Systematic reviews and meta-analysis for the surgeon scientist

A systematic review and meta-analysis of primary bypass surgery compared with bypass surgery after endovascular treatment in peripheral artery disease patients

OBJECTIVE

Both bypass surgery and endovascular treatment are well-recognized interventions for the treatment of peripheral artery disease; however, the effect of failed endovascular treatment on subsequent surgeries remains controversial. A systematic review was conducted to compare the outcomes of primary bypass and bypass surgery after endovascular treatment.

METHODS

Three academic databases (Embase, PubMed, and Scopus) were searched from their inception to August 2022. Two independent investigators searched for studies that reported the outcomes of primary bypass surgery and bypass surgery after endovascular treatment in patients with peripheral artery disease. Abstracts and full-text studies were screened independently using duplicate data abstraction. Dichotomous outcome measures were reported using a random-effects model to generate a summary odds ratio (OR) and 95% confidence interval (CI). The risk of bias was assessed using the Newcastle-Ottawa Scale.

RESULTS

Seventeen retrospective observational studies were selected from 3911 articles and included 8064 patients, 6252 of whom underwent primary bypass surgery and 1812 underwent bypass surgery after endovascular treatment. The mean age was 69.0 years and 61.2% (n = 4938) were male. For perioperative outcomes, the 30-day results showed no difference in mortality (OR, 0.76; 95% CI, 0.53-1.10), or amputation (OR, 0.89; 95% CI, 0.67-1.20). For short- to mid-term outcomes, primary patency did not differ at 6 months (OR, 0.98; 95% CI, 0.81-1.19), 1 year (OR, 1.12; 95% CI, 0.97-1.30), or 2 years (OR, 1.17; 95% CI, 0.85-1.61) follow-up. Amputation-free survival did not differ at 6 months (OR, 1.03; 95% CI, 0.82-1.30), 1 year (OR, 1.09; 95% CI, 0.89-1.32), 2 years (OR, 1.18; 95% CI, 0.93-1.50), or 3 years (OR, 1.09; 95% CI, 0.84-1.40) of follow-up. No significant difference was found in overall survival or second patency.

CONCLUSIONS

This meta-analysis of retrospective, nonrandomized, observational studies suggests that prior endovascular treatment of lower extremity arterial disease does not result in worse perioperative, short-term, or mid-term clinical outcomes of subsequent infrainguinal bypass surgery compared with patients without prior endovascular treatment.

Circulating long non-coding RNAs as novel diagnostic biomarkers for Alzheimer's disease (AD): A systematic review and meta-analysis

BACKGROUND

Long non-coding RNAs (lncRNAs) have been reported to be involved in the pathogenesis of neurodegenerative diseases. It has also been hypothesized that plasma exosomal lncRNAs may be used as Alzheimer's disease (AD) biomarkers. In this systematic review, we compiled all studies on the subject to evaluate the accuracy of lncRNAs in identifying AD cases through meta-analysis.

METHODS

A PRISMA-compliant systematic search was conducted in PubMed/MEDLINE, EMBASE, and Web of Science databases for English publications till September 2022. We included all observational studies published which investigated the sensitivity and specificity of various lncRNAs in plasma samples of AD diagnosis. Our search strategy included lncRNA and all the related spelling and abbreviation variations combined with the keyword Alzheimer's disease. Methodological quality was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines and the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-II) tool. The meta-analysis was carried out using the area under the Receiver Operator Characteristic (ROC) curves (AUC) and sensitivity and specificity values to assess the accuracy of the identified lncRNAs in AD diagnosis. To account for the predicted heterogeneity of the study, a random-effects model was used. All the statistical analyses and visualizations were conducted using Stata 17.0 software.

RESULTS

A total of seven studies (AD patients = 553, healthy controls = 513) were included in the meta-analysis. Three lncRNAs were upregulated (RNA BACE-AS1, RNA NEAT1, RNA GAS5), and one lncRNA (MALAT1) was downregulated in plasma samples of AD patients. RNA 51A and RNA BC200 were reported to have variable expression patterns. A lncRNA (RNA 17A) was not significantly different between AD and control groups. The pooled sensitivity, specificity, and AUC values of lncRNAs in identifying AD were (0.74; 95% CI [0.63, 0.82], I2 = 79.2%), (0.88; 95% CI [0.75, 0.94], I2 = 88.9%), and 0.86; 95% CI [0.82, 0.88], respectively. In addition, the pooled diagnostic odds ratio (DOR) of the five individual lncRNAs in AD diagnosis was 20.

CONCLUSION

lncRNAs had high accuracy in identifying AD and must be seen as a promising diagnostic biomarker of the disease.

Circulating microRNA-208 family as early diagnostic biomarkers for acute myocardial infarction: A meta-analysis

OBJECTIVE

Many recent studies have demonstrated that serum miRNA-208 (miR-208) could be a powerful biomarker in the early diagnosis of acute myocardial infarction (AMI). However, the result of previous studies was not accurate due to the small sample sizes and controversial issues. Therefore, this study was performed to investigate the relationship between the expression levels of miR-208 and AMI.

MATERIALS AND METHODS

According to the inclusion and exclusion criteria, a preliminary literature search was performed. The study was based on articles published in PubMed, Embase, Cochrane databases before September 30, 2019. Two staff members extracted data from the included articles for meta-analysis. These data were analyzed for sensitivity, specificity, diagnostic odds ratio, and summary receiver operator curve (SROC) analyses.

RESULTS

This study included 13 pieces of literature, which contains 1703 patients with AMI and 1589 controls. The main results of our meta-analysis were as follows: The pool sensitivity and specificity of miR-208 for diagnosing AMI was 83% and 97%. The area under the SROC curve (AUC) was 93%. Mir-208 had a highly effective diagnostic capacity to distinguish AMI from chest pain patients with an AUC of 93%.

CONCLUSIONS

The results showed that circulating miR-208 was a reliable biomarker both for diagnosting ST-elevation myocardial infarction (STEMI) and non-ST elevation myocardial infarction (NSTEMI). MiR-208 was sufficient to distinguish AMI patients with chest pain from healthy controls.

Following the trend in maxillofacial surgery literature

Evidence-based medicine relies on the integration of high-quality research with clinical expertise and patient values. The hierarchy of evidence allows the clinician to assign value to research based on the methodological quality of the study design and its applicability to the clinical question. Improvements in the quality of research in oral and maxillofacial surgery aim to strengthen evidence-based medicine and patient care. Analysis of the trends in maxillofacial surgery publications can identify the strengths and weaknesses of the current body of research, and direct researchers to areas that require improvement. The aim of this study was to review the proportion of the types of articles published in the British Journal of Oral and Maxillofacial Surgery (BJOMS) and the International Journal of Oral and Maxillofacial Surgery (IJOMS) between January 2010 and December 2019. These data were compared with a previously published review that summarised the proportion published in 2000 - 2009. The topics chosen for meta-analysis and the number of qualitative studies were also summarised. In total, 4931 articles were reviewed over the 10-year period. Compared with the previous 10 years, there was an increase in randomised controlled trials and meta-analyses, and a reduction in case series and case reports. Implantology and dentoalveolar surgery were the most common topics chosen for meta-analysis. Overall, the trend in the maxillofacial literature is towards a higher quality body of research.

Pyoderma Gangrenosum in Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

BACKGROUND

Pyoderma gangrenosum (PG) is an uncommon but severe extra-intestinal manifestation (EIM) of inflammatory bowel disease (IBD). The incidence and risk factors for PG are disputed.

AIMS

To assess the incidence of PG and identify factors associated with PG in IBD patients.

METHODS

A search of electronic databases (Ovid and PubMed) was conducted between 1966 and 2019. Studies that calculated the incidence of PG in IBD patient cohorts were included. Patient demographics, IBD subtype, and EIM presence were recorded. A review of our institutional database of 1057 IBD patients was conducted. A multivariate regression model and meta-analysis were conducted to identify risk factors for PG. A random effects model was used to combine the data of included studies.

RESULTS

Fourteen studies were included in addition to 1057 IBD patients and 26 PG cases from the Louisville cohort. In total, there were 379 cases of PG in the cumulative cohort of 61,695 IBD patients. The PG incidence in individual studies ranged from 0.4 to 2.6%. In the institutional cohort, ocular EIMs and a permanent stoma were significant risk factors for PG. In the meta-analysis, PG was associated with female gender (RR = 1.328, 95% CI 1.161-1.520), Crohn's disease (RR = 1.193, 95% CI 1.001-1.422), erythema nodosum (RR = 9.281, 95% CI 6.081-14.164), and ocular EIM (RR = 4.55, 95% CI 3.04-6.81). There was study heterogeneity when assessing IBD subtype, ocular, and joint EIMs.

CONCLUSIONS

There are conflicting data on the incidence and risk factors for PG. This meta-analysis confirms an association between PG and female gender, Crohn's disease, erythema nodosum, and ocular EIM that have been described in smaller studies.

Value of Blood-Based microRNAs in the Diagnosis of Acute Myocardial Infarction: A Systematic Review and Meta-Analysis

Background: Recent studies have shown that blood-based miRNAs are dysregulated in patients with acute myocardial infarction (AMI) and are therefore a potential tool for the diagnosis of AMI. Therefore, this study summarized and evaluated studies focused on microRNAs as novel biomarkers for the diagnosis of AMI from the last ten years. Methods: MEDLINE, the Cochrane Central database, and EMBASE were searched between January 2010 and December 2019. Studies that assessed the diagnostic accuracy of circulating microRNAs in AMI were chosen. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the curve (AUC) were used to assess the test performance of miRNAs. Results: A total of 58 studies that included 8,206 participants assessed the diagnostic accuracy of circulating miRNAs in AMI. The main results of the meta-analyses are as follows: (1) Total miRNAs: the overall pooled sensitivity and specificity were 0.82 (95% CI: 0.79-0.85) and 0.87 (95% CI: 0.84-0.90), respectively. The AUC value was 0.91 (95% CI: 0.88-0.93) in the overall summary receiver operator characteristic (SROC) curve. (2) The panel of two miRNAs: sensitivity: 0.88 (95% CI: 0.77-0.94), specificity: 0.84 (95% CI: 0.72-0.91), AUC: 0.92 (95% CI: 0.90-0.94). (3) The panel of three miRNAs: sensitivity: 0.91 (95% CI: 0.85-0.94), specificity: 0.87 (95% CI: 0.77-0.92), AUC: 0.92 (95% CI: 0.89-0.94). (4) Results by types of miRNAs: miRNA-1: sensitivity: 0.78 (95% CI: 0.71-0.84), specificity: 0.86 (95% CI: 0.77-0.91), AUC: 0.88 (95% CI: 0.85-0.90); miRNA-133a: sensitivity: 0.85 (95% CI: 0.69-0.94), specificity: 0.92 (95% CI: 0.61-0.99), AUC: 0.93 (95% CI: 0.91-0.95); miRNA-208b: sensitivity: 0.80 (95% CI: 0.69-0.88), specificity: 0.96 (95% CI: 0.77-0.99), AUC: 0.91 (95% CI: 0.88-0.93); miRNA-499: sensitivity: 0.85 (95% CI: 0.77-0.91), specificity: 0.95 (95% CI: 0.89-0.98), AUC: 0.96 (95% CI: 0.94-0.97). Conclusion: miRNAs may be used as potential biomarkers for the detection of AMI. For single, stand-alone miRNAs, miRNA-499 may have better diagnostic accuracy compared to other miRNAs. We propose that a panel of multiple miRNAs with high sensitivity and specificity should be tested.

Long non-coding RNA (lncRNA) and epithelial-mesenchymal transition (EMT) in colorectal cancer: a systematic review

BACKGROUND

Colorectal cancer (CRC) is a leading cause of cancer-related death. Epithelial-mesenchymal transition (EMT) is a major process in tumor metastasis development. This systematic review aims to describe the role of long non-coding RNA (lncRNA) in EMT in CRC.

METHODS

The electronic databases, PubMed, Cochrane, and EMBASE, were searched from January1990 to June 2019 to identify studies examining lncRNA and their role in mediating EMT in CRC. Studies examining clinical specimens and/or in vitro experiments were included.

RESULTS

In 61 identified studies, 54 lncRNAs were increased in CRC compared to normal colorectal epithelium. Increased lncRNA expression was frequently associated with worse survival. Many lncRNAs mediate their effect through competitive endogenous RNA or transcription factor regulation. The ZEB1, 2/E-cadherin, Wnt/β-catenin signaling, and chromatin remodeling pathways are discussed in particular.

CONCLUSIONS

lncRNAs are major regulators of EMT and predictor adverse outcome in CRC patients. Future research must focus on delineating lncRNA function prior to potential clinical use.

MicroRNA-371-3 cluster as biomarkers for the diagnosis and prognosis of cancers

Purpose: To date, increasing evidences have demonstrated that the aberrant expression of miR-371–3 cluster has been verified in various cancers and could be potentially used as a biomarker for tumor diagnosis and prognosis. To explore the role of miR-371–3 cluster in tumor diagnosis and prognosis, we conducted this study based on the published data.

Methods: We searched electronic databases (PubMed, EMBASE and Web of Science databases) (Jan 1, 2007 to Jun 1, 2018). The pooled sensitivity, specificity and area under the curve (AUC) of summary receiver operator characteristic (SROC) curve were used for diagnostic values, meanwhile the pooled hazard ration (HR) and 95% CI were used to explore the prognosis capacity of miR-372 and miR-373. In addition, the publication bias of the enrolled studies was tested and a sensitivity analysis of each study was performed to evaluate the stability of the pooled result.

Results: A total of eleven eligible studies containing six eligible studies containing 870 participants for diagnosis and 1218 cancer cases for prognosis were selected for this study. For diagnosis, the pooled results revealed that the miR-371 (sensitivity: 0.85, specificity: 0.92, AUC: 0.92) and miR-373 (sensitivity: 0.81, specificity: 0.93, AUC: 0.93) could be used as diagnostic biomarkers. For prognosis, we observed that elevated miR-372 indicated poor prognosis (HR=2.31, 95% CI: 1.04–5.14), especially in the cutoff value subgroup of median (HR=2.62, 95% CI: 1.54–4.46). In addition, pooled results showed that expression of miR-373 was not related to prognosis because of the significant heterogeneity, and the high miR-373 expression presented favorable prognosis in Asians (HR=0.34, 95% CI: 0.23–0.50) after omitting the study of heterogeneity origin.

Conclusion: The current studies demonstrated that miR-371 and miR-373 could be predictive tumor diagnostic biomarkers and the expression of miR-372 and miR-373 may indicate prognosis of cancer patients.

Methods to systematically review and meta-analyse observational studies: a systematic scoping review of recommendations

Background

Systematic reviews and meta-analyses of observational studies are frequently performed, but no widely accepted guidance is available at present. We performed a systematic scoping review of published methodological recommendations on how to systematically review and meta-analyse observational studies.

Methods

We searched online databases and websites and contacted experts in the field to locate potentially eligible articles. We included articles that provided any type of recommendation on how to conduct systematic reviews and meta-analyses of observational studies. We extracted and summarised recommendations on pre-defined key items: protocol development, research question, search strategy, study eligibility, data extraction, dealing with different study designs, risk of bias assessment, publication bias, heterogeneity, statistical analysis. We summarised recommendations by key item, identifying areas of agreement and disagreement as well as areas where recommendations were missing or scarce.

Results

The searches identified 2461 articles of which 93 were eligible. Many recommendations for reviews and meta-analyses of observational studies were transferred from guidance developed for reviews and meta-analyses of RCTs. Although there was substantial agreement in some methodological areas there was also considerable disagreement on how evidence synthesis of observational studies should be conducted. Conflicting recommendations were seen on topics such as the inclusion of different study designs in systematic reviews and meta-analyses, the use of quality scales to assess the risk of bias, and the choice of model (e.g. fixed vs. random effects) for meta-analysis.

Conclusion

There is a need for sound methodological guidance on how to conduct systematic reviews and meta-analyses of observational studies, which critically considers areas in which there are conflicting recommendations.

Electronic supplementary material

The online version of this article (10.1186/s12874-018-0495-9) contains supplementary material, which is available to authorized users.

The prognostic impact of abdominal surgery in cancer patients with neutropenic enterocolitis: a systematic review and meta-analysis, on behalf the Groupe de Recherche en Réanimation Respiratoire du patient d'Onco-Hématologie (GRRR-OH)

Neutropenic enterocolitis (NE) is a diagnostic and therapeutic challenge associated with high mortality rates, with controversial opinions on its optimal management. Physicians are usually reluctant to select surgery as the first-choice treatment, concerns being raised regarding the potential risks associated with abdominal surgery during neutropenia. Nevertheless, no published studies comforted this idea, literature is scarce and surgery has never been compared to medical treatment. This review and meta-analysis aimed to determine the prognostic impact of abdominal surgery on outcome of neutropenic cancer patients presenting with NE, versus medical conservative treatment. This meta-analysis included studies analyzing cancer patients presenting with NE, treated with surgical or medical treatment, searched by PubMed and Cochrane databases (1983–2016), according to PRISMA recommendations. The endpoint was hospital mortality. Fixed-effects models were used. The meta-analysis included 20 studies (385 patients). Overall estimated mortality was 42.2% (95% CI = 40.2–44.2). Abdominal surgery was associated with a favorable outcome with an OR of 0.41 (95% CI = 0.23–0.74; p = 0.003). Pre-defined subgroups analysis showed that neither period of admission, underlying malignancy nor neutropenia during the surgical procedure, influenced this result. Surgery was not associated with an excess risk of mortality compared to medical treatment. Defining the optimal indications of surgical treatment is needed.

Trial registration PROSPERO CRD42016048952

The effect of time to post-operative weightbearing on functional and clinical outcomes in adults with a displaced intra-articular calcaneal fracture; A systematic review and pooled analysis

BACKGROUND

Post-operative weightbearing guidelines for displaced intra-articular calcaneal fractures (DIACF) have been pragmatically developed in the past, however hardly adapted to current health care insights. A period of six to nine weeks of non-weightbearing is usually recommended. It is unknown whether an earlier start of weightbearing is advisable.

OBJECTIVES

The primary aim was to evaluate the effect of time to post-operative weightbearing on Böhler's angle. Secondary aims were to determine the effect on functional outcome (e.g., The American Orthopedic Foot and Ankle Society Scale), post-operative pain score, complications (e.g., infections, nonunion, implant removal), and revision surgeries. Finally, the effect of bone void filling on these outcomes was investigated.

DATA SOURCE

A literature search was performed on January 24, 2017 in the Cochrane Library, Medline Ovid, Embase, Web of Science, Google Scholar, and CINAHL.

LITERATURE SELECTION

Studies reporting on operatively treated patients with a DIACF and time to weightbearing were eligible for inclusion. Studies were excluded when not reporting primary data, solely reporting on open fractures, bilateral fractures, or polytrauma patients. Based upon the time to starting partial weightbearing, patient cohorts were stratified into very early (0-4 weeks), early (4-6 weeks), intermediate (6-8 weeks), or late (8-12 weeks) start of partial weightbearing.

DATA EXTRACTION

Two investigators extracted data independently using a predefined data sheet.

RESULTS

After applying exclusion criteria, 72 studies remained eligible for analysis. Böhler's and Gissane's angles, calcaneal height, AOFAS, pain scores, and complications had overlapping confidence intervals in all weightbearing groups.

CONCLUSION

The adverse sequelae which are assumed to be associated with starting partial weightbearing already within six weeks after internal fixation of calcaneal fractures, is not supported by literature data. This systematic review suggests that early weightbearing does not result in impaired outcomes compared with more conservative weightbearing regimes.

Functional outcomes of distal radius fractures with and without ulnar styloid fractures: a meta-analysis

The aim of this meta-analysis was to compare the functional outcomes of patients with a distal radius fracture with and without a concomitant fracture of the ulnar styloid process. A systematic literature search was performed to identify all studies comparing patients with a distal radius fracture with and without an ulnar styloid process fracture. The initial search revealed 511 articles, of which 12 articles with a total of 2243 patients were included; 1196 patients with and 1047 patients without an ulnar styloid process fracture. A statistically significant mean difference of 3.40 points (95% CI 1.33-5.48) in the Disability of the Arm, Shoulder, and Hand score was found in favour of patients without an ulnar styloid process fracture. This difference is less than 10 and therefore not clinically important. No significant difference was found in Patient-Rated Wrist Evaluation scores, range of motion, grip strength, visual analogue scale pain scores, ulnar-sided wrist pain and distal radio-ulnar joint instability between patients with and without an ulnar styloid process fracture after 1 year of follow-up. Moreover, no significant differences were found between ulnar styloid base and nonbase fractures.

LEVEL OF EVIDENCE

I.

High-dose vs. Low-dose Proton Pump Inhibitors post-endoscopic hemostasis in patients with bleeding peptic ulcer. A meta-analysis and meta-regression analysis

BACKGROUND/AIMS

Present meta-analysis aims to evaluate studies of low- versus high-dose proton pump Inhibitors (PPI) post-endoscopic hemostasis, including the newly published randomized controlled trials (RCTs) and to conclude whether low-dose PPI can generate the comparable results as high-dose PPI.

MATERIALS AND METHODS

To identify suitable trials, the electronic databases PubMed, Medline, Cochrane Library, and the Embase were used. All RCTs concerning low- versus high-dose PPI administration post-endoscopic hemostasis published until December 2016 were identified. Primary outcomes were rebleeding rates, need for surgical intervention, and mortality.

RESULTS

Studies included a total of 1.651 participants. There were significantly less cases of rebleeding in the low-dose PPI treatment arm (p=0.003). All but one study provided data concerning need for Surgical Intervention and Mortality. The respective effect sizes were [odds ratio (OR), 95% confidence intervals (CI): 1.35, 0.72-2.53] and [OR, 95% CI: 1.20, 0.70-2.05]. Both treatment arms were comparable considering the aforementioned outcomes (p=0.35 and p=0.51, respectively). Meta-regression analysis likewise unveiled comparable outcomes between studies using pantoprazole versus lansoprazole concerning all three outcomes [rebleeding (p=0.944), surgical intervention (p=0.884), and mortality (p=0.961)].

CONCLUSION

A low-dose PPI treatment is equally effective as a high-dose PPI treatment following endoscopic arresting of bleeding. However, we anticipate the completion of more high-quality RCTs that will embrace distinct ethnicities, standardized endoscopic diagnosis and management, double-blind strategies, and appraisal of results working specific standards over clear-cut follow-up periods.

Short-term clinical outcomes of laparoscopic vs open rectal excision for rectal cancer: A systematic review and meta-analysis

AIM

To review evidence on the short-term clinical outcomes of laparoscopic (LRR) vs open rectal resection (ORR) for rectal cancer.

METHODS

A systematic literature search was performed using Cochrane Central Register, MEDLINE, EMBASE, Scopus, OpenGrey and ClinicalTrials.gov register for randomized clinical trials (RCTs) comparing LRR vs ORR for rectal cancer and reporting short-term clinical outcomes. Articles published in English from January 1, 1995 to June, 30 2016 that met the selection criteria were retrieved and reviewed. The Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) statements checklist for reporting a systematic review was followed. Random-effect models were used to estimate mean differences and risk ratios. The robustness and heterogeneity of the results were explored by performing sensitivity analyses. The pooled effect was considered significant when P < 0.05.

RESULTS

Overall, 14 RCTs were included. No differences were found in postoperative mortality (P = 0.19) and morbidity (P = 0.75) rates. The mean operative time was 36.67 min longer (95%CI: 27.22-46.11, P < 0.00001), the mean estimated blood loss was 88.80 ml lower (95%CI: -117.25 to -60.34, P < 0.00001), and the mean incision length was 11.17 cm smaller (95%CI: -13.88 to -8.47, P < 0.00001) for LRR than ORR. These results were confirmed by sensitivity analyses that focused on the four major RCTs. The mean length of hospital stay was 1.71 d shorter (95%CI: -2.84 to -0.58, P < 0.003) for LRR than ORR. Similarly, bowel recovery (i.e., day of the first bowel movement) was 0.68 d shorter (95%CI: -1.00 to -0.36, P < 0.00001) for LRR. The sensitivity analysis did not confirm a significant difference between LRR and ORR for these latter two parameters. The overall quality of the evidence was rated as high.

CONCLUSION

LRR is associated with lesser blood loss, smaller incision length, and longer operative times compared to ORR. No differences are observed for postoperative morbidity and mortality.

Laparoscopic Lavage in the Management of Perforated Diverticulitis: a Contemporary Meta-analysis

IMPORTANCE

Perforated diverticulitis carries the risk of significant comorbidity and mortality. Although colon resection provides adequate source control, the procedure itself carries morbidity, as well as later stoma reversal procedures. The effectiveness of laparoscopic lavage to treat perforated diverticulitis remains unclear.

OBJECTIVE

We aimed to conduct a meta-analysis to evaluate current studies comparing laparoscopic lavage with colon resection in cases of perforated diverticulitis for the effectiveness in source control, without the need for subsequent interventions, stoma formation, and death.

DATA SOURCES

Electronic database searches were conducted using EMBASE, Pubmed, CINAHL, Cochrane databases, and clinicaltrials.gov following PRISMA guidelines.

STUDY SELECTION

Randomized controlled trials (RCTs) were included that compared laparoscopic lavage against colon resection for perforated diverticulitis.

DATA EXTRACTION AND SYNTHESIS

Risk of bias in RCT's was assessed the Cochrane Assessment of Bias risk tool and Jadad scale. A meta-analysis was performed using random-effects risk ratios (RR) and 95% confidence intervals (CI).

MAIN OUTCOME

Outcome measures included the total rate of reoperation, rate of reoperation for infection, need for subsequent percutaneous drainage, stoma formation, and mortality rate within 90 days.

RESULTS

Three eligible randomized controlled studies were identified, with a combined total of 372 patients. Laparoscopic lavage carried an increased rate of total reoperations (RR 2.07; CI 1.12-3.84; p = 0.021) and an increased rate of reoperation for infection (RR 5.56; CI 1.97-15.69; p = 0.001) compared with colon resection. In addition, laparoscopic lavage increased the rate of subsequent percutaneous drainage (RR 6.54; CI 1.77-24.16; p = 0.005) compared with colon resection, but a lesser risk of stoma formation within 90 days (RR 0.18; CI 0.12-0.27; p < 0.001). No difference in mortality rate was observed between treatments (RR 1.03; CI 0.45-2.34; p = 0.950).

CONCLUSION

Despite decreased rates of stoma formation and equivalent mortality rates as compared with colon resection, laparoscopic lavage for Hinchey III diverticulitis fails to completely control the source of infection. Our data show that laparoscopic lavage is associated with increased rates of total reoperations, increased rates of reoperation for infections, and need for subsequent percutaneous drainage.

Comparison of Urinary Tract Infection Rates Associated with Transurethral Catheterization, Suprapubic Tube and Clean Intermittent Catheterization in the Postoperative Setting: A Network Meta-Analysis

PURPOSE

We performed a network meta-analysis of available randomized, controlled trials to elucidate the risks of urinary tract infection associated with transurethral catheterization, suprapubic tubes and intermittent catheterization in the postoperative setting.

MATERIALS AND METHODS

PubMed®, EMBASE® and Google Scholar™ searches were performed for eligible randomized, controlled trials from January 1980 to July 2015 that included patients who underwent transurethral catheterization, suprapubic tube placement or intermittent catheterization at the time of surgery and catheterization lasting up to postoperative day 30. The primary outcome of comparison was the urinary tract infection rate via a network meta-analysis with random effects model using the netmeta package in R 3.2 (www.r-project.org/).

RESULTS

Included in analysis were 14 randomized, controlled trials in a total of 1,391 patients. Intermittent catheterization and suprapubic tubes showed no evidence of decreased urinary tract infection rates compared to transurethral catheterization. Suprapubic tubes and intermittent catheterization had comparable urinary tract infection rates (OR 0.903, 95% CI 0.479-2.555). On subgroup analysis of 10 randomized, controlled trials with available mean catheterization duration data in a total of 928 patients intermittent catheterization and suprapubic tube were associated with significantly decreased risk of urinary tract infection compared to transurethral catheterization when catheterization duration was greater than 5 days (OR 0.173, 95% CI 0.073-0.412 and OR 0.142, 95% CI 0.073-0.276, respectively).

CONCLUSIONS

Transurethral catheterization is not associated with an increased urinary tract infection risk compared to suprapubic tubes and intermittent catheterization if catheterization duration is 5 days or less. However, a suprapubic tube or intermittent catheterization is associated with a lower rate of urinary tract infection if longer term catheterization is expected in the postoperative period.

Prevalence and mortality of abdominal compartment syndrome in severely injured patients: A systematic review

BACKGROUND

Abdominal compartment syndrome (ACS) in severely injured patients is associated with high morbidity and mortality. Many efforts have been made to improve outcome of patients with ACS. A treatment algorithm for ACS patients was introduced on January 1, 2005 by the World Society of the Abdominal Compartment Syndrome. The aim of this study was to determine the prevalence and mortality rate of ACS among severely injured patients before and after January 1, 2005 using a systematic literature review.

METHOD

Databases of Embase, Medline (OvidSP), Web of Science, CINAHL, CENTRAL, PubMed publisher, and Google Scholar were searched for terms related to severely injured patients and ACS. Original studies reporting ACS in trauma patients were considered eligible. Data on study design, population, definitions, prevalence, and mortality rates were extracted. Pooled prevalence and mortality of ACS among severely injured patients were calculated for both time periods using inversed variance weighting assuming a random effects model. Tests for heterogeneity were applied.

RESULTS

A total of 80 publications were included. Prevalence of studies that finished enrolling patients before January 1, 2005 ranged from 0.5% to 36.4% and 0.0% to 28.0% in studies after that date. For severely injured patients admitted to the ICU, this range was 0.5% to 1.3% before 2005 and 0% in one publication in the second time period. For patients with visceral injuries, ACS prevalence ranged 1.0% to 20.0%; one study in the second time period reported 11.1%. The prevalence among severely injured patients who underwent trauma laparotomy ranged from 0.9% to 36.4% in the first time period. Two studies after January 1, 2005 reported ACS prevalence of 2.3% and 13.2%, respectively. The mortality rate in both time periods ranged between 0.0% and 100.0%.

CONCLUSION

The overall prevalence of ACS ranged from 0.0% to 36.4%. Future studies are needed to measure the effect of improved trauma care and effectiveness of the World Society of the Abdominal Compartment Syndrome Consensus Statements.

LEVEL OF EVIDENCE

Systematic review/meta-analysis, level III.

Blood-based microRNAs as biomarkers for the diagnosis of colorectal cancer: a systematic review and meta-analysis

Background:

Colorectal cancer (CRC) is common and associated with significant mortality. Current screening methods for CRC lack patient compliance. microRNAs (miRNAs), identified in body fluids, are negative regulators of gene expression and are dysregulated in many cancers, including CRC. This paper summarises studies identifying blood-based miRNAs dysregulated in CRC compared with healthy controls in an attempt to evaluate their use as a screening tool for the diagnosis of CRC.

Methods:

A search of electronic databases (PubMed and EMBASE) and grey literature was performed between January 2002 and April 2016. Studies reporting plasma or serum miRNAs in the diagnosis of CRC compared with healthy controls were selected. Patient demographics, type of patient sample (serum or plasma), method of miRNA detection, type of normalisation, and the number of significantly dysregulated miRNAs identified were recorded. Statistical evaluation of dysregulated miRNAs using sensitivity, specificity, and area under the curve (AUC) was performed.

Results:

Thirty-four studies investigating plasma or serum miRNAs in the diagnosis of CRC were included. A total of 31 miRNAs were found to be either upregulated (n=17) or downregulated (n=14) in CRC cases as compared with controls. Fourteen studies identified panels of ⩾2 dysregulated miRNAs. The highest AUC, 0.943, was identified using a panel of 4 miRNAs with 83.3% sensitivity and 93.1% specificity. Meta-analysis of studies identifying a single dysregulated miRNA in CRC cases compared with controls was performed. Overall sensitivity and specificity of 28 individual miRNAs in the diagnosis of CRC were 76% (95% CI 72%–80%) and 76% (95% CI 72%–80%), respectively, indicating good discriminative ability of miRNAs as biomarkers for CRC. These data did not change with sensitivity analyses.

Conclusions:

Blood-based miRNAs distinguish patients with CRC from healthy controls with high sensitivity and specificity comparable to other common and invasive currently used screening methods for CRC. In future, miRNAs may be used as a relatively non-invasive blood-based marker for detection of CRC.

Current Role of Minimally Invasive Radical Cholecystectomy for Gallbladder Cancer

Background. For Tis and T1a gallbladder cancer (GbC), laparoscopic cholecystectomy can provide similar survival outcomes compared to open cholecystectomy. However, for patients affected by resectable T1b or more advanced GbC, open approach radical cholecystectomy (RC), consisting in gallbladder liver bed resection or segment 4b-5 bisegmentectomy, with locoregional lymphadenectomy, is considered the gold standard while minimally invasive RC (MiRC) is skeptically considered. Aim. To analyze current literature on perioperative and oncologic outcomes of MiRC for patients affected by GbC. Methods. A Medline review of published articles until June 2016 concerning MiRC for GbC was performed. Results. Data relevant for this review were presented in 13 articles, including 152 patients undergoing an attempt of MiRC for GbC. No randomized clinical trial was found. The approach was laparoscopic in 147 patients and robotic in five. Conversion was required in 15 (10%) patients. Postoperative complications rate was 10% with no mortality. Long-term survival outcomes were reported by 11 studies, two of them showing similar oncologic results when comparing MiRC with matched open RC. Conclusions. Although randomized clinical trials are still lacking and only descriptive studies reporting on limited number of patients are available, current literature seems suggesting that when performed at highly specialized centers, MiRC for GbC is safe and feasible and has oncologic outcomes comparable to open RC.

Transthoracic Anastomotic Leak After Esophagectomy: Current Trends

INTRODUCTION

Leaks from intrathoracic esophagogastric anastomosis are thought to be associated with higher rates of morbidity and mortality than leaks from cervical anastomosis. We challenge this assumption and hypothesize that there is no significant difference in mortality based on the location of the esophagogastric anastomosis.

METHODS

A systematic literature search was conducted using PubMed and Embase databases on all studies published from January 2000 to June 2015, comparing transthoracic (TTE) and transhiatal (THE) esophagectomies. Studies using jejunal or colonic interposition were excluded. Outcomes analyzed were leak rate, leak-associated mortality, overall 30-day mortality, and overall morbidity. Meta-analyses were performed using Mantel-Haenszel statistical analyses on studies reporting leak rates of both approaches. Nominal data are presented as frequency and interquartile range (IQR); measures of the association between treatments and outcomes are presented as odds ratio (OR) with 95 % confidence interval.

RESULTS

Twenty-one studies (3 randomized controlled trials) were analyzed comprising of 7167 patients (54 % TTE). TTE approach yields a lower anastomotic leak rate (9.8 %; IQR 6.0-12.2 %) than THE (12 %; IQR 11.6-22.1 %; OR 0.56 [0.34-0.92]), without any significant difference in leak associated mortality (7.1 % TTE vs. 4.6 % THE: OR 1.83 [0.39-8.52]). There was no difference in overall 30-day mortality (3.9 % TTE vs. 4.3 % THE; OR 0.86 [0.66-1.13]) and morbidity (59.0 % TTE vs. 66.6 % THE; OR 0.76 [0.37-1.59]).

DISCUSSION

Based on meta-analysis, TTE is associated with a lower leak rate and does not result in higher morbidity or mortality than THE. The previously assumed higher rate of transthoracic anastomotic leak-associated mortality is overstated, thus supporting surgeon discretion and other factors to influence the choice of thoracic versus cervical anastomosis.

A Systematic Review and Meta-Analysis of the Relationship Between Hospital Volume and the Outcomes of Percutaneous Coronary Intervention

Previous reviews have suggested that hospital volume is inversely related to in-hospital mortality. However, percutaneous coronary intervention (PCI) practices have changed substantially in recent years, and whether this relationship persists remains controversial.A systematic search was performed using PubMed, Embase, and the Cochrane Library to identify studies that describe the effect of hospital volume on the outcomes of PCI. Critical appraisals of the methodological quality and the risk of bias were conducted independently by 2 authors. Fourteen of 96 potentiality relevant articles were included in the analysis. Twelve of the articles described the relationship between hospital volume and mortality and included data regarding odds ratios (ORs); 3 studies described the relationship between hospital volume and long-term survival, and only 1 study included data regarding hazard ratios (HRs). A meta-analysis of postoperative mortality was performed using a random effects model, and the pooled effect estimate was significantly in favor of high volume providers (OR: 0.79; 95% confidence interval [CI], 0.72-0.86; P < 0.001). A systematic review of long-term survival was performed, and a trend toward better long-term survival in high volume hospitals was observed.This meta-analysis only included studies published after 2006 and revealed that postoperative mortality following PCI correlates significantly and inversely with hospital volume. However, the magnitude of the effect of volume on long-term survival is difficult to assess. Additional research is necessary to confirm our findings and to elucidate the mechanism underlying the volume-outcome relationship.

Systematic review and meta-analysis for laparoscopic versus open colon surgery with or without an ERAS programme

BACKGROUND

In recent years, conventional colorectal resection and its aftercare have increasingly become replaced by laparoscopic surgery and enhanced recovery after surgery (ERAS) pathways, respectively.

OBJECTIVE

To ascertain whether combining laparoscopy and ERAS have additional value within colorectal surgery.

METHODS

A systematic review with meta-analysis was performed with two primary research questions; does laparoscopy offer an advantage when all patients receive ERAS perioperative care and does ERAS offer advantages in a laparoscopically operated patient population. All randomised and controlled clinical trials were identified using MEDLINE, EMBASE and Cochrane databases.

RESULTS

Primary search resulted in 319 hits. After inclusion criteria were applied, three RCTs and six CCTs were included in the meta-analysis. For laparoscopically operated patients with/without ERAS, no differences in morbidity were found and postoperative hospital stay favoured ERAS (MD -2.34 [-3.77, -0.91], Z = 3.20, p = 0.001). When comparing laparoscopy and open surgery within ERAS, major morbidity was significantly reduced in the laparoscopic group (OR 0.42 [0.26, 0.66], Z = 3.73, p = 0.006). Other outcome parameters showed no differences. Quality of included studies was considered moderate to poor overall with small sample sizes.

CONCLUSION

When laparoscopy and ERAS are combined, major morbidity and hospital stay are reduced. The reduction in morbidity seems to be due to laparoscopy rather than ERAS, so laparoscopy by itself offers independent advantages beyond ERAS care. Quality of included studies was moderate to poor, so conclusions should be regarded with some reservations.

Management of appendiceal stump in laparoscopic appendectomy--clips or ligature: a systematic review and meta-analysis

BACKGROUND

Appendicular stump closure is a crucial step during laparoscopic appendectomy. Recently, endoclips (ECs) have been described for ligation of the appendicular stump. The objective of this review was to compare outcomes with EC versus endoligature (EL) for appendiceal stump closure during laparoscopic appendectomy.

MATERIALS AND METHODS

A literature search of Medline, Embase, Cochrane Database, and Google Scholar was performed to identify studies comparing use of EL versus EC in laparoscopic appendectomy between January 1992 and September 2013. Reviews of each study were conducted, and data were extracted. The random-effects model was used to combine data, and between-study heterogeneity was assessed.

RESULTS

Seven of the 101 identified studies met the inclusion criteria: four randomized controlled trials and three case controlled series. For the primary outcome of perioperative and postoperative complications, there was no significant difference between the EC versus EL groups. No differences were noted in length of hospital stay. However, a significant reduction in operative time was observed with EC as opposed to EL (standardized mean difference=-0.90, 95% confidence interval=-1.26 to -0.54, P=.001). Moreover, EC procedures were less expensive than EL procedures.

CONCLUSIONS

EC application in the management of appendiceal stump during laparoscopic appendectomy appears to be simple, efficacious, safe, and a cost-effective alternative.

No decreased infection rate when using antibiotic-impregnated cement in primary total joint arthroplasty

There has been much debate and controversy about the routine use of antibiotic-impregnated bone cement in primary total joint arthroplasty. The purpose of this study was to undertake a meta-analysis to determine whether the use of antibiotic-impregnated bone cement would reduce the incidence of infection after primary total joint arthroplasty. Of 313 citations identified for screening, 6 trials reporting 26,791 patients were eligible for data extraction and meta-analysis. The authors found no statistically significant difference between antibiotic-impregnated bone cement and plain bone cement in terms of the incidence of infection. The results indicated that the use of antibiotic-impregnated bone cement in primary total joint arthroplasty did not lead to a decrease in the rate of infection.

Effect of Using a Safety Checklist on Patient Complications after Surgery

Background:

Previous before-and-after studies indicate that the use of safety checklists in surgery reduces complication rates in patients.

Methods:

A systematic review of studies was undertaken using MEDLINE, CINAHL, Proquest, and the Cochrane Library to identify studies that evaluated the effects of checklist use in surgery on complication rates. Study quality was assessed using the Methodological Index for Nonrandomized Studies. The pooled risk ratio (RR) was estimated using both fixed and random effects models. For each outcome, the number needed to treat (NNT) and the absolute risk reduction (ARR) were also computed.

Results:

Of the 207 intervention studies identified, 7 representing 37,339 patients were included in meta-analyses, and all were cohort studies. Results indicated that the use of checklists in surgery compared with standard practice led to a reduction in any complication (RR, 0.63; 95% CI, 0.58 to 0.72; P &lt; 0.0001; ARR, 3.7%; NNT, 27) and wound infection (RR, 0.54; 95% CI, 0.40 to 0.72; P = 0.0001; ARR, 2.9%; NNT, 34) and also reduction in blood loss (RR, 0.56; 95% CI, 0.45 to 0.70; P = 0.0001; ARR, 3.8%; NNT, 33). There were no significant reductions in mortality (RR, 0.79; 95% CI, 0.57 to 1.11; P = 0.191; ARR, 0.44%; NNT, 229), pneumonia (RR, 1.03; 95% CI, 0.73 to 1.4; P = 0.857; ARR, 0.04%; NNT, 2,512), or unplanned return to operating room (RR, 0.75; 95% CI, 0.56 to 1.02; P = 0.068; ARR, 0.52%; NNT, 192).

Conclusion:

Notwithstanding the lack of randomized controlled trials, synthesis of the existing body of evidence suggests a relationship between checklist use in surgery and fewer postoperative complications.

Surgical technique in distal pancreatectomy: a systematic review of randomized trials

Despite recent improvements in surgical technique, the morbidity of distal pancreatectomy remains high, with pancreatic fistula being the most significant postoperative complication. A systematic review of randomized controlled trials (RCTs) dealing with surgical techniques in distal pancreatectomy was carried out to summarize up-to-date knowledge on this topic. The Cochrane Central Registry of Controlled Trials, Embase, Web of Science, and Pubmed were searched for relevant articles published from 1990 to December 2013. Ten RCTs were identified and included in the systematic review, with a total of 1286 patients being randomized (samples ranging from 41 to 450). The reviewers were in agreement for application of the eligibility criteria for study selection. It was not possible to carry out meta-analysis of these studies because of the heterogeneity of surgical techniques and approaches, such as varying methods of pancreas transection, reinforcement of the stump with seromuscular patch or pancreaticoenteric anastomosis, sealing with fibrin sealants and pancreatic stent placement. Management of the pancreatic remnant after distal pancreatectomy is still a matter of debate. The results of this systematic review are possibly biased by methodological problems in some of the included studies. New well designed and carefully conducted RCTs must be performed to establish the optimal strategy for pancreatic remnant management after distal pancreatectomy.

Systematic review and meta-analysis of the association between diabetes mellitus and incidence and mortality in breast and colorectal cancer

BACKGROUND

Increasing evidence suggests that diabetes mellitus (DM) is associated with increased cancer incidence and mortality. Several mechanisms involved in diabetes, such as promotion of cell proliferation and decreased apoptosis, may foster carcinogenesis. This study investigated the association between DM and cancer incidence and cancer-specific mortality in patients with breast and colorectal carcinoma.

METHODS

A meta-analysis of controlled trials, prospective cohort studies and pooled cohort studies published after 2007 was conducted. Embase, PubMed and the Cochrane Library were searched. Summary hazard ratios (HRs) were calculated using a random-effects model. Sensitivity and subgroup analyses were performed to adjust for confounders, mode of DM assessment and follow-up time.

RESULTS

Twenty studies were included to investigate the association between DM and breast and colorectal cancer incidence and cancer-specific mortality. The studies predominantly comprised patients with type II DM. The overall HR for breast cancer incidence was 1·23 (95 per cent confidence interval 1·12 to 1·34) and that for colorectal cancer was 1·26 (1·14 to 1·40) in patients with DM compared with those without diabetes. The overall HR was 1·38 (1·20 to 1·58) for breast cancer- and 1·30 (1·15 to 1·47) for colorectal cancer-specific mortality in patients with DM compared with those without diabetes.

CONCLUSION

This meta-analysis indicated that DM is a risk factor for breast and colorectal cancer, and for cancer-specific mortality.

The volume effect in liver surgery--a systematic review and meta-analysis

BACKGROUND

There is an inverse relationship between hospital and surgeon volume and mortality in many types of complex surgery. The aim of this paper is to investigate the volume effect on outcomes of liver surgery.

METHODS

A systematic review and meta-analysis was performed. A literature search was conducted using Medline and EMBASE from 1995 to 2012. A random effects model was used.

RESULTS

Seventeen studies were selected for detailed analysis. Definition of a high-volume institution varied from 2 to more than 33 procedures per year. The pooled odds ratio of mortality rate in low- vs high-volume centres was 2.0 [95 % confidence interval (CI), 1.6-2.4; P < 0.001]. Some studies divided centres into more than two groups and compared the highest and lowest volume groups. The pooled odds ratio of mortality rate for this comparison type was 3.2 (95 % CI, 1.7-5.8; P < 0.001). Funnel plots suggest possible publication bias. There was inadequate data to compare morbidity. Only two of seven studies demonstrated a shorter length of stay in the high-volume centres. There was no convincing volume effect on long-term survival.

CONCLUSIONS

This study suggests a strong relationship between volume and perioperative mortality. No difference in morbidity, length of stay or survival was demonstrated.

Simultaneous laparoscopic resection of primary colorectal cancer and associated liver metastases: a systematic review

As many as 25 % of colorectal cancer (CRC) patients have liver metastases at presentation. However, the optimal strategy for resectable synchronous colorectal liver metastasis remains controversial. Despite the increasing use of laparoscopy in colorectal and liver resections, combined laparoscopic resection of the primary CRC and synchronous liver metastasis is rarely performed. The potential benefits of this approach are the possibility to perform a radical operation with small incisions, earlier recovery, and reduction in costs. The aim of this study was to review the literature on feasibility and short-term results of simultaneous laparoscopic resection. We conducted a systematic search of all articles published until February 2013. Search terms included: hepatectomy [Mesh], "liver resection," laparoscopy [Mesh], hand-assisted laparoscopy [Mesh], surgical procedures, minimally invasive [Mesh], colectomy [Mesh], colorectal neoplasms [Mesh], and "colorectal resections." No randomized trials are available. All data have been reported as case reports, case series, or case-control studies. Thirty-nine minimally invasive simultaneous resections were identified in 14 different articles. There were 9 (23 %) major hepatic resections. The most performed liver resection was left lateral sectionectomy in 26 (67 %) patients. Colorectal resections included low rectal resections with total mesorectal excision, right and left hemicolectomies, and anterior resections. Despite the lack of high-quality evidence, the laparoscopic combined procedure appeared to be feasible and safe, even with major hepatectomies. Good patient selection and refined surgical technique are the keys to successful simultaneous resection. Simultaneous left lateral sectionectomy associated with colorectal resection should be routinely proposed.

The effect of NOD2 polymorphism on postsurgical recurrence in Crohn's disease: a systematic review and meta-analysis of available literature

BACKGROUND

Up to 70% of patients requiring surgery for Crohn's disease (CD) develop recurrence within 10 years. Unequivocal markers predicting recurrence are needed to tailor postoperative therapy appropriately. NOD2 (nucleotide-binding oligomerization domain 2) polymorphisms increase the risk of developing CD; however, their ability to predict recurrence is uncertain. This study aims to determine the association between NOD2 variants and surgical recurrence after initial disease-modifying surgery.

METHODS

A comprehensive search for published series comparing the effect of NOD2 polymorphisms on postoperative surgical recurrence in patients with CD was performed. Random-effects methods were used to combine data.

RESULTS

Six cohort studies comprising 1003 patients with CD were included. A total of 340 patients (33.9%) expressed at least 1 of the 3 common NOD2 polymorphisms. The 1003 patients underwent surgical resection with 335 (33%) developing surgical recurrence. Of 340 NOD2-expressing patients, 130 (39%) required further resection, whereas 202 of 663 patients (30.5%) without the variant underwent repeat resection. NOD2 was not significantly associated with surgical recurrence (odds ratio: 1.58, 95% confidence interval: 0.97-2.57, P = 0.064), most likely because of study heterogeneity (Cochran Q: 12.36, P = 0.030, I: 59.6%). The sensitivity of any mutation in predicting disease recurrence was 39.7% and specificity was 69%, with the area under the receiver operating characteristic curve being 0.64.

CONCLUSIONS

Patients with CD with a NOD2 polymorphism do not have an increased risk of surgical recurrence compared with patients without the variant. These data provide insufficient evidence to support postoperative medical prophylaxis based solely on the presence of NOD2 polymorphism.

Roux-en-Y gastric bypass for morbid obesity: what are the preoperative predictors of weight loss?

Obesity has become an increasingly important health problem over the past 30 years. Presently around a quarter of the UK adult population are obese and this figure is set to increase further in the coming decades. The health consequences of obesity on multiple body systems have been well established as has the financial cost of the condition to both the individuals affected as well as to society as a whole. Bariatric surgery has been shown to be the only long term effective solution in terms of sustained weight loss and comorbidity resolution. The commonest bariatric procedure in the UK is the Roux-en-y gastric bypass which consistently results in the loss of 70%-80% of excess bodyweight. Results however are variable and in order to optimise resource allocation and avoid exposing patients unlikely to benefit from surgery to its inherent risks, much research has been done to try to identify those patients most likely to obtain a good result. The only factor which has been subjected to meta-analysis is that of preoperative weight loss which shows a positive association with postoperative weight loss following bypass surgery. Although the remaining data are not based on level 1 evidence those other preoperatively identifiable factors which are associated with an improved outcome include Caucasian or Hispanic ethnicity, higher educational status, non-shift-work working patterns, female gender and divorced or single marital status. Similarly increased levels of preoperative physical activity and an absence of binge eating behaviour are consistent with a favourable result whereas increased age, smoking and other socioeconomic factors have not been shown to have a significant impact. Conversely diabetes mellitus seems to have a slight negative correlation with postoperative weight loss; however, a history of sexual abuse or psychiatric illness has not been shown to have a lasting influence.

Infliximab versus cyclosporine as rescue therapy in acute severe steroid-refractory ulcerative colitis: a systematic review and meta-analysis

PURPOSE

Acute severe colitis affects 25 % of patients with ulcerative colitis (UC). Up to 30-40 % of these patients are resistant to intensive steroid therapy and therefore require rescue therapy to prevent emergent colectomy. Data comparing rescue therapy using infliximab and cyclosporine are limited and equivocal. This study evaluates the outcomes of UC patients receiving infliximab or cyclosporine as rescue therapy in acute severe steroid-refractory exacerbations.

METHODS

Electronic databases (PubMed, EMBASE, and Cochrane database) were searched for studies directly comparing infliximab and cyclosporine in UC, and references of included studies were screened. Two independent reviewers identified relevant studies and extracted data. Meta-analyses were performed using the random effect model. Outcome measures included 3- and 12-month colectomy rates, adverse drug reactions, and postoperative complications.

RESULTS

Six retrospective cohort studies describing 321 patients met the inclusion criteria. The meta-analysis did not show significant differences between infliximab and cyclosporine in the 3-month colectomy rate (odds ratio (OR) = 0.86, 95 % confidence interval (CI) = 0.31-2.41, p = 0.775), in the 12-month colectomy rate (OR = 0.60, 95 % CI = 0.19-1.89, p = 0.381), in adverse drug reactions (OR = 0.76, 95 % CI = 0.34-1.70, p = 0.508), and in postoperative complications (OR = 1.66, 95 % CI = 0.26-10.50, p = 0.591). Funnel plot revealed no publication bias.

CONCLUSIONS

Infliximab and cyclosporine are comparable when used as rescue therapy in acute severe steroid-refractory UC. Randomized trials are required to further evaluate these agents.

Suprapubic compared with transurethral bladder catheterization for gynecologic surgery: a systematic review and meta-analysis

OBJECTIVE

Suprapubic catheterization is commonly used for postoperative bladder drainage after gynecologic procedures. However, recent studies have suggested an increased rate of complications compared with urethral catheterization. We undertook a systematic review and meta-analysis of randomized controlled trials comparing suprapubic catheterization and urethral catheterization in gynecologic populations.

DATA SOURCES

PubMed, EMBASE, CINAHL, Google Scholar, and trial registries were searched from 1966 to March 2012 for eligible randomized controlled trials comparing postoperative suprapubic catheterization and urethral catheterization in gynecologic patients. We used these search terms: "catheter," "supra(-)pubic catheter," "urinary catheter," "gyn(a)ecological," "catheterization techniques gyn(a)ecological surgery," "transurethral catheter," and "bladder drainage." No language restrictions were applied. METHODS AND STUDY SELECTION: The primary outcome was urinary tract infection. Secondary outcomes were the need for recatheterization, duration of catheterization, catheter-related complications, and duration of hospital stay. Pooled effect size estimates were calculated using the random effects model from DerSimonian and Laird.

TABULATION, INTEGRATION, AND RESULTS

In total, 12 eligible randomized controlled trials were included in the analysis (N=1,300 patients). Suprapubic catheterization was associated with a significant reduction in postoperative urinary tract infections (20% compared with 31%, pooled odds ratio [OR] 0.31, 95% confidence interval [CI] 0.185-0.512, P<.01) but an increased risk of complications (29% compared with 11%, pooled OR 4.14, 95% CI 1.327-12.9, P=.01). Complications were mostly related to catheter tube malfunction with no visceral injuries reported. No differences in the rate of recatheterization or hospital stay were demonstrated. Robust patient satisfaction and cost-effectiveness data are lacking.

CONCLUSION

Based on the best available evidence, no route for bladder drainage in gynecologic patients is clearly superior. The reduced rate of infective morbidity with suprapubic catheterization is offset by a higher rate of catheter-related complications and crucially does not translate into reduced hospital stay. As yet, there are insufficient data to determine which route is most appropriate for catheterization; therefore, cost and patient-specific factors should be paramount in the decision. Minimally invasive surgery may alter the requirement for prolonged postoperative catheterization.

The forgotten role of alcohol: a systematic review and meta-analysis of the clinical efficacy and perceived role of chlorhexidine in skin antisepsis

Background

Skin antisepsis is a simple and effective measure to prevent infections. The efficacy of chlorhexidine is actively discussed in the literature on skin antisepsis. However, study outcomes due to chlorhexidine-alcohol combinations are often attributed to chlorhexidine alone. Thus, we sought to review the efficacy of chlorhexidine for skin antisepsis and the extent of a possible misinterpretation of evidence.

Methods

We performed a systematic literature review of clinical trials and systematic reviews investigating chlorhexidine compounds for blood culture collection, vascular catheter insertion and surgical skin preparation. We searched PubMed, CINAHL, the Cochrane Library, the Agency for Healthcare Research and Quality website, several clinical trials registries and a manufacturer website. We extracted data on study design, antiseptic composition, and the following outcomes: blood culture contamination, catheter colonisation, catheter-related bloodstream infection and surgical site infection. We conducted meta-analyses of the clinical efficacy of chlorhexidine compounds and reviewed the appropriateness of the authors′ attribution.

Results

In all three application areas and for all outcomes, we found good evidence favouring chlorhexidine-alcohol over aqueous competitors, but not over competitors combined with alcohols. For blood cultures and surgery, we found no evidence supporting chlorhexidine alone. For catheters, we found evidence in support of chlorhexidine alone for preventing catheter colonisation, but not for preventing bloodstream infection. A range of 29 to 43% of articles attributed outcomes solely to chlorhexidine when the combination with alcohol was in fact used. Articles with ambiguous attribution were common (8–35%). Unsubstantiated recommendations for chlorhexidine alone instead of chlorhexidine-alcohol were identified in several practice recommendations and evidence-based guidelines.

Conclusions

Perceived efficacy of chlorhexidine is often in fact based on evidence for the efficacy of the chlorhexidine-alcohol combination. The role of alcohol has frequently been overlooked in evidence assessments. This has broader implications for knowledge translation as well as potential implications for patient safety.

Surgical techniques for parastomal hernia repair: a systematic review of the literature

BACKGROUND

Parastomal hernias are a frequent complication of enterostomies that require surgical treatment in approximately half of patients. This systematic review aimed to evaluate and compare the safety and effectiveness of the surgical techniques available for parastomal hernia repair.

METHODS

Systematic review was performed in accordance with PRISMA. Assessment of methodological quality and selection of studies of parastomal hernia repair was done with a modified MINORS. Subgroups were formed for each surgical technique. Primary outcome was recurrence after at least 1-year follow-up. Secondary outcomes were mortality and postoperative morbidity. Outcomes were analyzed using weighted pooled proportions and logistic regression.

RESULTS

Thirty studies were included with the majority retrospective. Suture repair resulted in a significantly increased recurrence rate when compared with mesh repair (odds ratio [OR] 8.9, 95% confidence interval [CI] 5.2-15.1; P < 0.0001). Recurrence rates for mesh repair ranged from 6.9% to 17% and did not differ significantly. In the laparoscopic repair group, the Sugarbaker technique had less recurrences than the keyhole technique (OR 2.3, 95% CI 1.2-4.6; P = 0.016). Morbidity did not differ between techniques. The overall rate of mesh infections was low (3%, 95% CI 2) and comparable for each type of mesh repair.

CONCLUSIONS

Suture repair of parastomal hernia should be abandoned because of increased recurrence rates. The use of mesh in parastomal hernia repair significantly reduces recurrence rates and is safe with a low overall rate of mesh infection. In laparoscopic repair, the Sugarbaker technique is superior over the keyhole technique showing fewer recurrences.

Robotic assistance may reduce conversion to open in rectal carcinoma laparoscopic surgery: systematic review and meta-analysis

BACKGROUND

We hypothesized that robotic assistance (RARS) could provide better intraoperative and short-term outcomes than a traditional laparoscopic approach (LARS) to rectal cancer surgery.

METHODS

Systematic review of the literature, including electronic searches and communications to international robotic meetings.

INCLUSION CRITERIA

studies involving rectal cancer patients and comparing outcomes of robotic surgery vs laparoscopic surgery. Primary end-points: conversion and postoperative short-term complications. Meta-analysis performed using Review Manager 5.0 software.

RESULTS

Five case-control studies involving 486 patients (203 RARS-283 LARS) were finally included. Conversion to open rate (RR = 0.31; 95% CI 0.12,0.78) was lower for RARS. No differences were found in oncological outcomes, hospital stay or anastomotic leakage.

CONCLUSIONS

This meta-analysis of available non-randomized studies suggests that conversion to open rate may be reduced when using RARS instead of LARS for rectal cancer.

Minimally invasive video-assisted versus conventional open thyroidectomy: a systematic review of available data

PURPOSE

Minimally invasive video-assisted thyroidectomy (MIVAT) is now emerging as a novel and less invasive procedure for thyroid diseases. This study conducted a systematic review of the available data to evaluate the safety and efficacy of this new technique over conventional procedure.

METHODS

A systematic literature search was performed on Medline, Embase, and The Cochrane Library. Randomized controlled trials comparing the MIVAT with open thyroidectomy were selected and meta-analyzed.

RESULTS

Nine RCTs involving 730 patients were included and all were restricted to patients with a thyroid nodule no larger than 4 cm and surgery did not involve lymph node dissection. Both procedures were of similar efficacy in nodule resection. Open surgery had a 1.6 times higher rate of postoperative complications than the novel technique, with no significant difference (P = 0.08), especially in transient recurrent nerve palsy (OR = 0.93, P = 0.87). Although longer operative time was required for MIVAT (MD = 15.0 min, P < 0.00001), patients experienced less postoperative pain, especially in the early postoperative period (MD = -11.52, P = 0.0003). There was also a shorter incision length (MD = -2.36 cm, P < 0.00001), better cosmetic results and greater patient satisfaction in the novel technique group (WD = 2.59; P < 0.00001).

CONCLUSIONS

MIVAT is a feasible, practical, and safe alternative with better cosmetic benefits, and it can be performed with an ease of manipulation that is similar to that of conventional neck surgery.