rise to ischemia-reperfusion injury (IRI). The aim of this study was to assess the characteristics of hepatic microvascular perfusion during VIO in patients undergoing major liver resection.

METHODS

Assessment of hepatic microcirculation was performed using a handheld vital microscope (HVM) at the beginning of surgery, end of VIO (20 minutes) and during reperfusion after the termination of VIO. The microcirculatory parameters assessed were: functional capillary density (FCD), microvascular flow index (MFI) and sinusoidal diameter (SinD).

RESULTS

A total of 15 patients underwent VIO; 8 patients showed hepatic microvascular perfusion despite VIO (partial responders) and 7 patients showed complete cessation of hepatic microvascular perfusion (full responders). Functional microvascular parameters and blood flow levels were significantly higher in the partial responders when compared to the full responders during VIO (FCD: 0.84±0.88 vs. 0.00±0.00 mm/mm2, P<0.03, respectively, and MFI: 0.69-0.22 vs. 0.00±0.00, P<0.01, respectively).

CONCLUSIONS

An interpatient heterogeneous response in hepatic microvascular blood flow was observed upon VIO. This may explain why clinical strategies to protect the liver against IRI lacked consistency.

Progress in hepatectomy for hepatocellular carcinoma and peri-operation management

The global incidence of liver cancer continues to grow. Liver cancer, especially hepatocellular carcinoma, has high recurrence and mortality rates. Here, we review the past decade's diagnostic, therapeutic, and management strategies for hepatocellular carcinoma, and summarize new patient management approaches, including enhanced recovery after surgery, targeted therapy, and immunotherapy. We compare traditional and innovative management methods, which comprise developments in precision medicine, and consider their limitations. Ongoing innovation and technological advances enable surgeons to gain deeper understandings of the multidimensionality of hepatocellular carcinoma, thereby promoting the continuous development of precision therapy.

Short-term Preoperative Diet Decreases Bleeding After Partial Hepatectomy: Results From a Multi-institutional Randomized Controlled Trial

BACKGROUND

Our previous case series suggested that a 1-week, low-calorie and low-fat diet was associated with decreased intraoperative blood loss in patients undergoing liver surgery.

OBJECTIVE

The current study evaluates the effect of this diet in a randomized controlled trial.

METHODS

We randomly assigned 60 patients with a body mass index ≥25 kg/m(2) to no special diet or an 800-kcal, 20 g fat, and 70 g protein diet for 1 week before liver resection. Surgeons were blinded to diet assignment. Hepatic glycogen stores were evaluated using periodic acid Schiff (PAS) stains.

RESULTS

Ninety four percent of the patients complied with the diet. The diet group consumed fewer daily total calories (807 vs 1968 kcal, P < 0.001) and fat (21 vs 86 g, P < 0.001) than the no diet group. Intraoperative blood loss was less in the diet group: mean blood loss 452 vs 863 mL (P = 0.021). There was a trend towards decreased transfusion in the diet group (138 vs 322 mL, P = 0.06). The surgeon judged the liver to be easier to manipulate in the diet group: 1.86 versus 2.90, P = 0.004. Complication rate (20% vs 17%), length of stay (median 5 vs 4 days) and mortality did not differ between groups. There was no difference in hepatic steatosis between groups. There was less glycogen in hepatocytes in the diet group (PAS stain score 1.61 vs 2.46, P < 0.0001).

CONCLUSIONS

A short-course, low-fat, and low-calorie diet significantly decreases bleeding and makes the liver easier to manipulate in hepatic surgery.

Does Intermittent Pringle Maneuver Increase Postoperative Complications After Hepatectomy for Hepatocellular Carcinoma? A Randomized Controlled Trial

BACKGROUND

In a previous study, we have shown that intermittent Pringle maneuver (IPM) might increase postoperative complications after hepatectomy for various indications. Complications which thought to be related to IPM were ascites, pleural effusion, wound infection and intra-abdominal collection. The aim of this study was to test the hypothesis that applying IPM during hepatectomy for hepatocellular carcinoma (HCC) could increase postoperative complications.

METHODS

Between January 2013 and October 2016, eligible patients who received elective open hepatectomy for HCC were randomized to have IPM or no Pringle maneuver (NPM). Occurrence of various types of postoperative complications was specifically looked for. A routine postoperative day 5 abdominal ultrasound examination and chest X-ray were done to detect and grade any radiological ascites, pleural effusion and intra-abdominal collection.

RESULTS

Fifty IPM and 50 NPM patients with histological proven HCC were recruited for final analysis. Demographics and operative parameters were comparable between the two groups. The postoperative complication rates were similar (IPM 36.0 vs. NPM 28.0%, P = 0.391). However, in the IPM group, more patients developed radiological posthepatectomy ascites (42.0 vs. 22.0%, P = 0.032) and pleural effusion (66.0 vs. 38.0%, P = 0.005). In patients with histologically proven cirrhosis, there were 28 IPM and 25 NPM patients. Again, there was no difference in postoperative complication rate but more radiological posthepatectomy ascites and pleural effusion in the IPM group.

CONCLUSION

This trial was not able to detect a difference in postoperative complications whether IPM was applied or not, but use of IPM was associated with more subclinical ascites and pleural effusion. (ClinicalTrials.gov NCT01759901).

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT01759901.

Morphological alterations and redox changes associated with hepatic warm ischemia-reperfusion injury

AIM

To study the effects of warm ischemia-reperfusion (I/R) injury on hepatic morphology at the ultrastructural level and to analyze the expression of the thioredoxin (TRX) and glutaredoxin (GRX) systems.

METHODS

Eleven patients undergoing liver resection were subjected to portal triad clamping (PTC). Liver biopsies were collected at three time points; first prior to PTC (baseline), 20 min after PTC (post-ischemia) and 20 min after reperfusion (post-reperfusion). Electron microscopy and morphometry were used to study and quantify ultrastructural changes, respectively. Additionally, gene expression analysis of TRX and GRX isoforms was performed by quantitative PCR. For further validation of redox protein status, immunogold staining was performed for the isoforms GRX1 and TRX1.

RESULTS

Post-ischemia, a significant loss of the liver sinusoidal endothelial cell (LSEC) lining was observed (P = 0.0003) accompanied by a decrease of hepatocyte microvilli in the space of Disse. Hepatocellular morphology was well preserved apart from the appearance of crystalline mitochondrial inclusions in 7 out of 11 patients. Post-reperfusion biopsies had similar features as post-ischemia with the exception of signs of a reactivation of the LSECs. No changes in the expression of redox-regulatory genes could be observed at mRNA level of the isoforms of the TRX family but immunoelectron microscopy indicated a redistribution of TRX1 within the cell.

CONCLUSION

At the ultrastructural level, the major impact of hepatic warm I/R injury after PTC was borne by the LSECs with detachment and reactivation at ischemia and reperfusion, respectively. Hepatocytes morphology were well preserved. Crystalline inclusions in mitochondria were observed in the hepatocyte after ischemia.

Efficacy of high-intensity focused ultrasound-assisted hepatic resection (HIFU-AR) on blood loss reduction in patients with liver metastases requiring hepatectomy: study protocol for a randomized controlled trial

BACKGROUND

Liver resection is the only potentially curative treatment for colorectal liver metastases (LM). It is considered a safe procedure, but is often associated with blood loss during liver transection. Blood transfusions are frequently needed, but they are associated with increased morbidity and risk of recurrence. Many surgical devices have been developed to decrease blood loss. However, none of them has proven superior to the standard crushing technique. We developed a new, powerful intra-operative high-intensity focused ultrasound (HIFU) transducer which destroys tissue by coagulative necrosis. We aim to evaluate whether HIFU-assisted liver resection (HIFU-AR) results in reduced blood loss.

METHODS

This is a prospective, single-centre, randomized (1:1 ratio), comparative, open-label phase II study. Patients with LM requiring a hepatectomy for ≥ 2 segments will be included. Patients with cirrhosis or sinusoidal obstruction syndrome with portal hypertension will be excluded. The primary endpoint is normalized blood loss in millilitres per square centimetre of liver section plane. Secondary endpoints are: total blood loss, transection time, transection time per square centimetre of liver area, haemostasis time, clip density on the liver section area, rate and duration of the Pringle manœuvre, rate of patients needing a blood transfusion, length of hospital stay, morbidity, patients with positive resection margin, and local recurrence. Assuming a blood loss of 7.6 ± 3.7 mL/cm² among controls, the study will have 85% power to detect a twofold decrease of blood loss in the experimental arm, using a Wilcoxon (Mann-Whitney) rank-sum test with a 0.05 two-sided significance level. Twenty-one randomized patients per arm are required. Considering the risk of contraindications at surgery, up to eight patients may be enrolled in addition to the 42 planned, with an enrolment period of 24 months. Randomization will be stratified by surgeon.

DISCUSSION

We previously demonstrated the safety and efficacy of intra-operative HIFU in patients operated on for LM. We also demonstrated the efficacy of HIFU-AR in a preclinical study. Participants in the HIFU-AR group of this randomized trial can expect to benefit from reduced blood loss and decreased ischemia of liver parenchyma.

TRIAL REGISTRATION

Clinicaltrial.gov, NCT02728167 . Registered on 22 March 2016.

Methods to decrease blood loss during liver resection: a network meta-analysis

BACKGROUND

Liver resection is a major surgery with significant mortality and morbidity. Specialists have tested various methods in attempts to limit blood loss, transfusion requirements, and morbidity during elective liver resection. These methods include different approaches (anterior versus conventional approach), use of autologous blood donation, cardiopulmonary interventions such as hypoventilation, low central venous pressure, different methods of parenchymal transection, different methods of management of the raw surface of the liver, different methods of vascular occlusion, and different pharmacological interventions. A surgeon typically uses only one of the methods from each of these seven categories. The optimal method to decrease blood loss and transfusion requirements in people undergoing liver resection is unknown.

OBJECTIVES

To assess the effects of different interventions for decreasing blood loss and blood transfusion requirements during elective liver resection.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and Science Citation Index Expanded to September 2015 to identify randomised clinical trials. We also searched trial registers and handsearched the references lists of identified trials.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or publication status) comparing different methods of decreasing blood loss and blood transfusion requirements in people undergoing liver resection.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified trials and collected data. We assessed the risk of bias using Cochrane domains. We conducted a Bayesian network meta-analysis using the Markov chain Monte Carlo method in WinBUGS 1.4, following the guidelines of the National Institute for Health and Care Excellence Decision Support Unit guidance documents. We calculated the odds ratios (OR) with 95% credible intervals (CrI) for the binary outcomes, mean differences (MD) with 95% CrI for continuous outcomes, and rate ratios with 95% CrI for count outcomes, using a fixed-effect model or random-effects model according to model-fit. We assessed the evidence with GRADE.

MAIN RESULTS

We identified 67 randomised clinical trials involving a total of 6197 participants. All the trials were at high risk of bias. A total of 5771 participants from 64 trials provided data for one or more outcomes included in this review. There was no evidence of differences in most of the comparisons, and where there was, these differences were in single trials, mostly of small sample size. We summarise only the evidence that was available in more than one trial below. Of the primary outcomes, the only one with evidence of a difference from more than one trial under the pair-wise comparison was in the number of adverse events (complications), which was higher with radiofrequency dissecting sealer than with the clamp-crush method (rate ratio 1.85, 95% CrI 1.07 to 3.26; 250 participants; 3 studies; very low-quality evidence). Among the secondary outcomes, the only differences we found from more than one trial under the pair-wise comparison were the following: blood transfusion (proportion) was higher in the low central venous pressure group than in the acute normovolemic haemodilution plus low central venous pressure group (OR 3.19, 95% CrI 1.56 to 6.95; 208 participants; 2 studies; low-quality evidence); blood transfusion quantity (red blood cells) was lower in the fibrin sealant group than in the control (MD -0.53 units, 95% CrI -1.00 to -0.07; 122 participants; 2; very low-quality evidence); blood transfusion quantity (fresh frozen plasma) was higher in the oxidised cellulose group than in the fibrin sealant group (MD 0.53 units, 95% CrI 0.36 to 0.71; 80 participants; 2 studies; very low-quality evidence); blood loss (MD -0.34 L, 95% CrI -0.46 to -0.22; 237 participants; 4 studies; very low-quality evidence), total hospital stay (MD -2.42 days, 95% CrI -3.91 to -0.94; 197 participants; 3 studies; very low-quality evidence), and operating time (MD -15.32 minutes, 95% CrI -29.03 to -1.69; 192 participants; 4 studies; very low-quality evidence) were lower with low central venous pressure than with control. For the other comparisons, the evidence for difference was either based on single small trials or there was no evidence of differences. None of the trials reported health-related quality of life or time needed to return to work.

AUTHORS' CONCLUSIONS

Paucity of data meant that we could not assess transitivity assumptions and inconsistency for most analyses. When direct and indirect comparisons were available, network meta-analysis provided additional effect estimates for comparisons where there were no direct comparisons. However, the paucity of data decreases the confidence in the results of the network meta-analysis. Low-quality evidence suggests that liver resection using a radiofrequency dissecting sealer may be associated with more adverse events than with the clamp-crush method. Low-quality evidence also suggests that the proportion of people requiring a blood transfusion is higher with low central venous pressure than with acute normovolemic haemodilution plus low central venous pressure; very low-quality evidence suggests that blood transfusion quantity (red blood cells) was lower with fibrin sealant than control; blood transfusion quantity (fresh frozen plasma) was higher with oxidised cellulose than with fibrin sealant; and blood loss, total hospital stay, and operating time were lower with low central venous pressure than with control. There is no evidence to suggest that using special equipment for liver resection is of any benefit in decreasing the mortality, morbidity, or blood transfusion requirements (very low-quality evidence). Radiofrequency dissecting sealer should not be used outside the clinical trial setting since there is low-quality evidence for increased harm without any evidence of benefits. In addition, it should be noted that the sample size was small and the credible intervals were wide, and we cannot rule out considerable benefit or harm with a specific method of liver resection.

Hemostasis and Hepatic Surgery

Operative blood loss is a major source of morbidity and even mortality for patients undergoing hepatic resection. This review discusses strategies to minimize blood loss and the utilization of allogeneic blood transfusion pertaining to oncologic hepatic surgery.

The impact of intraoperative vascular occlusion during liver surgery on postoperative peak ALT levels: A systematic review and meta-analysis

BACKGROUND AND AIMS

Intraoperative vascular occlusion techniques during liver surgeries have been performed and refined for decades. However, the impact of these techniques on postoperative peak ALT levels remains uncertain. Thus, we performed a literature review and meta-analysis to determine the impact of intraoperative vascular occlusion during liver surgery on postoperative peak ALT levels.

METHODS

A systematic literature search of the PubMed database was conducted to discover relevant controlled clinical trials. Studies that reported postoperative peak ALT values for both an observation group and a control group were included. The Q statistic and the I(2) index statistic were used to assess heterogeneity. Publication bias was evaluated using Egger's test and Orwin's fail-safe N test.

RESULTS

Of the 281 retrieved articles, 10 articles fulfilled the inclusion criteria. These 10 articles involved 12 randomized controlled trials with a total of 1443 records. The pooled estimation results indicated that intraoperative vascular occlusion significantly elevated postoperative peak ALT levels (test for SMD: Z = 4.09, P < 0.001; 95% CI: 0.59-1.68), with high heterogeneity (I(2) = 93.8%). Subgroup analysis revealed that intermittent inflow occlusion and Pringle's maneuver vascular occlusions may be the potential crucial factors. No obvious publication bias was detected by Egger's test (P = 0.541) or Orwin's fail-safe N test (Nfs0.05 = 2059.19).

CONCLUSIONS

Intraoperative vascular occlusion, especially intermittent inflow occlusion and Pringle's maneuver vascular occlusions, may be a potential risk factor that could lead higher postoperative peak ALT values than non-occlusion procedures for liver surgeries.

Macrosteatotic and nonmacrosteatotic grafts respond differently to intermittent hepatic inflow occlusion: Comparison of recipient survival

Intermittent hepatic inflow occlusion (IHIO) during liver graft procurement is known to confer protection against graft ischemia/reperfusion injury and thus may benefit the recipient's outcome. We evaluated whether the protective effect of IHIO differs with the presence of macrosteatosis (MaS) and with an increase or decrease in the cumulative occlusion time. The subgroup of 188 recipients who received grafts with MaS was divided into 3 groups according to the number of total IHIO rounds during graft procurement: no IHIO, n = 70; 1 to 2 rounds of IHIO, n = 50; and ≥3 rounds of IHIO, n = 68. Likewise, the subgroup of 200 recipients who received grafts without MaS was divided into 3 groups: no IHIO, n = 108; 1 to 2 rounds of IHIO, n = 40; and ≥3 rounds of IHIO, n = 52. The Cox model was applied to evaluate the association between the number of total IHIO rounds and recipient survival separately in the subgroup of MaS recipients and the subgroup of non-MaS recipients. Analyzed covariables included the etiology, Milan criteria, transfusion, immunosuppression, and others. In the subgroup of MaS recipients, 1 to 2 rounds of IHIO were favorably associated with recipient survival [hazard ratio (HR), 0.29; 95% confidence interval (CI), 0.10-0.80; P = 0.03 after Bonferroni correction], whereas ≥3 rounds of IHIO were not associated with recipient survival (HR, 0.56; 95% CI, 0.25-1.23). In the subgroup of non-MaS recipients, neither 1 to 2 rounds of IHIO (HR, 0.69; 95% CI, 0.30-1.61) nor ≥3 rounds of IHIO (HR, 0.91; 95% CI, 0.42-1.96) were associated with recipient survival. In conclusion, 1 to 2 rounds of IHIO may be used for the procurement of MaS grafts with potential benefit for recipient survival, whereas IHIO has a limited impact on recipient survival regardless of the cumulative occlusion time when it is used for non-MaS grafts.

Glycemic responses to intermittent hepatic inflow occlusion in living liver donors

The occurrence of glycemic disturbances has been described for patients undergoing intermittent hepatic inflow occlusion (IHIO) for tumor removal. However, the glycemic responses to IHIO in living liver donors are unknown. This study investigated the glycemic response to IHIO in these patients and examined the association between this procedure and the occurrence of hyperglycemia (blood glucose > 180 mg/dL). The data from 154 living donors were retrospectively reviewed. The decision to perform IHIO was made on the basis of the extent of bleeding that occurred during parenchymal dissection. One round of IHIO consisted of 15 minutes of clamping and 5 minutes of unclamping the hepatic artery and portal vein. Blood glucose concentrations were measured at predetermined time points, including the start and end of IHIO. Repeated hyperglycemic episodes occurred after unclamping. The mean maximum intraoperative blood glucose concentration was greater in donors who underwent ≥3 rounds of IHIO versus those who underwent 1 or 2 rounds (169 ± 30 versus 149 ± 31 mg/dL, P = 0.005). The incidence of intraoperative hyperglycemia was also greater in donors who underwent ≥3 rounds of IHIO versus those who underwent 1 or 2 rounds (38.7% versus 7.7%, odds ratio = 7.1, 95% confidence interval = 2.5-20.4, P < 0.001). Donors who did not undergo IHIO and those who underwent 1 or 2 rounds of IHIO exhibited similar maximum glucose concentrations and similar incidence rates of hyperglycemia. In conclusion, IHIO induced repeated hyperglycemic responses in living donors, and donors who underwent ≥3 rounds of IHIO were more likely to experience intraoperative hyperglycemia. These results provide additional information on the risks and benefits of IHIO in living donors.

Intraoperative hyperglycemia during liver resection: predictors and association with the extent of hepatocytes injury

Background

Patients undergoing liver resection are at risk for intraoperative hyperglycemia and acute hyperglycemia is known to induce hepatocytes injury. Thus, we aimed to evaluate whether intraoperative hyperglycemia during liver resection is associated with the extent of hepatic injury.

Methods

This 1 year retrospective observation consecutively enrolled 85 patients undergoing liver resection for hepatocellular carcinoma. Blood glucose concentrations were measured at predetermined time points including every start/end of intermittent hepatic inflow occlusion (IHIO) via arterial blood analysis. Postoperative transaminase concentrations were used as surrogate parameters indicating the extent of surgery-related acute hepatocytes injury.

Results

Thirty (35.5%) patients developed hyperglycemia (blood glucose > 180 mg/dl) during surgery. Prolonged (≥ 3 rounds) IHIO (odds ratio [OR] 7.34, P = 0.004) was determined as a risk factors for hyperglycemia as well as cirrhosis (OR 4.07, P = 0.022), lower prothrombin time (OR 0.01, P = 0.025), and greater total cholesterol level (OR 1.04, P = 0.003). Hyperglycemia was independently associated with perioperative increase in transaminase concentrations (aspartate transaminase, β 105.1, standard error 41.7, P = 0.014; alanine transaminase, β 81.6, standard error 38.1, P = 0.035). Of note, blood glucose > 160 or 140 mg/dl was not associated with postoperative transaminase concentrations.

Conclusions

Hyperglycemia during liver resection might be associated with the extent of hepatocytes injury. It would be rational to maintain blood glucose concentration < 180 mg/dl throughout the surgery in consideration of parenchymal disease, coagulation status, lipid profile, and the cumulative hepatic ischemia in patients undergoing liver resection for hepatocellular carcinoma.

Ischemic preconditioning provides no additive clinical value in liver resection of cirrhotic and non-cirrhotic patients under portal triad clamping: a prospective randomized controlled trial

BACKGROUND AND OBJECTIVE

The clinical value of ischemic preconditioning (IP) on patients undergoing hepatectomy under portal triad clamping (PTC) is uncertain, especially for patients with liver cirrhosis. Hence, we conducted a prospective randomized controlled trial to test whether IP could protect liver against ischemic reperfusion (IR) injury after hepatectomy under PTC.

METHOD

One hundred patients, including 67 with cirrhosis, undergoing hepatectomy with PTC were randomly divided into IP and control groups. Liver function tests at postoperative days 1, 3, and 7 as well as postoperative morbidity, mortality, and duration of hospitalization were compared between the two groups.

RESULTS

The general clinical characteristics between both groups were comparable. The duration of the operation, the amount of intraoperative blood loss, and the need and amount of perioperative blood transfusion were similar in both groups. The postoperative levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin, and albumin were not statistically different between the two groups. In addition, the morbidity and mortality rates and the duration of hospitalization were similar in both groups.

CONCLUSIONS

IP did not improve liver tolerance to IR injury after hepatectomy under PTC. Therefore, the clinical use of IP cannot be recommended as a standard procedure before PTC.

Comparison of the tolerance of hepatic ischemia/reperfusion injury in living donors: macrosteatosis versus microsteatosis

A safe use of intermittent hepatic inflow occlusion (IHIO) has been reported for living donor hepatectomy. However, it remains unclear whether the maneuver is safe in steatotic donors. In addition, the respective importance of macrosteatosis (MaS) and microsteatosis (MiS) is an important issue. Thus, we compared MiS and MaS with respect to the tolerance of hepatic ischemia/reperfusion (IR) injury induced by IHIO. One hundred forty-four donors who underwent a right hepatectomy were grouped according to the presence of MaS and MiS: a non-MaS group (n = 68) versus an MaS group (n = 76) and a non-MiS group (n = 51) versus an MiS group (n = 93). The coefficients of the regression lines between the cumulative IHIO time and the peak postoperative transaminase concentrations were used as surrogate parameters indicating the tolerance of hepatic IR injury. The coefficients were significantly greater for the MaS group versus the non-MaS group (4.12 ± 0.59 versus 2.22 ± 0.46 for alanine aminotransferase, P = 0.01). Conversely, the MiS and non-MiS groups were comparable. A subgroup analysis of donors who underwent IHIO for >30 minutes showed that MaS significantly increased the transaminase concentrations, whereas MiS had no impact. Also, IHIO for >30 minutes significantly increased the biliary complication rate for MaS donors (12.1% for ≤ 30 minutes versus 32.6% for >30 minutes, P = 0.04), whereas MiS donors were not affected. In conclusion, the tolerance of hepatic IR injury might differ between MaS livers and MiS livers. It would be rational to assign more clinical importance to MaS versus MiS. We further recommend limiting the cumulative IHIO time to 30 minutes or less for MaS donors undergoing right hepatectomy.

Systematic review of pathophysiological changes following hepatic resection

OBJECTIVES

Major hepatic resection is now performed frequently and with relative safety, but is accompanied by significant pathophysiological changes. The aim of this review is to describe these changes along with interventions that may help reduce the risk for adverse outcomes after major hepatic resection.

METHODS

The MEDLINE, EMBASE and CENTRAL databases were searched for relevant literature published from January 2000 to December 2011. Broad subject headings were 'hepatectomy/', 'liver function/', 'liver failure/' and 'physiology/'.

RESULTS

Predictable changes in blood biochemistry and coagulation occur following major hepatic resection and alterations from the expected path indicate a complicated course. Susceptibility to sepsis, functional renal impairment, and altered energy metabolism are important sequelae of post-resection liver failure.

CONCLUSIONS

The pathophysiology of post-resection liver failure is difficult to reverse and thus strategies aimed at prevention are key to reducing morbidity and mortality after liver surgery.

Methods to decrease blood loss during liver resection: a network meta-analysis

BACKGROUND

Liver resection is a major surgery with significant mortality and morbidity. Various methods have been attempted to decrease blood loss and morbidity during elective liver resection. These methods include different methods of vascular occlusion, parenchymal transection, and management of the cut surface of the liver. A surgeon typically uses only one of the methods from each of these three categories. Together, one can consider this combination as a treatment strategy. The optimal treatment strategy for liver resection is unknown.

OBJECTIVES

To assess the comparative benefits and harms of different treatment strategies that aim to decrease blood loss during elective liver resection.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and Science Citation Index Expanded to July 2012 to identify randomised clinical trials. We also handsearched the references lists of identified trials.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or publication status) where the method of vascular occlusion, parenchymal transection, and management of the cut surface were clearly reported, and where people were randomly assigned to different treatment strategies based on different combinations of the three categories (vascular occlusion, parenchymal transection, cut surface).

DATA COLLECTION AND ANALYSIS

Two review authors identified trials and collected data independently. We assessed the risk of bias using The Cochrane Collaboration's methodology. We conducted a Bayesian network meta-analysis using the Markov chain Monte Carlo method in WinBUGS 1.4 following the guidelines of the National Institute for Health and Care Excellence Decision Support Unit guidance documents. We calculated the odds ratios (OR) with 95% credible intervals (CrI) (which are similar to confidence intervals in the frequentist approach for meta-analysis) for the binary outcomes and mean differences (MD) with 95% CrI for continuous outcomes using a fixed-effect model or random-effects model according to model-fit.

MAIN RESULTS

We identified nine trials with 617 participants that met our inclusion criteria. Interventions in the trials included three different options for vascular occlusion, four for parenchymal transection, and two for management of the cut liver surface. These interventions were combined in different ways in the trials giving 11 different treatment strategies. However, we were only able to include 496 participants randomised to seven different treatment strategies from seven trials in our network meta-analysis, because the treatment strategies from the trials that used fibrin sealant for management of the raw liver surface could not be connected to the network for any outcomes. Thus, the trials included in the network meta-analysis varied only in their approaches to vascular exclusion and parenchymal transection and none used fibrin sealant. All the trials were of high risk of bias and the quality of evidence was very low for all the outcomes. The differences in mortality between the different strategies was imprecise (seven trials; seven treatment strategies; 496 participants). Five trials (six strategies; 406 participants) reported serious adverse events. There was an increase in the proportion of people with serious adverse events when surgery was performed using radiofrequency dissecting sealer compared with the standard clamp-crush method in the absence of vascular occlusion and fibrin sealant. The OR for the difference in proportion was 7.13 (95% CrI 1.77 to 28.65; 15/49 (adjusted proportion 24.9%) in radiofrequency dissecting sealer group compared with 6/89 (6.7%) in the clamp-crush method). The differences in serious adverse events between the other groups were imprecise. There was a high probability that 'no vascular occlusion with clamp-crush method and no fibrin' and 'intermittent vascular occlusion with Cavitron ultrasonic surgical aspirator and no fibrin' are better than other treatments with regards to serious adverse events. Quality of life was not reported in any of the trials.The differences in the proportion of people requiring blood transfusion was imprecise (six trials; seven treatments; 446 participants). Two trials (three treatments; 155 participants) provided data for quantity of blood transfused. People undergoing liver resection by intermittent vascular occlusion had higher amounts of blood transfused than people with continuous vascular occlusion when the parenchymal transection was carried out with the clamp-crush method and no fibrin sealant was used for the cut surface (MD 1.2 units; 95% CrI 0.08 to 2.32). The differences in the other comparisons were imprecise (very low quality evidence). Three trials (four treatments; 281 participants) provided data for operative blood loss. People undergoing liver resection using continuous vascular occlusion had lower blood loss than people with no vascular occlusion when the parenchymal transection was carried out with clamp-crush method and no fibrin sealant was used for the cut surface (MD -130.9 mL; 95% CrI -255.9 to -5.9). None of the trials reported the proportion of people with major blood loss.The differences in the length of hospital stay (six trials; seven treatments; 446 participants) and intensive therapy unit stay (four trials; six treatments; 261 participants) were imprecise. Four trials (four treatments; 245 participants) provided data for operating time. Liver resection by intermittent vascular occlusion took longer than liver resection performed with no vascular occlusion when the parenchymal transection was carried out with Cavitron ultrasonic surgical aspirator and no fibrin sealant was used for the cut surface (MD 49.6 minutes; 95% CrI 29.8 to 69.4). The differences in the operating time between the other comparisons were imprecise. None of the trials reported the time needed to return to work.

AUTHORS' CONCLUSIONS

Very low quality evidence suggested that liver resection using a radiofrequency dissecting sealer without vascular occlusion or fibrin sealant may increase serious adverse events and this should be evaluated in further randomised clinical trials. The risk of serious adverse events with liver resection using no special equipment compared with more complex methods requiring special equipment was uncertain due to the very low quality of the evidence. The credible intervals were wide and considerable benefit or harm with a specific method of liver resection cannot be ruled out.

Actual incidence and long-term consequences of posthepatectomy liver failure after hepatectomy for colorectal liver metastases

INTRODUCTION

Posthepatectomy liver failure (PHLF) is a severe complication after hepatectomy for colorectal liver metastases. This study evaluated its actual incidence and its effects on short- and long-term overall survival (OS) in a specialized center.

MATERIALS AND METHODS

Between 2006 and 2008, 193 patients who underwent 232 hepatectomies (147 minor and 85 major) for colorectal liver metastasis were studied prospectively. Hepatectomy was performed if the remnant liver volume was >0.5% of body weight. Uni- and multivariate analyses on OS after all hepatectomies (n = 232) or major resection only (n = 85) were then performed on pre-, intra-, and postoperative (including pathological) data to determine the consequences of PHLF by comparison with those of other intra- and postoperative events.

RESULTS

The 3-month postoperative mortality rate was 0.8%. PHLF was observed in six patients (7%) after major hepatectomy and in one (0.6%) after minor hepatectomy. With a 25-month follow-up, the 2-year OS rate was 84%. Preoperatively, pulmonary metastasis was the only determinant of OS. Intra- and postoperatively, four factors were determinant of OS: PHLF (risk ratio [RR] = 3.84, P = .04), mental confusion (RR = 3.11, P = .006), fluid collection (RR = 2.9, P = .01) and transfusion (RR = 2.27, P = .009). After major hepatectomy, only PHLF (RR = 4.14, P = .01) and confusion (RR = 3.6, P = .02) were identified.

CONCLUSION

With improvements in postoperative management, PHLF was found to be less responsible for 3-month mortality but remains an event that exerts a major impact on 2-year survival.

Meta-analysis of intermittent Pringle manoeuvre versus no Pringle manoeuvre in elective liver surgery

BACKGROUND AND OBJECTIVES

Intermittent Pringle manoeuvre (IPM) is frequently used during liver surgery. This meta-analysis aimed to review the impact on blood loss, operating time and morbidity and mortality with and without use of IPM.

METHODS

An electronic search was performed of the MEDLINE, EMBASE, PubMed databases using both subject headings (MeSH) and truncated word searches to identify all articles published that related to this topic. Pooled risk ratios were calculated for categorical outcomes, and mean differences (MDs) for secondary continuous outcomes, using the fixed-effects and random-effects models for meta-analysis.

RESULTS

Four randomized controlled trials encompassing 392 patients were analysed to achieve a summated outcome. Pooled data analysis showed the use of IPM resulted in reduced transection time/cm(2) (MD -0.53 (-0.88, -0.18) min/cm(2) (P = 0.003)) but with comparable blood loss (mL/cm(2)) (MD -1.67 (-4.41, 1.08) mL/cm(2), P = 0.23), overall blood loss (MD -20.42 (-89.42, 48.58) mL), blood transfusion requirements (risk ratio 0.78 (0.40, 1.52, P = 0.47)) and morbidity and mortality compared to no Pringle manoeuvre. In addition, there was no significant difference in the post-operative hospital stay (MD 0.37 (-0.60, 1.34) days).

CONCLUSIONS

There is no evidence that the routine use of IPM improves perioperative and post-operative outcomes compared to no Pringle manoeuvre and its routine may not be recommended.

Surrogate endpoints in liver surgery related trials: a systematic review of the literature

BACKGROUND

Although the safety of liver surgery has improved enormously, hepatic surgery continues to face challenging complications. Therefore, improvements supported by evidence-based guidelines are still required. The conduct of randomized controlled trials in liver surgery using dichotomous outcomes requires a large sample size. The use of surrogate endpoints (SEPs) reduces sample size but SEPs should be validated before use.

AIM

The aim of this review was to summarize the SEPs used in hepatic surgery related trials, their definitions and recapitulating the evidence validating their use.

METHOD

A systematic computerized literature search in the biomedical database PubMed using the MeSH terms 'hepatectomy' or 'liver resection' or 'liver transection' was conducted. Search was limited to papers written in the English language and published between 1 January 2000 and 1 January 2010.

RESULTS

A total of 593 articles met the search terms and 49 articles were included in the final selection. Standard biochemical liver functions tests were the most frequently used SEP (32 of 49 the studies). The used definitions of SEPs varied greatly among the studies. Most studies referred to earlier published material to justify their choice of SEP. However, no validating studies were found.

CONCLUSION

Many SEPs are used in liver surgery trials however there is little evidence validating them.

Right hepatectomy with extra-hepatic vascular division prior to transection: intention-to-treat analysis of a standardized policy

BACKGROUND

Right hepatectomy (RH) is the most common type of major hepatectomy and can be achieved without portal triad clamping (PTC) in non-cirrhotic liver. The present study reviews our standardized policy of performing RH without systematic PTC.

METHODS

One hundred and eighty-one consecutive RH were performed in non-cirrhotic patients, with division of the right afferent and efferent blood vessels prior to transection, without systematically using PTC. Prospectively collected data were analysed, focusing on the following endpoints: need for salvage PTC, ischaemic time, blood loss and post-operative outcome.

RESULTS

Extra-hepatic division of the right hepatic vessels was feasible in all patients, but was ineffective in 48 patients (26.5%) who required salvage PTC during transection. In those patients, the median ischaemic time was 20 min. The median blood loss was 500 ml (50-3000). Six patients (3.3%) experienced post-operative liver failure. Overall morbidity, severe morbidity and mortality were 42%, 12.1% and 1.6%, respectively, with peri-operative transfusion rate (16.6%) being the only factor associated with morbidity.

DISCUSSION

By performing RH with extra-hepatic vascular division prior to transection, PTC can be safely avoided in the majority of patients.

Randomized clinical trial of open hepatectomy with or without intermittent Pringle manoeuvre

BACKGROUND

The intermittent Pringle manoeuvre (IPM) is commonly applied during liver resection. Few randomized trials have addressed its effectiveness in reducing blood loss and the results have been conflicting. The present study investigated the hypothesis that IPM could reduce blood loss during liver resection by 50 per cent.

METHODS

Between May 2008 and April 2011, patients who underwent elective open hepatectomy were randomized into an IPM or no Pringle manoeuvre (NPM) group and stratified according to the presence or absence of cirrhosis. Data on demographics, type of hepatectomy, operative blood loss, duration of operation, mortality, morbidity and postoperative liver function were recorded and analysed. The primary endpoint was operative blood loss.

RESULTS

There were 63 patients in each group. Median (range) operative blood loss was 370 (50-3600) ml in the IPM group versus 335 (40-3160) ml in the NPM group (P = 1·000). There were no differences in blood loss in different phases of the operation, blood loss per area of liver transected or blood transfusion rate, nor in total duration of operation or liver transection time. Postoperative serum alanine aminotransferase levels were higher in the IPM group (P < 0·001). There were more postoperative complications in the IPM group (41 versus 24 per cent; P = 0·036).

CONCLUSION

The IPM did not reduce blood loss, but was associated with raised levels of postoperative liver parenchymal enzymes and more complications.

REGISTRATION NUMBER

NCT00730743 (http://www.clinicaltrials.gov).

Portal triad clamping versus other methods of vascular control in liver resection: a systematic review and meta-analysis

BACKGROUND

Portal triad clamping (PTC) is the most commonly used method of achieving vascular control during liver resection. However, the efficacy and safety of PTC, compared with those of other methods of vascular control, are uncertain.

METHODS

A systematic review was conducted to identify randomized controlled trials (RCTs) comparing PTC with other methods of vascular control during liver resection. Endpoints included in-hospital mortality, need for transfusion, number of complications and length of hospital stay. Meta-analyses were performed using a random-effects model.

RESULTS

Ten RCTs were identified; these included a total of 820 patients. No statistically significant differences between PTC and other forms of vascular control in liver resection were demonstrated.

CONCLUSIONS

There is no evidence, on the basis of this meta-analysis of RCTs, of any difference between PTC and other forms of vascular control in liver resection.

Anesthetic Considerations in Hepatectomies under Hepatic Vascular Control

Background. Hazards of liver surgery have been attenuated by the evolution in methods of hepatic vascular control and the anesthetic management. In this paper, the anesthetic considerations during hepatic vascular occlusion techniques were reviewed. Methods. A Medline literature search using the terms "anesthetic," "anesthesia," "liver," "hepatectomy," "inflow," "outflow occlusion," "Pringle," "hemodynamic," "air embolism," "blood loss," "transfusion," "ischemia-reperfusion," "preconditioning," was performed. Results. Task-orientated anesthetic management, according to the performed method of hepatic vascular occlusion, ameliorates the surgical outcome and improves the morbidity and mortality rates, following liver surgery. Conclusions. Hepatic vascular occlusion techniques share common anesthetic considerations in terms of preoperative assessment, monitoring, induction, and maintenance of anesthesia. On the other hand, the hemodynamic management, the prevention of vascular air embolism, blood transfusion, and liver injury are plausible when the anesthetic plan is scheduled according to the method of hepatic vascular occlusion performed.

Randomized controlled trial analyzing the effect of 15 or 30 min intermittent Pringle maneuver on hepatocellular damage during liver surgery

BACKGROUND & AIMS

Aminotransferases are commonly used to determine the optimal duration of ischemic intervals during intermittent Pringle maneuver (IPM). However, they might not be responsive enough to detect small differences in hepatocellular damage. Liver fatty acid-binding protein (L-FABP) has been suggested as a more sensitive marker. This randomized trial aimed to compare hepatocellular injury reflected by L-FABP in patients undergoing liver resection with IPM using 15 or 30 min ischemic intervals.

METHODS

Twenty patients undergoing liver surgery were randomly assigned to IPM with 15 (15IPM) or 30 (30IPM) minutes ischemic intervals. Ten patients not requiring IPM (noIPM) served as controls. Primary endpoint was hepatocellular injury during liver surgery reflected by systemic L-FABP plasma levels. Between group comparisons were performed using area under the curve and repeated measures two-way ANOVA.

RESULTS

The IPM groups had similar characteristics. Aminotransferases did not differ significantly between 15IPM and 30IPM at any time point. L-FABP levels rose up to 1853±708 ng/ml in the 15IPM and 3662±1355 ng/ml in the 30IPM group after finishing liver transection and decreased rapidly thereafter. There were no significant differences between 15IPM and 30IPM in cumulative L-FABP level (p=0.378) or L-FABP level at any time point (p=0.149). Blood loss, remnant liver function and morbidity were comparable.

CONCLUSIONS

IPM with 15 or 30 min ischemic intervals induced similar hepatocellular injury measured by the sensitive marker L-FABP. The present study confirms the results of earlier trials, suggesting that IPM with 30 min ischemic intervals may be used.

High-intensity focused ultrasound (HIFU)-assisted hepatic resection in an animal model

BACKGROUND

Bleeding is the main cause of postoperative complications of hepatic surgery. To minimize intraoperative bleeding during hepatectomy, resections are generally carried out under hepatic vascular control despite the risk of liver dysfunction in patients with chronic liver disease. This study evaluates the feasibility and safety of high-intensity focused ultrasound (HIFU)-assisted hepatic resection during an open procedure in an animal model.

METHODS

Three groups of 12-14-week-old Landrace pigs (n = 7/group) were used to evaluate HIFU-assisted liver resection (group A) vs liver resection with or without portal triad clamping (groups B and C). In each pig, liver resection was performed on the right and left paramedian lobes. The following were evaluated and compared in the 3 groups: total blood loss, blood loss/cm(2) of resection area, clip density, procedure duration, morbidity, and mortality.

RESULTS

Median blood loss was significantly lower in group A than in group B (P = .02), and group C (P = .007). Median blood loss/cm(2) of resection area was 4.77 mL/cm² in group A, 11.35 mL/cm² in group B, 12.22 mL/cm² in Group C. Precoagulation resulted in sealing blood vessels <5 mm; therefore, median clip density during liver transection was 0.78 clip/cm² in group A, 1.61 clip/cm(2) in group B, and 1.57 clip/cm(2) in group C. Median duration of the surgical procedure was 12 min in group A, 21 min in group B, and 19 min in group C.

CONCLUSIONS

HIFU-assisted hepatic resection during an open procedure in an animal model is safe, reduces bleeding, and allows real-time ultrasound guidance.

Hepatic blood inflow occlusion without hemihepatic artery control in treatment of hepatocellular carcinoma

AIM: To investigate the clinical significance of hepatic blood inflow occlusion without hemihepatic artery control (BIOwHAC) in the treatment of hepatocellular carcinoma (HCC).

METHODS: Fifty-nine patients with HCC were divided into 3 groups based on the technique used for achieving hepatic vascular occlusion: group 1, vascular occlusion was achieved by the Pringle maneuver (n = 20); group 2, by hemihepatic vascular occlusion (HVO) (n = 20); and group 3, by BIOwHAC (n = 19). We compared the procedures among the three groups in term of operation time, intraoperative bleeding, postoperative liver function, postoperative complications, and length of hospital stay.

RESULTS: There were no statistically significant differences (P > 0.05) in age, sex, pathological diagnosis, preoperative Child’s disease grade, hepatic function, and tumor size among the three groups. No intraoperative complications or deaths occurrred, and there were no significant intergroup differences (P > 0.05) in intraoperative bleeding, hepatic function change 3 and 7 d after operation, the incidence of complications, and length of hospital stay. BIOwHAC and Pringle maneuver required a significantly shorter operation time than HVO; the difference in the serum alanine aminotransferase or aspartate aminotransferase levels before and 1 d after operation was more significant in the BIOwHAC and HVO groups than in the Pringle maneuver group (P < 0.05).

CONCLUSION: BIOwHAC is convenient and safe; this technique causes slight hepatic ischemia-reperfusion injury similar to HVO.

IVC CLAMP: infrahepatic inferior vena cava clamping during hepatectomy--a randomised controlled trial in an interdisciplinary setting

BACKGROUND

Intraoperative haemorrhage is a known predictor for perioperative outcome of patients undergoing hepatic resection. While anaesthesiological lowering of central venous pressure (CVP) by fluid restriction is known to reduce bleeding during transection of the hepatic parenchyma its potential side effects remain poorly investigated. In theory it may have negative effects on kidney function and tissue perfusion and bears the risk to result in severe haemodynamic instability in case of profound intraoperative blood loss. The present randomised controlled trial evaluates efficacy and safety of infrahepatic inferior vena cava (IVC) clamping as an alternative surgical technique to reduce CVP during hepatic resection.

METHODS/DESIGN

The proposed IVC CLAMP trial is a single-centre randomised controlled trial with a two-group parallel design. Patients and outcome-assessors are blinded for the treatment intervention. Patients undergoing elective hepatic resection due to any reason are enrolled in IVC CLAMP. All patients admitted to the Department of General-, Visceral-, and Transplant Surgery, University of Heidelberg for elective hepatic resection are consecutively screened for eligibility and written informed consent is obtained on the day before surgery. The primary objective of this trial is to assess and compare the amount of blood loss during hepatic resection in patients receiving surgical CVP reduction by clamping of the IVC as compared to anaesthesiological CVP without infrahepatic IVC clamping reduction. In addition to blood loss a set of general as well as surgical variables are analysed.

DISCUSSION

This is a randomised controlled patient and observer blinded two-group parallel trial designed to assess efficacy and safety of infrahepatic IVC clamping during elective hepatectomy.

Clamping techniques and protecting strategies in liver surgery

The use of vascular occlusion during liver resection is still a matter of debate. The aim of this review was to assess the advantages and disadvantages of portal triad occlusion as a protective strategy during elective liver resection and liver transplantation. Newer strategies such as pharmacological preconditioning are also discussed. A systematic literature search was conducted to detect randomized controlled trials assessing the effectiveness and safety of portal triad clamping, ischaemic preconditioning and pharmacological preconditioning during liver surgery. Vascular clamping cannot be systematically recommended. When used, portal triad clamping is associated with a tendency towards reduced blood loss and blood transfusion without having an impact on morbidity. Intermittent clamping appears to be better tolerated than continuous clamping, especially in patients with chronic liver disease. Ischaemic preconditioning before continuous portal triad clamping reduces reperfusion injury after warm ischaemia, particularly in steatotic patients. Ischaemic preconditioning has unclear effects in transplantation and there is currently no evidence to support or refute the use of ischaemic preconditioning in the donor. There are emerging alternative conditioning strategies, including the use of volatile anaesthetics, which may provide new and easily applicable therapeutic options to protect the liver.

WITHDRAWN: Methods of vascular occlusion for elective liver resections

BACKGROUND

Vascular occlusion is used to reduce blood loss during liver resection surgery. There is considerable controversy regarding whether vascular occlusion should be used or not during elective liver resections. The method of vascular occlusion employed is also controversial. There is also considerable debate on the role of ischaemic preconditioning before vascular occlusion.

OBJECTIVES

To assess the advantages (decreased blood loss and peri-operative morbidity) and disadvantages (liver dysfunction from ischaemia) of vascular occlusion during liver resections. To compare the advantages (in decreasing blood loss or decreasing ischaemia-reperfusion injury) and disadvantages of different types of vascular occlusion versus total, continuous portal triad clamping.

SEARCH STRATEGY

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until March 2007.

SELECTION CRITERIA

We included randomised clinical trials comparing vascular occlusion versus no vascular occlusion during elective liver resections (irrespective of language or publication status). We also included randomised clinical trials comparing the different methods of vascular occlusion and those investigating the role of ischaemic preconditioning in liver resection.

DATA COLLECTION AND ANALYSIS

We collected the data on the characteristics of the trial, methodological quality of the trials, mortality, morbidity, blood loss, blood transfusion requirements, liver function tests, markers of neutrophil activation, operating time, and hospital stay. We analysed the data with both the fixed-effect and the random-effects models using RevMan Analysis. For each binary outcome we calculated the odds ratio (OR) with 95% confidence intervals (CI) based on intention-to-treat analysis. For continuous outcomes, we calculated the weighted mean difference (WMD) with 95% confidence intervals.

MAIN RESULTS

We identified a total of 16 randomised trials. Five trials including 331 patients compared vascular occlusion (n = 166) versus no vascular occlusion (n = 165). Six trials including 521 patients compared different methods of vascular occlusion. Three trials including 210 patients compared ischaemic preconditioning before continuous portal triad clamping (n = 105) versus no ischaemic preconditioning (n = 105). Two trials including 127 patients compared ischaemic preconditioning before continuous portal triad clamping (n = 63) versus intermittent portal triad clamping (n = 64).The blood loss was significantly lower in vascular occlusion compared with no vascular occlusion. The liver enzymes were significantly elevated in the vascular occlusion group compared with no vascular occlusion. There was no difference in the mortality, liver failure, or other morbidities. Four of the five trials comparing vascular occlusion and no vascular occlusion used intermittent vascular occlusion. Trials comparing complete inflow and outflow occlusion to the liver, ie, hepatic vascular exclusion and portal triad clamping demonstrate significant detrimental haemodynamic changes in hepatic vascular exclusion compared to portal triad clamping. There was no significant difference in the number of units transfused and the number of patients needing transfusion. There was no difference in mortality, liver failure, or morbidity between total and selective methods of portal triad clamping. All four cases of mortality and liver failure in the comparison between the intermittent and continuous portal triad clamping occurred in the continuous portal triad clamping (statistically not significant). Intermittent portal triad clamping does not increase the total blood loss or operating time compared to continuous portal triad clamping.There was no statistically significant difference in the mortality, liver failure, morbidity, blood loss, or haemodynamic changes between ischaemic preconditioning versus no ischaemic preconditioning before continuous portal triad clamping. Liver enzymes used as markers of liver injury were significantly lower in the early post-operative period in the ischaemic preconditioning group. The intensive therapy unit stay and hospital stay were statistically significantly lower in the ischaemic preconditioning group than in the no ischaemic preconditioning group.There was no statistically significant difference in the mortality, liver failure, morbidity, intensive therapy unit stay, or hospital stay between ischaemic preconditioning before continuous portal triad clamping and intermittent portal triad clamping. The blood loss and transfusion requirements were lower in the ischaemic preconditioning group. Aspartate aminotransferase level was lower in the intermittent portal triad clamping group than the ischaemic preconditioning group on the third post-operative day. There was no difference in the peak aspartate aminotransferase levels or in the aspartate aminotransferase levels on first or sixth post-operative days of aspartate aminotransferase .

AUTHORS' CONCLUSIONS

Intermittent vascular occlusion seems safe in liver resection. However, it does not seem to decrease morbidity. Among the different methods of vascular occlusion, intermittent portal triad clamping has most evidence to support the clinical application. Hepatic vascular exclusion cannot be recommended routinely. Ischaemic preconditioning before continuous portal triad clamping may be of clinical benefit in reducing intensive therapy unit and hospital stay.

Vascular occlusion for elective liver resections

BACKGROUND

Vascular occlusion is used to reduce blood loss during liver resection. There is considerable controversy regarding whether vascular occlusion should be used or not during elective liver resections.

OBJECTIVES

To assess the advantages (decreased blood loss and peri-operative morbidity) and disadvantages (ischaemia-reperfusion injury related complications like liver dysfunction) of vascular occlusion during elective liver resections.

SEARCH STRATEGY

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until August 2008.

SELECTION CRITERIA

We included randomised clinical trials comparing vascular occlusion versus no vascular occlusion during elective liver resections (irrespective of language or publication status).

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trials for inclusion and independently extracted the data. We analysed the data with both the fixed-effect and the random-effects models using RevMan Analysis. We calculated the risk ratio (RR), mean difference (MD), or standardised mean difference (SMD) with 95% confidence intervals (CI) based on intention-to-treat or available case analysis.

MAIN RESULTS

We identified a total of five trials (of high bias-risk) which compared vascular occlusion (n = 166) versus no vascular occlusion (n = 165). Three of the five trials comparing vascular occlusion and no vascular occlusion used intermittent vascular occlusion. There was no difference in mortality, liver failure, or other morbidities. The blood loss was significantly lower in vascular occlusion compared with no vascular occlusion. The liver enzymes were significantly elevated in the vascular occlusion group compared with no vascular occlusion.

AUTHORS' CONCLUSIONS

Intermittent vascular occlusion seems safe in liver resection. However, it does not seem to decrease morbidity. More randomised trials seem to be needed.

Intermittent Pringle manoeuvre is not associated with adverse long-term prognosis after resection for colorectal liver metastases

BACKGROUND

Intermittent clamping of the porta hepatis, or the intermittent Pringle manoeuvre (IPM), is often used to control inflow during parenchymal liver transection. The aim of this study was to determine whether IPM is associated with an adverse long-term outcome after liver resection for colorectal liver metastasis (CRLM).

METHODS

All patients undergoing resection for CRLM in 1993-2006, for whom data on IPM were recorded, were included in the study. A total of 563 patients was available for analysis.

RESULTS

IPM was performed in 289 (51.3 per cent) of the patients. The duration of IPM ranged from 2 to 104 (median 22) min. There were no differences in clinicopathological features or postoperative morbidity between patients who had an IPM and those who did not. The median survival of patients undergoing IPM was 55.7 months compared with 48.9 months in those not having an IPM (P = 0.406). There was no difference in median disease-free survival between the two groups (22.1 versus 19.9 months respectively; P = 0.199).

CONCLUSION

IPM is not associated with an adverse long-term prognosis in patients undergoing liver resection for CRLM.

Systematic review and meta-analysis of the effect of portal triad clamping on outcome after hepatic resection

Background

The effect of portal triad clamping (PTC) on outcome after hepatic resection is uncertain.

Methods

A systematic literature search was conducted to detect randomized controlled trials (RCTs) assessing the effectiveness and safety of PTC alone and of PTC with ischaemic preconditioning (IPC) of the liver. Studies on clamping of the inferior vena cava or hepatic veins were excluded. Endpoints included postoperative overall morbidity and mortality, cardiopulmonary and hepatic morbidity, blood loss, transfusion rates and alanine aminotransferase (ALT) levels. Meta-analyses were performed using a random-effects model.

Results

Eight RCTs published between 1997 and 2006 containing a total of 558 patients were eligible for final analysis. The design of the identified studies varied considerably. Analyses of endpoints revealed no difference between intermittent PTC and no PTC. Meta-analyses of PTC with and without previous IPC revealed no differences, but postoperative ALT levels were significantly lower with IPC.

Conclusion

On currently available evidence, the routine use of PTC does not offer any benefit in perioperative outcome after liver resection. It cannot be recommended as a standard procedure.

Outcomes and prognostic factors of cirrhotic patients with hepatocellular carcinoma after radical major hepatectomy

BACKGROUND

Radical major hepatectomy (RMH) has been suggested as one of main options for cure of large/advanced hepatocellular carcinoma (HCC). However, its operative risk remains high and its effectiveness is still controversial, especially for patients with liver cirrhosis. The present study aims to investigate short- and long-term outcomes and to identify prognostic factors for cirrhotic patients with HCC after RMH.

MATERIALS AND METHODS

Prospectively collected clinicopathological data of 81 consecutive cirrhotic HCC patients who underwent RMH were reviewed retrospectively. The Kaplan-Meier method was adopted for evaluating long-term survival. Prognostic factors were identified by univariate and multivariate analyses.

RESULTS

After RMH, perioperative mortality, overall morbidity, and life-threatening morbidity were 1.2%, 24.7%, and 12.3%, respectively. Overall and disease-free 5-year survival rates were 39.4% and 28.1%, respectively. Univariate analysis showed that presence of portal vein tumor thrombosis (PVTT) and satellite nodules, late TNM staging, high Edmondson-Steiner grading, and blood transfusion was associated with worsened prognosis. Of them, Edmondson-Steiner grading was identified as the sole independent prognostic factor for both overall and disease-free survival by multivariate analysis, whereas blood transfusion and the presence of PVTT independently predicted unfavorable overall or disease-free survival, respectively.

CONCLUSIONS

These data indicated that RMH was safe and appeared to be effective in treating cirrhotic patients with HCC. Some tumor-related and clinical variables influenced long-term outcome of these patients after RMH.

Methods of vascular occlusion for elective liver resections

BACKGROUND

Vascular occlusion is used to reduce blood loss during liver resection surgery. There is considerable controversy regarding whether vascular occlusion should be used or not during elective liver resections. The method of vascular occlusion employed is also controversial. There is also considerable debate on the role of ischaemic preconditioning before vascular occlusion.

OBJECTIVES

To assess the advantages (decreased blood loss and peri-operative morbidity) and disadvantages (liver dysfunction from ischaemia) of vascular occlusion during liver resections. To compare the advantages (in decreasing blood loss or decreasing ischaemia-reperfusion injury) and disadvantages of different types of vascular occlusion versus total, continuous portal triad clamping.

SEARCH STRATEGY

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until March 2007.

SELECTION CRITERIA

We included randomised clinical trials comparing vascular occlusion versus no vascular occlusion during elective liver resections (irrespective of language or publication status). We also included randomised clinical trials comparing the different methods of vascular occlusion and those investigating the role of ischaemic preconditioning in liver resection.

DATA COLLECTION AND ANALYSIS

We collected the data on the characteristics of the trial, methodological quality of the trials, mortality, morbidity, blood loss, blood transfusion requirements, liver function tests, markers of neutrophil activation, operating time, and hospital stay. We analysed the data with both the fixed-effect and the random-effects models using RevMan Analysis. For each binary outcome we calculated the odds ratio (OR) with 95% confidence intervals (CI) based on intention-to-treat analysis. For continuous outcomes, we calculated the weighted mean difference (WMD) with 95% confidence intervals.

MAIN RESULTS

We identified a total of 16 randomised trials. Five trials including 331 patients compared vascular occlusion (n = 166) versus no vascular occlusion (n = 165). Six trials including 521 patients compared different methods of vascular occlusion. Three trials including 210 patients compared ischaemic preconditioning before continuous portal triad clamping (n = 105) versus no ischaemic preconditioning (n = 105). Two trials including 127 patients compared ischaemic preconditioning before continuous portal triad clamping (n = 63) versus intermittent portal triad clamping (n = 64). The blood loss was significantly lower in vascular occlusion compared with no vascular occlusion. The liver enzymes were significantly elevated in the vascular occlusion group compared with no vascular occlusion. There was no difference in the mortality, liver failure, or other morbidities. Four of the five trials comparing vascular occlusion and no vascular occlusion used intermittent vascular occlusion. Trials comparing complete inflow and outflow occlusion to the liver, ie, hepatic vascular exclusion and portal triad clamping demonstrate significant detrimental haemodynamic changes in hepatic vascular exclusion compared to portal triad clamping. There was no significant difference in the number of units transfused and the number of patients needing transfusion. There was no difference in mortality, liver failure, or morbidity between total and selective methods of portal triad clamping. All four cases of mortality and liver failure in the comparison between the intermittent and continuous portal triad clamping occurred in the continuous portal triad clamping (statistically not significant). Intermittent portal triad clamping does not increase the total blood loss or operating time compared to continuous portal triad clamping. There was no statistically significant difference in the mortality, liver failure, morbidity, blood loss, or haemodynamic changes between ischaemic preconditioning versus no ischaemic preconditioning before continuous portal triad clamping. Liver enzymes used as markers of liver injury were significantly lower in the early post-operative period in the ischaemic preconditioning group. The intensive therapy unit stay and hospital stay were statistically significantly lower in the ischaemic preconditioning group than in the no ischaemic preconditioning group. There was no statistically significant difference in the mortality, liver failure, morbidity, intensive therapy unit stay, or hospital stay between ischaemic preconditioning before continuous portal triad clamping and intermittent portal triad clamping. The blood loss and transfusion requirements were lower in the ischaemic preconditioning group. Aspartate aminotransferase level was lower in the intermittent portal triad clamping group than the ischaemic preconditioning group on the third post-operative day. There was no difference in the peak aspartate aminotransferase levels or in the aspartate aminotransferase levels on first or sixth post-operative days of aspartate aminotransferase.

AUTHORS' CONCLUSIONS

Intermittent vascular occlusion seems safe in liver resection. However, it does not seem to decrease morbidity. Among the different methods of vascular occlusion, intermittent portal triad clamping has most evidence to support the clinical application. Hepatic vascular exclusion cannot be recommended routinely. Ischaemic preconditioning before continuous portal triad clamping may be of clinical benefit in reducing intensive therapy unit and hospital stay.

Liver resective surgery: a multivariate analysis of postoperative outcome and complication

INTRODUCTION

Notwithstanding technical advances and high experience of liver resection of specialized centers, the rate of complications after surgical resection could be high. In this study, we analyzed causes and foreseeable risk factors linked to postoperative morbidity on the ground of data derived from a single center surgical population.

MATERIALS AND METHODS

From September 1989 to March 2005, 134 consecutive patients had liver resection for Hcc and 153 consecutive patients with liver metastasis (derived from either colorectal cancer or noncolorectal cancer) at our department. We performed 22 major hepatectomy, 20 left hepatectomy, 14 trisegmentectomy, 77 bisegmentectomy and/or left lobectomy, 74 segmentectomy, and 80 wedge resection.

RESULTS

In-hospital mortality rate was 4.5%, about 7% in Hcc cases and 2.6% in liver metastasis. Morbidity rate was 47.7%, caused by the rising of ascites (10%), temporary impairment liver function (19%), biliary fistula (6%), hepatic abscess (25%), hemoperitoneum (10%), and pleural effusion (30%) sometimes combined each other. Some variables, associated with the technical aspects of surgical procedure, are responsible of the rising of complication as: Pringle maneuver length of more than 20 minutes (p=0.001); the type of liver resection procedure [major hepatectomy (p=0.02), left hepatectomy (p=0.04), trisegmentectomy (p=0.04), bisegmentectomy and/or left lobectomy (p=0.04)]; and the request of an amount of blood transfusion of more than 600 cc (p=0.04). Also, both liver dysfunction, in particular Child A vs B and C (p=0.01), and histopathological grading (p=0.01) are associated with a high rate of postsurgical complication in Hcc cases.

CONCLUSION

We make the following recommendations: every liver resection should be planned after intraoperative ultrasonography, anatomical surgical procedure should be preferred instead of wedge resection, and modern devices should be used, like Argon Beam and Ligasure dissector, to reduce the incidence of both intraoperative and postoperative bleeding and biliary leakage.

Vascular control during hepatectomy: review of methods and results

The various techniques of hepatic vascular control are presented, focusing on the indications and drawbacks of each. Retrospective and prospective clinical studies highlight aspects of the pathophysiology, indications, and morbidity of the various techniques of hepatic vascular control. Newer perspectives on the field emerge from the introduction of ischemic preconditioning and laparoscopic hepatectomy. A literature review based on computer searches in Index Medicus and PubMed focuses mainly on prospective studies comparing techniques and large retrospective ones. All methods of hepatic vascular control can be applied with minimal mortality by experienced surgeons and are effective for controlling bleeding. The Pringle maneuver is the oldest and simplest of these methods and is still favored by many surgeons. Intermittent application of the Pringle maneuver and hemihepatic occlusion or inflow occlusion with extraparenchymal control of major hepatic veins is particularly indicated for patients with abnormal parenchyma. Total hepatic vascular exclusion is associated with considerable morbidity and hemodynamic intolerance in 10% to 20% of patients. It is absolutely indicated only when extensive reconstruction of the inferior vena cava (IVC) is warranted. Major hepatic veins/ and limited IVC reconstruction has been also achieved under inflow occlusion with extraparenchymal control of major hepatic veins or even using the intermittent Pringle maneuver. Ischemic preconditioning is strongly recommended for patients younger than 60 years and those with steatotic livers. Each hepatic vascular control technique has its place in liver surgery, depending on tumor location, underlying liver disease, patient cardiovascular status, and, most important, the experience of the surgical and anesthesia team.

Sharp liver transection versus clamp crushing technique in liver resections: A prospective study

BACKGROUND

Parenchymal liver transection constitutes an important phase of liver resection. Serious intraoperative bleeding, together with injuries to vital structures of the liver remnant, can occur during this stage. A method of sharp liver parenchymal transection with scalpel is compared in a prospective randomized manner with the widely used clamp crushing technique.

METHODS

Patients scheduled for hepatectomy under selective hepatic vascular exclusion (N = 82) were allocated randomly to either the sharp transection group (n = 41) or the clamp crushing group (n = 41). Warm ischemic time, blood loss and transfusions, postoperative morbidity and mortality, and tumor-free margins were recorded in both groups and analyzed.

RESULTS

When the sharp transection group was compared with the clamp crushing group, the two groups were similar in warm ischemic time (median 36 vs 34 minutes), total operative time (median 205 vs 211 minutes), intraoperative blood loss (median 500 vs 460 mL), blood transfusion requirements (median value 0 in both groups), and overall complication rate (44% vs 39%). However, sharp transection yielded better tumor-free margins compared with the clamp crushing technique (12 +/- 1.4 mm vs 8 +/- 1.5 mm, mean +/- SD, P < .05).

CONCLUSION

Sharp liver parenchymal transection with a scalpel is equally safe in terms of blood loss and mortality compared with the clamp crushing method. Although it is a technically demanding method, requiring selective hepatic vascular occlusion, it may be recommended when the tumor-free margins are anticipated to be narrow.

Early Stress Protein Gene Expression in a Human Model of Ischemic Preconditioning

Intermittent clamping of the porta hepatis (PHC) is commonly performed during liver surgery to reduce blood loss and has been reported to precondition livers resulting in improved outcome after liver surgery (humans) and transplantation (animals). This study investigated the early expression of cytoprotective stress proteins during ischemia-reperfusion induced by PHC. Liver samples were taken before and after each event in a two-cycle ischemia-reperfusion protocol using 15 minutes of PHC followed by 5 minutes of reperfusion. Liver tissue was analyzed by real-time polymerase chain reaction for heme oxygenase (HO)-1 and heat shock protein (HSP)-70 mRNA expression. Extracted protein was analyzed by Western blot for HO-1, and HSP-70 and nuclear extracts were analyzed by DNA mobility shift assay for hypoxia inducible factor (HIF)-1alpha and heat shock factor (HSF)-1. Within minutes of PHC, significant increases in HO-1 mRNA expression were detected, and these were maintained throughout the protocol (P < 0.01). Protein expression of HO-1 (P < 0.03) and HO-1 activity (P < 0.05) were similarly increased between the start and end of ischemia- reperfusion (40 minutes). Binding of active HIF-1alpha to its consensus sequence was increased within 15 minutes of the start of the ischemia-reperfusion cycle. Although evidence of the transcriptionally active form of HSF-1 was detected at the same time point, this was not reflected in measurable changes in HSP-70 mRNA or protein. In conclusion, expression of the cytoprotective protein HO-1 is significantly up-regulated in the liver within minutes of PHC. It is likely that HO-1 contributes to the early protective effects of ischemic preconditioning.