Effect of triclosan-coated sutures for abdominal wound closure on the incidence of abdominal wound dehiscence: a protocol for an individual participant data meta-analysis.

INTRODUCTION: Acute abdominal wound dehiscence (AWD) or burst abdomen is a severe complication after abdominal surgery with an incidence up to 3.8%. Surgical site infection (SSI) is the biggest risk factor for the development of AWD. It is strongly suggested that the use of triclosan-coated sutures (TCS) for wound closure reduces the risk of SSI. We hypothesise that the use of TCS for abdominal wound closure may reduce the risk of AWD. Current randomised controlled trials (RCTs) lack power to investigate this. Therefore, the purpose of this individual participant data meta-analysis is to evaluate the effect of TCS for abdominal wound closure on the incidence of AWD. METHODS AND ANALYSIS: We will conduct a systematic review of Medline, Embase and Cochrane Central Register of Controlled Trials for RCTs investigating the effect of TCS compared with non-coated sutures for abdominal wound closure in adult participants scheduled for open abdominal surgery. Two independent reviewers will assess eligible studies for inclusion and methodological quality. Authors of eligible studies will be invited to collaborate and share individual participant data. The primary outcome will be AWD within 30 days after surgery requiring reoperation. Secondary outcomes include SSI, all-cause reoperations, length of hospital stay and all-cause mortality within 30 days after surgery. Data will be analysed with a one-step approach, followed by a two-step approach. In the one-step approach, treatment effects will be estimated as a risk ratio with corresponding 95% CI in a generalised linear mixed model framework with a log link and binomial distribution assumption. The quality of evidence will be judged using the Grading of Recommendations Assessment Development and Evaluation approach. ETHICS AND DISSEMINATION: The medical ethics committee of the Amsterdam UMC, location AMC in the Netherlands waived the necessity for a formal approval of this study, as this research does not fall under the Medical Research involving Human Subjects Act. Collaborating investigators will deidentify data before sharing. The results will be submitted to a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42019121173.

Influence of diabetes on short-term outcome after major hepatectomy: an underestimated risk?

BACKGROUND: Patient-related risk factors such as diabetes mellitus and obesity are increasing in western countries. At the same time the indications for liver resection in both benign and malignant diseases have been significantly extended in recent years. Major liver resection is performed more frequently in a patient population of old age, comorbidity and high rates of neoadjuvant chemotherapy. The aim of this study was to evaluate whether diabetes mellitus, obesity and overweight are risk factors for the short-term post-operative outcome after major liver resection. METHODS: Four hundred seventeen major liver resections (≥ 3 segments) were selected from a prospective database. Exclusion criteria were prior liver resection in patient's history and synchronous major intra-abdominal procedures. Overweight was defined as BMI ≥ 25 kg/m2 and < 30 kg/m2 and obesity as BMI ≥ 30 kg/m2. Primary end point was 90-day mortality and logistic regression was used for multivariate analysis. Secondary end points included morbidity, complications according to Clavien-Dindo classification, unplanned readmission, bile leakage, and liver failure. Morbidity was defined as occurrence of a post-operative complication during hospital stay or within 90 days postoperatively. RESULTS: Fifty-nine patients had diabetes mellitus (14.1%), 48 were obese (11.6%) and 147 were overweight (35.5%). There were no statistically significant differences in mortality rates between the groups. In the multivariate analysis, diabetes was an independent predictor of morbidity (OR = 2.44, p = 0.02), Clavien-Dindo grade IV complications (OR = 3.6, p = 0.004), unplanned readmission (OR = 2.44, p = 0.04) and bile leakage (OR = 2.06, p = 0.046). Obese and overweight patients did not have an impaired post-operative outcome compared patients with normal weight. CONCLUSIONS: Diabetes has direct influence on the short-term postoperative outcome with an increased risk of morbidity but not mortality. Preoperative identification of high-risk patients will potentially decrease complication rates and allow for individual patient counseling as part of a shared decision-making process. For obese and overweight patients, major liver resection is a safe procedure.

Prospective study to evaluate the prognostic value of different nutritional assessment scores in liver surgery: NURIMAS Liver (DRKS00006340).

BACKGROUND: Malnutrition is recognised as a preoperative risk factor for patients undergoing hepatic resection. It is important to identify malnourished patients and take preventive therapeutic action before surgery. However, there is no evidence regarding which existing nutritional assessment score (NAS) is best suited to predict outcomes of liver surgery. METHODS: All patients scheduled for elective liver resection at the surgical department of the University Hospital of Heidelberg and the Municipal Hospital of Karlsruhe were screened for eligibility. Twelve NASs were calculated before operation, and patients were categorised according to each score as being either at risk or not at risk for malnutrition. The association of malnutrition according to each score and occurrence of at least one major complication was the primary endpoint, which was achieved using a multivariate logistic regression analysis including established risk factors in liver surgery as covariates. RESULTS: The population consisted of 182 patients. The percentage of patients deemed malnourished by the NAS varied among the different scores, with the lowest being 2.20% (Mini Nutritional Assessment) and the highest 52.20% (Nutritional Risk Classification). Forty patients (22.0%) had a major complication. None of the scores were significantly associated with major complications. CONCLUSIONS: None of the twelve investigated NAS defined a state of malnutrition that was independently associated with postoperative complications. Other means of measuring malnutrition in liver surgery should be investigated prospectively.

Comparison of score-based prediction of 90-day mortality after liver resection.

BACKGROUND: Indications for liver surgery are expanding fast and complexity of procedures increases. Preoperative mortality risk assessment by scoring systems is debatable. A previously published externally validated Mortality Risk Score allowed easy applicable and precise prediction of postoperative mortality. Aim of the study was to compare the performance of the Mortality Risk Score with the standard scores MELD and P-POSSUM. METHODS: Data of 529 patients undergoing liver resection were analysed. Mortality Risk Score, the labMELD Score and the P-POSSUM Scores (PS, OS, P-POSSUM mortality %) were calculated. The ROC curves of the three scoring systems were computed and the areas under the curve (C-index) were calculated using logistic regression models. Comparisons between the ROC curves were performed using the corresponding Wald tests. RESULTS: Internal validation confirmed that the risk model was predictive for a 90-day mortality rate with a C-index of 0.8421. The labMELD Score had a C-index of 0.7352 and the P-POSSUM system 0.6795 (PS 0.6953, OS 0.5413). The 90-day mortality rate increased with increasing labMELD values (p < 0.0001). Categorized according to the Mortality Risk Score Groups the labMELD Score showed a linear increase while the POSSUM Scores showed variable results. CONCLUSIONS: By accurately predicting the risk of postoperative mortality after liver surgery the Mortality Risk Score should be useful at the selection stage. Prediction can be adjusted by use of the well-established labMELD Score. In contrast, the performance of standard P-POSSUM Scores is limited.

Risk assessment for liver resection.

BACKGROUND: In recent years, the profile for patients undergoing complex liver resections has changed, with mortality rates remaining generally stable. With these factors in mind, the objective of this study was to evaluate the variables associated with surgical outcomes after hepatectomy and identify groups at high risk for postoperative mortality. METHODS: The records of 1,796 patients who underwent liver resection of more than one liver segment at the Department of General and Transplantation Surgery, University Hospital Heidelberg, Germany, were analyzed. The primary end point was a 90-day in-hospital mortality. Logistic regression analyses were performed to identify risk factors associated with mortality. A risk score was created in accordance with weighted points based on the odds ratios obtained from multivariate logistic regression analyses. External validation of the score was performed, using data derived from 281 patients at the board-certified center for liver surgery in Karlsruhe, Germany. RESULTS: The overall patient morbidity rate (Clavien-Dindo Grade II or greater) was 32%. The 30- and 90-day mortality rates were 3.0% and 4.5%, respectively. In multivariate analysis, factors independently associated with risk for 90-day in-hospital mortality were age ≥60 years (OR 3.71), ASA classification III (OR 2.94), ASA IV (15.66), perihilar cholangiocarcinoma (OR 5.65), intrahepatic cholangiocarcinoma (OR 3.08), INR ≥ 1.1 (OR 2.43), g-GT ≥ 60 U/L (OR 2.86), platelet count ≤ 120/nL (OR 5.52), creatinine ≥ 2 mg/dL (OR 9.85), and right trisectionectomy (OR 2.88). The 90-day mortality-risk score that was created based on these factors effectively stratified patients into very low risk (0-1 points, 0.2% mortality rate in 662 patients), low risk (2-3 points, 2.9% mortality rate in 769 patients), medium risk (4-5 points, 14.7% mortality rate in 232 patients), and high risk (≥6 points, 33% mortality rate in 57 patients) groups (P < .0001). As a performance metric, the C-index for the proposed risk score for 90-day mortality was 0.86; whereas external validation revealed that this C-index was 0.89 (P = .0002). CONCLUSION: Based on patient-related factors and procedure-specific variables, the proposed preoperative-risk score can be used to identify high-risk patients to determine 90-day mortality after liver resection.

Histopathological changes resulting from selective internal radiotherapy (SIRT).

BACKGROUND: Selective internal radiotherapy (SIRT) has emerged as an effective therapy for patients with liver malignancies. Here, we report our analysis of histopathological changes in tumors and healthy liver tissue after SIRT and liver resection. Our main intent was to determine if specific histopathological changes occur in tumor and normal liver tissues. METHODS: We identified 17 patients in whom SIRT was applied to achieve liver resectability. Samples were taken from the resected liver tissue. The tumor, tumor peripheries, and tumor-free tissue were examined microscopically. RESULTS: Microspheres were identified in the vascular tumor bed, tumor-free liver, and portal tract. More microspheres were detected in the tumor than in the healthy liver tissue. When the effects of SIRT were analyzed, most patients showed a partial pathological response. Specific histopathological changes could not be described. We did not find any typical signs of radiation-induced hepatitis in healthy liver tissue. CONCLUSIONS: Our findings support the clinical experience of effective tumor control after SIRT together with minimal impairment of healthy liver tissue. The observed histopathological changes suggest that SIRT might play a role in preoperative downsizing of liver malignancies.