Early Morbidity and Mortality after Minimally Invasive Liver Resection for Hepatocellular Carcinoma: a Propensity-Score Matched Comparison with Open Resection

Association of the Number of Concurrent Metabolic Syndrome Risk Factors with Textbook Outcomes Following Liver Resection for Patients with Hepatocellular Carcinoma: A Multicenter Study

BACKGROUND

There is little information regarding the impact of the number of concurrent metabolic syndrome (MetS) risk factors on the textbook outcomes (TO) in patients with hepatocellular carcinoma (HCC) following liver resection.

PATIENTS AND METHODS

Data from patients who underwent liver resection between 2015 and 2023 in a multicenter database were retrospectively reviewed (N = 3156). According to the guidelines, MetS risk factors include obesity, hypertension, diabetes, and dyslipidemia.

RESULTS

In this study, 2056 (65.1%) patients achieved TO. The incidence of TO was 63.1% in patients with ≥ 1 MetS risk factor, which was lower than that in patients without any MetS risk factors (67.5%, P = 0.011). As the number of MetS risk factors increased, the probability of not achieving TO gradually increased. The non-TO rates in patients with no, 1, 2, and ≥ 3 MetS risk factors were 32.5%, 35.9%, 37.6% and 40.2%, respectively (Ptrend = 0.005). Multivariate logistic regression confirmed that the number of MetS risk factors (0 as a reference; 1, OR 1.220, 95% CI 1.029-1.447, P = 0.022; 2, OR 1.397, 95% CI 1.113-1.755, P = 0.004; ≥ 3, OR 1.647, 95% CI 1.197-2.264, P = 0.002) independently contributed to non-TO in patients with HCC after liver resection. Both the 5-year recurrence-free survival (TO: 50.7% versus non-TO: 43.9%, P < 0.001) and overall survival rates (TO: 71.0% versus non-TO: 58.7%, P < 0.001) of TO patients were significantly better than those of non-TO patients.

CONCLUSIONS

Concurrent MetS risk factors can adversely impact TO achievement in patients with HCC after liver resection. The more risk factors patients have, the less likely they are to achieve TO.

Development of an Optimized Promoter System for Exosomal and Naked AAV Vector-Based Suicide Gene Therapy in Hepatocellular Carcinoma

Suicide gene therapy is a promising strategy for the potential treatment of hepatocellular carcinoma (HCC). However, the lack of high transduction efficiency and targeted vectors in delivering the suicide genes to only the HCC cells is a major impediment. In the present study, we utilized an adeno-associated virus serotype 6 (AAV6) and its exosomal counterpart (exo-AAV) comprising of an inducible Caspase 9 (iCasp9) gene under the control of different promoter systems for targeting HCC cells. We employed a ubiquitous cytomegalovirus immediate early enhancer/chicken β actin promoter (CAG), a liver-specific promoter (LP1), and a baculoviral IAP repeat-containing protein 5 (BIRC5) promoter for liver and cancer cell-specific expression of iCasp9, respectively. We further evaluated these vectors in Huh7 cells for their ability to kill the target cells. BIRC5 and LP1 promoter-driven iCasp9 vectors demonstrated superior cytotoxicity when compared to CAG promoter-driven iCasp9 vectors. Further validation in a murine model of HCC demonstrated that the LP1-iCasp9 or Birc5-iCasp9-based AAV6 vectors contributed to tumor regression (∼2 fold) as effectively as the AAV6-CAG-iCasp9 vectors (∼1.9 fold). Similarly, exo-AAV6 vectors showed ∼2.1 to 2.8 fold superior in vivo tumor regression when compared to mock-treated animals. Our study has developed two novel promoters (LP1 or BIRC5) whose efficacy is comparable to a strong ubiquitous promoter in both AAV and exo-AAV systems. This expands the toolkit of AAV vectors for safe and effective treatment of HCC.

Hepatocellular Carcinoma: Surveillance, Diagnosis, Evaluation and Management

Hepatocellular carcinoma (HCC) ranks fourth in cancer-related deaths worldwide. Semiannual surveillance of the disease for patients with cirrhosis or hepatitis B virus allows for early detection with more favorable outcomes. The current underuse of surveillance programs demonstrates the need for intervention at both the patient and provider level. Mail outreach along with navigation provision has proven to increase surveillance follow-up in patients, while provider-targeted electronic medical record reminders and compliance reports have increased provider awareness of HCC surveillance. Imaging is the primary mode of diagnosis in HCC with The Liver Imaging Reporting and Data System (LI-RADS) being a widely accepted comprehensive system that standardizes the reporting and data collection for HCC. The management of HCC is complex and requires multidisciplinary team evaluation of each patient based on their preference, the state of the disease, and the available medical and surgical interventions. Staging systems are useful in determining the appropriate intervention for HCC. Early-stage HCC is best managed by curative treatment modalities, such as liver resection, transplant, or ablation. For intermediate stages of the disease, transarterial local regional therapies can be applied. Advanced stages of the disease are treated with systemic therapies, for which there have been recent advances with new drug combinations. Previously sorafenib was the mainstay systemic treatment, but the recent introduction of atezolizumab plus bevacizumab proves to have a greater impact on overall survival. Although there is a current lack of improved outcomes in Phase III trials, neoadjuvant therapies are a potential avenue for HCC management in the future.

Synergistic Strategies for Gastrointestinal Cancer Care: Unveiling the Benefits of Immunonutrition and Microbiota Modulation

Gastrointestinal (GI) cancers are a group of highly prevalent malignant tumors affecting the gastrointestinal tract. Globally, one in four cancer cases and one in three cancer deaths are estimated to be GI cancers. They can alter digestive and absorption functions, leading to severe malnutrition which may worsen the prognosis of the patients. Therefore, nutritional intervention and monitoring play a fundamental role in managing metabolic alterations and cancer symptoms, as well as minimizing side effects and increasing the effectiveness of chemotherapy. In this scenario, the use of immunonutrients that are able to modulate the immune system and the modification/regulation of the gut microbiota composition have gained attention as a possible strategy to improve the conditions of these patients. The complex interaction between nutrients and microbiota might contribute to maintaining the homeostasis of each individual's immune system; therefore, concurrent use of specific nutrients in combination with traditional cancer treatments may synergistically improve the overall care of GI cancer patients. This work aims to review and discuss the role of immunonutrition and microbiota modulation in improving nutritional status, postoperative recovery, and response to therapies in patients with GI cancer.

Nomogram predicting surgical risk of laparoscopic left-sided hepatectomy for hepatolithiasis

OBJECTIVE

To explore the surgical risk factors of laparoscopic left-sided hepatectomy for hepatolithiasis and establish and validate a nomogram to estimate the corresponding surgical risks.

METHODS

Patients with hepatolithiasis who underwent laparoscopic left-sided hepatectomy were retrospectively enrolled. Demographic data, clinicopathological parameters, and surgical factors were collected. Three hundred fifty-three patients were enrolled and randomly divided into training set (n=267) and validation set (n=86) by 3:1. Conversion to laparotomy was used as a surrogate index to evaluate the surgical risk. Univariate analysis was used to screen potential surgical risk factors, and multivariate analysis using logistic regression model was used to screen independent surgical risk factors. Nomogram predicting the surgical risks was established based on the independent risk factors. Discrimination, calibration, decision curve, and clinical impact analyses were used to evaluate the performance of the nomogram on the statistical and clinical aspects both in the training and validation sets.

RESULTS

Five independent surgical risk factors were identified in the training set, including recurrent abdominal pain, bile duct stricture, ASA classification ≥2, extent of liver resection, and biliary tract T tube drainage. No collinearity was found among these five factors, and a nomogram was established. Performance analyses of the nomogram showed good discrimination (AUC=0.850 and 0.817) and calibration (Hosmer-Lemeshow test, p=0.530 and 0.930) capabilities both in the training and validation sets. Decision curve and clinical impact analyses also showed that the prediction performance was clinically valuable.

CONCLUSIONS

A nomogram was established and validated to be effective in evaluating and predicting the surgical risk of patients undergoing laparoscopic left-sided hepatectomies for hepatolithiasis.

The Outcome of Conversion to Hand-Assisted Laparoscopic Surgery in Laparoscopic Liver Resection

BACKGROUND

Hand-assisted laparoscopic surgery (HALS) is known as a useful option. However, the outcome and predictor of conversion to HALS in laparoscopic liver resection (LLR) are unclear.

METHODS

Data from consecutive patients who planned pure LLR between 2011 and 2020 were retrospectively reviewed. Univariate and multivariate analyses were performed and compared pure LLR, HALS, and converted open liver resection (OLR).

RESULTS

Among the 169 LLRs, conversion to HALS was performed in 19 (11.2%) and conversion to OLR in 16 (9.5%). The most frequent reasons for conversion to HALS were failure to progress (11 cases). Subsequently, bleeding (3 cases), severe adhesion (2 cases), and oncological factors (2 cases) were the reasons. In the multivariable analysis, the tumor located in segments 7 or 8 (p = 0.002) was evaluated as a predictor of conversion to HALS. Pure LLR and HALS were associated with less blood loss than conversion to OLR (p = 0.005 and p = 0.014, respectively). However, there was no significant difference in operation time, hospital stay, or severe complications.

CONCLUSIONS

The predictor of conversion to HALS was a tumor located in segments 7 or 8. The outcome of conversion to HALS was not inferior to pure LLR in terms of bleeding, operation time, hospital stay, or severe complication.

Predictors of recurrence following laparoscopic minor hepatectomy for hepatocellular carcinoma in the UK

AIMS

Minor hepatectomy, which is increasingly carried out laparoscopically (LLR), is a cornerstone of curative treatment for hepatocellular carcinoma (HCC). The majority of relevant publications however originate from regions with endemic viral hepatitis. Although the incidence of HCC in the UK is increasing, little is known about outcomes following LLR.

METHODS

Consecutive patients undergoing minor (involving ≤2 segments) LLR or open resection (OLR) at our institute between 2014 and 2021 were compared. Selection from a plethora of factors potentially impacting on overall (OS) and disease free survival (DFS) was optimised with Lasso regression. To enable analysis of patients having repeat resection, multivariate frailty modelling was utilised to calculate hazard ratios (HR).

RESULTS

The analysis of 111 liver resections included 55 LLR and 56 OLR. LLR was associated with a shorter hospital stay (5 ± 2 vs. 7 ± 2 days; p < 0.001) and a lower comprehensive complication index (4.43 vs. 9.96; p = 0.006). Mean OS (52.3 ± 2.3 vs. 49.9 ± 3.0 months) and DFS (33.9 ± 3.4 vs. 36.5 ± 3.6 months; p = 0.59) were comparable between LLR and OLR, respectively (median not reached). Presence of mixed cholangiocarcinoma/HCC, satellite lesions and AFP level predicted OS and DFS. In addition tumour size was predictive of DFS.

CONCLUSIONS

In the studied population minor LLR was associated with shorter hospital stay and fewer complications while offering non-inferior long-term outcomes. A number of predictors for disease free survival have been elucidated that may aid in identifying patients with a high risk of disease recurrence and need for further treatment.

Venous thromboembolism (VTE) after open hepatectomy compared to minimally invasive liver resection: a systematic review and meta-analysis

BACKGROUND

Even though the risk of postoperative venous thromboembolism (VTE) after liver resection is well recognized, the association between surgical approach and VTE risk is unknown. This study aims to compare VTE rates following open liver resection (OLR) and minimally invasive liver resection (MILR).

METHODS

MEDLINE, Web Of Sciences and EMBASE databases were interrogated to identify eligible studies published between February 2016 and August 2022. Studies were considered suitable if they reported a comparison between OLR and MILR (including laparoscopic liver resection [LLR] or robotic liver resection [RLR]).

RESULTS

Fourteen studies including 11 356 patients met the inclusion criteria. 5622 patients underwent OLR and 5734 patients underwent MILR. The VTE rate was higher among patients who underwent OLR compared to MILR (2.8% vs 1.4%, OR (95% CI) = 1.84, p=<00001). Similarly, the subgroup analysis showed a higher rate of deep venous thrombosis (DVT) (1.4% vs 0.7%, OR (95% CI) = 1.98, p = 0.02) and pulmonary embolism (PE) (1.3% vs 0.7%, OR (95% CI) = 1.88, p = 0.002) in patients who underwent OLR compared to MILR.

DISCUSSION

Patients who undergo open hepatectomy have a higher incidence of postoperative VTE when compared to those undergoing minimally invasive liver resection. This finding was consistent for both DVT and PE.

Minimally invasive versus open liver resection for hepatocellular carcinoma: a propensity score matching analysis of 224 patients

PURPOSE

To compare the peri-operative and long-term survival outcomes of minimally invasive liver resection (MILR) (robotic or laparoscopic) with open liver resection (OLR) in patients with hepatocellular carcinoma (HCC).

METHODS

Data of patients who underwent liver resection for HCC were reviewed from a prospectively collected database. Outcomes of MILR were compared with those of OLR. A propensity score matching analysis with a ratio of 1:1 was performed to minimise the potential bias in clinical pathological factors.

RESULTS

From January 2003 to December 2017, a total of 705 patients underwent liver resection for HCC. Amongst them, 112 patients received MILR and 593 patients received OLR. After propensity score matching, there were 112 patients in each of the MILR and OLR groups. Patients were matched by age, sex, hepatitis status, presence of cirrhosis, platelet count, albumin level, bilirubin level, alkaline phosphatase (ALP) level, alanine transferase (ALT) level, creatinine level, tumour differentiation, tumour size, tumour number, presence of tumour rupture, presence of vascular invasion, extent of liver resection (minor/major) and difficulty score. The 1-, 3- and 5-year overall survival rates were 94.4%, 90.4% and 82.3% in the MILR group vs 95.4%, 80.5% and 71.8% in the open group (p = 0.240). The 1-, 3- and 5-year disease-free survival rates were 81.0%, 63.1% and 55.8% in the MILR group vs 79.1%, 58.1% and 45.7 in the open group (p = 0.449). The MILR group demonstrated significantly less blood loss (p < 0.001), less blood transfusion (p = 0.004), lower post-operative complications (p < 0.001) and shorter hospital stay (p < 0.001) when compared with the OLR group.

CONCLUSIONS

Our data shows MILR yielded superior post-operative outcomes to OLR, with comparable survival outcomes.

Management of Hepatocellular Carcinoma: A Review

Importance

Hepatocellular carcinoma (HCC) is the sixth most common malignancy and fourth leading cause of cancer-related death worldwide. Recent advances in systemic and locoregional therapies have led to changes in many guidelines regarding systemic therapy, as well as the possibility to downstage patients to undergo resection. This review examines the advances in surgical and medical therapies relative to multidisciplinary treatment strategies for HCC.

Observations

HCC is a major health problem worldwide. The obesity epidemic has made nonalcoholic fatty liver disease a major risk factor for the development of HCC. Multiple societies, such as the American Association for the Study of Liver Diseases, the European Association for the Study of the Liver, the Asian Pacific Association for the Study of the Liver, and the National Comprehensive Cancer Network, provide guidelines for screening at-risk patients, as well as define staging systems to guide optimal treatment strategies. The Barcelona Clinic Liver Cancer staging system is widely accepted and has recently undergone updates with the introduction of new systemic therapies and stage migration.

Conclusions and Relevance

The treatment of patients with HCC should involve a multidisciplinary approach with collaboration among surgeons, medical oncologists, radiation oncologists, and interventional radiologists to provide optimal care. Treatment paradigms must consider both tumor and patient-related factors such as extent of liver disease, which is a main driver of morbidity and mortality. The advent of more effective systemic and locoregional therapies has prolonged survival among patients with advanced disease and allowed some patients to undergo surgical intervention who would otherwise have disease considered unresectable.

Safety of intermittent Pringle maneuver during minimally invasive liver resection in patients with hepatocellular carcinoma with and without cirrhosis

Purpose

The aim of this study was to analyze the impact of minimally invasive intermittent Pringle maneuver (IPM) on postoperative outcomes in patients with hepatocellular carcinoma (HCC) and liver cirrhosis.

Methods

In this retrospective cohort study, we evaluated the safety of IPM in patients with HCC who underwent minimally invasive liver resection during five years at our center. Factors influencing the use of IPM were examined in univariate and multivariate regression analysis. Cases with use of IPM (IPM) and those without use of IPM (no IPM) were then compared regarding intraoperative and postoperative outcomes after propensity score matching (PSM) for surgical difficulty.

Results

One hundred fifty-one patients underwent liver resection for HCC at our center and met inclusion criteria. Of these, 73 patients (48%) received IPM with a median duration of 18 min (5–78). One hundred patients (66%) had confirmed liver cirrhosis. In multivariate analysis, patients with large tumors (≥ 3 cm) and difficult tumor locations (segments VII or VIII) were more likely to undergo IPM (OR 1.176, p = 0.043, and OR 3.243, p = 0.001, respectively). After PSM, there were no differences in intraoperative blood transfusion or postoperative complication rates between the IPM and no IPM groups. Neither did we observe any differences in the subgroup analysis for cirrhotic patients. Postoperative serum liver function tests were not affected by the use of IPM.

Conclusions

Based on our findings, we conclude that the use of IPM in minimally invasive liver resection is safe and feasible for patients with HCC, including those with compensated liver cirrhosis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00423-021-02361-z.

Impact of Advancing Age on the Status and Risk of Postoperative Infections After Liver Resection

BACKGROUND

Despite the recently increasing number of elderly patients undergoing liver resection, the impact of advancing age on postoperative infections (PIs) incidence and risk remains unclear. This study aimed to investigate the impact of advancing age on PIs incidence and status.

METHODS

This retrospective study included 744 patients undergoing liver resection without biliary reconstruction or combined resection of other organs. Multivariable analysis with a restricted cubic spline was used to evaluate the impact of advancing age on PIs and to determine its association with PIs risk in patients undergoing open and laparoscopic liver resection (OLR and LLR, respectively).

RESULTS

Multivariable analysis demonstrated that advancing age was significantly associated with increased PIs risk (P = 0.017). The spline curve showed that the odds ratio for PIs sharply increased starting approximately at 65 years of age. Unadjusted restricted cubic splines assessing the subcategories of PIs demonstrated that advancing age was associated with increased risks of organ/space surgical site infection and sepsis (P = 0,064 and 0.048, respectively). Multivariable analysis revealed that LLR was associated with the lower PIs risk compared with OLR (P = 0.025), whereas the lower PIs risk with LLR was not significantly obscured by advancing age (P = 0.29).

CONCLUSIONS

Advancing age was associated with increased risk of PIs, including organ/space surgical site infections and sepsis, after liver resection especially in patients aged ≥ 65 years.

Inter-surgeon variability is associated with likelihood to undergo minimally invasive hepatectomy and postoperative mortality

INTRODUCTION

Minimally invasive liver surgery (MILS) has been increasingly adopted in clinical practice; yet, inter-surgeon variability in operative approach (MILS vs. open), as well as the impact of providers on the likelihood of undergoing MILS have not been well characterized.

METHODS

The Medicare 100% Standard Analytic Files were reviewed to identify Medicare beneficiaries who underwent hepatectomy between 2013 - 2017. The impact of patient- and procedure- related factors on the likelihood of MILS was investigated.

RESULTS

Overall 12,110 (91.6%) patients underwent open liver resection, while 1,112 (8.4%) patients had MILS. Based on total MILS volume, surgeons were categorized into average (1-3 cases), above average (4-7 cases) and high (>8 or more cases) MILS volume surgeons. While male patients (OR = 0.85, 95%CI 0.75-0.97) were less likely to undergo MILS, patients operated on more recently (year 2017; OR = 1.72, 95%CI 1.38-2.14) for a cancer indication (OR = 1.23, 95%CI 1.05-1.42) had a higher chance of MILS. After controlling for patient- and procedure-related characteristics, there was almost a two-fold variation in the odds that a patient underwent MILS versus open hepatectomy based on the individual surgeon provider (MOR = 1.75, 95%CI 1.48-1.99). Patients who had a MILS performed by a high-volume MILS surgeon had 36% lower odds of death within 90-days (OR = 0.64, 95%CI 0.51-0.79).

CONCLUSION

The likelihood of undergoing MILS, as well as post-operative mortality, was heavily influenced by the individual surgeon provider rather than patient- or procedure-related factors.

Minimally Invasive Hepatectomy in North America: Laparoscopic Versus Robotic

BACKGROUND

Minimally invasive hepatectomy has been shown to be associated with improved outcomes when compared with open surgery. However, data comparing laparoscopic and robotic hepatectomy is lacking and limited to single-center studies.

METHODS

Patients undergoing major (≥ 3 segments) or partial (≤ 2 segments) hepatectomy were identified in the 2014-2017 ACS-NSQIP hepatectomy targeted database. Patients undergoing laparoscopic and robotic approaches were compared, and propensity score matching was utilized to adjust for bias.

RESULTS

Of 3152 minimally invasive hepatectomies (MIHs), 86% (N = 2706) were partial and 14% (N = 446) were major. The laparoscopic approach was utilized in 92% of patients (N = 2905) and 8% were performed robotically (N = 247). The percentage of MIHs increased over time (p < 0.01). After matching, 240 were identified in each cohort. Compared with the robotic approach, patients undergoing laparoscopic hepatectomy had a significantly higher conversion rate (23% vs. 7.4%) but had shorter operative time (159 vs. 204 min) (p < 0.001). Laparoscopic cases undergoing an unplanned conversion to open were associated with increased morbidity (p < 0.001), but this difference was not observed in robotic cases. Both MIH approaches had low mortality (1.0%, p = 1.00), overall morbidity (17%, p = 0.47), and very short length of stay (3 days, p = 0.80).

CONCLUSION

Minimally invasive hepatectomy is performed primarily for partial hepatectomies. Laparoscopic hepatectomy is associated with a significantly higher conversion rate, and converted cases have worse outcomes. Both minimally invasive approaches are safe with similar mortality, morbidity, and a very short length of stay. Graphical Abstract.

Minimally Invasive Hepatectomy in North America: Laparoscopic Versus Robotic

BACKGROUND

Minimally invasive hepatectomy has been shown to be associated with improved outcomes when compared with open surgery. However, data comparing laparoscopic and robotic hepatectomy is lacking and limited to single-center studies.

METHODS

Patients undergoing major (≥ 3 segments) or partial (≤ 2 segments) hepatectomy were identified in the 2014-2017 ACS-NSQIP hepatectomy targeted database. Patients undergoing laparoscopic and robotic approaches were compared, and propensity score matching was utilized to adjust for bias.

RESULTS

Of 3152 minimally invasive hepatectomies (MIHs), 86% (N = 2706) were partial and 14% (N = 446) were major. The laparoscopic approach was utilized in 92% of patients (N = 2905) and 8% were performed robotically (N = 247). The percentage of MIHs increased over time (p < 0.01). After matching, 240 were identified in each cohort. Compared with the robotic approach, patients undergoing laparoscopic hepatectomy had a significantly higher conversion rate (23% vs. 7.4%) but had shorter operative time (159 vs. 204 min) (p < 0.001). Laparoscopic cases undergoing an unplanned conversion to open were associated with increased morbidity (p < 0.001), but this difference was not observed in robotic cases. Both MIH approaches had low mortality (1.0%, p = 1.00), overall morbidity (17%, p = 0.47), and very short length of stay (3 days, p = 0.80).

CONCLUSION

Minimally invasive hepatectomy is performed primarily for partial hepatectomies. Laparoscopic hepatectomy is associated with a significantly higher conversion rate, and converted cases have worse outcomes. Both minimally invasive approaches are safe with similar mortality, morbidity, and a very short length of stay. Graphical Abstract.

Surgical outcomes of 118 complex laparoscopic liver resections: a single- center experience

BACKGROUND

Indications for laparoscopic liver resection (LLR) are continuously expanding. The Japanese Society of Hepato-Biliary-Pancreatic Surgery defines highly difficult hepatectomy as a procedure involving one or more sections (except for left lateral sectionectomy) or anatomical segmentectomy. This study aimed to assess the outcomes of complex LLR procedures and compare their technical difficulties, about which only a little is known to date.

METHODS

We performed a retrospective review of the operative outcomes of 118 consecutive patients who underwent pure laparoscopic complex hepatectomy. The surgical outcomes, including operative times, blood loss amounts, and postoperative morbidity rates, were compared among complex LLR procedures.

RESULTS

The overall median operative time was 280 minutes, and the median intraoperative blood loss was 86 mL. Two patients required conversion to open laparotomy (1.7%). The postoperative major morbidity rate was 11.0% Posterosuperior segmentectomy, right hemihepatectomy, and anterior sectionectomy required the longest operative times. Anterior and posterior sectionectomy resulted in the highest blood loss, and right hemihepatectomy and anterior sectionectomy resulted in the most complications.

CONCLUSIONS

The surgical difficulties associated with complex LLR procedures vary. It is critical to recognize the specific risks and cautionary points to ensure patient safety and provide proper systemic training to surgeons.

Effects of both Pro- and Synbiotics in Liver Surgery and Transplantation with Special Focus on the Gut-Liver Axis-A Systematic Review and Meta-Analysis

The gut-liver axis is of upmost importance for the development of infections after surgery. Further bacterial translocation due to surgery-related dysbiosis is associated with limited detoxification function of the liver compromising outcome of surgical therapy. After liver surgery, about 30% of patients develop a bacterial infection, with the risk of bacteremia or even sepsis-associated liver failure and mortality in >40%. The potential benefit of pro-/synbiotics given before surgery is still under debate. Thus, a systematic literature search on trials comparing patients with or without supplementation and outcome after liver resection or transplantation was performed. Our search strategy revealed 12 relevant studies on perioperative administration of pro-/synbiotics in liver surgery. The pro-/synbiotic combinations and concentrations as well as administration timeframes differed between studies. Five studies were performed in liver transplantation and 7 in liver resection. All studies but one reported lower infection rates (pooled RR: 0.46, 95% CI: 0.31–0.67) with pro-/synbiotics. Liver function was assessed after LT/LR in 3 and 5 studies, respectively. Pro-/synbiotics improved function in 1/3 and 2/5 studies, respectively. Concluding, perioperative pro-/synbiotics clearly reduce infection after liver surgery. However, standard protocols with both well-defined probiotic strain preparations and administration timeframes are pending.

Contemporary indications for and outcomes of hepatic resection for neuroendocrine liver metastases

BACKGROUND

Although surgical resection is associated with the best long-term outcomes for neuroendocrine liver metastases (NELM), the current indications for and outcomes of surgery for NELM from a population perspective are not well understood.

AIM

To determine the current indications for and outcomes of liver resection (LR) for NELM using a population-based cohort.

METHODS

A retrospective review of the 2014-2017 American College of Surgeons National Surgical Quality Improvement Program and targeted hepatectomy databases was performed to identify patients who underwent LR for NELM. Perioperative characteristics and 30-d morbidity and mortality were analyzed.

RESULTS

Among 669 patients who underwent LR for NELM, the median age was 60 (interquartile range: 51-67) and 51% were male. While the number of metastases resected ranged from 1 to 9, the most common (45%) number of tumors resected was one. The majority (68%) of patients had a largest tumor size of < 5 cm. Most patients underwent partial hepatectomy (71%) while fewer underwent a right or left hepatectomy or trisectionectomy. The majority of operations were open (82%) versus laparoscopic (17%) or robotic (1%). In addition, 30% of patients underwent intraoperative ablation while 45% had another concomitant operation including cholecystectomy (28.8%), bowel resection (20.2%), or partial pancreatectomy (3.4%). Overall 30-d morbidity and mortality was 29% and 1.3%, respectively. On multivariate analysis, American Society of Anesthesiologists class ≥ 3 [odds ratios (OR), OR = 2.089, 95% confidence intervals (CI): 1.197-3.645], open approach (OR = 1.867, 95%CI: 1.148-3.036), right hepatectomy (OR = 1.618, 95%CI: 1.014-2.582), and prolonged operative time of > 230 min (OR = 1.731, 95%CI: 1.168-2.565) were associated with higher 30-d morbidity while intraoperative ablation and concomitant procedures were not.

CONCLUSION

LR for NELM was performed with relatively low postoperative morbidity and mortality. Concomitant procedures performed at the time of LR did not increase morbidity.

Association between intraoperative nociception and postoperative complications in patients undergoing laparoscopic gastrointestinal surgery

A higher degree of surgical invasiveness, which increases intraoperative nociception, might induce postoperative complications. Although several nociceptive indices for use during surgery are available in clinical practice, association between intraoperative nociception and postoperative complications has not been reported. An index representing intraoperative nociception, which is the averaged value of Nociceptive Response throughout the surgery (mean NR) was applied to examine the association in the present study. The retrospective study evaluated consecutive adult patients undergoing laparoscopic gastrointestinal surgery, American Society of Anesthesiologists-physical status (ASA-PS) I or II, whose preoperative C-reactive protein level was < 0.3 mg dL^-1. We first used ordinal logistic analysis to examine the association between preoperative and intraoperative risk factors and complications graded by the Clavien-Dindo classification. Next, we performed propensity score matched analysis to evaluate the effects of mean NR throughout surgery on postoperative complications. Ordinal logistic analysis (n = 158) revealed that duration of surgery (P < 0.001), mean NR during surgery (P = 0.002), and ASA-PS (P = 0.016) were risk factors for postoperative complications. Then all patients were divided into two propensity score matched groups, based on a mean NR of < 0.85 and ≥ 0.85, with matching for age, ASA-PS, body mass index and duration of surgery. The severity of postoperative complications was significantly higher in the high NR group than in the low NR group (P = 0.005). In conclusion, there was likely an association between intraoperative nociception and postoperative complications in patients without serious preoperative conditions and comorbidities.