Do we really know why colorectal anastomoses leak?

Intraoperative left-sided colorectal anastomotic testing in clinical practice: a multi-treatment machine-learning analysis of the iCral3 prospective cohort

BACKGROUND

Current evidence about intraoperative anastomotic testing after left-sided colorectal resections is still controversial. The aim of this study was to analyze the impact of Indocyanine Green fluorescent angiography (ICG-FA) and air-leak test (ALT) over standard assessment on anastomotic leakage (AL) rates according to surgeon's perception of anastomosis perfusion and/or integrity in clinical practice.

METHODS

A database of 2061 patients who underwent left-sided colorectal resections was selected from patients enrolled in a prospective multicenter study. It was retrospectively analyzed through a multi-treatment machine-learning model considering standard visual assessment (NW; No. = 899; 43.6%) as the reference treatment arm, compared to ICG-FA alone (WP; No. = 409; 19.8%), ALT alone (WI; No. = 420; 20.4%) or both (WPI; No. = 333; 16.2%). Twenty-four covariates potentially affecting the outcomes were included and balanced into the model within the subgroups. The primary endpoint was AL, the secondary endpoints were overall morbidity (OM), major morbidity (MM), reoperation for AL, and mortality. All the results were reported as odds ratio (OR) with 95% confidence intervals (95%CI).

RESULTS

The WPI subgroup showed significantly higher AL risk (OR 1.91; 95% CI 1.02-3.59; p 0.043), MM risk (OR 2.35; 95% CI 1.39-3.97; p 0.001), and reoperation for AL risk (OR 2.44; 95% CI 1.12-5.31; p 0.025). No other significant differences were recorded.

CONCLUSIONS

This study showed that the surgeons' perception of both anastomotic perfusion and integrity (WPI subgroup) was associated to a significantly higher risk of AL and related morbidity, notwithstanding the extensive use of both ICG-FA and ALT testing.

Can Neoadjuvant Chemotherapy Cause Postoperative Hydronephrosis After Radical Cystectomy?

OBJECTIVE

This study's objective is to assess the effect of preoperative factors on postoperative hydroureteronephrosis (HUN) after radical cystectomy (RC) in patients with bladder cancer (BC).

METHODOLOGY

Patients who underwent RC for BC between January 2019 and November 2022 and had unilateral or bilateral postoperative HUN were retrospectively analyzed. Patients without preoperative HUN but with postoperative HUN constituted the patient group, while patients without both preoperative and postoperative HUN constituted the control group, and they were compared with each other.

RESULTS

Neoadjuvant chemotherapy (NAC) and postoperative metastasis were positively correlated with postoperative HUN (r = 0.238, P = 0.007, and r = 0.203, P = 0.021, respectively). Multivariate logistic regression analysis showed that the postoperative HUN was significantly associated with NAC (P = 0.048; Exp(B) = 6.896, 95% confidence interval [CI] 1.02-46.9) but not associated with the presence of metastasis (P = 0.054). Moreover, NAC increased the possibility of undergoing revision surgery (P = 0.002; Exp(B) = 26.9, 95% CI 3.2-225).

CONCLUSIONS

NAC is an independent factor for impaired anastomotic healing, increased postoperative HUN, and the need for revision surgery in patients with BC.

Pelvic Floor Peritoneum Closure Reduces Severe Postoperative Complications in Rectal Cancer Patients After Laparoscopic Anterior Rectal Resection

BACKGROUND

Laparoscopic anterior rectal resection (LAR) is a commonly performed surgery for rectal cancer patients. Pelvic floor peritoneum closure (PC), a vital procedure in conventional anterior rectal resection, is not routinely performed in LAR.

STUDY DESIGN

A total of 1118 consecutive patients with rectal cancer receiving LAR were included in this retrospective study. Patients were allocated into the PC group and the non-PC group. The occurrence of postoperative complications was compared between the 2 groups. Influential factors in anastomotic leakage (AL) were explored using univariate and multivariate logistic regression.

RESULTS

There was no difference between the groups in terms of baseline characteristics. The occurrence of postoperative complications was similar between the groups. The PC group had significantly shorter postoperative hospitalization and longer operation duration compared with the non-PC group. The occurrences of Clavien-Dindo (CD) III-IV complications, CD III-IV AL, and reoperation were significantly lower in the PC group than the non-PC group. PC and a protective ileostomy were independent protective factors for CD III-IV AL.

CONCLUSION

PC could reduce the occurrence of CD III-IV complications, especially CD III-IV AL, and the rate of secondary surgery, especially in patients with a lower body mass index and patients who did not receive protective ileostomies.

Efficacy of Biomarkers in Predicting Anastomotic Leakage After Gastrointestinal Resection: A Systematic Review and Meta-Analysis

Our systematic review and meta-analysis were designed to evaluate the published literature from 2016 to 2019 on which the role of biomarkers in predicting the anastomotic leakage (AL) in gastroesophageal cancer surgery was investigated. This extensive literature search was conducted on the principles of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. PubMed, Medical Literature Analysis and Retrieval System Online (MEDLINE), and Excerpta Medica dataBASE (EMBASE) were used to gather the relevant information. No restrictions were made on the type of biomarkers. Wald or likelihood ratio (LRT) fixed effect tests were used to estimate the pooled prevalence to generate the proportions with 95% confidence intervals (CI) and model-fitted weights. For analyzing heterogeneity, the Cochran Q test and I square test were used. The Egger regression asymmetry test and funnel plot were used for publication. In this meta-analysis, a total of 15 studies were recruited with 1892 patients undergoing the resection. The pooled elevated C-reactive protein (CRP) was observed as 13.9% ranging from 11.6% to 16.1%. The pooled prevalence of other biomarkers with AL was observed as 4.4%. Significant heterogeneity was observed between studies that reported CRP and other biomarkers (92% each with chi-squared values of 78.80 and 122.78, respectively). However, no significant publication was observed between studies (p=0.61 and p=0.11, respectively). We concluded our study on this note that different biomarkers are involved in the diagnosis of AL. However, all these biomarkers are poor predictors with insufficient predictive value and sensitivity.

Bio-Inspired Self-Healing, Shear-Thinning, and Adhesive Gallic Acid-Conjugated Chitosan/Carbon Black Composite Hydrogels as Suture Support Materials

The occurrence of leakage from anastomotic sites is a significant issue given its potential undesirable complications. The management of anastomotic leakage after gastrointestinal surgery is particularly crucial because it is directly associated with mortality and morbidity in patients. If adhesive materials could be used to support suturing in surgical procedures, many complications caused by leakage from the anastomosis sites could be prevented. In this study, we have developed self-healing, shear-thinning, tissue-adhesive, carbon-black-containing, gallic acid-conjugated chitosan (CB/Chi-gallol) hydrogels as sealing materials to be used with suturing. The addition of CB into Chi-gallol solution resulted in the formation of a crosslinked hydrogel with instantaneous solidification. In addition, these CB/Chi-gallol hydrogels showed enhancement of the elastic modulus (G') values with increased CB concentration. Furthermore, these hydrogels exhibited excellent self-healing, shear-thinning, and tissue-adhesive properties. Notably, the hydrogels successfully sealed the incision site with suturing, resulting in a significant increase in the bursting pressure. The proposed self-healing and adhesive hydrogels are potentially useful in versatile biomedical applications, particularly as suture support materials for surgical procedures.

How to reduce the colorectal anastomotic leakage? The MIRACLe protocol experience in a cohort in a single high-volume centre

This article reports the results of a novel perioperative treatment implementing the gut microbiota to prevent anastomotic fistula and leakage (AL) in patients undergoing laparoscopic colorectal resections for cancer and represents the continuation of our pilot study on 60 cases. A series of 131 patients underwent elective colorectal surgery at the S. Eugenio Hospital (Rome-Italy) between December 1, 2020, and November 30, 2022, and received a perioperative preparation following the Microbiota Implementation to Reduce Anastomotic Colorectal Leaks (MIRACLe) protocol comprising oral antibiotics, mechanical bowel preparation and perioperative probiotics. The results obtained in the MIRACLe group (MG) were compared to those registered in a Control group (CG) of 500 patients operated on between March 2015 and November 30, 2020, who received a standard ERAS protocol. Propensity score-matching (PSM) analysis was performed to overcome patients' selection bias. Patients were categorised according to perioperative preparation (MIRACLe protocol vs standard ERAS protocol) into two groups: 118 patients were in post-matched MIRACLe group (pmMG) and 356 were in post-matched Control group (pmCG). In the pmMG, only 2 anastomotic leaks were registered, and the incidence of AL was just 1.7% vs. 6.5% in the pmCG (p = 0.044). The incidence of surgical site infections (1.7% vs. 3.1%; p = 0.536), reoperations (0.8% vs. 4.2%; p = 0.136) and postoperative mortality (0% vs. 2.0%; p = 0.200) was lower in pmMG. Additionally, the postoperative outcomes were better: the times to first flatus, to first stool and to oral feeding were shorter (1 vs. 2, 2 vs. 3 and 2 vs. 3 days, respectively; p < 0.001). The postoperative recovery was faster, with a shorter time to discharge (5 vs. 6 days; p < 0.001). The MIRACLe protocol was confirmed to be safe and significantly able to reduce anastomotic leaks in patients receiving elective laparoscopic colorectal surgery for cancer.

Indocyanine green angiography for lower incidence of anastomotic leakage after transanal total mesorectal excision: a propensity score-matched cohort study

Background

Anastomotic leakage (AL) is the most serious complication that can arise during colorectal surgery. Indocyanine green (ICG) angiography offers an intraoperative assessment of colonic vascular perfusion in real time. We aimed to assess ICG's effects on the AL rate in patients who have undergone transanal total mesorectal excision (TaTME) for rectal cancer.

Methods

This retrospective cohort study was conducted at our center from October 2018 to March 2022 to analyze the clinical data of patients with rectal cancer who have undergone TaTME after propensity score matching (PSM). The primary outcome was the proximal colonic transection line modification and clinical AL rate.

Results

A total of 143 patients in the non-ICG group and 143 patients in the ICG group were included after PSM. The proximal colonic transection line of seven patients in the non-ICG group was modified, while 18 were in the ICG group (4.9% vs. 12.5%, p = 0.023). Twenty-three patients (16.1%) in the non-ICG group and five patients (3.5%) in the ICG group were diagnosed with AL (p < 0.001). The ICG group had a less hospital readmission rate than the non-ICG group (0.7% vs. 7.7%, p = 0.003). The between-group differences in basic line and other outcomes were not significant.

Conclusions

ICG angiography is a safe and feasible method to help surgeons identify potentially poor colonic vascular perfusion and modify the proximal colonic transection line, resulting in a significant reduction in AL and hospital readmission rates.

Safety of early pelvic drain removal in colorectal surgery based on drainage quantity

BACKGROUND

This study aimed to investigate the association between the drainage quantity of pelvic drains and postoperative complications in colorectal surgery.

MATERIALS AND METHODS

This retrospective single-center study enrolled 122 colorectal surgery patients between January 2017 and December 2020. After restorative proctectomy or proctocolectomy with gastrointestinal anastomosis, a continuous, low-pressure suction pelvic drain was placed and its contents measured. Removal ensued following the absence of turbidity and a drainage quantity of ≤ 150 mL/day.

RESULTS

Seventy-five patients (61.5%) and 47 patients (38.5%) underwent restorative proctectomy and proctocolectomy, respectively. Drainage quantity changes were observed on postoperative day (POD) 3, regardless of the surgical procedure or postoperative complications. The median (interquartile range) number of PODs before drain removal and organ-space surgical site infection (SSI) diagnosis were 3 (3‒5) and 7 (5‒8), respectively. Twenty-one patients developed organ-space SSIs. Drains were left in place in two patients after POD 3 owing to large drainage quantities. Drainage quality changes enabled diagnosis in two patients (1.6%). Four patients responded to therapeutic drains (3.3%).

CONCLUSIONS

The drainage quantity of negative-pressure closed suction drains diminishes shortly after surgery, regardless of the postoperative course. It is not an effective diagnostic or therapeutic drain for organ-space SSI. This supports early drain removal based on drainage quantity changes in actual clinical practice.

TRIAL REGISTRATION

The study protocol was retrospectively registered and carried out per the Declaration of Helsinki and approved by the Hiroshima University Institutional Review Board (approval number: E-2559).

Crohn's Disease as a Possible Risk Factor for Failed Healing in Ileocolic Anastomoses

Anastomotic leakage (AL) after colorectal resections is a serious complication in abdominal surgery. Especially in patients with Crohn's disease (CD), devastating courses are observed. Various risk factors for the failure of anastomotic healing have been identified; however, whether CD itself is independently associated with anastomotic complications still remains to be validated. A retrospective analysis of a single-institution inflammatory bowel disease (IBD) database was conducted. Only patients with elective surgery and ileocolic anastomoses were included. Patients with emergency surgery, more than one anastomosis, or protective ileostomies were excluded. For the investigation of the effect of CD on AL 141, patients with CD-type L1, B1-3 were compared to 141 patients with ileocolic anastomoses for other indications. Univariate statistics and multivariate analysis with logistic regression and backward stepwise elimination were performed. CD patients had a non-significant higher percentage of AL compared to non-IBD patients (12% vs. 5%, p = 0.053); although, the two samples differed in terms of age, body mass index (BMI), Charlson comorbidity index (CCI), and other clinical variables. However, Akaike information criterion (AIC)-based stepwise logistic regression identified CD as a factor for impaired anastomotic healing (final model: p = 0.027, OR: 17.043, CI: 1.703-257.992). Additionally, a CCI ≥ 2 (p = 0.010) and abscesses (p = 0.038) increased the disease risk. The alternative point estimate for CD as a risk factor for AL based on propensity score weighting also resulted in an increased risk, albeit lower (p = 0.005, OR 7.36, CI 1.82-29.71). CD might bear a disease-specific risk for the impaired healing of ileocolic anastomoses. CD patients are prone to postoperative complications, even in absence of other risk factors, and might benefit from treatment in dedicated centers.

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.

Predictive Factors for Anastomotic Leakage Following Colorectal Cancer Surgery: Where Are We and Where Are We Going?

Anastomotic leakage (AL) remains one of the most severe complications following colorectal cancer (CRC) surgery. Indeed, leaks that may occur after any type of intestinal anastomosis are commonly associated with a higher reoperation rate and an increased risk of postoperative morbidity and mortality. At first, our review aims to identify specific preoperative, intraoperative and perioperative factors that eventually lead to the development of anastomotic dehiscence based on the current literature. We will also investigate the role of several biomarkers in predicting the presence of ALs following colorectal surgery. Despite significant improvements in perioperative care, advances in surgical techniques, and a high index of suspicion of this complication, the incidence of AL remained stable during the last decades. Thus, gaining a better knowledge of the risk factors that influence the AL rates may help identify high-risk surgical patients requiring more intensive perioperative surveillance. Furthermore, prompt diagnosis of this severe complication may help improve patient survival. To date, several studies have identified predictive biomarkers of ALs, which are most commonly associated with the inflammatory response to colorectal surgery. Interestingly, early diagnosis and evaluation of the severity of this complication may offer a significant opportunity to guide clinical judgement and decision-making.

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.

Efficacy of a transanal drainage tube versus diverting stoma in protecting colorectal anastomosis: a systematic review and meta-analysis

Anastomotic leakage (AL) is the most fearsome complication in low rectal resection. The temporary diverting stoma (DS) is recommended to prevent AL, but it may cause relevant morbidity and needs a second surgical procedure to be closed. Therefore, the use of a transanal drainage tube (TDT) has been proposed as an alternative. We performed a systematic review and meta-analysis concerning the peri-operative outcomes in patients undergoing elective anterior rectal resection (ARR) with TDT alone or DS alone. Six studies were meta-analyzed, including a total of 735 patients. The meta-analysis showed that the incidences of AL, surgery-related complications, infective complications, and 30-day reoperation after ARR with low colorectal or coloanal anastomosis did not differ significantly between patients undergoing positioning of TDT and those undergoing DS. Furthermore, overall complications were significantly rarer in patients undergoing TDT. A meta-analysis of the randomized control trial (RCT) and no-RCT subgroups did not detect any statistically significant differences in any outcomes. These results suggest that it might be reasonable to employ a TDT in place of a DS to protect low colorectal and coloanal anastomosis, with consequent considerable advantages in terms of the short- and long-term post-operative outcomes. However, more well-designed RCTs are needed to definitively assess this issue.

Mechanical bowel preparation combined with oral antibiotics reduces infectious complications and anastomotic leak in elective colorectal surgery: a pooled-analysis with trial sequential analysis

OBJECTIVE

A pooled analysis combined with trial sequential analysis (TSA) was conducted in order to explore the effect of mechanical bowel preparation (MBP) combined with oral antibiotic bowel decontamination (OAB) versus MBP alone on patients who have undergone colorectal resection.

METHODS

Comprehensive and systematic searches of PubMed, Embase, Cochrane Library, Web of Knowledge, and Clinical Trials.gov databases were conducted. The quality of literature was evaluated using Cochrane risk bias assessment tool as well as Newcastle-Ottawa Scale (NOS) score. A pooled analysis of randomized controlled trials (RCTs) and prospective studies was performed comparing patients who underwent colorectal resection and received MBP plus OAB or MBP alone. The outcome endpoints were the incidence of anastomotic leak (AL) and surgical site infection (SSI). TSA is a tool used to assess the reliability of currently available evidence to determine further clinical trial validation.

RESULTS

The analysis included a total of 22 studies involving 8852 patients, including 3016 patients in the MBP + OAB group and 4415 patients exposed to MBP alone. The pooled analysis showed that the incidence of postoperative anastomotic leak was significantly lower in the group treated with MBP plus OAB compared with MBP alone (OR = 0.43, 95% CI: 0.23-0.81, P = 0.009, I2 = 73%). The incidence of postoperative surgical site infections was significantly lower in the group exposed to the combination of MBP and OAB compared with MBP alone (OR = 0.38, 95% CI: 0.32-0.46, P < 0.0001, I2 = 24%). The TSA demonstrated significant benefits of MBP plus OAB intervention in terms of AL and SSI.

CONCLUSION

MBP combined with OAB significantly reduces the incidence of AL and SSI in patients after colorectal resection compared with MBP alone.

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.

A Narrative Review of the Usefulness of Indocyanine Green Fluorescence Angiography for Perfusion Assessment in Colorectal Surgery

Anastomotic leakage is one of the most dreaded complications of colorectal surgery and is strongly associated with tissue perfusion. Indocyanine green fluorescence angiography (ICG-FA) using indocyanine green and near-infrared systems is an innovative technique that allows the visualization of anastomotic perfusion. Based on this information on tissue perfusion status, surgeons will be able to clearly identify colorectal segments with good blood flow for safer colorectal anastomosis. The results of several clinical trials indicate that ICG-FA may reduce the risk of AL in colorectal resection; however, the level of evidence is not high, as several other studies have failed to demonstrate a reduction in the risk of AL. Several large-scale RCTs are currently underway, and their results will determine whether ICG-FA is, indeed, useful. The major limitation of the current ICG-FA evaluation method, however, is that it is subjective and based on visual assessment by the surgeon. To complement this, the utility of objective evaluation methods for fluorescence using quantitative parameters is being investigated. Promising results have been reported from several clinical trials, but all trials are preliminary owing to their small sample size and lack of standardized protocols for quantitative evaluation. Therefore, appropriately standardized, high-quality, large-scale studies are warranted.

The role of transanal drainage tube in preventing the anastomotic leakage in rectal cancer surgery without a defunctioning stoma: A meta-analysis

BACKGROUND

Anastomotic leakage is a common and serious complication after rectal cancer surgery. The role of transanal drainage tube (TDT) in the prevention of anastomotic leakage is still controversial. The aim of this study was to evaluate the role of TDT in preventing anastomotic leakage.

METHODS

Two reviewers individually searched the PubMed, Embase and Cochrane Library ranging from January 2000 to June 2022. The pooled odds ratio (ORs) and weighted mean difference (WMD) with the 95% confidence interval (95% CI) were used to assess anastomotic leakage and other parameters.

RESULTS

A total of 3383 patients (1508 in the TDT group and 1875 in the cohort study group) were included in 13 studies. The study found that patients treated with TDT had a lower incidence of anastomotic leakage with or without neoadjuvant radiotherapy. Moreover, patients who received TDT had lower rates of reoperation and tended to reduce the severity of anastomotic leakage.

CONCLUSIONS

For rectal cancer patients without defunctioning stoma, TDT could reduce the incidence of anastomotic leakage, decrease the reoperation rate of patients, and tend to reduce the severity of anastomotic leakage. More RCT are needed to assess the role of TDT in rectal cancer surgery.

New understanding of gut microbiota and colorectal anastomosis leak: A collaborative review of the current concepts

Anastomotic leak (AL) is a life-threatening postoperative complication following colorectal surgery, which has not decreased over time. Until now, no specific risk factors or surgical technique could be targeted to improve anastomotic healing. In the past decade, gut microbiota dysbiosis has been recognized to contribute to AL, but the exact effects are still vague. In this context, interpretation of the mechanisms underlying how the gut microbiota contributes to AL is significant for improving patients' outcomes. This review concentrates on novel findings to explain how the gut microbiota of patients with AL are altered, how the AL-specific pathogen colonizes and is enriched on the anastomosis site, and how these pathogens conduct their tissue breakdown effects. We build up a framework between the gut microbiota and AL on three levels. Firstly, factors that shape the gut microbiota profiles in patients who developed AL after colorectal surgery include preoperative intervention and surgical factors. Secondly, AL-specific pathogenic or collagenase bacteria adhere to the intestinal mucosa and defend against host clearance, including the interaction between bacterial adhesion and host extracellular matrix (ECM), the biofilm formation, and the weakened host commercial bacterial resistance. Thirdly, we interpret the potential mechanisms of pathogen-induced poor anastomotic healing.

Remote ischemic postconditioning has a detrimental effect and remote ischemic preconditioning seems to have no effect on small intestinal anastomotic strength

BACKGROUND

The effect of remote pre- and postconditioning on anastomotic healing has been sparsely studied. The aim of our study was to investigate whether remote ischemic conditioning (RIC) applied before and after the creation of a small bowel anastomosis had an effect on anastomotic healing on postoperative day five evaluated by a tensile strength test and histological analysis.

MATERIALS AND METHODS

Twenty-two female piglets were randomized into two groups. The intervention group (n = 12) received RIC on the forelimbs consisting of 15 min of ischemia followed by 30 min of reperfusion before the first end-to-end ileal anastomosis was created. The RIC procedure was repeated and the second and more distal anastomosis was performed. The control group (n = 10) had two similar anastomoses with similar time intervals but without RIC. On postoperative day five, the anastomoses were subjected to macroscopic evaluation, tensile strength test and histological examination.

RESULTS

Mean tensile strength when the first transmural rupture appeared (MATS-2) was significantly lower in the first anastomosis in the intervention group compared to the control group (11.4 N vs 14.7 N, p < .05). Similar result was found by the maximal strength (MATS-3) as defined by a drop in the load curve (12.3 N vs 15.9 N, p < .05). Histologically, a significantly higher necrosis score was found in the anastomosis in the intervention group (1.4 vs 0.8, p < .05). No other significant differences were found.

CONCLUSIONS

In conclusion, post-anastomotic remote ischemic conditioning had a detrimental effect and pre-anastomotic conditioning seems to have no effect on small intestinal anastomotic strength.

Implementation of the gut microbiota prevents anastomotic leaks in laparoscopic colorectal surgery for cancer:the results of the MIRACLe study

The aim of this pilot study was to evaluate the effects of a novel perioperative treatment for the implementation of the gut microbiota, to prevent anastomotic fistula and leakage (AL) in patients undergoing laparoscopic colorectal resections for cancer. A series of 60 patients who underwent elective colorectal surgery at S. Eugenio Hospital (Rome-Italy) between December 1, 2020 and November 30, 2021 and received a novel perioperative preparation following the MIRACLe (Microbiota Implementation to Reduce Anastomotic Colorectal Leaks) protocol (oral antibiotics, mechanical bowel preparation and perioperative probiotics), was compared to a group of 500 patients (control group) operated on between March 2015 and November 30, 2020, who received a standard ERAS protocol. In the MIRACLe Group only 1 anastomotic leak was registered. In this group the incidence of AL was just 1.7% vs. 6.4% in the control group (p = 0.238) and the incidence of surgical site infections (1.7% vs. 3.6%; p = 0.686), reoperations (1.7% vs. 4.2%; p = 0.547) and postoperative mortality (0% vs. 2.2%; p = 0.504) were lower. The postoperative outcomes were also better: the times to first flatus, to first stool and to oral feeding were shorter (1 vs. 2, 2 vs. 3 and 2 vs. 3 days, respectively; p < 0.001). Additionally, the postoperative recovery was faster, with a shorter time to discharge (4 vs. 6 days; p < 0.001). In this pilot study, the MIRACLe protocol appeared to be safe and considerably reduced anastomotic leaks in elective laparoscopic colorectal surgery for cancer, even if not statistically significant, due to the small number of cases.

Metronidazole Delivery Nanosystem Able To Reduce the Pathogenicity of Bacteria in Colorectal Infection

Metronidazole (MTZ) is a drug potentially used for the treatment of intestinal infections, namely, the ones caused by colorectal surgery. The traditional routes of administration decrease its local effectiveness and present off-site effects. To circumvent such limitations, herein a drug delivery system (DDS) based on MTZ-loaded nanoparticles (NPs) immobilized at the surface of electrospun fibrous meshes is proposed. MTZ at different concentrations (1, 2, 5, and 10 mg mL^-1) was loaded into chitosan-sodium tripolyphosphate NPs. The MTZ loaded into NPs at the highest concentration showed a quick release in the first 12 h, followed by a gradual release. This DDS was not toxic to human colonic cells. When tested against different bacterial strains, a significant reduction of Escherichia coli and Staphylococcus aureus was observed, but no effect was found against Enterococcus faecalis. Therefore, this DDS offers high potential to locally prevent the occurrence of infections after colorectal anastomosis.

Re-laparoscopy to Treat Early Complications After Colorectal Surgery: Is There a Learning Curve?

BACKGROUND

Laparoscopy for treating complications after laparoscopic colorectal surgery (LCS) is still controversial. Moreover, its learning curve has not been evaluated yet. The aim of this study was to analyze whether operative outcomes were influenced by the learning curve of re-laparoscopy.

METHODS

A retrospective analysis of patients undergoing LCS and reoperated by a laparoscopic approach during the period 2000-2019 was performed. A cumulative sum analysis was done to determine the number of operations that must be performed to achieve a stable operative time. Based on this analysis, the cohort was divided in 3 groups. Demographics and operative variables were compared between groups.

RESULTS

From a total of 1911 patients undergoing LCS, 132 (7%) were included. Based on the cumulative sum analysis, the cohort was divided into the first 50 (G1), the following 52 (G2), and the last 30 (G3) patients. Less computed tomography scans were performed in G3 (G1: 72% vs. G2: 63% vs. G3: 43%; P=0.03). There were no differences in the type of operation performed between the groups. The conversion rate (G1: 18% vs. G2: 4% vs. G3: 3%; P=0.02) and the mean operative time (G1: 104 min vs. G2: 80 min vs. G3: 78 min; P=0.003) were higher in G1. Overall morbidity was lower in G3 (G1: 46% vs. G2: 63% vs. G3: 33%; P=0.01). Major morbidity, mortality, and mean length of stay remained similar in all groups.

CONCLUSIONS

A total of 50 laparoscopic reoperations might be needed to achieve an appropriate learning curve with reduced operative time and lower conversion rates. Further research is needed to determine the learning process of re-laparoscopy for treating complications after colorectal surgery.

The Role of Indocyanine Near-Infrared Fluorescence in Colorectal Surgery

Purposes

The aim of this study was to evaluate the importance of Indocyanine Green in control of anastomosis perfusion and on anastomotic leakage rates during laparoscopic and robotic colorectal procedures.

Methods

A retrospective review of patients who underwent elective minimally invasive surgery for colorectal cancer from 1 January 2018 to 31 December 2020 was performed. All patients underwent Near-Infrared Fluorescence-Indocyanine Green system in two moments: before performing the anastomosis and after completing the anastomotic procedure. Primary outcomes were the rate of intraoperative change in the surgical resection due to an inadequate vascularization and the rate of postoperative anastomotic leakage. Secondary outcomes were the postoperative complications, both medical and surgical (intra-abdominal bleeding, anastomotic leakage).

Results

Our analysis included 93 patients. Visible fluorescence was detected in 100% of the cases. In 7 patients (7.5%), the planned site of resection was changed due to inadequate perfusion. The mean extension of the surgical resection in these 7 patients was 2.2 ± 0.62. Anastomotic leakage occurred in 2 patients (2.1%). Other complications included 8 postoperative bleedings (8.6%) and 1 pulmonary thromboembolism.

Conclusions

The intraoperative use of Near-Infrared Fluorescence-Indocyanine Green in colorectal surgery is safe, feasible, and associated with a substantial reduction in postoperative anastomotic leakage rate.

Antibiotic Bowel Decontamination in Gastrointestinal Surgery—A Single-Center 20 Years’ Experience

Objective

Anastomotic leakage, surgical site infections, and other infectious complications are still common complications in gastrointestinal surgery. The concept of perioperative antibiotic bowel decontamination demonstrates beneficial effects in single randomized controlled trials (RCTs), but data from routine clinical use are still sparse. Our aim was to analyze the data from the routine clinical use of perioperative antibiotic bowel decontamination in gastrointestinal surgery.

Methods

Based on 20 years’ experience, we performed a retrospective analysis of all cases in oncologic gastrointestinal surgery with the use of antibiotic bowel decontamination in gastric, sigmoid, and rectal cancer. Clinical data and perioperative outcomes were analyzed, especially regarding anastomotic leakage, surgical site infections, and other infectious complications.

Results

A total of n = 477 cases of gastrointestinal surgery in gastric cancer (n = 80), sigmoid cancer (n = 168), and rectal cancer (n = 229) using a perioperative regimen of antibiotic bowel decontamination could be included in this analysis. Overall, anastomotic leakage occurred in 4.4% (2.5% gastric cancer, 3.0% sigmoid cancer, 6.1% rectal cancer) and surgical site infections in 9.6% (6.3% gastric cancer, 9.5% sigmoid cancer, 10.9% rectal cancer). The incidence of all infectious complications was 13.6% (12.5% gastric cancer, 11.3% sigmoid cancer, 15.7% rectal cancer). Mortality was low, with an overall rate of 1.1% (1.3% gastric cancer, 1.8% sigmoid cancer, 0.4% rectal cancer). Antibiotic decontamination was completed in 98.5%. No adverse effects of antibiotic bowel decontamination could be observed.

Conclusion

Overall, in this large cohort, we can report low rates of surgery-related serious morbidity and mortality when perioperative antibiotic bowel decontamination is performed. The rates are lower than other clinical reports. In our clinical experience, the use of perioperative antibiotic bowel decontamination appears to improve patient safety and surgical outcomes during gastrointestinal oncologic procedures in a routine clinical setting.

The Microbiota and the Relationship with Colorectal Cancer: Surgical Complications—A Review

Colorectal cancer (CRC) is one of the most common cancers and represents a major global health burden. While genetics are implicated in a portion of CRC patients, most cases are sporadic. A new possibility of tumor initiation and promotion might be microbiome composition. It was recently shown that bacteria from the gut microbiome might be used as biomarkers for CRC detection, especially Fusobacterium nucleatum, Peptostreoptococcus stomatis, Parvimonas mica, Solobacterium moorei, and Peptostreptococcus anaerobius. Conversely, the healthy gut microbiome is mostly colonized by Bacterioides (Bacterioides fragilis, vulgatus, uniformis), Firmicutes (Clostridium spp., Ruminococcus faecis, Enterococcus faecium), and Actinobacteria (Bifidobacterium bifidum). Some strains of gut bacteria favor tumor promotion through DNA and RNA damage (directly or through interaction with other known food carcinogens) and through local immune inhibition. It is possible that bacteria (e.g., Bacillus polyfermenticus, Alistipes shahii, Lactobacillus casei) exist with protective functions against tumor promotion. Despite current advances in colorectal cancer treatment, especially in the medical oncology and radiotherapy domains, surgery remains the mainstay of curative treatment for colorectal cancer patients, even in the oligometastatic setting. Surgical complications like anastomotic leakage, excessive blood loss, abscess, and abdominal sepsis can reduce 1-year and 5-year overall survival and increase the recurrence rates for these patients; therefore, we reviewed currently published data focusing on the relationship between gut microbiota and postoperative complications for colorectal cancer patients.

Shifting surgical archetypes of ICG fluorescent-angiography for bowel perfusion assessment in cardiogenic shock under ECMO support

Extracorporeal membrane oxygenation (ECMO) has been adopted to support patients with acute severe cardiac or pulmonary failure that is potentially reversible and unresponsive to conventional management. Mesenteric ischemia (MI) can present as a life-threatening complication in patients receiving veno-arterial echocardiogram (ECHO) support. Due to the nature and acuity of these conditions, determining adequate perfusion upon surgical intervention is challenging for the operating surgeon, especially in cardiogenic shock (CS) patients on ECMO support persenting low arterial pulsatility. Indocyanine green fluorescent angiography (ICG-FA) has proven to be useful for real-time assessment of vascular perfusion, which may help determine the extent of bowel ischemia in patients receiving ECMO support. The case report here-in presented, breaks the paradigm of performing non-cardiac surgical procedures on ECMO support via a pioneering visual aid technique. LEARNING OBJECTIVE: ICG-FA is a promising visual intraoperatory technique providing real-time feedback for the adequate identification and assessment of target tissue/organs. The high morbidity and mortality rates associated to MI and CS-particularly when concomitantly present-hinders salvage surgical therapy. The use of ECMO provides hemodynamic stability This case report highlights the importance of adequate surgical intervention under extracorporeal life support in the presence of both CS and MI. To the authors' knowledge, this is the first report of application of ICG-FA to evaluate mesenteric perfusion in a patient receiving ECMO support.

Risk Factors for Anastomotic Leakage in Advanced Ovarian Cancer Surgery: A Large Single-Center Experience

Background

Cytoreductive surgery is currently the main treatment for advanced epithelial ovarian cancer (OC), and several surgical maneuvers, including colorectal resection, are often needed to achieve no residual disease. High surgical complexity carries an inherent risk of postoperative complications, including anastomosis leakage (AL). Albeit rare, AL is a life-threatening condition. The aim of this single-center retrospective study is to assess the AL rate in patients undergoing colorectal resection and anastomosis during primary surgery for advanced epithelial OC through a standardized surgical technique and to evaluate possible pre/intra- and postoperative risk factors to identify the population at greatest risk.

Methods

A retrospective analysis of clinical and surgical characteristics of 515 patients undergoing colorectal resection and anastomosis during primary or interval debulking surgery between December 2011 and October 2019 was performed. Several pre/intra- and postoperative variables were evaluated by multivariate analysis as potential risk factors for AL.

Results

The overall anastomotic leakage rate was 2.9% (15/515) with a significant negative impact on postoperative course. Body mass index < 18 kg/m², preoperative albumin value lower than 30 mg/dL, section of the inferior mesenteric artery at its origin, and medium–low colorectal anastomosis (< 10 cm from the anal verge) were identified as independent risk factors for AL on multivariate analysis.

Conclusions

AL is confirmed to be an extremely rare but severe postoperative complication of OC surgery, being responsible for increased early postoperative mortality. Preoperative nutritional status and surgical characteristics, such as blood supply and anastomosis level, appear to be the most significant risk factors.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-022-11686-y.

Intraoperative Colonic Irrigation for Low Rectal Resections With Primary Anastomosis: A Fail-Safe Surgical Model

Aim

Regardless the technological developments in surgery, the anastomotic leakage (AL) rate of low rectal anastomosis remains high. Though various perioperative protocols have been tested to reduce the risk for AL, there is no standard peri-operative management approach in rectal surgery. We aim to assess the short-term outcome of a multidisciplinary approach to reduce the rates of ALs using a fail-safe-model using preoperative and intraoperative colonic irrigation in low rectal resections with primary anastomosis.

Methods

Between January 2015 and December 2020, 92 patients received low rectal resections for rectal cancer with primary anastomosis and diverting ileostomy. All these patients received pre-operative mechanical bowel preparation (MBP) without antibiotics as well as intraoperative colonic irrigation. The intraoperative colonic irrigation was performed via the efferent loop of the ileostomy. All data were analyzed by SPSS for descriptive and inferential analyses.

Results

In the study period, 1.987 colorectal surgical procedures were performed. This study reports AL in 3 (3.3%) of 92 recruited patients. Other postoperative complications (Dindo-Clavien I-IV) were reported in 25 patients (27.2%), which occurred mainly due to non-surgical reasons such as renal dysfunction and sepsis. According to the fail-safe model, AL was treated by endoscopic or re-do surgery. The median postoperative length of hospitalization was 8 days (4–45) days.

Conclusion

This study validates the effectiveness of a multi-disciplinary fail-safe model with a pre-operative MBP and an intraoperative colonic irrigation in reducing AL rates. Intraoperative colonic irrigation is a feasible approach that lowers the AL rates by reducing fecal load and by decontamination of the colon and anastomotic region. Our study does not recommend a pre-operative administration of oral antibiotics for colorectal decontamination.

Feasibility of quantitative analysis of colonic perfusion using indocyanine green to prevent anastomotic leak in colorectal surgery

BACKGROUND

The aim of this study was to quantify Fluorescence angiography with indocyanine green (ICG) in colorectal cancer anastomosis, determine influential factors in its temporary intensity and pattern, assessing the ability to predict the AL, and setting the cut-off levels to establish high- or low-risk groups.

METHODS

Retrospective analysis of prospectively managed database, including 70 patients who underwent elective surgery for colorectal cancer in which performing a primary anastomosis was in primary plan. In all of them, ICG fluorescence angiography was performed as usual clinical practice with VisionSense™ VS Iridium (Medtronic, Mansfield, MA, USA), in Elevision™ IR Platform (Medtronic, Mansfield, MA, USA). Parameters measured at real time or calculated were T₀, T_max, ∆T, F_max, %_pos, F_pos, and Slope.

RESULTS

70 patients were included, 69 anastomosis were performed and one end colostomy. Arterial hypertension demonstrated higher F_max, as well as the location of the anastomosis (the nearest to rectum, the most intensity detected). A statistical relationship was found between AL and the lower F_pos and Slope. The decision of changing the subjectively decided point of division did not demonstrate statistical difference on the further development of AL. All parameters were analyzed to detect the cut-off related with AL. Only in case of F_pos lower than 158.3 U and Slope lower than 13.1 U/s p-value were significant. The most valuable diagnostic parameter after risk stratification was the Negative Predictive Value.

CONCLUSION

Quantitative analysis of ICG fluorescence in colorectal surgery is safe and feasible to stratify risk of AL. Hypertension and location of anastomosis influence the intensity of fluorescence at the point of section. A change of division place should be considered to avoid AL related to vascular reasons when intensities of fluorescence at the point of section is lower than 169 U or slopes lower than 14.4 U/s.

OUP accepted manuscript

Background

Methods

Results

Conclusion

In-hospital economic burden of anastomotic leakage after colorectal anastomosis surgery: a real-world cost analysis in Italy

BACKGROUND

Anastomotic leakage (AL) is a severe complication of colorectal surgery. We aimed to quantify inpatient costs and key cost contributors associated with AL in a single Italian center.

RESEARCH DESIGN AND METHODS

Electronic records for adults who had undergone colorectal surgery with anastomosis (January 2015 - December 2016), were retrospectively reviewed. Patients with AL were identified using clinical signs and/or imaging findings and/or intraoperative findings. Available data included patient, clinical, and procedural characteristics, healthcare resource utilization, and inpatient costs. Multivariate models were used to adjust for potential confounders.

RESULTS

AL occurred in 12.3% of patients (N = 317). Mean adjusted inpatient cost was 108% higher (p < 0.001) for patients with AL versus no AL (€14,711; 95% CI: 12,113; 17,866 versus €7,089; 95% CI: 6,623; 7,587). Key cost contributors were ward stay, disposables, operating room, and hospital consultations. Mean losses (reimbursement minus costs) were €2,041/patient with AL. AL extended mean length of stay by 9 days and increased odds of reoperation and ICU stay (all p < 0.001).

CONCLUSIONS

Patients with AL place considerable economic and resource burden on healthcare systems and hospital reimbursement rates do not cover treatment costs. This study highlights an unmet need for novel techniques to reduce the burden of AL.

An umbrella systematic review of drain fluid analysis in colorectal surgery for the detection of anastomotic leak: Not yet ready to translate research studies into clinical practice

AIM

Anastomotic leak (AL) is the most important complication of intestinal surgery with an anastomosis. Whilst a number of studies have defined risk factors for AL, frustratingly, low-risk patients still develop AL. Studies have looked at drain fluid analysis for detection of AL, but these findings have failed to translate into routine clinical practice. This umbrella systematic review aims to provide an overview of the promising candidate biomarkers (BMs) that show potential to translate into clinical practice.

METHODS

A systematic literature search was conducted in MEDLINE, EMBASE, and the Cochrane, KSR Evidence and the Epistemonikos databases on the 14 April 2021. Only systematic reviews of cohort or controlled studies measuring drain fluid biomarkers in humans were included. The methodological quality of the reviews was assessed using the AMSTAR 2 instrument. Clinical trial registries were searched for trials actively investigating drain fluid BMs. Candidate BMs were classified, and threshold values investigated.

RESULTS

Nine systematic reviews, published between 2007 and 2020, met the inclusion criteria, and contained a total of 36 cohort studies. A total of 38 different BMs were studied. The most promising category of drain fluid BM was the extravasated intra-luminal substances (EILS) and five registered trials of these BMs were found. Two of nine reviews were of moderate quality.

CONCLUSIONS

The majority of BMs show inconsistent threshold values and are in the experimental stage. A number are not readily available for adoption into routine clinical practice. Most do not state a cut-off value to be considered as diagnostic.

Defunctioning stomas may reduce chances of a stoma-free outcome after anterior resection for rectal cancer

AIM

To investigate the conflicting consequences of faecal diversion on stoma outcomes and anastomotic leakage in anterior resection for rectal cancer, including interaction effects determined by the extent of mesorectal excision.

METHOD

Anterior resections between 2007 and 2016 were identified using the Swedish Colorectal Cancer Registry. National Patient Registry data were added to determine stoma outcome 2 years after surgery. Tumour distance from the anal verge constituted a proxy for extent of mesorectal excision [total mesorectal excision (TME): ≤10 cm; partial mesorectal excision (PME): 13-15 cm]. With confounder-adjusted probit regression, the total effect of defunctioning stoma on permanent stoma, and the interaction effect of extent of mesorectal excision, were estimated together with the indirect effect through anastomotic leakage. Baseline risks, risk differences (RDs) and relative risks (RRs) were reported.

RESULTS

The main study cohort included 4529 patients. Defunctioning stomas influenced the absolute permanent stoma risk (TME: RD 0.11 [95% CI 0.09-0.13]; PME: RD 0.15 [95% CI 0.13-0.16]). The baseline risk was higher in TME, with a resulting greater RR in PME (2.23 [95% CI 1.43-3.02] vs 4.36 [95% CI 3.05-5.68]). The indirect reduction in permanent stoma rates, due to the alleviating effect of faecal diversion on anastomotic leakage, was small (TME: 0.89 [95% CI 0.81-0.96]; PME: 0.96 [95% CI 0.91-1.00]).

CONCLUSION

In anterior resection for rectal cancer, defunctioning stomas may reduce chances of a stoma-free outcome. Considering leakage reduction benefits, consequences of routine diversion in TME might be fairly balanced, while this seems questionable in PME.

Perioperative intrapelvic hyaluronate application as prophylaxis against complications following rectal anastomotic dehiscence: An experimental study

PURPOSE

The aim of this experimental study was to test the method of prevention of postoperative complications, especially infectious, in partial dehiscence following stapler anastomosis in rectal surgeries.

METHODS

The method includes the application of a hyaluronic acid-based gel in combination with triclosan, which has antibacterial properties. The gel was applied to the space around the rectum with an artificial, precisely defined dehiscence so that the dehiscence was separated from the rest of pelvis and the peritoneal cavity to avoid the spread of infection. The study included 30 female pigs. The rectosigmoid colon was mobilized and transected completely. Anastomosis was constructed with circular staplers. A perforator was then used to create precisely defined artificial dehiscence. Subsequently the lesser pelvis was filled with hyaluronic gel such that the site of artificial dehiscence was covered completely.

RESULTS

All animals survived for 14 days until the second-look revision with no signs of failure in the anastomosis healing, local inflammation, and sepsis or postoperative complications, such as chills, refusal of liquid or feed, abdominal distension, and bowel obstruction.

CONCLUSION

Hyaluronic acid applied as a precursor solution around the rectal anastomosis fills the lesser pelvis perfectly. It prevents the leakage of intestinal contents in the lesser pelvis. Triclosan as an antibacterial substance prevents the spread of inflammation in the pelvis or even in the abdominal cavity.

A US Rectal Cancer Consortium Study of Inferior Mesenteric Artery Versus Superior Rectal Artery Ligation: How High Do We Need to Go?

BACKGROUND

The optimal level of pedicle ligation during proctectomy for rectal cancer, either at the origin of the inferior mesenteric artery or the superior rectal artery, is still debated.

OBJECTIVE

The objective was to determine whether superior rectal artery ligation portends equivalent technical or oncologic outcomes.

DESIGN

This was a retrospective analysis of a rectal cancer database (2007-2017).

SETTINGS

The study was conducted at 6 tertiary referral centers in the United States (Emory University, University of Michigan, University of Pittsburgh Medical Center, The Ohio State University Wexner Medical Center, Vanderbilt University Medical Center, and Washington University School of Medicine in St. Louis).

PATIENTS

Patients with primary, nonmetastatic rectal cancer who underwent low anterior resection or abdominoperineal resection were included.

MAIN OUTCOME MEASURES

Anastomotic leak, lymph node harvest, locoregional recurrence-free survival, recurrence-free survival, and overall survival were measured.

RESULTS

Of 877 patients, 86% (n = 755) received an inferior mesenteric artery ligation, whereas 14% (n = 122) received a superior rectal artery ligation. A total of 12%, 33%, 24%, and 31% were pathologic stage 0, I, II, and III. Median follow-up was 31 months. Superior rectal artery ligation was associated with a similar anastomotic leak rate compared with inferior mesenteric artery ligation (9% vs 8%; p = 1.0). The median number of lymph nodes removed was identical (15 vs 15; p = 0.38). On multivariable analysis accounting for relevant clinicopathologic factors, superior rectal artery ligation was not associated with increased anastomotic leak rate, worse lymph node harvest, or worse locoregional recurrence-free survival, recurrence-free survival, or overall survival (all p values >0.1).

LIMITATIONS

This was a retrospective design.

CONCLUSIONS

Compared with inferior mesenteric artery ligation, superior rectal artery ligation is not associated with either worse technical or oncologic outcomes. Given the potential risks of inadequate blood flow to the proximal limb of the anastomosis and autonomic nerve injury, we advocate for increased use of superior rectal artery ligation. See Video Abstract at http://links.lww.com/DCR/B646.

ESTUDIO DEL CONSORCIO DE CNCER DE RECTO DE ESTADOS UNIDOS DE LIGADURA BAJA DE LA ARTERIA MESENTRICA INFERIOR CONTRA LIGADURA ALTA DE LA ARTERIA MESENTRICA INFERIOR QU TAN ALTO DEBEMOS EXTENDERNOS

ANTECEDENTES:el nivel óptimo de la ligadura del pedículo en la proctectomía para el cáncer de recto, ya sea en el origen de la arteria mesentérica inferior o en la arteria rectal superior aún no esta definido.OBJETIVO:El objetivo era determinar si la ligadura de la arteria rectal superior pronostica resultados técnicos u oncológicos similares.DISEÑO:Análisis retrospectivo de una base de datos de cáncer de recto (2007-2017).ESCENARIO:el estudio se realizó en seis centros de referencia de tercer nivel en los Estados Unidos (Universidad de Emory, Universidad de Michigan, Centro médico de la Universidad de Pittsburgh, Centro médico Wexner de la Universidad Estatal de Ohio, Centro médico de la Universidad de Vanderbilt y Escuela de Medicina de la Universidad de Washington en St. Louis).PACIENTES:Se incluyeron pacientes con cáncer de recto primario no metastásico que se sometieron a resección anterior baja o resección abdominoperineal.PRINCIPALES VARIABLES ANALIZADAS:Se midió la fuga anastomótica, los ganglios linfáticos recuperados, la sobrevida sin recidiva locorregional, la sobrevida sin recidiva y la sobrevida global.RESULTADOS:De 877 pacientes, en el 86% (n = 755) se realizó una ligadura de la arteria mesentérica inferior, y en el 14% (n = 122) se realizó una ligadura de la arteria rectal superior. El 12%, 33%, 24% y 31% estaban en estadio patológico 0, I, II y III respectivamente. La mediana de seguimiento fue de 31 meses. La ligadura de la arteria rectal superior se asoció con una tasa de fuga anastomótica similar a la ligadura de la arteria mesentérica inferior (9 vs 8%, p = 1,0). La mediana del número de ganglios linfáticos extirpados fue idéntica (15 contra 15, p = 0,38). En el análisis multivariado que tiene en cuenta los factores clínico-patológicos relevantes, la ligadura de la arteria rectal superior no se asoció con una mayor tasa de fuga anastomótica, una peor cosecha de ganglios linfáticos o una peor sobrevida libre de recurrencia locorregional, sobrevida libre de recurrencia o sobrevida global (todos p> 0,1).LIMITACIONES:Diseño retrospectivo.CONCLUSIONES:En comparación con la ligadura de la arteria mesentérica inferior, la ligadura de la arteria rectal superior no se asocia a peores resultados técnicos ni oncológicos. Debido a los riesgos potenciales de un flujo sanguíneo inadecuado del muñon proximal de la anastomosis y la lesión de los nervios autonómicos, proponemos una mayor realización de la ligadura de la arteria rectal superior. Consulte Video Resumen en http://links.lww.com/DCR/B646.

"Early" Reoperation to Treat Complications Following Laparoscopic Colorectal Surgery: The Sooner the Better

BACKGROUND

Some postoperative complications after laparoscopic colorectal surgery (LCS) require reoperation to be treated. However, if the timing to perform this reoperation has some influence on outcome remains elusive. The aim of this study was to analyze if the timing to perform the reoperation has some influence in postoperative outcomes.

METHODS

A retrospective analysis of patients undergoing LCS and required a reoperation during the period 2000 to 2019 were included. The cohort was divided into 2 groups: early reoperation (ER): ≤48 hours or delayed reoperation (DR): ≥48 hours based on the interval between the suspicion of a complication and reoperation. Demographics, operative variables, and postoperative outcomes were compared between groups.

RESULTS

A total of 1843 LCS were performed, 68 (43%) were included in ER and 91 (57%) in DR. A computed tomography scan was less frequently performed in the ER (ER: 45% vs. DR: 70%; P=0.001). The rates of re-laparoscopy (ER: 86% vs. 73%; P=0.04) and negative findings in the reoperation (ER: 13% vs. DR: 1%, P=0.001) were higher in ER. There were no statistically significant differences in overall major morbidity (ER: 9% vs. DR: 21%; P=0.06) and mortality rate (ER: 4% vs. DR: 8.7%; P=0.28) between groups. The need of intensive care unit was significantly higher and the length of stay longer for patients in the DR group.

CONCLUSIONS

Despite a greater risk of negative findings, ER within 48 hours after the suspicion of a complication after a LCS offers higher chances of using a laparoscopic approach and it could probably provide better postoperative outcomes.

Optimization of indocyanine green angiography for colon perfusion during laparoscopic colorectal surgery

AIM

This study aims to evaluate the extrinsic effects of conditional factors affecting quantitative parameters and to establish the optimization of indocyanine green (ICG) angiography using in vitro experiments and a prospective observational study.

METHOD

In vitro experiments were performed to evaluate the correlation between conditional factors such as camera distance, surrounding lighting, fluorescence emission sources and ICG doses. The fluorescence intensity was measured from the ICG-containing test tube in each condition. In the clinical study, ICG angiography was applied to patients with colorectal cancer (n = 164). The quantitative perfusion parameters were the maximal fluorescence intensity (F_MAX ), slope, T_1/2MAX and perfusion time ratio (TR). Camera position, distance to colon, fluorescence emission source, surrounding lighting, site of angiography and ICG specific mode were considered as conditional factors and compared with the quantitative parameters to identify the optimal condition of ICG angiography.

RESULTS

The fluorescence intensity had an inverse correlation with distance, and the transitional zone was shown at a distance of 4-5 cm by slope differential. F_MAX , T_1/2MAX and slope were affected significantly by camera distance, site of angiography, fluorescence emission source and ICG mode as conditional factors. On multivariate analysis, F_MAX was independently associated with spectral ICG mode with red inversion, laser mode and camera distance. Conversely, TR was not related to any conditional factors.

CONCLUSION

Since quantitative parameters of ICG angiography are influenced by various conditions, a standardized protocol is required. The application of ICG specific modes with a constant distance of 4-5 cm can provide optimized fluorescence images.

SSAT State-of-the-Art Conference: Advancements in the Microbiome

The microbiome plays a major role in human physiology by influencing obesity, inducing inflammation, and impacting cancer therapies. During the 60th Annual Meeting of the Society of the Alimentary Tract (SSAT) at the State-of-the-Art Conference, experts in the field discussed the influence of the microbiome. This paper is a summary of the influence of the microbiome on obesity, inflammatory bowel disease, pancreatic cancer, cancer therapies, and gastrointestinal optimization. This review shows how the microbiome plays an important role in the development of diseases and surgical complications. Future studies are needed in targeting the gut microbiome to develop individualized therapies.

Predictive and Diagnostic Biomarkers of Anastomotic Leakage: A Precision Medicine Approach for Colorectal Cancer Patients

Development of an anastomotic leak (AL) following intestinal surgery for the treatment of colorectal cancers is a life-threatening complication. Failure of the anastomosis to heal correctly can lead to contamination of the abdomen with intestinal contents and the development of peritonitis. The additional care that these patients require is associated with longer hospitalisation stays and increased economic costs. Patients also have higher morbidity and mortality rates and poorer oncological prognosis. Unfortunately, current practices for AL diagnosis are non-specific, which may delay diagnosis and have a negative impact on patient outcome. To overcome these issues, research is continuing to identify AL diagnostic or predictive biomarkers. In this review, we highlight promising candidate biomarkers including ischaemic metabolites, inflammatory markers and bacteria. Although research has focused on the use of blood or peritoneal fluid samples, we describe the use of implantable medical devices that have been designed to measure biomarkers in peri-anastomotic tissue. Biomarkers that can be used in conjunction with clinical status, routine haematological and biochemical analysis and imaging have the potential to help to deliver a precision medicine package that could significantly enhance a patient's post-operative care and improve outcomes. Although no AL biomarker has yet been validated in large-scale clinical trials, there is confidence that personalised medicine, through biomarker analysis, could be realised for colorectal cancer intestinal resection and anastomosis patients in the years to come.

Dynamic Serosal Perfusion Assessment during Colorectal Resection Using Visible Light Spectroscopy

INTRODUCTION

Anastomotic leakage (AL) in colorectal surgery occurs with an incidence of up to 20%. Bowel perfusion is deemed to be one of the most important factors for anastomotic healing. However, not much is known about its variability during colorectal surgery and its impact on the outcome. Therefore, this study aims to evaluate serosal oxygen saturation patterns during colorectal resections with visible light spectroscopy (VLS).

MATERIALS AND METHODS

Bowel perfusion in patients undergoing left-sided colorectal resections was assessed at different timepoints during surgery using VLS on the colonic serosa. The primary outcome parameter was serosal oxygen saturation (StO2) at the anastomosis during different timepoints of surgery.

RESULTS

We included 50 patients who underwent colorectal resection for bowel cancer (58%) and diverticular disease (34%). StO2 at the proximal site of the anastomosis increased significantly throughout the surgery (mean difference 3.61%; 95% CI -6.22 to -1.00; p = 0.008). However, aberrancy from this identified perfusion pattern had no impact on the postoperative outcome.

CONCLUSION

During colorectal resections, we could demonstrate an increase of the colonic StO2 throughout surgery. Appearance of AL was not associated with lower StO2, underlining the multifactorial genesis of developing AL.

Does intraoperative flexible endoscopy offer any benefit compared to conventional air leak testing after circular stapled left-sided laparoscopic colon surgery?

BACKGROUND

Anastomotic leakage is still a feared complication after left-sided colonic resections. Various types of "anastomotic leak testing methods" are described in current literature. In this study we evaluated the use of intraoperative flexible endoscopy in comparison to conventional air leak testing after performing a circular stapled anastomosis in left-sided laparoscopic colon surgery.

METHODS

A retrospective database consisting of 130 patients with left sided colonic resections between 01/2015 and 12/2019 at our hospital was evaluated. After performing a circular stapled anastomosis flexible endoscopy was done in 69 cases, 61 patients were controlled with a conventional air leak test. Intraoperative and postoperative complications were recorded and retrospectively evaluated.

RESULTS

In the flexible endoscopy group, we observed complications in 13,04%, in the conventional air leak testing group in 9,83%. Postoperative anastomotic leakage was observed in 10,14% in the flexible endoscopy group and 4,91% in the conventional air leak test group. In 10,14% a positive air leak test was seen in the flexible endoscopy group and 11,47% in the conventional air leak testing group. In those cases, we observed no postoperative complications in the first group, in the conventional group we had two anastomotic leakages and one infected haematoma.

CONCLUSIONS

In the case of a positive air leak, flexible endoscopy offered a more exact detection of the leak. In those cases, no anastomotic leakage was observed postoperatively. In our opinion, flexible endoscopy should be recommended for testing the anastomosis intraoperatively in every left-sided colon surgery.

Sepsis after elective surgery - Incidence, aetiology and outcome

BACKGROUND

Sepsis requiring admission to intensive care (ICU) is a rare complication of elective surgery, but is associated with high morbidity and mortality. The aim of this study was to describe the incidence and outcome of sepsis following elective surgery.

METHODS

This was a retrospective, observational study where all admissions to Icelandic ICUs during calendar years 2006, 2008, 2010, 2012, 2014 and 2016 were screened, identifing patients with sepsis following elective surgery (ACCP/SCCM criteria). The number of elective operations performed at the largest center (Landspitali) during the study years were collected. Descriptive statistics were used to assess the incidence and outcome of patients with sepsis after elective surgery.

RESULTS

During the study years, 88 patients were admitted to Icelandic ICUs with sepsis following elective surgery. Of those, 80 were operated at Landspitali, where the incidence of sepsis was 0.19% per elective procedure, highest following pancreaticoduodenectomies (14%, CI 6-25) and esophagectomies (13%, CI 4-27), but the greatest number of patients (30% (26/88)) developed sepsis after a colorectal procedure. The most common infection sources were the abdomen (65% (57/88)) and lungs/mediastinum (22% (19/88)), frequently polymicrobial (58% (36/62) of patients with cultures). The incidence of insufficient empirical antibiotics was high (50% (30/60)). The median ICU and hospital length-of-stay were 5.5 and 26 days and the 28-day and 1-year mortality rates were 16% (14/88) and 41% (36/87), respectively.

CONCLUSIONS

Incidence of sepsis following elective surgery is low in Iceland but mortality is high. Initial antimicrobial therapy needs careful consideration in these hospital-acquired, often polymicrobial infections.

Effects of Sevoflurane Inhalation Anesthesia on the Intestinal Microbiome in Mice

In recent years, more and more attention has been paid to intestinal microbiome. Almost all operations will go through the anesthesia process, but it is not clear whether the intervention of anesthesia alone will affect the change in the intestinal microbiome. The purpose of this study was to verify the effect of sevoflurane inhalation anesthesia on the intestinal microbiome. The animal in the experimental group was used to provide sevoflurane inhalation anesthesia for 4 hours. The control group was not intervened. The feces of the experimental group and the control group were collected on the 1st, 3rd, 7th and 14th days after anesthesia. Sevoflurane inhalation anesthesia will cause changes in the intestinal microbiome of mice. It appears on the 1st day after anesthesia and is most obvious on the 7th day. The specific manifestation is that the abundance of microbiome and the diversity of the microbiome is reduced. At the same time, Untargeted metabonomics showed that compared with the control group, the experimental group had more increased metabolites related to the different microbiome, among which 5-methylthioadenosine was related to the central nervous system. Subsequently, the intestinal microbiome diversity of mice showed a trend of recovery on the 14th day. At the genus level, the fecal samples obtained on the 14th day after anesthesia exhibited significantly increased abundances of Bacteroides, Alloprevotella, and Akkermansia and significantly decreased abundances of Lactobacillus compared with the samples obtained on the 1st day after anesthesia. However, the abundance of differential bacteria did not recover with the changing trend of diversity. Therefore, we believe that sevoflurane inhalation anesthesia is associated with changes in the internal microbiome and metabolites, and this change may be completed through the brain-gut axis, while sevoflurane inhalation anesthesia may change the intestinal microbiome for as long as 14 days or longer.

Human fibrinogen and thrombin patch for extraluminal protection of intestinal anastomosis

In spite of recent advances regarding equipment and surgical techniques in colorectal surgery, rates of anastomotic dehiscence (AD) have remained stable throughout the years. The development of products to protect anastomosis aiming the reduction of AD rates has shown to be promising. Human fibrinogen and thrombin patch (HFTP Tachosil®) have been used in experimental studies in animals and small case series in humans, with promising results. In this study, the authors describe the technique of HFTP use in details, aiming the protection of colorectal anastomosis, and retrospectively demonstrate the preliminary results in a pilot case series. HFTP was used in 4 patients submitted to conventional surgery. The procedures performed were: left colon resection, segmental colectomy (both for colorectal cancer), enteral anastomosis for fistula closure and right ileocolectomy. Anastomotic healing and absence of complications were observed in 3 patients, and the patient submitted to right ileocolectomy developed AD and died after reoperation. The use of HFTP is safe and can be indicated in selected cases. However, AD can occur even after the use of this strategy. Randomized controlled trials with larger samples of patients are needed in order to properly define the real benefits of this strategy in dehiscence prevention

Indocyanine green perfusion assessment of the gastric conduit in minimally invasive Ivor Lewis esophagectomy

BACKGROUND

Anastomotic leak is a serious complication following esophagectomy. The aim of the study was to report our experience with indocyanine green fluorescence angiography (ICG-FA)-PINPOINT® assisted minimally invasive Ivor Lewis esophagectomy (MILE) and assess factors associated with anastomotic leak.

METHODS

We reviewed consecutive patients undergoing MILE from 2013 to 2018. Intraoperative real-time assessment of gastric conduit was performed using ICG-FA with PINPOINT®. Perfusion was categorized as good perfusion (brisk ICG visualization to conduit tip) or non-perfusion (any demarcation along the conduit).

RESULTS

100 patients (81 males, median age 68 [60-72]) underwent MILE for malignancy in 96 patients and benign disease in 4 patients. There were six anastomotic leaks all managed with endoscopic stent placement. There was no intraoperative mortality and no 30-day mortality in leak patients. Patients with a leak were more likely to be overweight with BMI > 25 (100% versus 53%, p = 0.03), have pre-existing diabetes (50% versus 13%, p = 0.04), and have higher intraoperative estimated blood loss (260 mL [95-463] versus 75 mL [48-150], p = 0.03). Anastomotic leaks occurred more frequently in the non-perfusion (67%) versus the good perfusion category (33%, p = 0.03). By multivariable analysis, diabetes (odds ratio [OR] 6.42; p = 0.04) and non-perfusion (OR 6.60; p = 0.04) were independently associated with leak.

CONCLUSION

Intraoperative use of ICG-FA may be a useful adjunct to assess perfusion of the gastric conduit with non-perfusion being independently associated with a leak. While perfusion plays an important role in anastomotic integrity, development of a leak is multifactorial, and ICG-FA should be used in conjunction with the optimization of patient and procedural components to minimize leak rates. Prospective, randomized studies are required to validate the interpretation, efficacy, and application of this novel technology in minimally invasive esophagectomies.

Effects of Warmed and Humidified CO2 Surgical Site Insufflation in a Novel Experimental Model of Magnetic Compression Colonic Anastomosis

Background. Pneumoperitoneum insufflation with warmed and humidified carbon dioxide (WH-CO2) can prevent heat loss and increase tissue oxygenation. We evaluated the impact of localized WH-CO2 insufflation on the anastomotic healing process. Methods. Sixty male Wistar rats were randomized: Group 1 (control, n = 12), Group 2 (cold and dry CO2, CD-CO2, n = 24), and Group 3 (WH-CO2, n = 24). A magnetic compression side-to-side colonic anastomosis was performed under 60-minute local abdominal CO2 flow insufflation. Animal temperature was recorded. IL-1, IL-6, and CRP levels were assessed before and after insufflation and on postoperative day (POD) 7 and POD 10. Endoscopic follow-up was performed on POD 7 and POD 10. A burst pressure (BP) test of the specimen was performed on POD 10, and histopathological analysis was then performed. Metabolomics of the anastomotic site was determined. Results. Seven rats (5 CD-CO2 group, 1 WH-CO2 group, and 1 control group) died during the survival period. Necropsies revealed intestinal occlusions (n = 2). One additional rat from the CD-CO2 group was sacrificed on POD 7 due to intestinal perforation. The postoperative course was uneventful in the remaining cases. There was no difference in BP among the groups. Thermal monitoring confirmed that WH-CO2 insufflation was effective to reduce heat loss. IL-1 levels were statistically and significantly lower on POD 10 in the WH-CO2 group than the CD-CO2 group but not lower than the control group. CRP levels, histopathology, and metabolomics did not show any difference between the 3 groups. Conclusions. WH-CO2 was effective to preserve core temperature. However, it did not improve anastomotic healing.