Low-fat/high-fibre diet prehabilitation improves anastomotic healing via the microbiome: an experimental model

Comparison of two bundles for reducing surgical site infection in colorectal surgery: multicentre cohort study

BACKGROUND

There is controversy regarding the maximum number of elements that can be included in a surgical site infection prevention bundle. In addition, it is unclear whether a bundle of this type can be implemented at a multicentre level.

METHODS

A pragmatic, multicentre cohort study was designed to analyse surgical site infection rates in elective colorectal surgery after the sequential implementation of two preventive bundle protocols. Secondary outcomes were to determine compliance with individual measures and to establish their effectiveness, duration of stay, microbiology and 30-day mortality rate.

RESULTS

A total of 32 205 patients were included. A 50% reduction in surgical site infection was achieved after the implementation of two sequential sets of bundles: from 18.16% in the Baseline group to 10.03% with Bundle-1 and 8.19% with Bundle-2. Bundle-2 reduced superficial-surgical site infection (OR 0.74 (95% c.i. 0.58 to 0.95); P = 0.018) and deep-surgical site infection (OR 0.66 (95% c.i. 0.46 to 0.93); P = 0.018) but not organ/space-surgical site infection (OR 0.88 (95% c.i. 0.74 to 1.06); P = 0.172). Compliance increased after the addition of four measures to Bundle-2. In the multivariable analysis, for organ/space-surgical site infection, laparoscopy, oral antibiotic prophylaxis and mechanical bowel preparation were protective factors in colonic procedures, while no protective factors were found in rectal surgery. Duration of stay fell significantly over time, from 7 in the Baseline group to 6 and 5 days for Bundle-1 and Bundle-2 respectively (P < 0.001). The mortality rate fell from 1.4% in the Baseline group to 0.59% and 0.6% for Bundle-1 and Bundle-2 respectively (P < 0.001). There was an increase in Gram-positive bacteria and yeast isolation, and reduction in Gram-negative bacteria and anaerobes in organ/space-surgical site infection.

CONCLUSIONS

The addition of measures to create a final 10-measure protocol had a cumulative protective effect on reducing surgical site infection. However, organ/space-surgical site infection did not benefit from the addition. No protective measures were found for organ/space-surgical site infection in rectal surgery. Compliance with preventive measures increased from Bundle-1 to Bundle-2.

Social determinants of health, the microbiome, and surgical injury

ABSTRACT

Postinjury infection continues to plague trauma and emergency surgery patients fortunate enough to survive the initial injury. Rapid response systems, massive transfusion protocols, and the development of level 1 trauma centers, among others, have improved the outcome for millions of patients worldwide. Nonetheless, despite this excellent initial care, patients still remain vulnerable to postinjury infections that can result in organ failure, prolonged critical illness, and even death. While risk factors have been identified (degree of injury, blood loss, time to definitive care, immunocompromise, etc.), they remain probabilistic, not deterministic, and do not explain outcome variability at the individual case level. Here, we assert that analysis of the social determinants of health, as reflected in the patient's microbiome composition (i.e., community structure, membership) and function (metabolomic output), may offer a "window" with which to define individual variability following traumatic injury. Given emerging knowledge in the field, a more comprehensive evaluation of biomarkers within the patient's microbiome, from stool-based microbial metabolites to those in plasma and those present in exhaled breath, when coupled with clinical metadata and machine learning, could lead to a more deterministic assessment of an individual's risk for a poor outcome and those factors that are modifiable. The aim of this piece is to examine how measurable elements of the social determinants of health and the life history of the patient may be buried within the ecologic memory of the gut microbiome. Here we posit that interrogation of the gut microbiome in this manner may be used to inform novel approaches to drive recovery following a surgical injury.

A review of perioperative immune-modulating and metabolic-modulating nutrition strategies for bowel resection surgery

Focused perioperative nutrition strategies have proven benefits on the outcomes for patients undergoing major abdominal surgery. In this brief article, we will review these strategies and the evidence to support them with a focus on gastrointestinal anastomotic healing. We will elaborate the risks and benefits of enteral feeds, immune- and metabolic-modulating formulas, prebiotics and probiotics, and prehabilitation in preparation for surgery. Additionally, we will discuss the role of fish oils (eicosapentaenoic acid and docosahexaenoic acid) in the surgical patient and new data on specialized proresolving mediators in inflammation resolution. Finally, this article will consider the harmful impact surgical trauma has on the microbiome and the potential for perioperative dietary modulation to attenuate these negative effects.

Colorectal Disease and the Gut Microbiome: What a Surgeon Needs to Know

The gut microbiome is defined as the microorganisms that reside within the gastrointestinal tract and produce a variety of metabolites that impact human health. These microbes play an intricate role in human health, and an imbalance in the gut microbiome, termed gut dysbiosis, has been implicated in the development of varying diseases. The purpose of this review is to highlight what is known about the microbiome and its impact on colorectal cancer, inflammatory bowel disease, constipation, Clostridioides difficile infection, the impact of bowel prep, and anastomotic leaks.

Effects of diet and antibiotics on anastomotic healing: A mouse model study with varied dietary fiber and fat, and pre-operative antibiotics

INTRODUCTION

This study investigated the separate impacts of diet and pre-operative antibiotics on gut microbiome and colonic anastomotic healing using a mouse model.

METHODS

Male C57BL/6J mice were fed either low-fat-high-fibre (SD) or high-fat-low-fiber (WD) groups for 6 weeks, then further received either pre-operative antibiotics or a control sham before a colonic anastomotic procedure was performed. After 7 days, the anastomosis was assessed and microbiota composition and biodiversity were analyzed in anastomotic tissue and stool.

RESULTS

WD-fed mice had shorter survival (5.2 ​± ​2.3 vs. 6.9 ​± ​2.3 days, p ​= ​0.022), increased weight loss (5.55 ​± ​3.80g vs. 2.65 ​± ​2.36g, p ​= ​0.03), and reduced biodiversity compared to SD-fed mice. Pre-operative antibiotics improved anastomotic healing scores (1.33 ​± ​0.65 vs. 2.08 ​± ​0.79, p ​= ​0.02) and reduced Enterococcus faecalis growth in tissue and stool (p ​= ​0.02, p ​= ​0.02). Improved anastomotic healing correlated with lower Enterococcus abundance (p ​= ​0.04) and higher collagen III and IV levels (p ​= ​0.01, 0.04) in anastomotic tissue.

CONCLUSION

SD promotes enhanced post-operative recovery and increased microbiome biodiversity, while pre-operative antibiotics enhance anastomotic healing by suppressing Enterococcus faecalis growth, mitigating collagen III/IV degradation.

Effects of Habitual Dietary Change on the Gut Microbiota and Health of Silkworms

Diet plays a crucial role in shaping the gut microbiota and overall health of animals. Traditionally, silkworms are fed fresh mulberry leaves, and artificial diets do not support good health. The aim of this study was to explore the relationship between the dietary transition from artificial diets to mulberry leaves and the effects on the gut microbiota and physiological changes in silkworms as a model organism. With the transition from artificial diets to mulberry leaves, the diversity of the silkworm gut microbiota increased, and the proportion of Enterococcus and Weissella, the dominant gut bacterial species in silkworms reared on artificial diets, decreased, whereas the abundance of Achromobacter and Rhodococcus increased. Dietary transition at different times, including the third or fifth instar larval stages, resulted in significant differences in the growth and development, immune resistance, and silk production capacity of silkworms. These changes might have been associated with the rapid adaptation of the intestinal microbiota of silkworms to dietary transition. This study preliminarily established a dietary transition-gut microbial model in silkworms based on the conversion from artificial diets to mulberry leaves, thus providing an important reference for future studies on the mechanisms through which habitual dietary changes affect host physiology through the gut microbiome.

Systematic review of the significance of neutrophil to lymphocyte ratio in anastomotic leak after gastrointestinal surgeries

INTRODUCTION

The inflammatory response is thought to be a critical initiator of epigenetic alterations. The neutrophil to lymphocyte ratio (NLR), a biomarker of inflammation, is computed by dividing the number of neutrophils by the number of lymphocytes. The primary goal of this systematic review and meta-analysis was to evaluate the pre-operative NLR of gastrointestinal surgery patients who had an anastomotic leak (AL) in comparison to those who did not AL.

METHODS

We performed a comprehensive search for relevant papers published before May 4, 2022, using PubMed, Scopus, and Web of Science. Standardized mean difference (SMD) with a 95% confidence interval (CI) was pooled in meta-analysis to yield a summary estimate. We utilized the random-effects model to create pooled effects since we discovered a substantial heterogeneity level. For evaluating quality, the Newcastle-Ottawa scale (NOS) was implemented.

RESULTS

The research comprised 12 studies with a total of 2940 individuals who had GI operations, 353 of whom went on to develop AL. We discovered that patients who had GI surgeries and acquired AL had significantly higher NLR levels than those who did not (random-effects model: SMD = 0.75, 95% CI = 0.11-1.38, p = 0.02). Patients with AL showed significantly higher NLR levels than control group in retrospective studies (SMD = 0.93, 95% CI = 0.20-1.66, p=0.01) but not in prospective studies (SMD = - 0.11, 95% CI = - 0.65-0.43, p = 0.69), according to the subgroup analysis based on research design. Subgroup analysis based on ethnicity yielded that white patients with AL exhibited significantly higher NLR values than the control group (SMD = 1.35, 95% CI = 0.01-2.68, p = 0.04) but this result was not applied to East Asian patients (SMD = 0.14, 95% CI = -0.13-0.41, p = 0.29).

CONCLUSION

Our research suggests a potential association between preoperative NLR and postoperative AL. However, it is essential to acknowledge the variability in the findings, with significantly higher NLR levels observed in retrospective studies and among white patients, but not consistently replicated in prospective studies and among East Asian patients. Further investigations with larger and more diverse cohorts are warranted to validate these findings and explore potential factors contributing to the observed discrepancies.

Diet-induced shifts in the gut microbiota influence anastomotic healing in a murine model of colonic surgery

Host diet and gut microbiota interact to contribute to perioperative complications, including anastomotic leak (AL). Using a murine surgical model of colonic anastomosis, we investigated how diet and fecal microbial transplantation (FMT) impacted the intestinal microbiota and if a predictive signature for AL could be determined. We hypothesized that a Western diet (WD) would impact gut microbial composition and that the resulting dysbiosis would correlate with increased rates of AL, while FMT from healthy, lean diet (LD) donors would reduce the risk of AL. Furthermore, we predicted that surgical outcomes would allow for the development of a microbial preclinical translational tool to identify AL. Here, we show that AL is associated with a dysbiotic microbial community characterized by increased levels of Bacteroides and Akkermansia. We identified several key taxa that were associated with leak formation, and developed an index based on the ratio of bacteria associated with the absence and presence of leak. We also highlight a modifiable connection between diet, microbiota, and anastomotic healing, potentially paving the way for perioperative modulation by microbiota-targeted therapeutics to reduce AL.

Western Diet-induced Transcriptional Changes in Anastomotic Tissue Is Associated With Early Local Recurrence in a Mouse Model of Colorectal Surgery

OBJECTIVE

To determine the timeframe and associated changes in the microenvironment that promote the development of a diet-induced local-regional recurrence in a mouse model of colorectal surgery.

BACKGROUND

Postoperative recurrence and metastasis occur in up to 30% of patients undergoing attempted resection for colorectal cancer (CRC). The underlying mechanisms that drive the development of postoperative recurrences are poorly understood. Preclinical studies have demonstrated a diet and microbial-driven pathogenesis of local-regional recurrence, yet the precise mechanisms remain undefined.

METHODS

BALB/C mice were fed a western diet (WD) or standard diet (SD), underwent a colon resection and anastomosis, given an Enterococcus faecalis enema on postoperative day (POD) 1, and subjected to a CT26 cancer cell enema (mimicking shed cancer cells) on POD2. Mice were sacrificed between POD3 and POD7 and cancer cell migration was tracked. Dynamic changes in gene expression of anastomotic tissue that were associated with cancer cell migration was assessed.

RESULTS

Tumor cells were identified in mice fed either a SD or WD in both anastomotic and lymphatic tissue as early as on POD3. Histology demonstrated that these tumor cells were viable and replicating. In WD-fed mice, the number of tumor cells increased over the early perioperative period and was significantly higher than in mice fed a SD. Microarray analysis of anastomotic tissue found that WD-fed mice had 11 dysregulated genes associated with tumorigenesis.

CONCLUSIONS

A WD promotes cancer cells to permeate a healing anastomosis and migrate into anastomotic and lymphatic tissue forming viable tumor nodules. These data offer a novel recurrence pathogenesis by which the intestinal microenvironment promotes a CRC local-regional recurrence.

Recommendations on the use of prehabilitation, i.e. comprehensive preparation of the patient for surgery

Prehabilitation is a comprehensive preparation of a patient for primarily surgical treatments. Its aim is to improve the patient'sgeneral condition so as to reduce the risk of complications and ensure the fastest possible recovery to full health. Thebasic components of prehabilitation include: improvement of nutritional status, appropriate exercises to improve functioning,psychological support, and help in eliminating addictions. Other important aspects of prehabilitation are: increasinghemoglobin levels in patients with anemia, achieving good glycemic control in patients with diabetes, treatment or stabilizationof any concurrent disorders, or specialist treatment associated with a specific procedure (endoprostheses, ostomyprocedure). This article organizes and outlines the indications for prehabilitation, its scope, duration, and the method to conductit. Experts of various specialties related to prehabilitation agree that it should be an element of surgery preparationwhenever possible, especially in patients with co-existing medical conditions who have been qualified for major procedures.Prehabilitation should be carried out by interdisciplinary teams, including family physicians and various specialists in thetreatment of comorbidities. Prehabilitation requires urgent systemic and reimbursement solutions.

What Is the Role of the Gut in Wound Infections?

Emerging evidence suggest a major role for the gut microbiome in wound infections. A Trojan Horse mechanism of surgical site infections has been hypothesized to occur when pathogens in the gut, gums, and periodontal areas enter an immune cell and silently travel to the wound site where they release their infectious payload. Genetic tracking of microbes at the strain level is now possible with genetic sequencing techniques and can clarify the origin of microbes that cause wound infections. An emerging field of dietary prehabilitation to modulate the microbiome before surgery is being described to improve infection-related outcomes from surgery.

Mechanobiological considerations in colorectal stapling: Implications for technology development

Technological advancements in minimally invasive surgery have led to significant improvements in patient outcomes. One such technology is surgical stapling, which has evolved into a key component of many operating rooms by facilitating ease and efficacy in resection and repair of diseased or otherwise compromised tissue. Despite such advancements, adverse post-operative outcomes such as anastomotic leak remain a persistent problem in surgical stapling and its correlates (i.e., hand-sewing), most notably in low colorectal or coloanal procedures. Many factors may drive anastomotic leaks, including tissue perfusion, microbiome composition, and patient factors such as pre-existing disease. Surgical intervention induces complex acute and chronic changes to the mechanical environment of the tissue; however, roles of mechanical forces in post-operative healing remain poorly characterized. It is well known that cells sense and respond to their local mechanical environment and that dysfunction of this "mechanosensing" phenomenon contributes to a myriad of diseases. Mechanosensing has been investigated in wound healing contexts such as dermal incisional and excisional wounds and development of pressure ulcers; however, reports investigating roles of mechanical forces in adverse post-operative gastrointestinal wound healing are lacking. To understand this relationship well, it is critical to understand: 1) the intraoperative material responses of tissue to surgical intervention, and 2) the post-operative mechanobiological response of the tissue to surgically imposed forces. In this review, we summarize the state of the field in each of these contexts while highlighting areas of opportunity for discovery and innovation which can positively impact patient outcomes in minimally invasive surgery.

Rationale for Colonic Pre-Habilitation Prior to Restoration of Gastrointestinal Continuity

The emergence of the gut microbiome as a complex ecosystem that plays a key role in human heath and disease has touched virtually every aspect of medical and surgical care. With the advent of next-generation technology to interrogate the microbiome at the level of its membership, community structure and production of metabolites, applying measures by which the gut microbiome can be manipulated to the advantage of both the patient and provider is now possible. Among the many proposed methods, the most practical and promising is dietary pre-habilitation of the gut microbiome prior to high-risk anastomotic surgery. In this review, we will outline the scientific rationale and molecular underpinning that support dietary pre-habilitation as a practical and deliverable method to prevent complications after high-risk anastomotic surgery.

Synbiotics and Surgery: Can Prebiotics and Probiotics Affect Inflammatory Surgical Outcomes?

PURPOSE OF REVIEW

Prebiotics, probiotics, and synbiotics have received increasing attention over the years for their beneficial impact on the gut microbiome and for their systemic anti-inflammatory effects. They have also been shown to improve surgical outcomes. Here, we review the inflammatory effects of surgery as well as the data which suggests a benefit of prebiotics, probiotics, and synbiotics taken in the perioperative period.

RECENT FINDINGS

Synbiotics and fermented foods may have an even greater anti-inflammatory effect than probiotics or prebiotics alone. Recent data suggest that the anti-inflammatory effects and microbiome changes brought on by prebiotics, probiotics, and synbiotics have the potential to improve surgical outcomes. We highlight the potential to alter systemic inflammation, surgical and hospital-acquired infections, colorectal cancer formation, recurrence, and anastomotic leak. Synbiotics could also impact metabolic syndrome. Prebiotics, probiotics, and especially synbiotics may be extremely beneficial when taken in the perioperative period. Even short-term gut microbiome pre-habilitation could alter surgical outcomes significantly.

Novel nutrition strategies to enhance recovery after surgery

Surgery and traumatic injury set off a cascade of metabolic changes that are becoming better understood. Recently, strategies and protocols have been developed for optimizing outcomes, and this has yielded beneficial results. This brief review evaluates three specific nutrition or metabolic interventions in the postoperative setting that attempt to optimize outcomes. We limited this to three subspecialty areas including oncologic surgery, orthopedic surgery, and cardiac surgery. These agents included fish oils, factors to prevent dysbiosis, and resistance exercise and its role in enhancing protein update. Where these novel agents fit into the basic tenets of postoperative nutrition interventions does not change the narrative: deliver graduated early enteral feeding to attenuate the metabolic response to surgical stress, maintain the gastrointestinal mucosal barrier, use immune/metabolic modulation to enhance immune response while attenuating excessive inflammation, and support the microbiome.

Microbiota Phenotype Promotes Anastomotic Leakage in a Model of Rats with Ischemic Colon Resection

Anastomotic leakage (AL) is a major cause of morbidity and mortality after colorectal surgery, but the mechanism behind this complication is still not fully understood. Despite the advances in surgical techniques and perioperative care, the complication rates have remained steady. Recently, it has been suggested that colon microbiota may be involved in the development of complications after colorectal surgery. The aim of this study was to evaluate the association of gut microbiota in the development of colorectal AL and their possible virulence strategies to better understand the phenomenon. Using 16S rRNA sequencing of samples collected on the day of surgery and the sixth day following surgery, we analyzed the changes in tissue-associated microbiota at anastomotic sites created in a model of rats with ischemic colon resection. We discovered a trend for lower microbial diversity in the AL group compared to non-leak anastomosis (NLA). There were no differences in relative abundance in the different types of microbial respiration between these groups and the high abundance of the facultative anaerobic Gemella palaticanis is a marker species that stands out as a distinctive feature.

The Influence of the Microbiome on Anastomotic Leak

Anastomotic leak, defined by the International Study Group of Rectal Cancer as "a communication between the intra- and extraluminal compartments owing to a defect of the integrity of the intestinal wall at the anastomosis," is one of the most devastating complications in colorectal surgery. Much work has been done to identify causes of leak; however, despite advances in surgical technique, the prevalence of anastomotic leak has remained at around 11%. The potential causative role of bacteria in the etiopathology of anastomotic leak was established in the 1950s. More recently, alterations in the colonic microbiome have been shown to affect rates of anastomotic leak. Multiple perioperative factors that alter the homeostasis of the gut microbiota community structure and function have been linked to anastomotic leak after colorectal surgery. Here, we discuss the role of diet, radiation, bowel preparation, medications including nonsteroidal anti-inflammatory drugs, morphine, and antibiotics, and specific microbial pathways that have been implicated in anastomotic leak via their effects on the microbiome.

What Is the Microbiome? A Description of a Social Network

The gut microbiome has coevolved with its hosts over the years, forming a complex and symbiotic relationship. It is formed by what we do, what we eat, where we live, and with whom we live. The microbiome is known to influence our health by training our immune system and providing nutrients for the human body. However, when the microbiome becomes out of balance and dysbiosis occurs, the microorganisms within can cause or contribute to diseases. This major influencer on our health is studied intensively, but it is unfortunately often overlooked by the surgeon and in surgical practice. Because of that, there is not much literature about the microbiome and its influence on surgical patients or procedures. However, there is evidence that it plays a major role, showing that it needs to be a topic of interest for the surgeon. This review is written to show the surgeon the importance of the microbiome and why it should be taken into consideration when preparing or treating patients.

Exploring the roles of intestinal flora in enhanced recovery after surgery

Striving to optimize surgical outcomes, the Enhanced Recovery After Surgery (ERAS) pathway mitigates patients' stress through the implementation of evidence-based practices during the pre-, intra-, and postoperative periods. Intestinal flora is a sophisticated ecosystem integrating with the host and the external environment, which serves as a mediator in diverse interventions of ERAS to regulate human metabolism and inflammation. This review linked gut microbes and their metabolites with ERAS interventions, offering novel high-quality investigative proponents for ERAS. ERAS could alter the composition and function of intestinal flora in patients by alleviating various perioperative stress responses. Modifying gut flora through multiple modalities, such as diet and nutrition, to accelerate recovery might be a complementary approach when exploring novel ERAS initiatives. Meanwhile, the pandemic of COVID-19 and the availability of promising qualitative evidence created both challenges and opportunities for the establishment of ERAS mode.

The implication of gut microbiota in recovery from gastrointestinal surgery

Recovery from gastrointestinal (GI) surgery is often interrupted by the unpredictable occurrence of postoperative complications, including infections, anastomotic leak, GI dysmotility, malabsorption, cancer development, and cancer recurrence, in which the implication of gut microbiota is beginning to emerge. Gut microbiota can be imbalanced before surgery due to the underlying disease and its treatment. The immediate preparations for GI surgery, including fasting, mechanical bowel cleaning, and antibiotic intervention, disrupt gut microbiota. Surgical removal of GI segments also perturbs gut microbiota due to GI tract reconstruction and epithelial barrier destruction. In return, the altered gut microbiota contributes to the occurrence of postoperative complications. Therefore, understanding how to balance the gut microbiota during the perioperative period is important for surgeons. We aim to overview the current knowledge to investigate the role of gut microbiota in recovery from GI surgery, focusing on the crosstalk between gut microbiota and host in the pathogenesis of postoperative complications. A comprehensive understanding of the postoperative response of the GI tract to the altered gut microbiota provides valuable cues for surgeons to preserve the beneficial functions and suppress the adverse effects of gut microbiota, which will help to enhance recovery from GI surgery.

Protection against Metabolic Associated Fatty Liver Disease by Protocatechuic Acid

Gut microbiota-diet interaction has been identified as a key factor of metabolic associated fatty liver disease (MAFLD). Recent studies suggested that dietary polyphenols may protect against MAFLD by regulating gut microbiota; however, the underlying mechanisms remain elusive. We first investigated the effects of cyanidin 3-glucoside and its phenolic metabolites on high-fat diet induced MAFLD in C57BL/6J mice, and protocatechuic acid (PCA) showed a significant positive effect. Next, regulation of PCA on lipid metabolism and gut microbiota were explored by MAFLD mouse model and fecal microbiota transplantation (FMT) experiment. Dietary PCA reduced intraperitoneal and hepatic fat deposition with lower levels of transaminases (AST & ALT) and inflammatory cytokines (IL-1β, IL-2, IL-6, TNF-α & MCP-1), but higher HDL-c/LDL-c ratio. Characterization of gut microbiota indicated that PCA decreased the Firmicutes/Bacteroidetes ratio mainly by reducing the relative abundance of genus Enterococcus, which was positively correlated with the levels of LDL-c, AST, ALT and most of the up-regulated hepatic lipids by lipidomics analysis. FMT experiments showed that Enterococcus faecalis caused hepatic inflammation, fat deposition and insulin resistance with decreased expression of carnitine palmitoyltransferase-1 alpha (CPT1α), which can be reversed by PCA through inhibiting Enterococcus faecalis. Transcriptomics analysis suggested that Enterococcus faecalis caused a significant decrease in the expression of fibroblast growth factor 1 (Fgf1), and PCA recovered the expression of Fgf1 with insulin-like growth factor binding protein 2 (Igfbp2), insulin receptor substrate 1 (Irs1) and insulin receptor substrate 2 (Irs2). These results demonstrated that high proportion of gut Enterococcus faecalis accelerates MAFLD with decreased expression of CPT1α and Fgf1, which can be prevented by dietary supplementation of PCA.

Predictive Role of Neutrophil to Lymphocyte Ratio in Adnexal Torsion: A Systematic Review and Meta-Analysis

Introduction. The goal of this systematic review and meta-analysis was to consolidate the available data on the role of the neutrophil to lymphocyte ratio (NLR) in predicting adnexal torsion (AT), to help guide clinical decision-making and outcomes. Methods. We used Web of Science, PubMed, and Scopus to conduct a systematic search for relevant publications published before June 26, 2022. We reported standardized mean difference (SMD) with a 95% confidence interval (CI). Because a significant level of heterogeneity was found, we used the random-effects model to calculate pooled effects. We used the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) too for quality assessment. Results. Overall, 15 articles were included in the analysis. A random-effects model revealed that patients with AT had elevated levels of NLR compared to those with other adnexal masses ( $\text{SMD}=1.06$ , $95\%\text{CI}=0.67$ to 1.45, $p<0.001$ ). So, NLR had diagnostic value. In the subgroup analysis according to ethnicity, we found that Caucasian patients with AT had elevated levels of NLR compared to patients who were operated due to adnexal mass and reported as having a benign ovarian cyst, without torsion ( $\text{SMD}=1.12$ , $95\%\text{CI}=0.71$ to 1.54, $p<0.001$ ). However, in the case of East Asian patients, there was no difference between cases and controls ( $\text{SMD}=0.86$ , $95\%\text{CI}=-0.21$ to 1.94, $p=0.11$ ). The pooled sensitivity of NLR was 0.79 ( $95\%\text{CI}=0.72–0.85$ ), and the pooled specificity was 0.84 (95% CI, 0.74–0.91). Conclusion. In conclusion, there has been an interest in the use of NLR as a diagnostic marker for AT.

Mucosa and microbiota – the role of intrinsic parameters on intestinal wound healing

Mucosal healing in the gut is an essential process when it comes to chronic inflammatory disorders such as inflammatory bowel diseases (IBD) but also to the creation of intestinal anastomosis. Despite an improvement of surgical techniques, the rates of anastomotic leakage remain substantial and represent a significant health-care and socio-economic burden. Recent research has focused on intrinsic factors such as mucosal linings and differences in the intestinal microbiota and identified specific endoluminal bacteria and epithelial proteins which influence intestinal wound healing and re-establishment of mucosal homeostasis. Despite the lack of large clinical studies, previous data indicate that the identified bacteria such as aerotolerant lactobacilli or wound-associated Akkermansia muciniphila as well as epithelial-expressed sialyl Lewis glycans or CD47 might be critical for wound and anastomotic healing in the gut, thus, providing a potential novel approach for future treatment strategies in colorectal surgery and IBD therapy. Since microbiota and mucosa are interacting closely, we outline the current discoveries about both subsets in this review together to demonstrate the significant interplay

Dietary modulation of gut microbiota in patients with colorectal cancer undergoing surgery: A review

Colorectal cancer (CRC) is the third most frequent malignancy and the second cause of cancer death worldwide. Several factors have been postulated to be involved in CRC pathophysiology, including physical inactivity, unhealthy dietary habits, obesity, and the gut microbiota. Emerging data suggest that the microbiome may play a key role in CRC prognosis and derived complications in patients undergoing colorectal surgery. On the other hand, dietary intervention has been demonstrated to be able to induce significant changes in the gut microbiota and related metabolites in different conditions; therefore, the manipulation of gut microbiota through dietary intervention may constitute a useful approach to improve perioperative dysbiosis and post-surgical outcomes in patients with CRC. In this article, we review the role of the gut microbiota in CRC surgery complications and the potential therapeutic modulation of gut microbiome through nutritional intervention in patients with CRC undergoing surgery.

Perceptions of safety culture and recording in the operating room: understanding barriers to video data capture

OBJECTIVE

Recording in the operating room is an important tool to help surgical teams improve their performance. This is becoming more feasible using the Operating Room Black Box, a comprehensive data capture platform. Operating room (OR) staff, however, may voice reasonable concerns as recording initiatives are implemented. The objective of this study was to assess pre-implementation attitudes of OR staff toward operative recording and explore the relationship of these attitudes to the themes of (1) safety culture, (2) impostor syndrome, and (3) privacy concerns.

METHODS

This cross-sectional survey study measured staff members' beliefs and opinions of operative recording and used three previously validated tools (safety attitudes questionnaire, clance impostor phenomenon scale, and dispositional privacy concern) to assess personal and professional factors. Concepts were correlated using Pearson's correlation coefficient.

RESULTS

Forty-three staff members participated in this study, with a response rate of 45% (n = 43/96, 20/22 nurses, 9/11 gynecologists, 14/63 anesthesiologists). Opinions of operative data capture were generally positive (5-point Likert scale, mean = 3.81, SD = 0.91). Nurses tended to have more favorable opinions of the OR Black Box as compared to gynecologists and anesthesiologists, though this did not reach statistical significance (4.15 vs. 3.67 vs 3.43, p = 0.06). Impostor syndrome characteristics correlated with concerns about litigation related to recording (r =  - 0.32, p = 0.04).

CONCLUSION

There are personal and professional attributes of the OR team that impact perceptions of the OR Black Box and implications around privacy and litigation. Addressing these concerns may facilitate successful implementation of the OR Black Box and improve team communication and patient safety in the OR.

The Problem of Appetite Loss After Major Abdominal Surgery

Objective:

To systematically review the problem of appetite loss after major abdominal surgery.

Summary of Background Data:

Appetite loss is a common problem after major abdominal surgery. Understanding of etiology and treatment options is limited.

Methods:

We searched Medline, Cochrane Central Register of Controlled Trials, and Web of Science for studies describing postoperative appetite loss. Data were extracted to clarify definition, etiology, measurement, surgical influence, pharmacological, and nonpharmacological treatment. PROSPERO registration ID: CRD42021224489.

Results:

Out of 6144 articles, we included 165 studies, 121 of which were also analyzed quantitatively. A total of 19.8% were randomized, controlled trials (n = 24) and 80.2% were nonrandomized studies (n = 97). The studies included 20,506 patients undergoing the following surgeries: esophageal (n = 33 studies), gastric (n = 48), small bowel (n = 6), colon (n = 27), rectal (n = 20), hepatobiliary (n = 6), and pancreatic (n = 13). Appetite was mostly measured with the Quality of Life Questionnaire of the European Organization for Research and Treatment of Cancer (EORTC QLQ C30, n = 54). In a meta-analysis of 4 randomized controlled trials gum chewing reduced time to first hunger by 21.2 hours among patients who had bowel surgery. Other reported treatment options with positive effects on appetite but lower levels of evidence include, among others, intravenous ghrelin administration, the oral Japanese herbal medicine Rikkunshito, oral mosapride citrate, multidisciplin-ary-counseling, and watching cooking shows. No studies investigated the effect of well-known appetite stimulants such as cannabinoids, steroids, or megestrol acetate on surgical patients.

Conclusions:

Appetite loss after major abdominal surgery is common and associated with increased morbidity and reduced quality of life. Recent studies demonstrate the influence of reduced gastric volume and ghrelin secretion, and increased satiety hormone secretion. There are various treatment options available including level IA evidence for postoperative gum chewing. In the future, surgical trials should include the assessment of appetite loss as a relevant outcome measure.

Re-examining chemically defined liquid diets through the lens of the microbiome

Trends in nutritional science are rapidly shifting as information regarding the value of eating unprocessed foods and its salutary effect on the human microbiome emerge. Unravelling the evolution and ecology by which humans have harboured a microbiome that participates in every facet of health and disease is daunting. Most strikingly, the host habitat has sought out naturally occurring foodstuff that can fulfil its own metabolic needs and also the needs of its microbiota, each of which remain inexorably connected to one another. With the introduction of modern medicine and complexities of critical care, came the assumption that the best way to feed a critically ill patient is by delivering fibre-free chemically defined sterile liquid foods (that is, total enteral nutrition). In this Perspective, we uncover the potential flaws in this assumption and discuss how emerging technology in microbiome sciences might inform the best method of feeding malnourished and critically ill patients.

Anastomotic Leak: Toward an Understanding of Its Root Causes

BACKGROUND

When an anastomotic leak is discussed at a typical surgical morbidity and mortality conference, it is often presented as a due to an error in surgical technique involving ischemia, tension, or device failure. Here we assert that without direct visual analysis of the leak site and its tissue histology, an ex post facto claim that an anastomotic leak is due to an error in surgical technique remains speculative.

METHODS

The arguments and rationale used to conclude that an anastomotic leak is due to an error in surgical technique are critically reviewed and assessed for their validity.

RESULTS

No case series or literature exists in which a root cause analysis has been carried out with visual and tissue level evidence to determine the root cause(s) of an anastomotic leak.

CONCLUSIONS

At the individual case level, declaring that an anastomotic leak is due to an error in surgical technique without clear and compelling evidence either visually and/or at the tissue level to substantiate such a claim remains speculative.

Altered gut ecosystems plus the microbiota's potential for rapid evolution: A recipe for inevitable change with unknown consequences

In a single human gut, which is estimated to produce 1000-times more bacteria in a single day than the entire human population on Earth as of 2020, the potential for evolution is vast. In addition to the sheer volume of reproductive events, prokaryotes can transfer most genes horizontally, greatly accelerating their potential to evolve. In the face of this evolutionary potential, Westernization has led to profound changes in the ecosystem of the gut, including increased chronic inflammation in many individuals and dramatically reduced fiber consumption and decreased seasonal variation in the diet of most individuals. Experimental work using a variety of model systems has shown that bacteria will evolve within days to weeks when faced with substantial environmental changes. However, studies evaluating the effects of inflammation of the gut on the microbiota are still in their infancy and generally confounded by the effects of the microbiota on the immune system. At the same time, experimental data indicate that complete loss of fiber from the diet constitutes an extinction-level event for the gut microbiota. However, these studies evaluating diet may not apply to Westernized humans who typically have reduced but not absent levels of fiber in their diet. Thus, while it is expected that the microbiota will evolve rapidly in the face of Westernization, experimental studies that address the magnitude of that evolution are generally lacking, and it remains unknown to what extent this evolutionary process affects disease and the ability to treat the disease state.

The Association of Gut Microbiota and Complications in Gastrointestinal-Cancer Therapies

The therapy of gastrointestinal carcinomas includes surgery, chemo- or immunotherapy, and radiation with diverse complications such as surgical-site infection and enteritis. In recent years, the microbiome’s influence on different diseases and complications has been studied in more detail using methods such as next-generation sequencing. Due to the relatively simple collectivisation, the gut microbiome is the best-studied so far. While certain bacteria are sometimes associated with one particular complication, it is often just the loss of alpha diversity linked together. Among others, a strong influence of Fusobacterium nucleatum on the effectiveness of chemotherapies is demonstrated. External factors such as diet or specific medications can also predispose to dysbiosis and lead to complications. In addition, there are attempts to treat developed dysbiosis, such as faecal microbiota transplant or probiotics. In the future, the underlying microbiome should be investigated in more detail for a better understanding of the precipitating factors of a complication with specific therapeutic options.

Evaluation of the Effects of Different Dietary Patterns on Breast Cancer: Monitoring Circulating Tumor Cells

The occurrence and development of breast cancer are closely related to dietary factors, especially dietary patterns. This study was to investigate the effects of dietary patterns on the process of tumor metastasis by in vivo circulating tumor cell (CTC) capture strategy and monitoring changes of CTC numbers in breast tumor mice model. Meanwhile, the effects of different dietary patterns on the development of lung metastases of breast cancer and the volume and weight of carcinoma in situ were investigated. In this study, the increase in the number of CTCs was significantly promoted by dietary patterns such as high-salt diet, high-sugar diet, and high-fat diet, while it was delayed by ketogenic diet, low-fat diet, low-protein diet, diet restriction, and Mediterranean diet. These results indicated that the in vivo capture and detection of CTCs provides a convenient method for real-time cancer metastasis monitoring, and through in-depth study of the effects of different dietary patterns on tumor growth and metastasis, it can expand a new horizon in future cancer treatments.

Association of Habitual Preoperative Dietary Fiber Intake With Complications After Colorectal Cancer Surgery

IMPORTANCE

Postoperative complications are associated with increased morbidity and mortality among patients with colorectal cancer. As a modifiable factor associated with gut health, dietary fiber intake is of interest with regard to the risk of complications after surgery for colorectal cancer.

OBJECTIVE

To examine the association between preoperative dietary fiber intake and risk of complications after surgery for colorectal cancer.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used data from the Colorectal Longitudinal, Observational Study on Nutritional and Lifestyle Factors (COLON) study, which recruited adult patients with colorectal cancer at any stage at diagnosis from 11 hospitals in the Netherlands between August 2010 and December 2017. The present study included patients with stage I to IV colorectal cancer who underwent elective abdominal surgery. Data were analyzed between December 2019 and September 2020.

EXPOSURES

Habitual dietary fiber intake was assessed at diagnosis using a 204-item food frequency questionnaire.

MAIN OUTCOMES AND MEASURES

Any complications, surgical complications, and anastomotic leakage occurring during the 30 days after surgery for colorectal cancer. The association between fiber intake and risk of postoperative complications was assessed using logistic regression analyses. Additional analyses stratified by sex, tumor location, and fiber source were performed.

RESULTS

Among the 1399 patients included in the analysis, the median age at inclusion was 66 years (interquartile range, 61-72 years) and 896 (64%) were men. Any complications occurred in 397 patients (28%), and surgical complications occurred in 235 patients (17%). Of 1237 patients with an anastomosis, 67 (5%) experienced anastomotic leakage. Higher dietary fiber intake (per 10 g per day) was associated with a lower risk of any complications (odds ratio [OR], 0.75; 95% CI, 0.62-0.92) and surgical complications (OR, 0.76; 95% CI, 0.60-0.97), whereas no association with anastomotic leakage was found (OR, 0.97; 95% CI, 0.66-1.43). Among women, higher dietary intake was associated with any complications (OR, 0.64; 95% CI, 0.44-0.94), whereas there was no association among men (OR, 0.79; 95% CI, 0.63-1.01). Fiber intake from vegetables (per 1 g per day) was inversely associated with any (OR, 0.90; 95% CI, 0.83-0.99) and surgical (OR, 0.87; 95% CI, 0.78-0.97) complications.

CONCLUSIONS AND RELEVANCE

In this cohort study, higher habitual dietary fiber intake before surgery was associated with a lower risk of postoperative complications among patients with colorectal cancer. The findings suggest that improving preoperative dietary fiber intake may be considered in future prehabilitation programs for patients undergoing surgery for colorectal cancer.

Factors Affecting Gut Microbiome in Daily Diet

There is a growing recognition that a good diet can help people maintain mental and physical health, while a bad one will cause the disorder of body function, and even lead to several diseases. A lot of attentions have been devoted to analyze every possible health-related factor in the daily diet, including food ingredients, additives, and cooking process. With the support of high-throughput sequencing technology, there is accumulating evidence gradually clarifying that most of these factors are mainly through the interactions with gut microbiome to trigger downstream effects. The gut microbiome may be able to act as a very sensitive mirror in response to human daily diet. A complex network of interactions among diet, gut microbiome, and health has been gradually depicted, but it is rarely discussed from a more comprehensive perspective. To this end, this review summarized the latest updates in diet-gut microbiome interactions, analyzed most identified factors involved in this process, showed the possibility of maintaining health or alleviating diseases by diet intervention, aiming to help people choose a suitable recipe more accurately.

Progress in the esophagogastric anastomosis and the challenges of minimally invasive thoracoscopic surgery

The esophagogastric anastomosis is most commonly performed to restore digestive tract continuity after esophagectomy for cancer. Despite a long history of clinical research and development of high-tech staplers, this procedure is still feared by most surgeons and associated with a 10% leakage rate. Among specific factors that may contribute to failure of the esophageal anastomosis are the absence of serosa layer, longitudinal orientation of muscle fibers, and ischemia of the gastric conduit. It has recently been suggested that the gut microbiome may influence the healing process of the anastomosis through the presence of collagenolytic bacterial strains, indicating that suture breakdown is not only a matter of collagen biosynthesis. The esophagogastric anastomosis can be performed either in the chest or neck, and can be completely hand-sewn, completely stapled (circular or linear stapler), or semi-mechanical (linear stapler posterior wall and hand-sewn anterior wall). Because of the lack of randomized clinical trials, no conclusive evidence is available, and the debate between the hand-sewn and the stapling technique is still ongoing even in the present era of robotic surgery. Centralization of care has improved the overall postoperative outcomes of esophagectomy, but the esophagogastric anastomosis remains the Achille’s heel of the procedure. More research and network collaboration of experts is needed to improve safety and clinical outcomes.

Anastomotic leak risk in complete responders to neoadjuvant therapy for rectal cancer: a systematic review

PURPOSE

The oncological benefits of achieving a complete pathological response following neoadjuvant chemoradiotherapy for rectal cancer are well defined. How a pathological response affects anastomotic healing or leak rates is not clear. The aim of this systematic review was to compare anastomotic leak rates among patients who did and did not achieve a complete pathological response.

METHODS

Three major databases (PubMed, Embase, and Scopus) were searched. Predetermined inclusion criteria included prospective and retrospective articles published in English reporting complete pathological response and anastomotic leak rates following total mesorectal excision in ≥ 30 patients with rectal cancer who underwent neoadjuvant chemoradiotherapy and total mesorectal excision. The primary outcomes measured included complete pathological response and 30-day postoperative morbidity.

RESULTS

From a total of 8919 patients with rectal cancer in 7 studies, 4165 fulfilled the criteria for inclusion. The majority (> 80%) of patients had clinical stage II or III disease. A defunctioning loop ileostomy was formed in 76.5%. A total of 589 (14.1%) patients achieved a pCR of whom 63 (10.7%) developed an anastomotic leak compared to 272/3576 (7.6%) patients without a pCR (p = 0.02).

CONCLUSION

Patients with complete pathological response following neoadjuvant chemoradiotherapy and total mesorectal excision may be at higher risk of anastomotic leak than incomplete responders. This may need to be taken into account when counseling patients about the relative risks of organ preservation versus anterior resection.

Video is better: why aren't we using it? A mixed-methods study of the barriers to routine procedural video recording and case review

INTRODUCTION

Video-based case review for minimally invasive surgery is immensely valuable for education and quality improvement. Video review can improve technical performance, shorten the learning curve, disseminate new procedures, and improve learner satisfaction. Despite these advantages, it is underutilized in many institutions. So far, research has focused on the benefits of video, and there is relatively little information on barriers to routine utilization.

METHODS

A 36-question survey was developed on video-based case review and distributed to the SAGES email list. The survey included closed and open-ended questions. Numeric responses and Likert scales were compared with t-test; open-ended responses were reviewed qualitatively through rapid thematic analysis to identify themes and sub-themes.

RESULTS

642 people responded to the survey for a response rate of 11%. 584 (91%) thought video would improve the quality of educational conferences. 435 qualitative responses on the value of video were analyzed, and benefits included (1) improved understanding, (2) increased objectivity, (3) better teaching, and (4) better audience engagement. Qualitative comments regarding specific barriers to recording and editing case video identified challenges at all stages of the process, from (1) the decision to record a case, (2) starting the recording in the OR, (3) transferring and storing files, and (4) editing the file. Each step had its own specific challenges.

CONCLUSION

Minimally invasive surgeons want to increase their utilization of video-based case review, but there are multiple practical challenges to overcome. Understanding these barriers is essential in order to increase use of video for education and quality improvement.

Evolution of bacteria in the human gut in response to changing environments: An invisible player in the game of health

Several factors in Western society, including widespread use of antibiotics, chronic inflammation, and loss of complex eukaryotic symbionts such as helminths, have a dramatic impact on the ecosystem of the gut, affecting the microbiota hosted there. In addition, reductions in dietary fiber are profoundly impactful on the microbiota, causing extensive destruction of the niche space that supports the normally diverse microbial community in the gut. Abundant evidence now supports the view that, following dramatic alterations in the gut ecosystem, microorganisms undergo rapid change via Darwinian evolution. Such evolutionary change creates functionally distinct bacteria that may potentially have properties of pathogens but yet are difficult to distinguish from their benign predecessors.

The Role of the Intestinal Microbiome on Colorectal Cancer Pathogenesis and its Recurrence Following Surgery

Colorectal cancer is the result of multiple genetic mutations that drive normal cells to adenoma and then carcinoma. Recent technology has evolved to allow for an in-depth examination of the microbiota and it has become clear that many components of the intestinal microbiome play a role in promoting carcinogenesis. This review aims to describe the potential mechanisms that lead to the dysbiosis that initiates tumor formation and that influence the development of cancer recurrence following surgical resection. We further discuss how manipulation of the microbiome may be a future novel strategy to prevent both primary and secondary colorectal cancer. While we discuss how bacterial communities and individual strains can promote cancer, the microbiome is individualized, dynamic, and complex, and our understanding of its role in carcinogenesis is still in its infancy.

The Biology of Anastomotic Healing-the Unknown Overwhelms the Known

BACKGROUND

Anastomotic complications are among the most devastating consequences of gastrointestinal surgery. Despite its high morbidity, the factors responsible for anastomotic regeneration following surgical construction remain poorly understood. The aim of this review is to provide an overview of the typical and atypical factors that have been implicated in anastomotic healing.

METHODS

A review and analysis of select literature on anastomotic healing was performed.

RESULTS

The healing of an anastomotic wound mirrors the phases of cutaneous wound healing- inflammation, proliferation, and remodeling. The evidence supporting much of the traditional dogma for optimal anastomotic healing (ischemia, tension, nutrition) is sparse. More recent research has implicated atypical factors that influence anastomotic healing, including the microbiome, the mesentery, and geometry. As technology evolves, endoscopic approaches may improve anastomotic healing and in some cases may eliminate the anastomosis altogether.

DISCUSSION

Much remains unknown regarding the mechanisms of anastomotic healing, and research should focus on elucidating the dynamics of healing at a molecular level. Doing so may help facilitate the transition from traditional surgical dogma to evidence-based medicine in the operating room.

Comparative genetics of Enterococcus faecalis intestinal tissue isolates before and after surgery in a rat model of colon anastomosis

We have recently demonstrated that collagenolytic Enterococcus faecalis plays a key and causative role in the pathogenesis of anastomotic leak, an uncommon but potentially lethal complication characterized by disruption of the intestinal wound following segmental removal of the colon (resection) and its reconnection (anastomosis). Here we hypothesized that comparative genetic analysis of E. faecalis isolates present at the anastomotic wound site before and after surgery would shed insight into the mechanisms by which collagenolytic strains are selected for and predominate at sites of anastomotic disruption. Whole genome optical mapping of four pairs of isolates from rat colonic tissue obtained following surgical resection (herein named “pre-op” isolates) and then 6 days later from the anastomotic site (herein named “post-op” isolates) demonstrated that the isolates with higher collagenolytic activity formed a distinct cluster. In order to perform analysis at a deeper level, a single pair of E. faecalis isolates (16A pre-op and 16A post-op) was selected for whole genome sequencing and assembled using a hybrid assembly algorithm. Comparative genomics demonstrated absence of multiple gene clusters, notably a pathogenicity island in the post-op isolate. No differences were found in the fsr-gelE-sprE genes (EF1817-1822) responsible for regulation and production of collagenolytic activity. Analysis of unique genes among the 16A pre-op and post-op isolates revealed the predominance of transporter systems-related genes in the pre-op isolate and phage-related and hydrolytic enzyme-encoding genes in the post-op isolate. Despite genetic differences observed between pre-op and post-op isolates, the precise genetic determinants responsible for their differential expression of collagenolytic activity remains unknown.