Systematic review of methods to predict and detect anastomotic leakage in colorectal surgery

Drainage Fluid Amylase as a Biomarker for the Detection of Anastomotic Leakage After Low Anterior Resection of Rectal Cancer: A Two-center Study

Aim

This study aimed to investigate the utility of measuring amylase levels in drainage fluid (DFA) for early, non-invasive detection of anastomotic leakage (AL) in undergoing low anterior resection (LAR) for rectal cancer.

Patients and Methods

This prospective observational cohort study analyzed drainage fluid samples from patients who underwent LAR for rectal cancer at two medical centers between February 2021 and December 2023. DFA levels were measured on postoperative days (PODs) 1, 3, and 5. AL was confirmed by clinical evidence and radiological imaging. Statistical analyses were performed to evaluate the diagnostic performance of DFA.

Results

Of 120 LAR cases, AL occurred in five (4.16%). DFA levels on POD 3 and 5 were significantly higher in the AL than in the non-AL group (p<0.0001). DFA on POD 5 had the highest diagnostic accuracy for early AL detection, with an area under the curve of 0.99, achieving 100% sensitivity and 99.5% specificity at a cutoff of 846 U/l. A DFA >846 U/l predicted AL with negative predictive and positive predictive values of 83.3% and 100%, respectively, on POD 5.

Conclusion

Measuring DFA is a non-invasive, simple and cost-effective method for early AL detection in patients with rectal cancer undergoing LAR. Our findings also suggested that drain placement may be useful for the early detection of AL through DFA measurement.

Diagnostic Modalities for Early Detection of Anastomotic Leak After Colorectal Surgery

INTRODUCTION

Anastomotic leak (AL) remains a severe complication following colorectal surgery, leading to increased morbidity and mortality, particularly in cases of delayed diagnosis. Existing diagnostic methods, including computed tomography (CT) scans, contrast enemas, endoscopic examinations, and reoperations can confirm AL but lack strong predictive value. Early detection is crucial for improving patient outcomes, yet a definitive and reliable predictive test, or "gold standard," is still lacking.

METHODS

A comprehensive PubMed review was focused on CT imaging, serum levels of C-reactive protein (CRP), and procalcitonin (PCT) to assess their predictive utility in detecting AL after colorectal resection. Three independent reviewers evaluated eligibility, extracted data, and assessed the methodological quality of the studies.

RESULTS

Summarized in detailed tables, our analysis revealed the effectiveness of both CRP and PCT in the early detection of AL during the postoperative period. CT imaging, capable of identifying fluid collection, pneumoperitoneum, extraluminal contrast extravasation, abscess formation, and other early signs of leak, also proved valuable.

CONCLUSIONS

Considering the variability in findings and statistics across these modalities, our study suggests a personalized, multimodal approach to predicting AL. Integrating CRP and PCT assessments with the diagnostic capabilities of CT imaging provides a nuanced, patient-specific strategy that significantly enhances early detection and management. By tailoring interventions based on individual clinical characteristics, surgeons can optimize patient outcomes, reduce morbidity, and mitigate the consequences associated with AL after colorectal surgery. This approach emphasizes the importance of personalized medicine in surgical care, paving the way for improved patient health outcomes.

Developments in the Use of Indocyanine Green (ICG) Fluorescence in Colorectal Surgery

Indocyanine Green (ICG) has significantly advanced minimally invasive surgery. It is widely recognized for its ability to visualize blood vessel patency in real-time across various surgical specialties. While its primary use in colorectal surgery is to evaluate anastomoses for leaks, numerous other applications have been documented in the literature. In this review, we aim to explore both established and emerging applications of ICG fluorescence in colorectal surgery, with the goal of improving patient outcomes. This includes preoperative tumor marking and the detection of metastatic disease. Some applications, such as lymphatic mapping, require further research to determine their impact on clinical practices. Conversely, others, like the intraoperative localizations of ureters, necessitate additional procedures and are not yet widely accepted by the surgical community. However, the development of alternative compounds could offer better solutions. Future research should focus on areas like quantitative ICG and protocol standardization in prospective multicenter studies.

Drainage fluid LDH and neutrophil to lymphocyte ratio as biomarkers for early detecting anastomotic leakage in patients undergoing colorectal surgery

OBJECTIVES

In this study, we investigated the role of several circulating and drainage fluid biomarkers for detecting postoperative complications (PCs) and anastomotic leakage (AL) in patients undergoing colorectal surgery.

METHODS

All consecutive patients undergoing colorectal surgery between June 2018 and April 2020 were prospectively considered. On postoperative days (POD) 1, 3, and 5, we measured lactate dehydrogenase (LDH) in drainage fluid, C-reactive protein (CRP) in serum and drainage fluid, and neutrophil to lymphocyte ratio (NLR).

RESULTS

We enrolled 187 patients. POD1 patients with AL had higher serum CRP levels, while on POD3 and on POD5 higher NLR and serum CRP. LDH and CRP in drainage fluid were also significantly higher at both time points. The area under the curves (AUCs) of serum and drainage fluid CRP were 0.752 (0.629-0.875) and 0.752 (0.565-0.939), respectively. The best cut-off for serum and drainage fluid CRP was 185.23 and 76 mg/dL, respectively. The AUC of NLR on POD3 was 0.762 (0.662-0.882) with a sensitivity and specificity of 84 and 63 %, respectively, at a cut-off of 6,6. Finally, drainage fluid LDH showed the best diagnostic performance for AL, with an AUC, sensitivity, and specificity of 0.921 (0.849-0.993), 82 %, and 90 % at a cut-off of 2,186 U/L. Trends in serum parameters between patients with or without PCs or AL were also evaluated. Interestingly, we found that NLR decreased faster in patients without PCs than in patients with PCs and patients with AL.

CONCLUSIONS

Drainage fluid LDH and NLR could be promising biomarkers of PCs and AL.

Circulating metabolic markers after surgery identify patients at risk for severe postoperative complications: a prospective cohort study in colorectal cancer

BACKGROUND

Early detection of postoperative complications after colorectal cancer (CRC) surgery is associated with improved outcomes. The aim was to investigate early metabolomics signatures capable to detect patients at risk for severe postoperative complications after CRC surgery.

MATERIALS AND METHODS

Prospective cohort study of patients undergoing CRC surgery from 2015 to 2018. Plasma samples were collected before and after surgery, and analyzed by mass spectrometry obtaining 188 metabolites and 21 ratios. Postoperative complications were registered with Clavien-Dindo Classification and Comprehensive Complication Index.

RESULTS

One hundred forty-six patients were included. Surgery substantially modified metabolome and metabolic changes after surgery were quantitatively associated with the severity of postoperative complications. The strongest positive relationship with both Clavien-Dindo and Comprehensive Complication Index (β=4.09 and 63.05, P <0.001) corresponded to kynurenine/tryptophan, against an inverse relationship with lysophosphatidylcholines (LPCs) and phosphatidylcholines (PCs). Patients with LPC18:2/PCa36:2 below the cut-off 0.084 µM/µM resulted in a sevenfold higher risk of major complications (OR=7.38, 95% CI: 2.82-21.25, P <0.001), while kynurenine/tryptophan above 0.067 µM/µM a ninefold (OR=9.35, 95% CI: 3.03-32.66, P <0.001). Hexadecanoylcarnitine below 0.093 µM displayed a 12-fold higher risk of anastomotic leakage-related complications (OR=11.99, 95% CI: 2.62-80.79, P =0.004).

CONCLUSION

Surgery-induced phospholipids and amino acid dysregulation is associated with the severity of postoperative complications after CRC surgery, including anastomotic leakage-related outcomes. The authors provide quantitative insight on metabolic markers, measuring vulnerability to postoperative morbidity that might help guide early decision-making and improve surgical outcomes.

Tube Stoma for the Management of Ileocolic Anastomotic Leak in a Patient With Metastatic Colon Cancer

This case involves a 53-year-old male who was diagnosed with stenotic ascending colon cancer and peritoneal metastatic deposits. He was initially planned for cytoreductive surgery and heated intraperitoneal chemotherapy (CRS and HIPEC), along with resection of the primary tumor in the form of right hemicolectomy. Intraoperatively, the disease was found to be more extensive than anticipated. Consequently, the plan was modified to include debulking right hemicolectomy with hand-sewn ileocolic anastomosis and extensive peritoneal procedures. Postoperatively, he experienced an anastomotic leak, leading to another laparotomy. However, due to anatomical challenges, creating a stoma was considered unsafe. Therefore, innovative interventions were performed, including controlling the anastomotic defect with a 30Fr Foley catheter without disrupting the anastomosis. A collaborative effort from various medical teams facilitated the patient's discharge home after an extended stay in the critical care unit (CCU).

Application of metagenomic sequencing of drainage fluid in rapid and accurate diagnosis of postoperative intra-abdominal infection: a diagnostic study

BACKGROUND

Postoperative intra-abdominal infection (PIAI) is one of the most serious complications of abdominal surgery, increasing the risk of postoperative morbidity and mortality and prolonging hospital stay. Rapid diagnosis of PIAI is of great clinical value. Unfortunately, the current diagnostic methods of PIAI are not fast and accurate enough.

METHODS

The authors performed an exploratory study to establish a rapid and accurate diagnostic method of PIAI. The authors explored the turnaround time and accuracy of metagenomic next-generation sequencing (mNGS) in diagnosing PIAI. Patients who underwent elective abdominal surgery and routine abdominal drainage with suspected PIAI were enroled in the study. The fresh midstream abdominal drainage fluid was collected for mNGS and culturing.

RESULTS

The authors found that the median sample-to-answer turnaround time of mNGS was dramatically decreased than that of culture-based methods (<24 h vs. 59.5-111 h). The detection coverage of mNGS was much broader than culture-based methods. The authors found 26 species from 15 genera could only be detected by mNGS. The accuracy of mNGS was not inferior to culture-based methods in the 8 most common pathogens detected from abdominal drainage fluid (sensitivity ranged from 75 to 100%, specificity ranged from 83.3 to 100%, and kappa values were higher than 0.5). Moreover, the composition of the microbial spectrum established by mNGS varied between upper and lower gastrointestinal surgery, enhancing the understanding of PIAI pathogenesis.

CONCLUSION

This study preliminarily revealed the clinical value of mNGS in the rapid diagnosis of PIAI and provided a rationale for further research.

BIO-CXRNET: a robust multimodal stacking machine learning technique for mortality risk prediction of COVID-19 patients using chest X-ray images and clinical data

Nowadays, quick, and accurate diagnosis of COVID-19 is a pressing need. This study presents a multimodal system to meet this need. The presented system employs a machine learning module that learns the required knowledge from the datasets collected from 930 COVID-19 patients hospitalized in Italy during the first wave of COVID-19 (March-June 2020). The dataset consists of twenty-five biomarkers from electronic health record and Chest X-ray (CXR) images. It is found that the system can diagnose low- or high-risk patients with an accuracy, sensitivity, and F1-score of 89.03%, 90.44%, and 89.03%, respectively. The system exhibits 6% higher accuracy than the systems that employ either CXR images or biomarker data. In addition, the system can calculate the mortality risk of high-risk patients using multivariate logistic regression-based nomogram scoring technique. Interested physicians can use the presented system to predict the early mortality risks of COVID-19 patients using the web-link: Covid-severity-grading-AI. In this case, a physician needs to input the following information: CXR image file, Lactate Dehydrogenase (LDH), Oxygen Saturation (O2%), White Blood Cells Count, C-reactive protein, and Age. This way, this study contributes to the management of COVID-19 patients by predicting early mortality risk.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00521-023-08606-w.

Assessment of Colorectal Anastomosis with Intraoperative Colonoscopy: Its Role in Reducing Anastomotic Complications

The use of intraoperative colonoscopy (IOC) to evaluate the integrity of newly created anastomosis has been advocated by some surgeons. However, whether direct visualization of fresh anastomosis can help reduce anastomotic problems is still unclear. This study investigates the impact of immediate endoscopic assessment of colorectal anastomosis on anastomotic problems. This is a retrospective study conducted at a single center. Among six hundred forty-nine patients who underwent stapled anastomosis for left-sided colorectal cancer, the anastomotic complications were compared between patients who underwent IOC and those who did not. Additionally, patients with subsequent intervention after the IOC were compared to those without the intervention. Twenty-seven patients (5.0%) developed anastomotic leakage, and six (1.1%) experienced anastomotic bleeding postoperatively. Of the patients with IOC, 70 patients received reinforcement sutures to secure anastomotic stability. Of 70 patients, 39 patients showed abnormal findings in IOC. Thirty-seven patients (94.9%) who underwent reinforcement sutures did not develop postoperative anastomotic problems. This study demonstrates that IOC assessment with reinforcement sutures does not imminently reduce the rate of anastomotic complications. However, its use may play a role in detecting early technical failure and preventing postoperative anastomotic complications.

Is There a Role for Mechanical and Oral Antibiotic Bowel Preparation for Patients Undergoing Minimally Invasive Colorectal Surgery? A Systematic Review and Meta-analysis

INTRODUCTION

To date, all meta-analyses on oral antibiotic prophylaxis (OA) and mechanical bowel preparation (MBP) in colorectal surgery have included results of both open and minimally invasive approaches. Mixing both procedures may lead to false conclusions. The aim of the study was to assess the available evidence of mechanical and oral antibiotic bowel preparation in reducing the incidence of surgical site infection (SSI) and other complications following minimally invasive elective colorectal surgery.

METHODS

We searched PubMed, Science Direct, Google Scholar and Cochrane Library from 2000 to May 1, 2022. Comparative randomized and non-randomized studies were included. We reviewed the use of oral OA, MBP and combinations of these treatments. The methodological quality of the included studies was assessed using the Rob v2 and Robins-I tools.

RESULTS

We included 18 studies (7 randomized controlled trials and 11 cohort studies). Meta-analysis of the included studies showed that the combination of MBP + OA was associated with a significant reduction in SSI, AL and overall morbidity compared with the other options no preparation, MBP only and OA only.  CONCLUSION: Adding OA with MBP has a positive impact in reducing the incidence of SSI, AL and overall morbidity after minimally invasive colorectal surgery. Therefore, the combination of OA and MBP should be encouraged in this selected group of patients undergoing minimally invasive surgery.

Low-Dose CT Fluoroscopy-Guided Drainage of Deep Pelvic Fluid Collections after Colorectal Cancer Surgery: Technical Success, Clinical Outcome and Safety in 40 Patients

PURPOSE

To assess the technical (TS) and clinical success (CS) of CT fluoroscopy-guided drainage (CTD) in patients with symptomatic deep pelvic fluid collections following colorectal surgery.

METHODS

A retrospective analysis (years 2005 to 2020) comprised 43 drain placements in 40 patients undergoing low-dose (10-20 mA tube current) quick-check CTD using a percutaneous transgluteal (n = 39) or transperineal (n = 1) access. TS was defined as sufficient drainage of the fluid collection by ≥50% and the absence of complications according to the Cardiovascular and Interventional Radiological Society of Europe (CIRSE). CS comprised the marked reduction of elevated laboratory inflammation parameters by ≥50% under minimally invasive combination therapy (i.v. broad-spectrum antibiotics, drainage) within 30 days after intervention and no surgical revision related to the intervention required.

RESULTS

TS was gained in 93.0%. CS was obtained in 83.3% for C-reactive Protein and in 78.6% for Leukocytes. In five patients (12.5%), a reoperation due to an unfavorable clinical outcome was necessary. Total dose length product (DLP) tended to be lower in the second half of the observation period (median: years 2013 to 2020: 544.0 mGy*cm vs. years 2005 to 2012: 735.5 mGy*cm) and was significantly lower for the CT fluoroscopy part (median: years 2013 to 2020: 47.0 mGy*cm vs. years 2005 to 2012: 85.0 mGy*cm).

CONCLUSIONS

Given a minor proportion of patients requiring surgical revision due to anastomotic leakage, the CTD of deep pelvic fluid collections is safe and provides an excellent technical and clinical outcome. The reduction of radiation exposition over time can be achieved by both the ongoing development of CT technology and the increased level of interventional radiology (IR) expertise.

High amylase concentration in drainage liquid can early predict proximal and distal intestinal anastomotic leakages: A prospective observational study

Background

Anastomotic leak (AL) is a serious complication in digestive surgery. Early diagnosis might allow clinicians to anticipate appropriate management. The aim of this study was to assess the predictive value of amylase concentration in drain fluid for the early diagnosis of digestive tract AL.

Materials and Methods

Hundred and fourteen consecutive patients "at risk" of AL, in whom a flexible drainage was placed by surgeon's choice after digestive anastomosis were included. Patients with eso-gastric, bilio-digestive, and pancreatic anastomoses were excluded. Drain amylase measurement (DAM) was routinely performed on postoperative day (POD) 1, 3, 5-7. DAM values were compared between patients with postoperative AL versus patients without AL. A receiver-operating curve (ROC) with calculation of the areas under the ROC curves area under curves was performed and a cutoff value of DAM was calculated.

Results

AL occurred in 25 patients (AL group) and 89 patients did not present AL (C group). The mean DAM was significantly higher in AL group versus C Group on POD 1, 3, and 5. A cutoff value of 307 IU/L predicted the occurrence of AL with a sensitivity and specificity of 91% and 100%, respectively. Positive and negative predictive values were 100% and 97.5%, respectively. Patients with AL had an elevated DAM prior to the appearance of any clinical signs of AL.

Conclusion

High level DAM could accurately predict AL for proximal and distal digestive tract anastomoses. This simple, noninvasive, and low-cost method can accurately predict early AL and help physicians to perform appropriate imaging and treatment.

Bevacizumab increases the risk of anastomosis site leakage in metastatic colorectal cancer

Background

Bevacizumab is a humanized monoclonal antibody against vascular endothelial growth factor and is used in combination with first-line chemotherapy in the treatment of metastatic colorectal cancer. One of the side effects of bevacizumab is gastrointestinal perforation. This study was designed to identify the effect of bevacizumab in intestinal anastomosis site healing.

Methods

From January 2010 to December 2020, patients diagnosed with stage IV colorectal cancer treated with palliative chemotherapy or chemoradiotherapy followed by radical surgery were retrospectively reviewed. Clinical signs or symptoms and computed tomography were tools used for diagnosing anastomosis site leakage. The patients were divided into two groups, the bevacizumab group (n = 136) and the non-bevacizumab group (n = 124).

Results

Among the 260 patients 14 (5.4%) patients were diagnosed with anastomosis site leakage. In the bevacizumab group, 13 (9.6%) patients were diagnosed with anastomotic leakage. In the non-bevacizumab group, 1 (0.8%) patient was diagnosed with anastomotic leakage. Anastomosis site leakage was significantly higher in the bevacizumab treatment group (P < 0.001). In the bevacizumab group, period of drug discontinuation before surgery was factor associated with anastomosis site leakage in multivariable analysis (P = 0.031).

Conclusion

Stage IV colorectal patients treated with bevacizumab before radical surgery for primary cancer should be carefully observed of anastomosis site leakage after surgery, and the period of drug discontinuation before surgery should be longer than 5 weeks to avoid anastomosis site leakage.

An alternative asymmetric figure-of-eight single-layer suture technique for bowel anastomosis in an in vitro porcine model

Anastomotic techniques are of vital importance in restoring gastrointestinal continuity after resection. An alternative asymmetric figure-of-eight single-layer suture anastomotic technique was introduced and its effects were evaluated in an in vitro porcine model. Twelve 15-cm grossly healthy small intestine segments from a porcine cadaver were harvested and randomly divided into asymmetric figure-of-eight single-layer suture (figure-of-eight suture) and single-layer interrupted suture technique (interrupted suture) groups (n = 6 in each group). The anastomosed bowel was infused with methylene blue solution to test anastomotic leakage. Anastomosis construction time, leakage, and suture material cost were recorded and analyzed statistically using Fisher's exact test and Student's t-test. One anastomotic leakage occurred (16.67%) in the figure-of-eight suture group, and two (33.33%) in the interrupted suture group (p &gt; 0.9999). The anastomosis construction time was relatively short in the figure-of-eight suture group, but the difference did not reach a statistically significant level between the two groups. The mean number of suture knots and the cost of suture material in the figure-of-eight suture group were significantly decreased in comparison to the interrupted suture group (15.67 ± 3.30 vs. 22.17 ± 2.03, 167.11 ± 35.20 vs. 236.45 ± 21.70 CNY, p &lt; 0.01, respectively). Our results suggested that the alternative asymmetric figure-of-eight suture technique was safe and economic for intestinal anastomosis. An in vivo experiment is required to elucidate the effects of this suture technique on the physiological anastomotic healing process.

Endoscopic vacuum therapy and early surgical closure after pelvic anastomotic leak: meta-analysis of bowel continuity rates

BACKGROUND

Endoscopic vacuum therapy (EVT) with or without early surgical closure (ESC) is considered an effective option in the management of pelvic anastomotic leakage. This meta-analysis evaluated the effectiveness of EVT in terms of stoma reversal rate and the added value of ESC.

METHODS

A systematic search of PubMed, MEDLINE, and the Cochrane Library was conducted in November 2021 to identify articles on EVT in adult patients with pelvic anastomotic leakage. The primary outcome was restored continuity rate. Following PRISMA guidelines, a meta-analysis was undertaken using a random-effects model.

RESULTS

Twenty-nine studies were included, accounting for 827 patients with leakage who underwent EVT. There was large heterogeneity between studies in design and reported outcomes, and a high risk of bias. The overall weighted mean restored continuity rate was 66.8 (95 per cent c.i. 58.8 to 73.9) per cent. In patients undergoing EVT with ESC, the calculated restored continuity rate was 82 per cent (95 per cent c.i. 50.1 to 95.4) as compared to 64.7 per cent (95 per cent c.i. 55.7 to 72.7) after EVT without ESC. The mean number of sponge exchanges was 4 (95 per cent c.i. 2.7 to 4.6) and 9.8 (95 per cent c.i. 7.3 to 12.3), respectively. Sensitivity analysis showed a restored continuity rate of 81 per cent (95 per cent c.i. 55.8 to 99.5) for benign disease, 69.0 per cent (95 per cent c.i. 57.3 to 78.7) for colorectal cancer, and 65 per cent (95 per cent c.i. 48.8 to 79.1) if neoadjuvant radiotherapy was given.

CONCLUSION

EVT is associated with satisfactory stoma reversal rates that may be improved if it is combined with ESC.

Endoluminal vacuum-assisted therapy as a treatment for anastomotic leakage in colorectal surgery

Anastomotic leakage (AL) has a wide range of clinical features ranging from radiological only findings to peritonitis and sepsis with multiorgan failure. An early diagnosis of AL is essential in order to establish the most appropriate treatment for this complication. Despite AL continues to be a dreadful compli-cation after colorectal surgery, there has been no consensus on its management. However, based on patient’s presentation and timing of the AL, there has been a gradual shift to a more conservative management, keeping surgery as the last option Reoperation for sepsis control is rarely necessary especially in those patients who already have a diverting stoma at the time of the leak. A nonoperative management is usually preferred in these patients. There are several treatment options, also for patients without a stoma who do not require a reoperation for a contained pelvic leak, including recently developed endoscopic procedures, such as clip placement or endoluminal vacuum-assisted therapy. More conservative treatments could be an option in patients who are clinically stable or in presence of a small defect.

Routine postoperative CT to detect anastomotic leakage after low anterior resection for rectal cancer has a low sensitivity and specificity and a poor interobserver agreement

AIM

To compare the accuracy and interobserver variation of routine computed tomography (CT) on postoperative day 6-8 to detect anastomotic leakage (AL) verified by re-operation and/or endoscopy. A secondary objective was to identify the predictive values of different CT findings as an indicator for AL.

MATERIAL AND METHODS

The material for this study originates from two previous prospective multicentre studies including 277 patients who were scheduled for routine abdominal CT postoperative day 6-8. Inclusion criteria for the present study were routine CT without contrast medium followed by CT with rectal contrast medium. Two independent senior radiologists blinded to the clinical outcome reviewed the CT examinations for specific findings according to a predefined scheme.

RESULTS

A total of 52 patients fulfilled the inclusion criteria. AL occurred in 14 patients of which nine were clinical and five subclinical. The two radiologists diagnosed AL at unenhanced CT with sensitivities of 71.4% and 50%, respectively, and of 57.1% and 35.7% with rectal contrast medium. The corresponding specificities were 55.3% and 81.6%, and 94.7% and 92.1%. Peri-anastomotic free air and contrast medium leakage had the highest odds ratios for AL.

CONCLUSION

The diagnostic sensitivity and specificity of routine postoperative CT to detect AL after low anterior resection for rectal cancer is low and with considerable interobserver variation.

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.

A development study of drain fluid gastrografin as a biomarker of anastomotic leak

PURPOSE

Anastomotic leakage (AL) is the anathema of colorectal surgery. Its occurrence leads to increased morbidity and mortality and a prolonged hospital stay. Much work has gone into studying various biomarkers in drain fluid to facilitate early detection of AL. This stage 2a development study aims to assess the safety and feasibility of reliably detecting the iodine in Gastrografin (GG; Bayer Australia Ltd.) in drain fluid and stool samples by dual-energy computed tomography (DECT).

METHODS

This is a prospective, observational, controlled, consecutive cohort study establishing the safety and feasibility of the detection of GG in surgical drain fluid and stool as a biomarker of AL when patients with a low pelvic colorectal anastomosis undergo luminal flushing of the rectal tube with GG.

RESULTS

Ten consecutive patients were allocated to the saline flush group and the following 10 to the GG flush group. Three patients in the saline flush group developed an AL. One patient in the GG flush group developed an AL. An elevation in the drain fluid GG was detected using DECT on the day of clinical deterioration. None of the patients in the control group were found to have a positive result on DECT.

CONCLUSION

This study demonstrates the safety of a novel approach to the early detection of AL from extraperitoneal colorectal anastomoses. The technique requires validation in a larger cohort and a multicenter study is planned to investigate the efficacy of GG rectal tube flushes as an early biomarker of AL in low pelvic anastomoses.

AVOID; a phase III, randomised controlled trial using indocyanine green for the prevention of anastomotic leakage in colorectal surgery

INTRODUCTION

Anastomotic leakage (AL) is one of the major complications after colorectal surgery. Compromised tissue perfusion at the anastomosis site increases the risk of AL. Several cohort studies have shown that indocyanine green (ICG) combined with fluorescent near-infrared imaging is a feasible and reproducible technique for real-time intraoperative imaging of tissue perfusion, leading to reduced leakage rates after colorectal resection. Unfortunately, these studies were not randomised. Therefore, we propose a randomised controlled trial to assess the value of ICG-guided surgery in reducing AL after colorectal surgery.

METHODS AND ANALYSIS

A multicentre, randomised controlled clinical trial will be conducted to assess the benefit of ICG-guided surgery in preventing AL. A total of 978 patients scheduled for colorectal surgery will be included. Patients will be randomised between the Fluorescence Guided Bowel Anastomosis group and the Conventional Bowel Anastomosis group. The primary endpoint is clinically relevant AL (defined as requiring active therapeutic intervention or reoperation) within 90 days after surgery. Among the secondary endpoints are 30-day clinically relevant AL, all-cause postoperative complications, all-cause and AL-related mortality, surgical and non-surgical reinterventions, total surgical time, length of hospital stay and all-cause and AL-related readmittance.

ETHICS AND DISSEMINATION

This protocol has been approved by the Medical Ethical Committee Leiden-Den Haag-Delft (METC-LDD) and is registered at ClinicalTrials.gov and trialregister.nl. The results of this study will be reported through peer-reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

NCT04712032; NL7502.

Anastomotic leakage in colorectal cancer surgery

The safety of colorectal surgery for oncological disease is steadily improving, but anastomotic leakage is still the most feared and devastating complication from both a surgical and oncological point of view. Anastomotic leakage affects the outcome of the surgery, increases the times and costs of hospitalization, and worsens the prognosis in terms of short- and long-term outcomes. Anastomotic leakage has a wide range of clinical features ranging from radiological only finding to peritonitis and sepsis with multi-organ failure. C-reactive protein and procalcitonin have been identified as early predictors of anastomotic leakage starting from postoperative day 2-3, but abdominal-pelvic computed tomography scan is still the gold standard for the diagnosis. Several treatments can be adopted for anastomotic leakage. However, there is not a universally accepted flowchart for the management, which should be individualized based on patient's general condition, anastomotic defect size and location, indication for primary resection and presence of the proximal stoma. Non-operative management is usually preferred in patients who underwent proximal faecal diversion at the initial operation. Laparoscopy can be attempted after minimal invasive surgery and can reduce surgical stress in patients allowing a definitive treatment. Reoperation for sepsis control is rarely necessary in those patients who already have a diverting stoma at the time of the leak, especially in extraperitoneal anastomoses. In patients without a stoma who do not require abdominal reoperation for a contained pelvic leak, there are several treatment options, including laparoscopic diverting ileostomy combined with trans-anal anastomotic tube drainage, percutaneous drainage or recently developed endoscopic procedures, such as stent or clip placement or endoluminal vacuum-assisted therapy. We describe the current approaches to treat this complication, as well as the clinical tests necessary to diagnose and provide an effective therapy.

OUP accepted manuscript

Background

Methods

Results

Conclusion

The use of mesenchymal stem cells in animal models for gastrointestinal anastomotic leak: A systematic review

AIM

Anastomotic leak is the most feared complication of gastrointestinal surgery. Mesenchymal stem cell technology is used clinically to promote wound healing; however, the safety and efficacy of this technology on anastomotic healing has yet to be defined. The aim of this study was to investigate whether mesenchymal stem cells confer any benefit when applied to animal models for gastrointestinal anastomotic leak, identify the methodology and how efficacy is assessed.

METHODS

The MEDLINE, EMBASE, WebofScience and Cochrane Library databases were interrogated between 1 January1947 to 1 May 2020. All studies where mesenchymal stem cells were applied to laboratory animal leak models to demonstrate a healing effect were considered. All experimental and histological outcomes were examined. Compliance to ARRIVE and current International Consensus was assessed.

RESULTS

A total of 1205 studies were screened. Twelve studies reported on 438 gastrointestinal anastomoses in four species using 11 models; seven in the colon. No studies utilised a model with a known leak rate. Significant variance was observed in histological outcomes with efficacy demonstrated in five out of 12 studies. One study demonstrated a benefit in leak rate. Colorectal studies had a greater median ARRIVE compliance, 60.8% (IQR 63.2-64.5) compared to noncolorectal 45.4% (IQR 43.8-49.0).

CONCLUSIONS

Mesenchymal stem cell delivery to an animal anastomosis is safe and feasible. Use may confer benefit but findings are currently limited to surrogate histological outcomes. There is consistency in outcome measures reported but variance in how this is assessed. Poor compliance to ARRIVE but good compliance to current international consensus in leak models of the colon was observed.

Multifunctional Magnesium Anastomosis Staples for Wound Closure and Inhibition of Tumor Recurrence and Metastasis

Biodegradable magnesium (Mg) implants spontaneously releasing therapeutic agents against tumors are an intriguing therapeutic approach for both tissue repair and tumor treatment. Anastomotic staples are extensively used for wound closure after surgical resection in patients with colorectal tumors. However, the safety of Mg anastomosis implants for intestinal closure and the effect of tumor suppression remain elusive. Here, we used a high-purity Mg staple to study these issues. Based on the results, we found that it has the potential to heal wounds produced after colorectal tumor resection while inhibiting relapse of residual tumor cells in vitro and in vivo. After implantation of Mg staples for 7 weeks in rabbits, the intestinal wound gradually healed with no adverse effects such as leakage or inflammation. Furthermore, the implanted Mg staples inhibit the growth of colorectal tumor cells and block migration to normal organs because of the increased concentration of Mg ions and released hydrogen. Such an antitumor effect is further confirmed by the in vitro cell experiments. Mg significantly induces apoptosis of tumor cells as well as inhibits cell growth and migration. Our work presents a feasible therapeutic opinion to design Mg anastomotic staples to perform wound healing and simultaneously release tumor suppressor elements in vivo to decrease the risk of tumor recurrence and metastasis.

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.

Perioperative Risk Assessment in Pancreatic Surgery Using Machine Learning

Pancreatic surgery is associated with a high risk for postoperative complications and death of patients. Complications occur in a variable interval after the procedure. Often, a patient has already left the ICU and is not properly monitored anymore when the complication occurs. Risk stratification models can assist in identifying patients at risk in order to keep these patients in ICU for longer. This, in turn, helps to identify complications earlier and increase survival rates. We trained multiple machine learning models on pre-, intra- and short term postoperative data from patients who underwent pancreatic resection at the Department of Surgery, Campus Charité Mitte | Campus Virchow-Klinikum, Charité - Universitätsmedizin Berlin. The presented models achieve an area under the precision-recall curve (AUPRC) of up to 0.51 for predicting patient death and 0.53 for predicting a specific major complication. Overall, we found that a classical logistic regression model performs best for the investigated classification tasks. As more patient data becomes available throughout the perioperative stay, the performance of the risk stratification model improves and should therefore repeatedly be computed.

Early Diagnosis of Anastomotic Leakage After Gastric Cancer Surgery Via Analysis of Inflammatory Factors in Abdominal Drainage

BACKGROUND

Anastomotic leakage (AL) is the most serious postoperative complication for patients with gastric cancer. We aim to develop clinically tools to detect AL in the early phase by analysis of the inflammatory factors (IFs) in abdominal drainage.

METHODS

We prospectively included 326 patients to establish two independent cohorts, and the concentration of IFs within abdominal drainage was detected. In the primary cohort, an IF-based AL prediction model was constructed using the least absolute shrinkage and selection operator (LASSO) regression. The predictive value of the model was later validated via the validation cohort.

RESULTS

Analyzing the IFs with LASSO regression, we developed an Anastomotic Score system on postoperative Day 3 (AScore-POD3), which yielded high diagnostic efficacy in the primary cohort (the area under the curve (AUC) = 0.87). The predictive value of AScore-POD3 was validated in the validation cohort, and its AUC was 0.83. We further built an AScore-POD3 based nomogram by combining the AScore-POD3 system with other clinical risk factors of AL. The C-index of the nomogram was 0.93 in the primary cohort and 0.82 in the validation cohort.

CONCLUSIONS

Our study suggests that AL can be early diagnosed after gastric cancer surgery by measuring drainage IFs.

Real-time fluorescence image-guided gastrointestinal oncologic surgery: Towards a new era

Technological improvements are crucial in the evolution of surgery. Real-time fluorescence-guided surgery (FGS) has spread worldwide, mainly because of its usefulness during the intraoperative decision-making processes. The success of any gastrointestinal oncologic resection is based on the anatomical identification of the primary tumor and its regional lymph nodes. FGS allows also to evaluate the blood perfusion at the gastrointestinal stumps after colorectal or esophageal resections. Therefore, a reduction on the anastomotic leak rates has been postulated as one of the foreseeable benefits provided by the use of FGS in these procedures. Although the use of fluorescence in lymph node detection was initially described in breast cancer surgery, the technique is currently applied in gastric or splenic flexure cancers, as they both present complex and variable lymphatic drainages. FGS allows also to perform intraoperative lymphograms or sentinel lymph node biopsies. New applications of FGS are being developed to assist in the detection of peritoneal metastases or in the evaluation of the tumor resection margins. The present review aims to provide a general overview of the current status of real-time FGS in gastrointestinal oncologic surgery. We put a special focus on the different applications of FGS, discussing the main findings and limitations found in the contemporary literature and also the promising near future applications.

The importance of rectal contrast in CT assessment to detect anastomotic leakage after colorectal surgery

AIM

Computed tomography (CT) is currently the diagnostic tool most often used to detect anastomotic leakage (AL) after colorectal surgery. The aim of this study was to investigate the value of rectal contrast.

METHOD

All patients who underwent colorectal surgery with a primary anastomosis between 2009 and 2018 were identified from a prospectively maintained database. Patients who underwent postoperative CT scanning in suspicion of AL were included. The clinical and radiological outcomes of patients with and without rectal contrast were compared.

RESULTS

A total of 1183 patient records were reviewed; 225 patients underwent CT-abdomen in suspicion of AL. Of these patients, 175 (77.8%) received rectal contrast. Sensitivity and specificity in this group were 78% and 94%, respectively. The positive predictive value (PPV) was 0.78 and the negative predictive value (NPV) was 0.94. In the group without rectal contrast (n = 50), sensitivity was 47%, specificity 88%, PPV 0.66 and NPV 0.76. In patients who received rectal contrast, contrast reached the anastomosis in 81.7% compared with 26.0% in patients who were given only oral contrast (p < 0.001). The sensitivity increased to 93% in the group of patients with contrast at the anastomosis, the specificity to 97%, the PPV to 0.88 and the NPV to 0.98. No adverse events were observed after the use of rectal contrast.

CONCLUSION

The use of rectal contrast led to a significant increase in the predictive value of CT scanning for AL, especially when it reached the anastomosis. This suggests that rectal contrast is a safe and useful adjunct to CT-abdomen in the detection of AL.

Role of near-infrared fluorescence in colorectal surgery

Near-infrared fluorescence (NIRF) is a technique of augmented reality that, when applied in the operating theatre, allows the colorectal surgeon to visualize and assess bowel vascularization, to identify lymph nodes draining a cancer site and to identify ureters. Herein, we review the literature regarding NIRF in colorectal surgery.

"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.

Intraoperative surgeon probe inspection compared to leak testing for detecting gaps in canine jejunal continuous anastomoses: A cadaveric study

OBJECTIVE

To compare the detection of gaps in jejunal continuous anastomoses by probing (PT) versus leak testing (LT).

STUDY DESIGN

Experimental study.

ANIMALS

Normal jejunal segments (n = 24) from two fresh canine cadavers.

METHODS

Intestinal segments were randomly selected by four volunteers who created six simple continuous anastomoses: two constructs using standard technique with 2-3 mm suture spacing (ST, 8 total), and four constructs with one 4-mm gap (IG, 16 total). All 24 anastomoses were examined with PT (1 volunteer) prior to LT (3 volunteers). LT was performed within a maximal peristaltic pressure range (34-54 cmH₂ O). The presence and location of anastomotic leaks (L_A ) detected with LT were compared with gaps detected with PT.

RESULTS

Nineteen out of twenty-four (79.2%) samples had at least one probe drop, and four out of twenty-three (17.4%) samples leaked. LT results from one sample were excluded due to iatrogenic suture failure. PT was 100% sensitive (95% CI: 51.01, 100%) with a 100% negative predictive value (95% CI: 56.55, 100%) at detecting gaps compared with LT. The location of all L_A was accurately identified with PT and confirmed during LT.

CONCLUSION

PT was highly sensitive at detecting gaps compared with LT. All L_A were accurately detected by PT. None of the segments negative during PT leaked.

CLINICAL SIGNIFICANCE

The diagnostic value of PT appears adequate to recognize gaps in cadaveric small intestinal anastomoses. PT offers surgeons an alternative to detect suture gaps that may contribute to postoperative dehiscence of intestinal anastomoses.

Post-Operative Monitoring of Intestinal Tissue Oxygenation Using an Implantable Microfabricated Oxygen Sensor

Anastomotic leakage (AL) is a common and dangerous post-operative complication following intestinal resection, causing substantial morbidity and mortality. Ischaemia in the tissue surrounding the anastomosis is a major risk-factor for AL development. Continuous tissue oxygenation monitoring during the post-operative recovery period would provide early and accurate early identification of AL risk. We describe the construction and testing of a miniature implantable electrochemical oxygen sensor that addresses this need. It consisted of an array of platinum microelectrodes, microfabricated on a silicon substrate, with a poly(2-hydroxyethyl methacrylate) hydrogel membrane to protect the sensor surface. The sensor was encapsulated in a biocompatible package with a wired connection to external instrumentation. It gave a sensitive and highly linear response to variations in oxygen partial pressure in vitro, although over time its sensitivity was partially decreased by protein biofouling. Using a pre-clinical in vivo pig model, acute intestinal ischaemia was robustly and accurately detected by the sensor. Graded changes in tissue oxygenation were also measurable, with relative differences detected more accurately than absolute differences. Finally, we demonstrated its suitability for continuous monitoring of tissue oxygenation at a colorectal anastomosis over a period of at least 45 h. This study provides evidence to support the development and use of implantable electrochemical oxygen sensors for post-operative monitoring of anastomosis oxygenation.

MRI-enema for the assessment of pelvic intestinal anastomotic integrity

AIM

Anastomotic leak causes significant morbidity for patients undergoing pelvic intestinal surgery. Fluoroscopic assessment of anastomotic integrity using water-soluble contrast enema (WSCE) is of questionable benefit over examination alone. We hypothesized that MRI-enema may be more accurate. The aim of this study was to compare MRI-enema with fluoroscopic WSCE.

METHOD

Patients referred for WSCE with pelvic intestinal anastomosis and defunctioning ileostomy (including patients with suspected or known leaks) were invited to participate. WSCE and MRI-enema were undertaken within 48 h of each other. MRI sequences were performed before, during and immediately after the introduction of 400 ml of 1% gadolinium contrast solution per anus. MRI examinations were reported to protocol by two blinded gastrointestinal radiologists. A Likert-scale patient questionnaire was administered to compare patient experience. Follow-up was >12 months after ileostomy reversal. Anastomotic leak was determined by unblinded consensus of examination and radiological findings.

RESULTS

Sixteen patients were recruited, with a median age of 39 years (range 22-69). Ten were men, 11 had ileoanal pouch formation and five had low anterior resection. Five patients had anastomotic leak identified by MRI and four by WSCE. The radial location of the anastomotic defect was identified in all five patients by MRI versus two on WSCE. MRI revealed additional information including contents of a widened presacral space. Patient experience was equivalent. Eleven patients eventually had ileostomy reversal without complications.

CONCLUSION

MRI-enema is a feasible and tolerable alternative to WSCE and offers greater anatomical detail in the context of pelvic intestinal anastomotic leak. Larger prospective studies are required to define its potential role in the UK National Health Service.

The role of CRP in the diagnosis of postoperative complications in rectal surgery

Postoperative complications of rectal resections classified as grade III or higher according to Clavien-Dindo system, which also include anastomotic leaks, are usually life-threatening conditions. Delayed diagnosis may account for almost 18% of deaths. Due to nonspecific clinical signs in the early postoperative period, diagnosing these complications may truly be a challenge for clinicians. Nowadays, with the implementation of the ERAS protocol (enhanced recovery after surgery) and efforts concentrated on quickly delivered treatment to patients suffering from the above-mentioned complications, an appropriate marker with high specificity is required. Postoperative levels of C-reactive protein in blood serum seem promising in this aspect. The presented study aimed to determine the cut-off level of serum C-reactive protein as a possible predictive factor for early diagnosis of serious postoperative complications associated with rectal resections. This could also lead clinicians to the diagnosis of anastomotic leak after other possible options are ruled out. This study is a retrospective observational analysis of patients who underwent open resection of rectal cancer during a one-year period. Collected data included risk factors (age, gender, BMI, bowel preparation), record of complications and C Reactive Protein (CRP) serum levels. The study included 162 patients. Uncomplicated postoperative course was observed in 58 patients (35.8%). Complications were present in 104 cases (64.2%), including surgical site infections (16.7%) and anastomotic leak (9.9%). The mortality rate was 2.5%. Serum CRP threshold predicting relevant complications reached a sensitivity of 83.3% and specificity of 82.7% on POD 4, with a 175.4 mg/L cut-off value, burdened with a 95.7% negative predictive value. Postoperative serum C-reactive protein may be used as a good predictor of infectious complications, including anastomotic leaks. Measuring CRP levels in the early postoperative period may facilitate identification oflow-risk patients ensure early and safe discharges from hospital after rectal resections.

Early prediction of anastomotic leakage after laparoscopic rectal surgery using creactive protein

At present, anterior resection of the rectum or transabdominal rectal resection is the most common surgical technique for rectal cancer. Laparoscopic techniques are popular, and the efficacy and safety of laparoscopic rectal surgery have been confirmed. However, postoperative anastomotic leakage is a common, severe complication that leads to high mortality. Thus, early diagnosis of anastomotic leakage is important for reducing clinical consequences.The aim of this study was to determine whether C-reactive protein (CRP) is a good predictor of anastomotic leakage in laparoscopic transabdominal rectal resection.Our retrospective study involved a series of 196 rectal cancer patients who underwent laparoscopic transabdominal rectal resection without ileostomy between May 2013 and April 2015 at the Sir Run Run Shaw Hospital, Zhejiang University College of Medicine. The following patient data were collected: demographic data, manifestations of the complication, CRP levels and neutrophil percentage during the first 7 postoperative days.Anastomotic leakage was detected in 11 patients (5.6%). Each group showed significant differences (P < .05) in CRP levels on postoperative days 3 to 7; compared with other groups, the anastomotic leakage group showed significant differences in CRP levels (P < .05) on postoperative day 6. When patients were divided into groups with or without anastomotic leakage, CRP was a reliable predictor on postoperative days 4 to 7 (P < .05, area under the curve > 0.800). The best combination was CRP on postoperative day 6 (area under the curve = 0.932) with a cut-off of 76.6 mg/L, resulting in a sensitivity of 83.3%, a specificity of 94.6% and a negative predictive value of 99%.CRP is a reliable predictor of anastomotic leakage after laparoscopic transabdominal rectal resection surgery. High CRP levels on postoperative days 4 to 7 indicate the need for a more careful patient evaluation.

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.

Evaluation of Fibrin Sealant in Prevention of Cervical Anastomotic Leakage After McKeown Esophagectomy: A Single-Center, Retrospective Study

BACKGROUND

Anastomotic leakage remains an issue after esophagectomy for patients with esophageal or esophagogastric junction cancer. Previous studies have indicated that the intraoperative application of fibrin sealant may reduce the incidence of postoperative anastomotic leakage. This retrospective study was aimed to evaluate the efficacy and safety of fibrin sealant in the prevention of anastomotic leakage in patients undergoing McKeown esophagectomy.

METHODS

We designed a single-center, retrospective study. Between January 2018 and December 2019, 227 patients with esophageal or esophagogastric junction cancer undergoing McKeown esophagectomy performed by our team were retrospectively identified, of whom 86 patients were included in the FS group and 141 patients were included in the control group. Intraoperatively, 2.5 ml of porcine fibrin sealant was applied circumferentially to the cervical anastomosis after the anastomosis was created in the FS group. The primary outcome was the incidence of cervical anastomotic leakage within the first three months after surgery.

RESULTS

The differences in baseline clinical characteristics between the two groups were not significant except for a history of drinking. In the FS group, the postoperative cervical anastomotic leakage rate was lower (FS group: 4.7% [4 of 82] vs. control group: 19.9% [28 of 141], p < 0.01). Multivariate logistic regression showed that the intraoperative application of fibrin sealant was an independent protective factor for anastomotic leakage (OR 0.169, 95% CI 0.055-0.515, p = 0.002).

CONCLUSIONS

The intraoperative application of fibrin sealant could possibly prevent cervical anastomotic leakage after McKeown esophagectomy with satisfactory safety. Further prospective clinical trials are warranted.

How to reduce failure to rescue after visceral surgery?

Mortality after visceral surgery has decreased owing to progress in surgical techniques, anesthesiology and intensive care. Mortality occurs in 5-10% of patients after major surgery and remains a topic of interest. However, the ratio of mortality after postoperative complications in relation to overall complications varies between hospitals because of failure to rescue at the time of the complication. There are multiple factors that lead to complication-related mortality: they are patient-related, disease-related, but are related, above all, to the timeliness of diagnosis of the complication, the organisational aspects of management in private or public hospitals, hospital volume that corresponds to the centralisation of initial management or to the concept of referral centre in case of complications, to the team spirit, to communication between the health care providers and to the management of the complication itself. Several organisational advances are to be considered, such as the development of shorter hospitalisations and notably ambulatory surgery, as well as enhanced recovery programs. Remote monitoring and the contribution of artificial intelligence must also be evaluated in this context. The reduction of mortality after visceral surgery rests on several tactics: prevention of potentially lethal complications, the all-important reduction of failure to rescue, and risk management before, during and after hospitalisations that are increasingly shorter.

The Association of Coloproctology of Great Britain and Ireland consensus guidelines in emergency colorectal surgery

AIM

There is a requirement for an expansive and up to date review of the management of emergency colorectal conditions seen in adults. The primary objective is to provide detailed evidence-based guidelines for the target audience of general and colorectal surgeons who are responsible for an adult population and who practise in Great Britain and Ireland.

METHODS

Surgeons who are elected members of the Association of Coloproctology of Great Britain and Ireland Emergency Surgery Subcommittee were invited to contribute various sections to the guidelines. They were directed to produce a pathology-based document using literature searches that were systematic, comprehensible, transparent and reproducible. Levels of evidence were graded. Each author was asked to provide a set of recommendations which were evidence-based and unambiguous. These recommendations were submitted to the whole guideline group and scored. They were then refined and submitted to a second vote. Only those that achieved >80% consensus at level 5 (strongly agree) or level 4 (agree) after two votes were included in the guidelines.

RESULTS

All aspects of care (excluding abdominal trauma) for emergency colorectal conditions have been included along with 122 recommendations for management.

CONCLUSION

These guidelines provide an up to date and evidence-based summary of the current surgical knowledge in the management of emergency colorectal conditions and should serve as practical text for clinicians managing colorectal conditions in the emergency setting.

Intraperitoneal microdialysis detects intestinal leakage earlier than hemodynamic surveillance and systemic inflammation in a pig model

OBJECTIVE

Anastomotic leakage is a common complication following large abdominal surgery, often developing to life-threatening abdominal sepsis due to late diagnosis. Currently, diagnostics rely on systemic hemodynamic and infection monitoring. We hypothesized that intraperitoneal microdialysis allows detection of peritonitis prior to changes in standard clinical parameters in a pig model.

MATERIALS AND METHODS

We included six pigs; five underwent intraperitoneal fecal contamination, one had sham surgery for a total of 10 h. Microdialysis was established in four intraabdominal quadrants and two hepatic lobes. All pigs were hemodynamically monitored with pulmonary artery and femoral artery catheters. Blood samples were assessed for inflammatory markers, terminal complement complex (TCC), interleukin (IL)-6, IL-10, and plasminogen activator inhibitor-1 (PAI-1).

RESULTS

Microdialysis showed intraperitoneal lactate increase during the first two hours after fecal contamination, which remained elevated throughout the observation time with concurrent decrease of glucose. Arterial lactate remained within reference range (<1,6mM). Systemic inflammatory markers TCC, IL-6, IL-10 and PAI-1 increased significantly after minimum four hours. Mean arterial pressure, stroke volume variation and cardiac output were not compromised the first five hours. Sham surgery did not influence any of the parameters.

CONCLUSION

Intraperitoneal fecal contamination leads to a rapid and pronounced intraperitoneal increase in lactate, decrease in glucose while pyruvate and glycerol levels remain unchanged. This distinct metabolic pattern of peritoneal inflammation can be easily detected by microdialysis. Observation of this pattern may minimize time to safe diagnosis of intestinal perforations after intraperitoneal fecal contamination.

Colorectal resection in endometriosis patients: correlation between histopathological findings and postoperative outcome

Introduction

Endometriosis is associated with a high number of chronic pelvic pain and reduced quality of life. Colorectal resections in case of bowel involvement of endometriosis are associated with an unneglectable morbidity in young and healthy patients. There is no linear correlation established between the degree of symptoms and stage of endometriosis. The aim of this study was to correlate the histological findings to preoperative pain scores in colorectal resected patients with endometriosis.

Methods

Twenty-five patients who underwent laparoscopic colorectal resection for endometriosis between 2014 and 2019 were included in this retrospective study. Pain level was assessed preoperatively and postoperatively via phone call in May 2020. Histopathology was correlated to preoperative symptoms and postoperative outcome.

Results

Average follow-up time was 38.68 months (± 19.92). Preoperative VAS-score was 8.32 (± 1.70). We observed a significant reduction of pain level in all patients after surgery (p ≤ 0.005). Pain levels were equal regarding the presence of satellite spots and various degrees of infiltration depth. The resection margins were clear in all patients. Postoperative complications occurred in 6 cases (24%) and anastomotic leakage was observed in 3 patients (12%). Average VAS-score at time of follow-up was 1.70 (± 2.54).

Conclusion

Our data demonstrate that adequate colorectal resection leads to reduction of pain and an increase of quality of life irrespective of histopathological findings. An experienced team is necessary to improve intraoperative outcome and to reduce postoperative morbidity in case of complication.

Outcomes of Intra- versus Extra-Corporeal Ileocolic Anastomosis after Minimally Invasive Right Colectomy for Cancer: An Observational Study

Intracorporeal anastomoses (IA) are increasingly being used in colorectal surgery. Some data suggest that these might confer benefits compared with extracorporeal anastomoses (EA). The aim of this study is to compare the short-term complications associated with IA versus EA for minimally invasive right colectomy. This is a single-centre, retrospective study on a prospective database. Patients who underwent minimally invasive right colectomy for cancer between January 2017 and December 2019 were assessed for inclusion. The primary outcome was global 30-day morbidity. Overall, 189 patients were included, of whom 102 had IA. Global morbidity and medical complications were higher in patients with EA (23.5% vs. 40.2%, p = 0.014; 5.9% vs. 14.9%, p = 0.039, respectively). None of the patients with IA had non-infectious surgical wound complications, compared to 4.6% in the EA group (p = 0.029). No differences were found in anastomotic leakage (9.8% vs. 10.3%, p = 0.55). At multivariable analysis, EA was an independent risk factor for both surgical (OR = 3.71 95% CI: 1.06-12.91, p = 0.04) and overall complications (OR = 3.58 95% CI: 1.06-12.12, p = 0.04). IA lowers the risk for global, medical, and surgical complications with minimum risk for wound complications, without increasing the risk of AL.

Lactate Level as a Prediction Factor of Reperforation after Repairing Gastric Perforation

Reperforation after gastric perforation repair is a complication which increases the rate of morbidity and mortality in gastric perforation. The lack of ability of the tissue to use oxygen in septic condition causes anaerobic cellular metabolism and furthermore it will cause failure in closing the perforation. The production of anaerobic metabolism is lactic acid which can be measured from the blood. The aim of this study is to determine the cut-off point of blood lactate level as a predictor of reperforation after repairing gastric perforation. Forty-six patients diagnosed as gastric perforation, who were repaired in Dr Soetomo Hospital from October 2014 to October 2015 were recruited as samples. Serum lactate was taken one hour before repairing the perforation. After being repaired, the patients were observed until the 14th day to evaluate whether any reperforation would occur or not . The design of this research was cross-sectional, analytic observational. The data was analyzed using independent t-test and ROC for obtaining the cut-off point as a predictor of the reperforation after the gastric perforation was repaired. There was a significant difference in the mean of lactate level in the group with reperforation compared with that of the non-reperforation group, that is as big as 3.74±0.59 mmol/L and 2.60±0.76 mmol/L. Using ROC curve analysis, there was the cut-off point of lactate level for reperforation 3.35 mmol/L, with sensitivity 92.9%, specificity 84.4%, positive predictive value 72% and negative predictive Value 96.4%, accuracy 87.0% and in the AUC value 0.902.

Indocyanine green fluorescence angiography prevents anastomotic leakage in rectal cancer surgery: a systematic review and meta-analysis

BACKGROUND

The role of intraoperative use of indocyanine green (ICG) fluorescence angiography (ICGFA) to prevent anastomotic leakage (AL) in rectal cancer surgery remains controversial.

METHODS

The systematic review for studies evaluating ICGFA in patients undergoing rectal cancer surgery in PubMed, Embase, Web of Science, and the Cochrane Library was performed up to April 30, 2020. The primary outcome was the incidence of AL. The analysis was performed using RevMan v5.3 and Stata v12.0 software.

RESULTS

Eighteen studies comprising 4038 patients were included. In the present meta-analysis, intraoperative use of ICGFA markedly reduced AL rate (OR = 0.33; 95% CI: 0.24-0.45; P < 0.0001; I² = 0%) in rectal cancer surgery, which was still significant in surgeries limited to symptomatic AL (OR = 0.44; 95% CI: 0.31-0.64; P < 0.0001; I² = 22%). This intervention was also associated with shorter postoperative stays (MD = - 1.27; 95% CI: - 2.42 to - 0.13; P = 0.04; I² = 60%). However, reoperation rate (OR = 0.61; 95% CI: 0.34-1.10; P = 0.10; I² = 6%), ileus rate (OR = 1.30; 95% CI: 0.60-2.82; P = 0.51; I² = 56%), and surgical site infection rate (OR = 1.40; 95% CI: 0.62-3.20; P = 0.42; I² = 0%) were not significantly different between the two groups.

CONCLUSION

The use of ICGFA was associated with a lower AL rate after rectal cancer resection. However, more multi-center RCTs with large sample size are required to further verify the value of ICGFA in rectal cancer surgery.

Matrix metalloproteinase-9 in relation to patients with complications after colorectal surgery: a systematic review

PURPOSE

Anastomotic leakage (AL) is the most severe complication following colorectal resection and is associated with increased mortality. The main group of enzymes responsible for collagen and protein degradation in the extracellular matrix is matrix metalloproteinases. The literature is conflicting regarding anastomotic leakage and the degradation of extracellular collagen by matrix metalloproteinase-9 (MMP-9). In this systematic review, the possible correlation between anastomotic leakage after colorectal surgery and MMP-9 activity is investigated.

METHODS

Embase, MEDLINE, Cochrane, and Web of Science databases were searched up to 3 February 2020. All published articles that reported on the relationship between MMP-9 and anastomotic leakage were selected. Both human and animal studies were found eligible. The correlation between MMP-9 expression and anastomotic leakage after colorectal surgery.

RESULTS

Seven human studies and five animal studies were included for analysis. The human studies were subdivided into those assessing MMP-9 in peritoneal drain fluid, intestinal biopsies, and blood samples. Five out of seven human studies reported elevated levels of MMP-9 in patients with anastomotic leakage on different postoperative moments. The animal studies demonstrated that MMP-9 activity was highest in the direct vicinity of an anastomosis. Moreover, MMP-9 activity was significantly reduced in areas further proximally and distally from the anastomosis and was nearly or completely absent in uninjured tissue.

CONCLUSION

Current literature shows some relation between MMP-9 activity and colorectal AL, but the evidence is inconsistent. Innovative techniques should further investigate the value of MMP-9 as a clinical biomarker for early detection, prevention, or treatment of AL.

Review of Colonic Anastomotic Leakage and Prevention Methods

Although surgeries involving anastomosis are relatively common, anastomotic leakages are potentially deadly complications of colorectal surgeries due to increased risk of morbidity and mortality. As a result of the potentially fatal effects of anastomotic leakages, a myriad of techniques and treatments have been developed to treat these unfortunate cases. In order to better understand the steps taken to treat this complication, we have created a composite review involving some of the current and best treatments for colonic anastomotic leakage that are available. The aim of this article is to present a background review of colonic anastomotic leakage, as well as current strategies to prevent and treat this condition, for a broader audience, including scientist, engineers, and especially biomedical engineers.

Procalcitonin as an Early Predictor of Intra-abdominal Infections Following Gastric Cancer Resection

BACKGROUND

The purpose of this study was to investigate the prognostic value of postoperative procalcitonin (PCT) and C-reactive protein (CRP) for their ability to detect Intra-abdominal infections (IAIs) in patients after GC surgery.

METHODS

Patients who underwent elective gastrectomy for primary GC were retrospectively enrolled between October 2018 and October 2019. The PCT and CRP levels and white blood cell (WBC) count were measured before surgery and on postoperative days (POD) 1, 3, 5, and 7. The differences in serum PCT, CRP, and WBC levels between IAIs and non-IAIs groups were compared. Diagnostic accuracy was determined by the area under the receiver operating characteristic curve. Univariate and multivariate logistic regression analyses identified independent clinical factors that predicted postoperative IAIs.

RESULTS

A total of 155 patients who underwent GC surgery were enrolled. IAIs were observed in 12 patients (7.74%). The postoperative CRP and PCT values in the IAI group were higher than those in the non-IAI group. PCT had superior diagnostic accuracy on POD 3 (area under the curve 0.769) with an optimal cutoff value of 2.03 ng/mL, yielding 75% sensitivity, 87.4% specificity, and 97.6% negative predictive value. Multivariate analysis identified a PCT level of 2.03 mg/mL or greater on POD 3 as a significant predictive factor for IAIs after gastrectomy (odds ratio: 21.447, 95% confidence interval: 5.081-91.672).

CONCLUSIONS

PCT values less than 2.03 ng/mL on POD 3 is an excellent negative predictor of IAIs, which may ensure a safe early discharge after gastric cancer surgery.

Computed tomography in suspected anastomotic leakage after colorectal surgery: evaluating mortality rates after false-negative imaging

PURPOSES

We sought to investigate the accuracy of abdominal CT scanning for anastomotic leakage and the effect of false-negative scans on the delay in therapeutic intervention and clinical outcome.

METHOD

Data from a prospectively bi-institutionally maintained database of all patients who underwent elective colorectal surgery with primary anastomosis for malignant or benign disease between 2010 and 2017 were reviewed. Patients with confirmed anastomotic dehiscence at reintervention who underwent a postoperative CT scan for suspected leakage were identified and radiological reports were retrieved.

RESULTS

Seventy-six patients with anastomotic dehiscence were included in the study. American Society of Anesthesiologists score, sex, type of surgical procedure, malignancy, and type of anastomosis do not correlate with postoperative false-negative CT imaging. Postoperative false-negative CT scan, however, led to delayed reintervention (3 vs. 6 h, p = 0.023) and increased mortality (five deaths vs. no deaths, p = 0.043). Free abdominal air (p = 0.001) and extraluminal contrast extravasation (p = 0.001) were found to be predictive of accuracy in anastomotic leakage diagnosis.

CONCLUSION

The suboptimal specificity of a postoperative CT scan in suspected anastomotic leakage after colorectal surgery can delay reintervention and increase mortality.

Anastomotic leak after surgery for colon cancer and effect on long-term survival

AIM

An anastomotic leak after surgery for colon cancer is a recognized complication but how it may adversely affect long-term survival is less clear because data are scarce. The aim of the study was to investigate the long-term impact of Grade C anastomotic leak in a large, population-based cohort.

METHOD

Data on patients undergoing resection for Stage I-III colon cancer between 2008 and 2012 were collected from the Swedish, Norwegian and Danish Colorectal Cancer Registries. Overall relative survival and conditional 5-year relative survival, under the condition of surviving 1 year, were calculated for all patients and stratified by stage of disease.

RESULTS

A total of 22 985 patients were analysed. Anastomotic leak occurred in 849 patients (3.7%). Five-year relative survival in patients with anastomotic leak was 64.7% compared with 87.0% for patients with no leak (P < 0.001). Five-year relative survival among the patients who survived the first year was 88.6% vs 81.3% (P = 0.003). Stratification by cancer stage showed that anastomotic leak was significantly associated with decreased relative survival in patients with Stage III disease (P = 0.001), but not in patients with Stage I or II (P = 0.950 and 0.247, respectively).

CONCLUSION

Anastomotic leak after surgery for Stage III colon cancer was associated with significantly decreased long-term relative survival.