Relevance of Postoperative Peak Transaminase After Elective Hepatectomy

Protective Effect of Minimally Invasive Approach on Postoperative Peak Transaminase Following Liver Resection: A Single-Center Propensity Score-Based Analysis

BACKGROUND

Postoperative serum ALT levels are one of the most frequently used marker to detect liver tissue damage following liver resection. The aim of this study was to evaluate if minimally invasive liver surgery (MILS) may result in less hepatic injury than open hepatectomy by assessing the differences of postoperative ALT levels.

METHODS

Patients who underwent MILS between 2009 and 2019 at our unit were included and compared with open liver resections. Median ALT levels was measured on postoperative day (POD) 1, 3 and 5. Postoperative peak transaminase (PPT) of ALT was determined on POD 1. The stabilized inverse probability treatment weighing (SIPTW) process was used to balance the two groups. A multivariable logistic regression analysis was used to analyze factors associated with high PPT.

RESULTS

After SIPTW, 292 MILS were compared with 159 open resections. Median ALT levels on POD 1, 3 and 5 were significantly higher in the open group than in the MILS group (301 vs. 187, p = 0.002; 180 vs. 121, p < 0.0001; 104 vs. 60, p < 0.0001; respectively). At the multivariable logistic regression analysis, MILS showed a protective effect for high PPT.

CONCLUSIONS

MILS was associated with significantly lower postoperative ALT levels compared with open liver resections. MILS showed a protective effect for high PPT.

Remote ischemic preconditioning for reduction of ischemia-reperfusion injury after hepatectomy: A randomized sham-controlled trial

BACKGROUND

Remote ischemic preconditioning reduces ischemia-reperfusion injury in patients undergoing hepatectomy. Moreover, there is evidence that the protective effects of remote ischemic preconditioning may be more pronounced in pre-damaged livers. The objective of this trial was to investigate the extent to which remote ischemic preconditioning can attenuate ischemia-reperfusion injury after hepatectomy and Pringle maneuver in patients with chronic liver disease.

METHODS

In this randomized, controlled, triple-blind monocenter trial, a total of 102 patients with chronic liver disease and planned hepatectomy were enrolled between December 2019 and March 2022. Eligible patients were randomized to the remote ischemic preconditioning or sham arms. Remote ischemic preconditioning was induced through 3 10-minute cycles of alternating ischemia and reperfusion of the upper extremity. The study was prospectively registered in the German Clinical Trials Registry (DRKS00018931).

RESULTS

A total of 102 patients were included in the study and were randomized (51 per arm). The median age was 69.5 years, approximately two-thirds of the patients were male (69/102, 67.7%), and the mean body mass index was 25.6 kg/m2. Most patients were classified as American Society of Anesthesiologists II (55/102, 53.9%) or III (45/102, 44.1%). The primary endpoint, the transaminases on the first postoperative day (alanine aminotransferase /aspartate aminotransferase: remote ischemic preconditioning arm: 250 (35-1721)/320 (42-1525) U/L versus sham control arm: 283 (32-792)/356 (20-1851) U/L, P = .820/0.639), clinical outcomes as well as remote ischemic preconditioning biomarker levels were comparable between both arms.

CONCLUSION

Remote ischemic preconditioning did not achieve a significant reduction in postoperative transaminase levels, nor did it affect clinical results and biomarkers.

PREVENTION OF PATHOLOGICAL EFFECT OF ISCHEMIA-REPERFUSION IN LIVER RESECTION BY SEVOFLURANE PRECONDITIONING

BACKGROUND

The intermittent Pringle maneuver remains the major technique for controlling hemorrhage during liver surgery. Nevertheless, this procedure involves a risk of triggering a cascade of pathological changes resulting in the ischemia-reperfusion injury (I/R) effect. The pharmacological prevention of this I/R injury represents a promising approach. The aim of the study was to compare the effects of pharmacological preconditioning with sevoflurane and propofol-based intravenous anesthesia on the postoperative function of the liver as the primary end-point.

MATERIALS AND METHODS

A prospective cohort study includes the analysis of the data of 73 patients who underwent liver surgery. In the study group (n = 41), preconditioning with sevoflurane inhalation was provided 30 minutes prior to liver resection. In the control group (n = 32), sevoflurane preconditioning was not provided. The primary endpoints were blood lactate concentration shortly after the surgery and one day later; alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities on postoperative Days 1, 3, and 5 as markers of hepatocyte damage.

RESULTS

On postoperative Day 1, in patients of the study group, lactate decreased to preoperative levels, while in the control group, lactate content increased as compared to both preoperative levels and the levels immediately after liver resection. A significant difference in AST activity levels between the groups was registered on Day 5, although this difference was not clinically relevant. The decrease in the prothrombin index in the study group on Day 3 was superior to that in the control group. The multiple regression analysis demonstrated a moderate positive association between the number of resected liver segments and the markers of the functional state of the liver in the study group while in the control group, such association was not significant.

CONCLUSION

The protective effect of sevoflurane on the postoperative function of the liver is manifested by the lower level of blood lactate and the stable level of transaminase activity.

Early postoperative serum aspartate aminotransferase for prediction of post-hepatectomy liver failure

Background

Post-hepatectomy liver failure (PHLF) is a serious complication of hepatectomy. The current criteria for PHLF diagnosis (ISGLS consensus) require laboratory data on or after postoperative day (POD) 5, which may delay treatment for patients at risk. The present study aimed to determine the associations between early postoperative (POD1) serum aminotransferase levels and PHLF.

Methods

The medical records of patients who underwent hepatectomy at Ramathibodi Hospital from January 2008 to December 2019 were retrospectively examined. Patients were classified into PHLF and non-PHLF groups. Preoperative characteristics, intraoperative findings, and early postoperative laboratory data (serum AST, ALT, bilirubin, and international normalized ratio (INR) on POD0 to POD5) were analyzed.

Results

A total of 890 patients were included, of whom 31 (3.4%) had PHLF. Cut-off points for AST of 260 U/L and ALT of 270 U/L on POD1 were predictive of PHLF. In multivariate analysis, AST > 260 U/L on POD1, ICG-R15, major hepatectomy, blood loss, and INR were independently associated with PHLF.

Conclusions

Early warning from elevated serum AST on POD1, before a definitive diagnosis of PHLF is made on POD5, can help alert physicians that a patient is at risk, meaning that active management and vigilant monitoring can be initiated as soon as possible.

Does ALT Correlate with Survival After Liver Resection for Colorectal Liver Metastases?

Background

The pringle manoeuvre is commonly used during hepatectomy, which may cause ischaemia-reperfusion injury and transient liver dysfunction. Post-operative liver transaminases are often used to assess ischaemia-reperfusion injury, although there is conflicting evidence on survival outcomes. The primary aim was to assess post-operative alanine aminotransferase (ALT) with survival outcomes. Secondary aims were to assess ALT level with the length of stay and overall complications.

Methods

Post-operative day 2 ALT levels of five times the upper limit of normal (i.e. 280 U/L) were considered as clinically significant transaminitis. Kaplan-Meier survival curves were studied using log-rank analysis to identify the predictors of overall survival (OS) and recurrence-free survival (RFS).

Results

Out of 752 patients who underwent hepatectomy, 527 (70.1%) patients had low ALT (<280 U/L) and 225 (29.9%) patients had high ALT on day 2 post-op. Post-operative ALT did not affect OS (P = 0.883) or RFS (P = 0.063). Factors associated with a worse OS and RFS on multivariate analysis were pre-operative chemotherapy, number of tumours and largest tumour size (>4 cm). A high post-operative ALT was not associated with the increased length of stay or more complications.

Conclusions

Post-operative ALT does not affect survival outcomes post-hepatectomy for colorectal liver metastases.

Post-operative Day 1 Serum Transaminase Levels in Relation to Morbidity After Liver Resection

BACKGROUND

Post-operative serum transaminases have been proposed as possible early predictors of morbidity after liver resection. This study aimed to verify the clinical value of post-operative serum transaminases.

METHODS

Clinical data from 2001 to 2016 in a single non-academic referral HPB center were collected from a prospectively held database. Post-operative day 1 serum aspartate transaminase (AST) and alanine transaminase (ALT) were tested for their relationship with post-operative major morbidity, defined by a Clavien-Dindo score 3 or higher, and mortality.

RESULTS

For this analysis, 371 patients were included, including 149 (40%) undergoing major liver resections. In total, 17% of the patients developed major morbidity. Stepwise logistic regression demonstrated that AST, and not ALT, is an independent predictor for major morbidity (p = 0.017). The probability of major morbidity significantly increased with increasing AST values. A threshold value of 242 U/L was found to be predictive for one or more major complications.

CONCLUSIONS

In this study, post-operative serum AST on day 1 was a predictive factor for major morbidity after liver resection. For patients with low AST value, early discharge could be considered. However, because of the substantial inter-individual variability of AST values, more studies are needed to translate these results into clinical practice.

Predictors of complications after liver surgery: a systematic review of the literature

BACKGROUND

Numerous potential predictors of adverse outcomes have been reported but their performance and utilization in practice seem heterogenous. This study aimed to systematically review the literature on the role and value of predictors of complications after hepatectomy.

METHODS

A systematic review following the PRISMA guidelines was performed. Studies on liver transplant were excluded. Only studies assessing overall or major complications were included.

RESULTS

A total of 10'965 abstracts were screened. After application of exclusion criteria, 72 articles including 68'480 patients were included. A total of 72 markers with 48 pre-, 9 intra- and 15 postoperative factors were identified as predictors of complications. Preoperative and intraoperative predictive markers retrieved several times with the highest odds ratios (OR) were ASA score (OR range: 1.3-7.5, significant in 8 studies) and intraoperative need for red blood cell transfusion (OR range: 1.2-17.1, significant in 24 studies), respectively.

CONCLUSION

Numerous markers have been described to predict the complication risk after hepatectomy. Because of their intrinsic characteristics, most markers such as ASA score and need for red blood cell transfusion are of limited clinical interest. There is a clear need to identify new biomarkers and to develop scores that could easily be implemented in clinical practice.

Design, Analysis, and Pitfalls of Clinical Trials Using Ex Situ Liver Machine Perfusion: The International Liver Transplantation Society Consensus Guidelines

BACKGROUND

Recent trials in liver machine perfusion (MP) have revealed unique challenges beyond those seen in most clinical studies. Correct trial design and interpretation of data are essential to avoid drawing conclusions that may compromise patient safety and increase costs.

METHODS

The International Liver Transplantation Society, through the Special Interest Group "DCD, Preservation and Machine Perfusion," established a working group to write consensus statements and guidelines on how future clinical trials in liver perfusion should be designed, with particular focus on relevant clinical endpoints and how different techniques of liver perfusion should be compared. Protocols, abstracts, and full published papers of clinical trials using liver MP were reviewed. The use of a simplified Grading of Recommendations Assessment, Development, and Evaluation working group (GRADE) system was attempted to assess the level of evidence. The working group presented its conclusions at the International Liver Transplantation Society consensus conference "DCD, Liver Preservation, and Machine Perfusion" held in Venice, Italy, on January 31, 2020.

RESULTS

Twelve recommendations were proposed with the main conclusions that clinical trials investigating the effect of MP in liver transplantation should (1) make the protocol publicly available before the start of the trial, (2) be adequately powered, and (3) carefully consider timing of randomization in function of the primary outcome.

CONCLUSIONS

There are issues with using accepted primary outcomes of liver transplantation trials in the context of MP trials, and no ideal endpoint could be defined by the working group. The setup of an international registry was considered vital by the working group.

Effects of remote ischemic preconditioning on liver injury following hepatectomy: a systematic review and meta-analysis of randomized control trials

The protective effect of remote ischemic preconditioning (RIPC) against liver ischemia-reperfusion injury caused by hepatectomy remains controversial. We conducted this meta-analysis to evaluate the effectiveness and safety of RIPC strategies. PubMed, SinoMed, Embase, Cochrane Library, Medline, and Web of Science databases were searched for randomized controlled trials (RCT) that assessed the effectiveness and safety of RIPC strategies. The primary outcomes were operation time, index of liver function on postoperative day (POD) 1, postoperative complications, and postoperative hospital stay. The pooled odds ratios and weighted mean differences at 95% confidence interval (95% CI) were estimated using a fixed-effects or random-effects model. A total of 459 patients were included in seven RCTs. The alanine aminotransferase (ALT) and alanine aminotransferase (AST) values on POD1 were significantly different between the RIPC group and the N-RIPC group (P = 0.009 and P = 0.02, respectively). However, the heterogeneity was significant (I² = 84% and I² = 86%), and the results of a sensitivity analysis were unstable. There was no significant difference in the total bilirubin levels (P = 0.25) between the two groups on POD1. Subgroup analysis revealed no significant difference in the AST and ALT levels on POD1 between the RIIPC group and the N-RIPC group, regardless of whether the vascular control technique was used (all P > 0.05). Based on current evidence, RIPC does not alleviate liver injury caused by IRI after hepatectomy.

Laparoscopic Liver Resection Ameliorates the Postoperative Liver Function Impairment for Hepatocellular Carcinoma Patients

To study whether laparoscopic liver resection (LLR) is able to alleviate the postoperative liver function impairment for hepatocellular carcinoma patients, the clinical data of 103 patients were retrospectively analyzed, including 42 patients who underwent LLR and 61 patients who underwent open liver resection (OLR), during the period spanning from 2012 to 2017. The postoperative peak aspartate aminotransferase and alanine aminotransferase levels in the LLR group were significantly lower than those of the OLR group (209.76±189.516 vs. 262.55±181.19, P=0.046; 250.56±200.944 vs. 411.01±412.51, P=0.005, for aspartate aminotransferase and alanine aminotransferase, respectively). The recovering of postoperative total protein and albumin in the LLR group was faster than that in the OLR group, and the total protein and albumin levels on the postoperative day-5 were significantly higher in the LLR group than in the OLR group (62.528±9.427 vs. 57.87±6.101, P=0.019; 36.456±4.875 vs. 33.653±4.112, P=0.012, respectively). In conclusion, these data show that LLR alleviates postoperative liver function impairment and increases liver function recovery.

Effect of pharmacological preconditioning with sevoflurane during hepatectomy with intermittent portal triad clamping

BACKGROUND

During hepatectomy, intermittent portal triad clamping (IPC) reduces ischemia-reperfusion injuries. Pharmacological preconditioning with sevoflurane revealed similar properties. The aim of the study was to evaluate the combination of a sevoflurane preconditioning regimen with IPC on ischemia-reperfusion injuries.

METHODS

Three regimens of anesthesia were applied: group SEV with continuous application of sevoflurane, group PRO with continuous propofol infusion and group PC where continuous propofol was substituted by sevoflurane (adjusted to reach MAC∗1.5) for 15 min before IPC. Endpoints were the values of AST and ALT, factor V, prothrombin time, bilirubinemia over the 5-postoperative days (POD), morbidity and mortality at POD30 and POD90.

RESULTS

The ALT values at POD5 were lower in the PC group (n = 27) 74 (48 -98) IU/L compared to PRO (n = 26) and SEV (n = 67) respectively 110 (75 -152) and 100 (64 -168) IU/L (p = 0.038). The variation of factor V compared to preoperative values was less important in the PC and SEV groups respectively -14% and -16% vs -30% (PRO) (p = 0.047).

CONCLUSION

Our study suggests that sevoflurane attenuates ischemia-reperfusion injuries on liver function, compared to propofol, without benefit for a specific regimen of pharmacological preconditioning when IPC is applied.

Long-term survival after post-hepatectomy liver failure for colorectal liver metastases

BACKGROUND

While post-hepatectomy liver failure (PHLF) accurately predicts short-term mortality, its role in prognosticating long-term overall survival (OS) remains unclear.

METHODS

Patients who underwent hepatectomy for colorectal liver metastases (CRLM) after portal vein embolization during 1999-2015 were evaluated retrospectively. PHLF was defined per International Study Group of Liver Surgery (ISGLS) criteria and as _PeakBil >7 mg/dl. Survival was analyzed using log-rank statistic and Cox regression; patient mortality within 90 days was excluded.

RESULTS

Of 175 patients, 68 (39%) had PHLF according to ISGLS criteria, including 40 (23%) with ISGLS grade B/C, and 14 (8%) had _PeakBil >7 mg/dl. Patients with _PeakBil >7 mg/dl had significantly worse OS than patients without PHLF (median OS, 16 vs 58 months, p = 0.001). Patients with ISGLS defined PHLF (p = 0.251) and patients with ISGLS grade B/C PHLF (p = 0.220) did not have worse OS than patients without PHLF.

CONCLUSION

Peak bilirubin >7 mg/dl impacts on long-term survival after hepatectomy for CRLM and is a better predictor of long-term survival than ISGLS-defined PHLF.

Serum procalcitonin concentration within 2 days postoperatively accurately predicts outcome after liver resection

Background:

Relatively high mortality and morbidity rates are reported after liver resection (LR). However, the early predictors of complications after LR are not clear. This study was performed to clarify the usefulness of procalcitonin (PCT) for the early prediction of complications after elective LR.

Methods:

This observational study included 72 consecutive patients who underwent elective LR from December 2015 to March 2017. Patients were categorized into two groups: those with and without postoperative complications (Clavien-Dindo grade ≥II). The values of postoperative inflammatory markers (white blood cell [WBC] count, C-reactive protein [CRP] and PCT) were compared between the two groups.

Results:

CRP and PCT were significantly higher in patients with than without complications; however, the WBC count showed no difference within 5 days postoperatively. The maximum area under the receiver operating characteristic curves within 2 days after LR using the WBC count, CRP and PCT were 0.608, 0.697 and 0.860, respectively, PCT had the best predictive ability in the early postoperative period. The PCT level peaked within 2 days postoperatively in 61 patients (85%). The maximum PCT level within 2 days postoperatively (PCT1−2) was significantly higher in patients with than without complications (0.52 vs. 0.19 ng/mL, p<0.001). A cutoff PCT1−2 level of 0.35 ng/mL achieved 80% sensitivity and 83% specificity. In patients without complications, there was no difference in PCT1−2 even when the surgical procedure differed (p=0.935).

Conclusions:

PCT1−2 is an early predictive marker after LR and can be similarly used regardless of the LR procedure.

Post-operative delayed elevation of ALT correlates with early death in patients with HBV-related hepatocellular carcinoma and Post-hepatectomy Liver Failure

BACKGROUND

Post-hepatectomy Liver Failure (PHLF) remains the primary cause of perioperative death. The kinetics of transaminase levels are usually measured as markers of hepatocellular injury following partial hepatectomy, but their correlation with PHLF and post-operative mortality is unclear. The aim of study was to compare the post-operative transaminase kinetics with short term survival in those patients that developed PHLF.

METHODS

A retrospective review of patients with HBV-related HCC and who developed PHLF was performed. Logistic regression analysis was conducted to analyze risk factors for postoperative delayed elevation of ALT (PDE-ALT) PHLF and lethal PHLF.

RESULT

Of the 69 patients who developed PHLF 36 (52%) died. In those patients who died the mean ± SD ALT and AST rose from day (POD) 1-3 and continued to fluctuate with highly abnormal levels beyond day 3 with a mean ± SD peak ALT level beyond POD 3 of 1851 ± 1644 U/L (p < 0.001).

CONCLUSIONS

The kinetics of the post-operative transaminases were significantly correlated with perioperative mortality in those patients who developed PHLF. PDE-ALT indicates an increased risk of death in HBV-related HCC patients with PHLF.

Use of aspirin and bleeding-related complications after hepatic resection

Background

The operative risk of hepatectomy under antiplatelet therapy is unknown. This study sought to assess the outcomes of elective hepatectomy performed with or without aspirin continuation in a well balanced matched cohort.

Methods

Data were retrieved from a multicentre prospective observational study. Aspirin and control groups were compared by non-standardized methods and by propensity score (PS) matching analysis. The main outcome was severe (Dindo–Clavien grade IIIa or more) haemorrhage. Other outcomes analysed were intraoperative transfusion, overall haemorrhage, major morbidity, comprehensive complication index (CCI) score, thromboembolic complications, ischaemic complications and mortality.

Results

Before matching, there were 118 patients in the aspirin group and 1685 in the control group. ASA fitness grade, cardiovascular disease, previous history of angina pectoris, angioplasty, diabetes, use of vitamin K antagonists, cirrhosis and type of hepatectomy were significantly different between the groups. After PS matching, 108 patients were included in each group. There were no statistically significant differences between the aspirin and control groups in severe haemorrhage (6·5 versus 5·6 per cent respectively; odds ratio (OR) 1·18, 95 per cent c.i. 0·38 to 3·62), intraoperative transfusion (23·4 versus 23·7 per cent; OR 0·98, 0·51 to 1·87), overall haemorrhage (10·2 versus 12·0 per cent; OR 0·83, 0·35 to 1·94), CCI score (24 versus 28; P = 0·520), major complications (23·1 versus 13·9 per cent; OR 1·82, 0·92 to 3·79) and 90-day mortality (5·6 versus 4·6 per cent; OR 1·21, 0·36 to 4·09).

Conclusion

This observational study suggested that aspirin continuation is not associated with a higher rate of bleeding-related complications after elective hepatic surgery.

Risk factors for pulmonary complications after hepatic resection: role of intraoperative hemodynamic instability and hepatic ischemia

BACKGROUND

Postoperative operative pulmonary complications (PPCs) after hepatic surgery are associated with increased length of hospital stays. Intraoperative blood transfusion, extensive resection and different comorbidities have been identified. Other parameters, like time of hepatic ischemia, have neither been clinically studied, though experimental studies show that hepatic ischemia can provide lung injury. The objective of this study was to determinate the risk factors of postoperative pulmonary complications (PPCs) after hepatic resection within 7 postoperative days.

METHOD

Ninety-four patients consecutively who underwent elective hepatectomy between January and December 2013. Demographic data, pathological variables, and preoperative, intraoperative, and postoperative variables had been prospectively collected in a data base. The dependant variables studied were the occurrence of PPCs, defined before analysis of the data.

RESULTS

PPCs occurred in 32 (34%) patients. A multivariate analysis allowed identifying the risk factors for PPCs. On multivariate analysis, preoperative gamma-glutamyltransferase (GGT) elevation OR =5,12 [1,85-15,69] p = 0,002, liver ischemia duration OR = 1,03 [1,01-1,06] p = 0,01 and the intraoperative use of vasopressor OR = 4,40 [1,58-13,36] p = 0,006 were independently associated with PPCs. For every 10 min added in ischemia duration, the OR of the risk of PPCs was estimated to be 1.37 (CI95% = [1.08-1.81], p = 0.01).

CONCLUSION

Three risk factors for PPCs have been identified in a population undergoing liver resection: preoperative GGT elevation, ischemia duration and the intraoperative use of vasopressor. PPCs after liver surgery could be related to lung injury induced by liver ischemia reperfusion and not solely by direct infectious process. That could explain why factors influencing directly or indirectly liver ischemia were independently associated with PPCs.

Effect of Remote Ischaemic Preconditioning on Liver Injury in Patients Undergoing Major Hepatectomy for Colorectal Liver Metastasis: A Pilot Randomised Controlled Feasibility Trial

Background

Liver resection produces excellent long-term survival for patients with colorectal liver metastases but is associated with significant morbidity and mortality from ischaemia reperfusion injury (IRI). Remote ischaemic preconditioning (RIPC) can reduce the effect of IRI. This pilot randomised controlled trial evaluated RIPC in patients undergoing major hepatectomy at the Royal Free Hospital, London.

Methods

Sixteen patients were randomised to RIPC or sham control. RIPC was induced through three 10-min cycles of alternate ischaemia and reperfusion to the leg. At baseline and immediately post-resection, transaminases and indocyanine green (ICG) clearance were measured.

Findings

The RIPC group had lower ALT and AST levels immediately post-resection (ALT: 43% lower 497 ± 165 vs 889 ± 170 IU/L; p = 0.019 AST: 54% lower 408 ± 166 vs 836 ± 167 IU/L; p = 0.001) and at 24 h (ALT: 41% lower 412 ± 144 vs 698 ± 137 IU/L; p = 0.026 AST: 50% lower 316 ± 116 vs 668 ± 115 IU/L; p = 0.02). ICG clearance was reduced in controls versus RIPC immediately after resection (ICG-PDR: 11.1 ± 1.1 vs 16.5 ± 1.4%/min; p = 0.035).

Conclusions

This pilot study shows that RIPC has potential to reduce liver injury following hepatectomy justifying a prospective RCT powered to demonstrate clinical benefits.

Postoperative day one serum alanine aminotransferase does not predict patient morbidity and mortality after elective liver resection in non-cirrhotic patients

Serum aminotransferases have been used as surrogate markers for liver ischemia-reperfusion injury that follows liver surgery. Some studies have suggested that rises in serum alanine aminotransferase (ALT) correlate with patient outcome after liver resection. We assessed whether postoperative day 1 (POD 1) ALT could be used to predict patient morbidity and mortality following liver resection. We reviewed our prospectively held database and included consecutive adult patients undergoing elective liver resection in our institution between January 2013 and December 2014. Primary outcome assessed was correlation of POD 1 ALT with patient's morbidity and mortality. We also assessed whether concurrent radiofrequency ablation, neoadjuvant chemotherapy and use of the Pringle maneuver significantly affected the level of POD 1 ALT. A total of 110 liver resections were included in the study. The overall in-hospital patient morbidity and mortality were 31.8% and 0.9%, respectively. The median level of POD 1 ALT was 275 IU/L. No correlation was found between POD 1 serum ALT levels and patient morbidity after elective liver resection, whilst correlation with mortality was not possible because of the low number of mortalities. Patients undergoing concurrent radiofrequency ablation were noted to have an increased level of POD 1 serum ALT but not those given neoadjuvant chemotherapy and those in whom the Pringle maneuver was used. Our study demonstrates POD 1 serum ALT does not correlate with patient morbidity after elective liver resection.

Postoperative peak transaminases correlate with morbidity and mortality after liver resection

BACKGROUND

Transaminase levels are usually measured as markers of hepatocellular injury following liver resection, but recent evidence was unclear on their clinical value. This study aimed to identify factors that determine peak postoperative transaminase levels and correlated transaminase levels to postoperative complications.

STUDY DESIGN

All liver resections performed at a single center between 2006 and 2015 were included in the analysis. Multivariate analysis was used to identify factors that determine peak ALT and AST levels and postoperative morbidity and mortality. An ALT and AST cutoff for the prediction of mortality was determined using receiver operating characteristic curves analysis.

RESULTS

A total of 539 resections were included. Clavien-Dindo grade III or higher complications, intraoperative transfusion, and operative duration were identified as determinants of peak transaminases. A peak AST cut-off value for predicting mortality was defined at 828 U/L, with an area under the curve of 0.81 (0.73-0.89). The cut-off was an independent predictor of mortality (P < 0.01) along with (intraoperative) transfusion (P < 0.01), fifty-fifty criteria (P < 0.01), and age (P < 0.01).

CONCLUSION

Postoperative transaminase levels are independent predictors of postoperative morbidity and mortality and therefore clinically relevant. Transaminase levels usually peak during the first 24 h after surgery and thus possess early prognostic power in terms of postoperative mortality.

Warm ischemia time-dependent variation in liver damage, inflammation, and function in hepatic ischemia/reperfusion injury

BACKGROUND

Hepatic ischemia/reperfusion (I/R) injury is characterized by hepatocellular damage, sterile inflammation, and compromised postoperative liver function. Generally used mouse I/R models are too severe and poorly reflect the clinical injury profile. The aim was to establish a mouse I/R model with better translatability using hepatocellular injury, liver function, and innate immune parameters as endpoints.

METHODS

Mice (C57Bl/6J) were subjected to sham surgery, 30min, or 60min of partial hepatic ischemia. Liver function was measured after 24h using intravital microscopy and spectroscopy. Innate immune activity was assessed at 6 and 24h of reperfusion using mRNA and cytokine arrays. Liver inflammation and function were profiled in two patient cohorts subjected to I/R during liver resection to validate the preclinical results.

RESULTS

In mice, plasma ALT levels and the degree of hepatic necrosis were strongly correlated. Liver function was bound by a narrow damage threshold and was severely impaired following 60min of ischemia. Severe ischemia (60min) evoked a neutrophil-dominant immune response, whereas mild ischemia (30min) triggered a monocyte-driven response. Clinical liver I/R did not compromise liver function and displayed a cytokine profile similar to the mild I/R injury model.

CONCLUSIONS

Mouse models using ≤30min of ischemia best reflect the clinical liver I/R injury profile in terms of liver function dynamics and type of immune response.

GENERAL SIGNIFICANCE

This short duration of ischemia therefore has most translational value and should be used to increase the prospects of developing effective interventions for hepatic I/R.

Mitochondrial bioenergetics and posthepatectomy liver dysfunction

BACKGROUND

Liver regeneration requires an enormous energy supply. Experimental evidence suggests that mitochondrial function is of paramount importance for liver regeneration. However, this has not been investigated in the clinical setting. We aimed to: (i) evaluate changes in mitochondrial function during hepatectomy, especially after hepatic pedicle clamping; and (ii) correlate these changes with postoperative hepatocellular function and clinical outcome.

MATERIALS AND METHODS

Prospective study of thirty patients undergoing hepatectomy. Measurement of mitochondrial membrane potential, respiration and adenosine triphosphate content in intra-operative liver biopsies performed in nonresected parenchyma. Correlation of findings with duration of hepatic pedicle clamping, postoperative markers of hepatocellular necrosis and function (aminotransferases, arterial lactate, international normalized ratio, bilirubin), and morbidity.

RESULTS

Longer hepatic pedicle clamping was associated with worse mitochondrial depolarization (r = -0·519; P = 0·011) and longer lag phase (r = 0·568; P = 0·006). Higher postoperative peak aminotransferases, international normalized ratio and bilirubin correlated with worse mitochondrial function (P < 0·05). After major hepatectomy, mitochondrial respiration correlated with postoperative arterial lactate clearance (r = 0·756; P = 0·049). Mitochondrial bioenergetic parameters were significantly decreased in patients with liver-specific morbidity and postoperative liver failure (P < 0·05). On multivariate analysis, decrease in mitochondrial potential was an independent risk factor for liver-specific morbidity (OR = 13·7; P = 0·043). Worse lag phase was highly predictive of posthepatectomy liver failure (area under the curve: 0·933; P = 0·008).

CONCLUSIONS

There is a relationship between mitochondrial function, duration of hepatic pedicle clamping and clinical outcome after hepatectomy. Mitochondrial bioenergetics can potentially translate into clinical practice, assisting in earlier diagnosis of postoperative liver dysfunction, and as a target for future pharmacological therapies.

Arterial Lactate Concentration at the End of an Elective Hepatectomy Is an Early Predictor of the Postoperative Course and a Potential Surrogate of Intraoperative Events

OBJECTIVES

To test the prognostic impact of arterial lactate concentration at the end-of-surgery (LCT-EOS) on postoperative outcome after elective liver-resections and to identify the predictors of an increase in LCT-EOS.

BACKGROUND DATA

A recent systematic-review of risk-prediction-models for liver resections has evidenced their poor accuracy and a deficit in the evaluation of intraoperative events. LCT-EOS is a marker of impaired tissue oxygenation.

METHODS

This prospectively-designed study was based on a training-cohort of 519 patients and a validation-cohort of 466 patients. For each of the endpoints (high comprehensive complication index (CCI) scores, 90-day-mortality and severe-morbidity), prognostic-models were built by logistic-regression using the training-cohort. These models were thereafter tested in the validation-cohort and their performance (discrimination, accuracy, calibration) assessed. Independent predictors of LCT-EOS were also identified.

RESULTS

In the training-cohort, LCT-EOS cutoff best discriminating high-CCI, 90-day-mortality and severe-morbidity were 3, 3 and 2.8 mmol/L (and the corresponding AUROC 0.86, 0.87 and 0.76). LCT-EOS was an independent predictor of endpoints and adding LCT-EOS to the other predictors increased by 16.4%, 34.5% and 17.7% the accuracy of the models for high-CCI, 90-day-mortality and severe-morbidity, respectively. The models had high calibration and accuracy. Diabetes, repeat-hepatectomy, major-hepatectomy, synchronous-major-procedure, inflow-occlusion and blood-transfusion were independent predictors of LCT-EOS >3 mmol/L.

CONCLUSIONS

LCT-EOS >3 mmol/L is an early predictor of postoperative-outcome and should be used as a tool to determine patients requiring critical-care and as an endpoint in studies measuring the impact of perioperative interventions.

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.

Improving the quality of liver resection: a systematic review and critical analysis of the available prognostic models

BACKGROUND

Liver resection is considered to offer the only hope of cure for patients with liver malignancy. However, there are concerns about its safety, particularly in view of the increasing efficacy of less invasive strategies. No systematic review of prognostic research in liver resections has yet been performed.

METHODS

A systematic search identified articles published between 1999 and 2012 that performed a risk prediction analysis in patients undergoing liver resection. Studies were included if an outcome occurring within 90 days of surgery was identified, multivariable analysis performed and regression coefficients provided. The main endpoints were the outcomes and predictors chosen by the investigators, their definition, the performance and validity of the models, and the quality of the study as assessed using the QUIPS (quality in prognosis studies) tool.

RESULTS

A total of 91 studies were included. Eleven were prospective, but only two of these were registered. Twenty-eight endpoints were identified. These focused on postoperative morbidity or mortality, but many were redundant or ill defined and other relevant patient-reported outcomes were lacking. Predictors were not standardized, were poorly defined and overlapped. Only nine studies assessed the performance of their models and seven made an internal or temporal validation, but none reported an external validation or impact analysis. The median QUIPS score was 34 out of 50, indicating a high risk for bias.

CONCLUSION

Prognostic research in liver resection is still at the developmental stage.

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS): impact of the inter-stages course on morbi-mortality and implications for management

BACKGROUND

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) was recently developed to induce rapid hypertrophy and reduce post-hepatectomy liver failure in patients with insufficient remnant liver volume (RLV). However, mortality rates >12% have been reported. This study aimed to analyze the perioperative course of ALPPS and to identify factors associated with morbi-mortality.

METHODS

Between April 2011 and September 2013, 62 patients operated in 9 Franco-Belgian hepatobiliary centres underwent ALPPS for colorectal metastases (N = 50) or primary tumors, following chemotherapy (N = 50) and/or portal vein embolization (PVE; N = 9).

RESULTS

Most patients had right (N = 31) or right extended hepatectomy (N = 25) (median RLV/body weight ratio of 0.54% [0.21-0.77%]). RLV increased by 48.6% [-15.3 to 192%] 7.8 ± 4.5 days after stage1, but the hypertrophy decelerated beyond 7 days. Stage2 was cancelled in 3 patients (4.8%) for insufficient hypertrophy, portal vein thrombosis or death and delayed to ≥9 days in 32 (54.2%). Overall, 25 patients (40.3%) had major complication(s) and 8 (12.9%) died. Fourteen patients (22.6%) had post-stage1 complication of whom 5 (35.7%) died after stage2. Factors associated with major morbi-mortality were obesity, post-stage1 biliary fistula or ascites, and infected and/or bilious peritoneal fluid at stage2. The latter was the only predictor of Clavien ≥3 by multivariate analysis (OR: 4.9; 95% CI: 1.227-19.97; p = 0.025). PVE did not impact the morbi-mortality rates but prevented major cytolysis that was associated with poor outcome.

CONCLUSIONS

The inter-stages course was crucial in determining ALPPS outcome. The factors of high morbi-mortality rates associated with ALPPS are linked to the technique complexity.