Comparison of two-dimensional measurement with three-dimensional volume rendering for the assessment of loss of domain in incisional hernia patients

PURPOSE

We aimed to compare simple two-dimensional (2D) measurement with comprehensive three-dimensional (3D) volume rendering to determine loss of domain (LOD), a clinically important decision-making feature for incisional hernia repair.

METHODS

In this single-center retrospective study, we analyzed the CT scans of a consecutive cohort of adult patients with a midline incisional hernia. The hernia sac- and abdominal cavity volumes were obtained by two different methods. The 2D method estimated the volumes using the corresponding height, width, and depth. The 3D method comprised of a volume rendering tool. For both methods, LOD was calculated according to the Sabbagh ratio (hernia sac volume / (hernia sac volume + abdominal cavity volume)). Taking the 3D method as the reference standard, the performance of the 2D method was expressed as positive predictive value (PPV) and negative predictive value (NPV) for LOD of more than- and less than 20%. The agreement between both methods was expressed as Cohen's kappa coefficient (kappa).

RESULTS

We analyzed 92 CT scans. Agreement between both methods was high (kappa = 0.854, p = 0.0001); all 67 measurements for which the 2D method assessed LOD to be less than 20% were correctly classified (NPV = 100%), and 20 of 25 measurements for which the 2D method assessed LOD to be more than 20% were correctly classified (PPV = 80%).

CONCLUSIONS

The 2D method can exclude patients from perioperative actions needed for a more complex hernia. Since this method is easy to use and less time-consuming, it seems useful for the routine radiological assessment of LOD in clinical practice.

Efficacy of different preoperative skin antiseptics on the incidence of surgical site infections: a systematic review, GRADE assessment, and network meta-analysis

BACKGROUND

Surgical site infection (SSI) is the most common postoperative complication and substantially increases health-care costs. Published meta-analyses and international guidelines differ with regard to which preoperative skin antiseptic solution and concentration has the highest efficacy. We aimed to compare the efficacy of different skin preparation solutions and concentrations for the prevention of SSIs, and to provide an overview of current guidelines.

METHODS

This systematic review and network meta-analysis compared different preoperative skin antiseptics in the prevention of SSIs in adult patients undergoing surgery of any wound classification. We searched for randomised controlled trials (RCTs) in MEDLINE, Embase, and Cochrane CENTRAL, published up to Nov 23, 2021, that directly compared two or more antiseptic agents (ie, chlorhexidine, iodine, or olanexidine) or concentrations in aqueous and alcohol-based solutions. We excluded paediatric, animal, and non-randomised studies, and studies not providing standard preoperative intravenous antibiotic prophylaxis. Studies with no SSIs in both groups were excluded from the quantitative analysis. Two reviewers screened and reviewed eligible full texts and extracted data. The primary outcome was the occurrence of SSI (ie, superficial, deep, and organ space). We conducted a frequentist random effects network meta-analysis to estimate the network effects of the skin preparation solutions on the prevention of SSIs. A risk-of-bias and Grading of Recommendations, Assessment, Development, and Evaluation assessment were done to determine the certainty of the evidence. This study is registered with PROSPERO, CRD42021293554.

FINDINGS

Overall, 2326 articles were identified, 33 studies were eligible for the systematic review, and 27 studies with 17 735 patients reporting 2144 SSIs (overall incidence of 12·1%) were included in the quantitative analysis. Only 2·0-2·5% chlorhexidine in alcohol (relative risk 0·75, 95% CI 0·61-0·92) and 1·5% olanexidine (0·49, 0·26-0·92) significantly reduced the rate of SSIs compared with aqueous iodine. For clean surgery, we found no difference in efficacy between different concentrations of chlorhexidine in alcohol. Seven RCTs were at high risk of bias, 24 had some concerns, and two had low risk of bias. Heterogeneity across the studies was moderate (I²=27·5%), and netsplitting did not show inconsistencies between direct and indirect comparisons. Five of ten studies that mentioned adverse events related to the skin preparation solutions reported no adverse events, and five reported a total of 56 mild events (mainly erythema, pruritus, dermatitis, skin irritation, or mild allergic symptoms); none reported a substantial difference in adverse events between groups.

INTERPRETATION

For adult patients undergoing a surgical procedure of any wound classification, skin preparation using either 2·0-2·5% chlorhexidine in alcohol or 1·5% olanexidine is most effective in the prevention of SSIs. For clean surgery, no specific concentration of chlorhexidine in alcohol can be recommended. The efficacy of olanexidine was established by a single randomised trial and further investigation is needed.

FUNDING

Dutch Association for Quality Funds Medical Specialists.

Risk Factor-Driven Prehabilitation Prior to Abdominal Wall Reconstruction to Improve Postoperative Outcome. A Narrative Review

All abdominal wall reconstructions find themselves on a scale, varying between simple to highly complex procedures. The level of complexity depends on many factors that are divided into patient comorbidities, hernia characteristics, and wound characteristics. Preoperative identification of modifiable risk factors provides the opportunity for patient optimization. Because this so called prehabilitation greatly improves postoperative outcome, reconstructive surgery should not be scheduled before all modifiable risk factors are optimized to a point where no further improvement can be expected. In this review, we discuss the importance of preoperative risk factor recognition, identify modifiable risk factors, and utilize options for patient prehabilitation, all aiming to improve postoperative outcome and therewith long-term success of the reconstruction.

A Network Meta-Analysis and GRADE Assessment of the Effect of Preoperative Oral Antibiotics with and Without Mechanical Bowel Preparation on Surgical Site Infection Rate in Colorectal Surgery

Objective

To compare the effect of different methods of bowel preparation on the incidence of surgical site infections (SSI), anastomotic leakage (AL), and mortality in patients undergoing elective colorectal surgery.

Background

Recent guidelines advise mechanical bowel preparation with oral antibiotics (MBP-OA) for the prevention of SSI in colorectal surgery. Recent trials suggest oral antibiotics (OA) alone may be sufficient.

Methods

PubMed, MEDLINE, and Embase were searched from inception until 10-08-2021. We included randomized controlled trials (RCTs) comparing multiple methods of bowel preparation (mechanical bowel preparation [MBP], OA, MBP-OA, or no preparation) with regards to clinical outcomes such as incidence of SSI, AL, and mortality rates. A frequentist random-effects network meta-analysis was conducted to estimate the network effects of the different treatment options.

Results

We included 48 studies with 13,611 patients. Compared to no preparation, combined direct and indirect network estimates showed a relative risk (RR) for SSI of 0.57 (95% confidence interval [CI], 0.45-0.72) for MBP-OA, 0.68 (95% CI, 0.49-0.95) for OA, and 1.05 (95% CI, 0.87-1.26) for MBP. The RR for MBP-OA compared to OA was 0.84 (95% CI, 0.60-1.19); in sensitivity analysis of mainly laparoscopic procedures this effect of MBP-OA was more profound (RR, 0.56; 95% CI, 0.31-0.99).

Conclusions

This network meta-analysis of RCTs finds that both mechanical bowel preparation with oral antibiotics and oral antibiotics alone are comparably effective in the prevention of SSI. The evidence is uncertain about the relative benefit of MBP-OA compared to OA alone. Therefore, it seems justified to use either of the 2 for the prevention of SSI in colorectal surgery.

Endoscopic Versus Surgical Step-Up Approach for Infected Necrotizing Pancreatitis (ExTENSION): Long-term Follow-up of a Randomized Trial

BACKGROUND & AIMS

Previous randomized trials, including the Transluminal Endoscopic Step-Up Approach Versus Minimally Invasive Surgical Step-Up Approach in Patients With Infected Pancreatic Necrosis (TENSION) trial, demonstrated that the endoscopic step-up approach might be preferred over the surgical step-up approach in patients with infected necrotizing pancreatitis based on favorable short-term outcomes. We compared long-term clinical outcomes of both step-up approaches after a period of at least 5 years.

METHODS

In this long-term follow-up study, we reevaluated all clinical data on 83 patients (of the originally 98 included patients) from the TENSION trial who were still alive after the initial 6-month follow-up. The primary end point, similar to the TENSION trial, was a composite of death and major complications. Secondary end points included individual major complications, pancreaticocutaneous fistula, reinterventions, pancreatic insufficiency, and quality of life.

RESULTS

After a mean follow-up period of 7 years, the primary end point occurred in 27 patients (53%) in the endoscopy group and in 27 patients (57%) in the surgery group (risk ratio [RR], 0.93; 95% confidence interval [CI], 0.65-1.32; P = .688). Fewer pancreaticocutaneous fistulas were identified in the endoscopy group (8% vs 34%; RR, 0.23; 95% CI, 0.08-0.83). After the initial 6-month follow-up, the endoscopy group needed fewer reinterventions than the surgery group (7% vs 24%; RR, 0.29; 95% CI, 0.09-0.99). Pancreatic insufficiency and quality of life did not differ between groups.

CONCLUSIONS

At long-term follow-up, the endoscopic step-up approach was not superior to the surgical step-up approach in reducing death or major complications in patients with infected necrotizing pancreatitis. However, patients assigned to the endoscopic approach developed overall fewer pancreaticocutaneous fistulas and needed fewer reinterventions after the initial 6-month follow-up. Netherlands Trial Register no: NL8571.

Perioperative care bundles for the prevention of surgical-site infections: meta-analysis

BACKGROUND

Care bundles are used widely to prevent surgical-site infections (SSIs). Recent systematic reviews suggested larger effects from bundles with more interventions. These reviews were largely based on uncontrolled before-after studies and did not consider their biases. The aim of this meta-analysis was to determine the effectiveness of care bundles to prevent SSIs and explore characteristics of effective care bundles.

METHODS

A systematic review, reanalysis, and meta-analysis of available evidence were undertaken. RCTs, controlled before-after studies, and uncontrolled before-after studies with sufficient data for reanalysis as interrupted time series studies (ITS) were eligible. Studies investigating the use of a care bundle, with at least one intraoperative intervention, compared with standard care were included.

RESULTS

Four RCTs, 1 controlled before-after study, and 13 ITS were included. Pooled data from RCTs were heterogeneous. Meta-analysis of ITS resulted in a level change of -1.16 (95 per cent c.i.-1.78 to -0.53), indicating a reduction in SSI. The effect was larger when the care bundle comprised a higher proportion of evidence-based interventions. Meta-regression analyses did not show statistically significant associations between effect estimates and number of interventions, number of evidence-based interventions, or proportion of evidence-based interventions.

CONCLUSION

Meta-analysis of ITS indicated that perioperative care bundles prevent SSI.This effect is inconsistent across RCTs. Larger bundles were not associated with a larger effect, but the effect may be larger if the care bundle contains a high proportion of evidence-based interventions. No strong evidence for characteristics of effective care bundles was identified.

Whole-exome Sequencing Identifies SLC52A1 and ZNF106 Variants as Novel Genetic Risk Factors for (Early) Multiple-organ Failure in Acute Pancreatitis

OBJECTIVE

The aim of this study was to identify genetic variants associated with early multiple organ failure (MOF) in acute pancreatitis.

SUMMARY BACKGROUND DATA

MOF is a life-threatening complication of acute pancreatitis, and risk factors are largely unknown, especially in early persistent MOF. Genetic risk factors are thought to enhance severity in complex diseases such as acute pancreatitis.

METHODS

A 2-phase study design was conducted. First, we exome sequenced 9 acute pancreatitis patients with early persistent MOF and 9 case-matched patients with mild edematous pancreatitis (phenotypic extremes) from our initial Dutch cohort of 387 patients. Secondly, 48 candidate variants that were overrepresented in MOF patients and 10 additional variants known from literature were genotyped in a replication cohort of 286 Dutch and German patients.

RESULTS

Exome sequencing resulted in 161,696 genetic variants, of which the 38,333 non-synonymous variants were selected for downstream analyses. Of these, 153 variants were overrepresented in patients with multiple-organ failure, as compared with patients with mild acute pancreatitis. In total, 58 candidate variants were genotyped in the joined Dutch and German replication cohort. We found the rs12440118 variant of ZNF106 to be overrepresented in patients with MOF (minor allele frequency 20.4% vs 11.6%, Padj=0.026). Additionally, SLC52A1 rs346821 was found to be overrepresented (minor allele frequency 48.0% vs 42.4%, Padj= 0.003) in early MOF. None of the variants known from literature were associated.Conclusions: This study indicates that SLC52A1, a riboflavin plasma membrane transporter, and ZNF106, a zinc finger protein, may be involved in disease progression toward (early) MOF in acute pancreatitis.

Laparoscopic peritoneal lavage versus sigmoidectomy for perforated diverticulitis with purulent peritonitis: three-year follow-up of the randomised LOLA trial

Background

This study aimed to compare laparoscopic lavage and sigmoidectomy as treatment for perforated diverticulitis with purulent peritonitis during a 36 month follow-up of the LOLA trial.

Methods

Within the LOLA arm of the international, multicentre LADIES trial, patients with perforated diverticulitis with purulent peritonitis were randomised between laparoscopic lavage and sigmoidectomy. Outcomes were collected up to 36 months. The primary outcome of the present study was cumulative morbidity and mortality. Secondary outcomes included reoperations (including stoma reversals), stoma rates, and sigmoidectomy rates in the lavage group.

Results

Long-term follow-up was recorded in 77 of the 88 originally included patients, 39 were randomised to sigmoidectomy (51%) and 38 to laparoscopic lavage (49%). After 36 months, overall cumulative morbidity (sigmoidectomy 28/39 (72%) versus lavage 32/38 (84%), p = 0·272) and mortality (sigmoidectomy 7/39 (18%) versus lavage 6/38 (16%), p = 1·000) did not differ. The number of patients who underwent a reoperation was significantly lower for lavage compared to sigmoidectomy (sigmoidectomy 27/39 (69%) versus lavage 17/38 (45%), p = 0·039). After 36 months, patients alive with stoma in situ was lower in the lavage group (proportion calculated from the Kaplan–Meier life table, sigmoidectomy 17% vs lavage 11%, log-rank p = 0·0268). Eventually, 17 of 38 (45%) patients allocated to lavage underwent sigmoidectomy.

Conclusion

Long-term outcomes showed that laparoscopic lavage was associated with less patients who underwent reoperations and lower stoma rates in patients alive after 36 months compared to sigmoidectomy. No differences were found in terms of cumulative morbidity or mortality. Patient selection should be improved to reduce risk for short-term complications after which lavage could still be a valuable treatment option.

Graphical abstract

Clinical outcomes of open abdominal wall reconstruction with the use of a polypropylene reinforced tissue matrix: a multicenter retrospective study

Objective

To assess mesh behaviour and clinical outcomes of open complex abdominal wall reconstruction (CAWR) with the use of a polypropylene reinforced tissue matrix.

Methods

A multicenter retrospective study of adult patients who underwent open CAWR with the use of a permanent polypropylene reinforced tissue matrix (OviTex^®) between June 2019 and January 2021.

Results

Fifty-five consecutive patients from four hospitals in the Netherlands were analysed; 46 patients with a ventral hernia and 9 patients with an open abdomen. Most patients with a ventral hernia had one or more complicating comorbidities (91.3%) and one or more complicating hernia characteristics (95.7%). Most procedures were performed in a (clean) contaminated surgical field (69.6% CDC 2–4; 41.3% CDC 3–4). All nine patients with an open abdomen underwent semi-emergent surgery. Twelve out of 46 patients with a ventral hernia (26.1%) and 4 of 9 patients with an open abdomen (44.4%) developed a postoperative surgical site infection that made direct contact with the mesh as confirmed on computed tomography (CT), suspicious of mesh infection. No patient needed mesh explantation for persistent infection of the mesh. During a median follow-up of 13 months, 4 of 46 ventral hernia patients (8.7%) developed a CT confirmed hernia recurrence.

Conclusion

Polypropylene reinforced tissue matrix can withstand infectious complications and provides acceptable mid-term recurrence rates in this retrospective study on open complex abdominal wall reconstructions. Longer follow-up data from prospective studies are required to determine further risk of hernia recurrence.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10029-022-02604-y.

Optimising diagnostics to discriminate complicated from uncomplicated appendicitis: a prospective cohort study protocol

INTRODUCTION

Growing evidence is showing that complicated and uncomplicated appendicitis are two different entities that may be treated differently. A correct diagnosis of the type of appendicitis is therefore essential. The Scoring system of Appendicitis Severity (SAS) combines clinical, laboratory and imaging findings. The SAS rules out complicated appendicitis in 95% (negative predictive value, NPV) and detects 95% (sensitivity) of patients with complicated appendicitis in adults suspected of acute appendicitis. However, this scoring system has not yet been validated externally. In this study, we aim to provide a prospective external validation of the SAS in a new cohort of patients with clinical suspicion of appendicitis. We will optimise the score when necessary.

METHODS AND ANALYSIS

The SAS will be validated in 795 consecutive adult patients diagnosed with acute appendicitis confirmed by imaging. Data will be collected prospectively in multiple centres. The predicted diagnosis based on the SAS score will be compared with the combined surgical and histological diagnosis. Diagnostic accuracy for ruling out complicated appendicitis will be calculated. If the SAS does not reach a sensitivity and NPV of 95% in its present form, the score will be optimised. After optimisation, a second external validation will be performed in a new group of 328 patients. Furthermore, the diagnostic accuracy of the clinical perspective of the treating physician for differentiation between uncomplicated and complicated appendicitis and the patient's preferences for different treatment options will be assessed.

ETHICS AND DISSEMINATION

Ethical approval was granted by the Amsterdam UMC Medical Ethics Committee (reference W19_416 # 19.483). Because of the observational nature of this study, the study does not fall under the scope of the Medical Research Involving Human Subjects Act. Results will be presented in peer-reviewed journals. This protocol is submitted for publication before analysis of the results.

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.

Delphi Consensus on Intraoperative Technical/Surgical Aspects to Prevent Surgical Site Infection after Colorectal Surgery

BACKGROUND

Previous studies have focused on the development and evaluation of care bundles to reduce the risk of surgical site infection (SSI) throughout the perioperative period. A focused examination of the technical/surgical aspects of SSI reduction during CRS has not been conducted. This study aimed to develop an expert consensus on intraoperative technical/surgical aspects of SSI prevention by the surgical team during colorectal surgery (CRS).

STUDY DESIGN

In a modified Delphi process, a panel of 15 colorectal surgeons developed a consensus on intraoperative technical/surgical aspects of SSI prevention undertaken by surgical personnel during CRS using information from a targeted literature review and expert opinion. Consensus was developed with up to three rounds per topic, with a prespecified threshold of ≥70% agreement.

RESULTS

In 3 Delphi rounds, the 15 panelists achieved consensus on 16 evidence-based statements. The consensus panel supported the use of wound protectors/retractors, sterile incision closure tray, preclosure glove change, and antimicrobial sutures in reducing SSI along with wound irrigation with aqueous iodine and closed-incision negative pressure wound therapy in high-risk, contaminated wounds.

CONCLUSIONS

Using a modified Delphi method, consensus has been achieved on a tailored set of recommendations on technical/surgical aspects that should be considered by surgical personnel during CRS to reduce the risk of SSI, particularly in areas where the evidence base is controversial or lacking. This document forms the basis for ongoing evidence for the topics discussed in this article or new topics based on newly emerging technologies in CRS.

Re-Assessment in Patients with Suspected Acute Appendicitis

Background: The effect of diagnosing appendicitis at re-assessment on post-operative outcomes is not clear. This study aims to compare patients diagnosed with appendicitis at initial presentation versus patients who were diagnosed at re-assessment. Patients and Methods: Data from the Dutch SNAPSHOT appendicitis collaborative was used. Patients with appendicitis who underwent appendectomy were included. Effects of diagnosis at re-assessment were compared with diagnosis at initial presentation. Primary outcomes were the proportion of patients with complicated appendicitis and the post-operative complication rate. Results: Of 1,832 patients, 245 (13.4%) were diagnosed at re-assessment. Re-assessed patients had a post-operative complication rate comparable to those diagnosed with appendicitis at initial presentation (15.1% vs. 12.7%; p = 0.29) and no substantial difference was found in the proportion of patients with complicated appendicitis (27.9% vs. 33.5%; p = 0.07). For patients with complicated appendicitis, more post-operative complications were seen if diagnosed at re-assessment than if diagnosed initially (38.2% vs. 22.9%; p = 0.006). Conclusions: For patients in whom appendicitis was not diagnosed at first presentation, but at re-assessment, both the proportion of complicated appendicitis and the post-operative complication rate were comparable to those who were diagnosed with appendicitis at initial presentation. However, re-assessed patients with complicated appendicitis encountered more post-operative complications.

Preoperative serum ADAM12 levels as a stromal marker for overall survival and benefit of adjuvant therapy in patients with resected pancreatic and periampullary cancer

BACKGROUND

We evaluated the stroma marker A Disintegrin And Metalloprotease 12 (ADAM12) as a preoperative prognostic and treatment-predictive marker for overall survival (OS) in pancreatic ductal adenocarcinoma (PDAC) and periampullary cancers.

METHODS

Materials were derived from the prospective nationwide Dutch Pancreas Biobank (2015-2017). We included patients who underwent resection because of PDAC/periampullary cancer or non-invasive IPMN (control group) and had a preoperative serum sample available. ADAM12 levels were dichotomized using a pre-defined cut-off (316 pg/mL). Univariable and multivariable Cox regression analyses (backward selection) were performed.

RESULTS

Median ADAM12 levels were 161 (IQR 79-352) pg/mL in 215 PDAC and periampullary adenocarcinomas. High ADAM12 levels (>316 pg/mL) predicted poor OS in the total group of pancreatic and periampullary adenocarcinomas (P = 0.04), but not after adjustment. In distal cholangiocarcinoma (n = 33), high ADAM12 levels predicted poor OS in univariable analysis (P = 0.02), but not in PDAC (P = 0.63). PDAC patients (n = 135) with high ADAM12 levels benefited from adjuvant treatment (median OS 27 vs 14 months, P = 0.02), whereas those with low levels did not (21 vs 21 months, P = 0.87).

CONCLUSION

High circulating ADAM12 levels, as a proxy for activated stroma, predict survival benefit from adjuvant chemotherapy in PDAC, requiring validation in future studies.

Immediate versus Postponed Intervention for Infected Necrotizing Pancreatitis

BACKGROUND

Infected necrotizing pancreatitis is a potentially lethal disease that is treated with the use of a step-up approach, with catheter drainage often delayed until the infected necrosis is encapsulated. Whether outcomes could be improved by earlier catheter drainage is unknown.

METHODS

We conducted a multicenter, randomized superiority trial involving patients with infected necrotizing pancreatitis, in which we compared immediate drainage within 24 hours after randomization once infected necrosis was diagnosed with drainage that was postponed until the stage of walled-off necrosis was reached. The primary end point was the score on the Comprehensive Complication Index, which incorporates all complications over the course of 6 months of follow-up.

RESULTS

A total of 104 patients were randomly assigned to immediate drainage (55 patients) or postponed drainage (49 patients). The mean score on the Comprehensive Complication Index (scores range from 0 to 100, with higher scores indicating more severe complications) was 57 in the immediate-drainage group and 58 in the postponed-drainage group (mean difference, -1; 95% confidence interval [CI], -12 to 10; P = 0.90). Mortality was 13% in the immediate-drainage group and 10% in the postponed-drainage group (relative risk, 1.25; 95% CI, 0.42 to 3.68). The mean number of interventions (catheter drainage and necrosectomy) was 4.4 in the immediate-drainage group and 2.6 in the postponed-drainage group (mean difference, 1.8; 95% CI, 0.6 to 3.0). In the postponed-drainage group, 19 patients (39%) were treated conservatively with antibiotics and did not require drainage; 17 of these patients survived. The incidence of adverse events was similar in the two groups.

CONCLUSIONS

This trial did not show the superiority of immediate drainage over postponed drainage with regard to complications in patients with infected necrotizing pancreatitis. Patients randomly assigned to the postponed-drainage strategy received fewer invasive interventions. (Funded by Fonds NutsOhra and Amsterdam UMC; POINTER ISRCTN Registry number, ISRCTN33682933.).

Epithelial argininosuccinate synthetase is dispensable for intestinal regeneration and tumorigenesis

The epithelial signaling pathways involved in damage and regeneration, and neoplastic transformation are known to be similar. We noted upregulation of argininosuccinate synthetase (ASS1) in hyperproliferative intestinal epithelium. Since ASS1 leads to de novo synthesis of arginine, an important amino acid for the growth of intestinal epithelial cells, its upregulation can contribute to epithelial proliferation necessary to be sustained during oncogenic transformation and regeneration. Here we investigated the function of ASS1 in the gut epithelium during tissue regeneration and tumorigenesis, using intestinal epithelial conditional Ass1 knockout mice and organoids, and tissue specimens from colorectal cancer patients. We demonstrate that ASS1 is strongly expressed in the regenerating and Apc-mutated intestinal epithelium. Furthermore, we observe an arrest in amino acid flux of the urea cycle, which leads to an accumulation of intracellular arginine. However, loss of epithelial Ass1 does not lead to a reduction in proliferation or increase in apoptosis in vivo, also in mice fed an arginine-free diet. Epithelial loss of Ass1 seems to be compensated by altered arginine metabolism in other cell types and the liver.

Timing of Preoperative Antibiotic Prophylaxis and Surgical Site Infection: TAPAS, An Observational Cohort Study

OBJECTIVE

To test the hypothesis that surgical site infection (SSI) risk differs, after administration of surgical antibiotic prophylaxis (SAP) within 60-30 or 30-0 minutes before incision.

BACKGROUND

The importance of appropriate timing of SAP before surgery has long been recognized. However, available evidence is contradictive on the best timing within a 60-0 minutes time interval before incision. Here, we aim to evaluate previous contradictions with a carefully designed observational cohort.

METHODS

An observational cohort study was conducted in a Dutch tertiary referral center. For 2 years, consecutive patients with SAP indication undergoing general, orthopedic, or gynecologic surgery were followed for the occurrence of superficial and deep SSI as defined by the Center of Disease Control and Prevention. The association between timing of SAP and SSI was assessed using multivariable logistic regression.

RESULTS

After 3001 surgical procedures, 161 SSIs were detected. In 87% of the procedures, SAP was administered within 60 minutes before incision. Only antibiotics with short infusion time were used. Multivariable logistic regression indicated there was no conclusive evidence of a difference in SSI risk after SAP administration 60-30 minutes or 30-0 minutes before incision [odds ratio: 0.82; 95% confidence interval (0.57-1.19)].

CONCLUSIONS

For SAP with short infusion time no clear superior timing interval within the 60-minute interval before incision could be identified in this cohort. We were unable to reproduce differences in SSI risk found in earlier studies.

WSES/GAIS/SIS-E/WSIS/AAST global clinical pathways for patients with intra-abdominal infections

Intra-abdominal infections (IAIs) are common surgical emergencies and have been reported as major contributors to non-trauma deaths in hospitals worldwide. The cornerstones of effective treatment of IAIs include early recognition, adequate source control, appropriate antimicrobial therapy, and prompt physiologic stabilization using a critical care environment, combined with an optimal surgical approach. Together, the World Society of Emergency Surgery (WSES), the Global Alliance for Infections in Surgery (GAIS), the Surgical Infection Society-Europe (SIS-E), the World Surgical Infection Society (WSIS), and the American Association for the Surgery of Trauma (AAST) have jointly completed an international multi-society document in order to facilitate clinical management of patients with IAIs worldwide building evidence-based clinical pathways for the most common IAIs. An extensive non-systematic review was conducted using the PubMed and MEDLINE databases, limited to the English language. The resulting information was shared by an international task force from 46 countries with different clinical backgrounds. The aim of the document is to promote global standards of care in IAIs providing guidance to clinicians by describing reasonable approaches to the management of IAIs.

A systematic review and meta-analysis of technical aspects and clinical outcomes of botulinum toxin prior to abdominal wall reconstruction

Purpose

To systematically review technical aspects and treatment regimens of botulinum toxin A (BTA) injections in the lateral abdominal wall musculature. We also investigated the effect of BTA on abdominal muscle- and hernia dimensions, and clinical outcome.

Methods

PubMed, EMBASE, CENTRAL, and CINAHL were searched for studies that investigate the injection of BTA in the lateral abdominal wall muscles. Study characteristics, BTA treatment regimens, surgical procedures, and clinical outcomes are presented descriptively. The effect of BTA on muscle- and hernia dimensions is analyzed using random-effects meta-analyses, and exclusively for studies that investigate ventral incisional hernia patients.

Results

We identified 23 studies, comprising 995 patients. Generally, either 500 units of Dysport^® or 200–300 units of Botox^® are injected at 3–5 locations bilaterally in all three muscles of the lateral abdominal wall, about 4 weeks prior to surgery. No major procedural complications are reported. Meta-analyses show that BTA provides significant elongation of the lateral abdominal wall of 3.2 cm per side (95% CI 2.0–4.3, I² = 0%, p < 0.001); 6.3 cm total elongation, and a significant but heterogeneous decrease in transverse hernia width (95% CI 0.2–6.8, I² = 94%, p = 0.04). Furthermore, meta-analysis shows that BTA pretreatment in ventral hernia patients significantly increases the fascial closure rate [RR 1.08 (95% CI 1.02–1.16, I² = 0%, p = 0.02)].

Conclusion

The injection technique and treatment regimens of botulinum toxin A as well as patient selection require standardization. Bilateral pretreatment in hernia patients significantly elongates the lateral abdominal wall muscles, making fascial closure during surgical hernia repair more likely.

Study registration

A review protocol for this meta-analysis was registered at PROSPERO (CRD42020198246).

Supplementary Information

The online version contains supplementary material available at 10.1007/s10029-021-02499-1.

Microbiota composition and mucosal immunity in patients with asymptomatic diverticulosis and controls

INTRODUCTION

The etiology of diverticulosis is still poorly understood. However, in patients with diverticulitis, markers of mucosal inflammation and microbiota alterations have been found. The aim of this study was to evaluate potential differences of the gut microbiota composition and mucosal immunity between patients with asymptomatic diverticulosis and controls.

METHODS

We performed a prospective study on patients who underwent routine colonoscopy for causes not related to diverticular disease or inflammatory bowel disease. Participants were grouped based on the presence or absence of diverticula. Mucosal biopsies were obtained from the sigmoid and transverse colon. Microbiota composition was analyzed with IS-pro, a 16S-23S based bacterial profiling technique. To predict if patients belonged to the asymptomatic diverticulosis or control group a partial least squares discriminant analysis (PLS-DA) regression model was used. Inflammation was assessed by neutrophil and lymphocyte counts within the taken biopsies.

RESULTS

Forty-three patients were enrolled. Intestinal microbiota profiles were highly similar within individuals for all phyla. Between individuals, microbiota profiles differed substantially but regardless of the presence (n = 19) of absence (n = 24) of diverticula. Microbiota diversity in both sigmoid and transverse colon was similar in all participants. We were not able to differentiate between diverticulosis patients and controls with a PLS-DA model. Mucosal lymphocyte counts were comparable among both groups; no neutrophils were detected in any of the studied biopsies.

CONCLUSIONS

Microbiota composition and inflammatory markers were comparable among asymptomatic diverticulosis patients and controls. This suggests that the gut microbiota and mucosal inflammation do not play a major role in the pathogenesis of diverticula formation.

Spatioregional assessment of the gut microbiota in experimental necrotizing pancreatitis

BACKGROUND

Infectious complications following experimental pancreatitis involve major disruptions in the gut microbiota. The aim of this study was to characterize this disruption by examining the spatioregional distribution in microbial community structure and function following experimental pancreatitis associated with pancreatic infection.

METHODS

Mice were subjected to infusion of the pancreatic duct with either taurocholate to induce necrotizing pancreatitis or normal saline (control group). The spatial (lumen versus mucosa) and regional composition and function of the microbiota from the duodenum, ileum, caecum, colon, pancreas and blood were evaluated using 16S rRNA gene amplicon sequencing.

RESULTS

Mice that developed necrotizing pancreatitis demonstrated a decrease in microbial richness and significantly altered microbiota in distal parts of the gastrointestinal tract, compared with controls. Among the most differentially increased taxa were the mucus-degrading Akkermansia muciniphila, and there was a decrease of butyrate-producing bacteria following pancreatitis. Application of the SourceTracker tool to the generated metadata indicated that the duodenum was the most probable source of bacteria that subsequently infected pancreatic tissue in this model. The functional prediction annotation using pathway analyses indicated a diminished capacity of the caecal microbiota to metabolize carbohydrate, and fatty and amino acids.

DISCUSSION

The distal gut microbiota was significantly impacted in this model of experimental necrotizing pancreatitis. Data suggest that the duodenal microbiota might also play a role in bacterial translation and secondary infections.

Pain patterns in chronic pancreatitis: a nationwide longitudinal cohort study

OBJECTIVE

Pain in chronic pancreatitis is subdivided in a continuous or intermittent pattern, each thought to represent a different entity, requiring specific treatment. Because evidence is missing, we studied pain patterns in a prospective longitudinal nationwide study.

DESIGN

1131 patients with chronic pancreatitis (fulfilling M-ANNHEIM criteria) were included between 2011 and 2018 in 30 Dutch hospitals. Patients with continuous or intermittent pain were compared for demographics, pain characteristics, quality of life (Short-Form 36), imaging findings, disease duration and treatment. Alternation of pain pattern and associated variables were longitudinally assessed using a multivariable multinomial logistic regression model.

RESULTS

At inclusion, 589 patients (52%) had continuous pain, 231 patients (20%) had intermittent pain and 311 patients (28%) had no pain. Patients with continuous pain had more severe pain, used more opioids and neuropathic pain medication, and had a lower quality of life. There were no differences between pain patterns for morphological findings on imaging, disease duration and treatment. During a median follow-up of 47 months, 552 of 905 patients (61%) alternated at least once between pain patterns. All alternations were associated with the Visual Analogue Scale pain intensity score and surgery was only associated with the change from pain to no pain.

CONCLUSION

Continuous and intermittent pain patterns in chronic pancreatitis do not seem to be the result of distinctly different pathophysiological entities. The subjectively reported character of pain is not related to imaging findings or disease duration. Pain patterns often change over time and are merely a feature of how severity of pain is experienced.