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

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.

Abnormal vital signs after laparoscopic colorectal surgery: More common than you think

BACKGROUND

Anastomotic leak is a feared complication. The presence of abnormal vital signs is often cited as an important overlooked predictive clue in retrospective settings once the diagnosis of leak has already been established. We aimed to determine the prevalence of abnormal vital signs following colorectal resection and assess its predictive value.

METHODS

We retrospectively studied patients undergoing colorectal resection. The performance of vital signs in predicting anastomotic leak was assessed using discrete-time survival analysis and receiver operator characteristic curve.

RESULTS

1662 patients (841 laparoscopic, 821 open) were included. Clinical anastomotic leak was diagnosed in 50 patients (3.1%). 96.8% of patients of the entire cohort had at least one abnormal vital sign during their postoperative course. No individual vital sign was a strong predictor of anastomotic leak in either laparoscopic or open cohorts.

CONCLUSION

Vital sign abnormalities are extremely common following open and laparoscopic colorectal surgery and alone are poor predictors of anastomotic leak.

Predictors of complications from stoma closure in elective colorectal surgery: an assessment from the American College of Surgeons National Surgical Quality Improvement Program (ACSNSQIP)

BACKGROUND

There is significant morbidity after diverting ileostomy closure, so identifying predictors of complications could be of great benefit. The aim of our study was to evaluate the incidence and risk factors for postoperative morbidity after elective ileostomy closure.

METHODS

The ACS-NSQIP dataset was evaluated for elective ileostomy closures from 1/1/2015 to 12/31/2016. Demographic characteristics, operative, and postoperative outcomes were evaluated. The primary outcome was 30-day major morbidity (Clavien class III and greater). Secondary outcomes were rates and predictors of major morbidity, superficial site infection (SSI), reoperation, and readmission from multivariate logistic regression modeling.

RESULTS

We retrospectively evaluated 1885 patients. The median operative time was 65 (IQR 50-90) minutes and median length of stay was 3 (IQR 2-5) days. Major morbidity was recorded in 6.7%, including mortality (1.0%), deep/organ space SSI (2.6%), dehiscence (0.8%), reintubation (0.5%), sepsis (1.7%), septic shock (0.8%), and reoperation (3.7%). Readmission was recorded in 9.7% and 6.2% had SSI. Multivariate logistic regression showed male sex (OR 1.584; 95% CI 1.068-2.347; p = 0.022) and longer operative time (OR 1.004; 95% CI 1.001-1.007; p = 0.009) were among those variables associated with increased odds of major morbidity. Dyspnea (OR 2.431; 95% CI 1.139-5.094; p = 0.021) and longer operative time (OR 1.003; 95% CI 1.001-1.007; p = 0.034) were among the independent risk factors for SSI. Male sex (OR 2.246; 95% CI 1.297-3.892; p = 0.004, chronic obstructive pulmonary disease (OR 2.959; 95% CI 1.153-7.591; p = 0.024), and longer operative time (OR 1.005; 95% CI 1.001-1.009; p = 0.011) were associated with increased odds of reoperation. Chronic obstructive pulmonary disease (OR 2.578; 95% CI 1.338-4.968; p = 0.005), wound infection (OR 2.680; 95% CI 1.043-6.890; p = 0.041), and inflammatory bowel disease (OR 2.565; 95% CI 1.203-5.463; p = 0.015) were associated with increased odds of readmission.

CONCLUSIONS

Elective stoma closure has significant risk of morbidity. Patients with longer operative times were at increased risk for major morbidity, overall SSI, and reoperation. From the analysis, factors specifically associated with major morbidity, overall infectious complications, readmissions, and reoperations were identified. This information can be used to prospectively prepare for these high-risk patients, potentially improving postoperative outcomes.

The Bucharest ESTES consensus statement on peritonitis

INTRODUCTION

Peritonitis is still an important health problem associated with high morbidity and mortality. A multidisciplinary approach to the management of patients with peritonitis may be an important factor to reduce the risks for patients and improve efficiency, outcome, and the cost of care.

METHODS

Expert panel discussion on Peritonitis was held in Bucharest on May 2017, during the 17th ECTES Congress, involving surgeons, infectious disease specialists, radiologists and intensivists with the goal of defining recommendations for the optimal management of peritonitis.

CONCLUSION

This document is an updated presentation of management of peritonitis and represents the summary of the final recommendations approved by a panel of experts.

Is abdominal vascular calcification score valuable in predicting the occurrence of colorectal anastomotic leakage? A meta-analysis

OBJECTIVE

Anastomotic leakage (AL) is a catastrophic surgical complication affecting the prognosis of patients after colorectal surgery. We aimed to determine the value of the arterial calcification (AC) score in predicting AL.

METHODS

Medline and Embase were searched through November 2019. The odds ratio (OR) and 95% confidence interval (CI) were used to estimate the association between AC and AL after colorectal surgery. The fixed-effects model or random-effects model was adopted for data pooling. Subgroup analyses were conducted to assess the effect of different aortoiliac trajectories.

RESULTS

Four studies involving 496 patients were included. The calcium volume and calcium score measurements of different trajectories revealed a significant difference with regard to the left and right common iliac arteries, the superior mesenteric artery, and the left common iliac artery. Calcification of the internal iliac artery significantly increased the risk of AL compared with no AL (OR = 1.005; 95% CI 1.002-1.009; P = 0.005), as did calcification of the left internal iliac artery (OR = 1.009; 95% CI 1.002-1.016; P = 0.011), but not of the common iliac artery (OR = 1.001; 95% CI 1.000-1.001; P = 0.317) or common and internal iliac artery (OR = 1.000; 95% CI 1.000-1.000; P = 1.000).

CONCLUSIONS

AC is associated with increased risk of AL following colorectal surgery.

TRIAL REGISTRATION

CRD42019141236.

Experimental fortification of intestinal anastomoses with nanofibrous materials in a large animal model

Anastomotic leakage is a severe complication in gastrointestinal surgery. It is often a reason for reoperation together with intestinal passage blockage due to formation of peritoneal adhesions. Different materials as local prevention of these complications have been studied, none of which are nowadays routinely used in clinical practice. Nanofabrics created proved to promote healing with their structure similar to extracellular matrix. We decided to study their impact on anastomotic healing and formation of peritoneal adhesions. We performed an experiment on 24 piglets. We constructed 3 hand sutured end-to-end anastomoses on the small intestine of each pig. We covered the anastomoses with a sheet of polycaprolactone nanomaterial in the first experimental group, with a sheet of copolymer of polylactic acid with polycaprolactone in the second one and no fortifying material was used in the Control group. The animals were sacrificed after 3 weeks of observation. Clinical, biochemical and macroscopic signs of anastomotic leakage or intestinal obstruction were monitored, the quality of the scar tissue was assessed histologically, and a newly developed scoring system was employed to evaluate the presence of adhesions. The material is easy to manipulate with. There was no mortality or major morbidity in our groups. No statistical difference was found inbetween the groups in the matter of level of peritoneal adhesions or the quality of the anastomoses. We created a new adhesion scoring system. The material appears to be safe however needs to be studied further to prove its' positive effects.

Transanal drainage tube: alternative option to defunctioning stoma in rectal cancer surgery?

BACKGROUND

Anastomotic leakage (AL) remains the most dreaded complication after rectal cancer surgery. The aim of this study was to evaluate the role of transanal drainage tube in reducing the incidence, severity and hospital costs respect to defunctioning stoma (DS).

METHODS

Considering 429 patients consecutively operated for rectal adenocarcinoma, the tube was placed in 275 (Group A) and not placed in 154 (Group B) patients. A DS was created in a subgroup of 54 patients among the latter.

RESULTS

The incidence of AL was significantly higher in Group B (P=0.007). In patients with DS, the incidence was higher than Group A (P=NS). Grade C complications were significantly higher in Group B (P=0.006) and Grade B complications were significantly higher in patients with DS (P=0.03). Estimated economic benefit was 4,000 Euros for each patient.

CONCLUSIONS

Transanal drainage tube may be a safe and effective alternative to DS in many cases. The incidence of leakage and Grade C complications are reduced albeit not significantly but Grade B complications are significantly lower. Although the AL incidence was similar in our experience, the tube allows to avoid a stoma-related consequence and the need for reversal procedure with economic benefit.

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

BACKGROUND

Both obesity and the presence of collagenolytic bacterial strains (Enterococcus faecalis) can increase the risk of anastomotic leak. The aim of this study was to determine whether mice chronically fed a high-fat Western-type diet (WD) develop anastomotic leak in association with altered microbiota, and whether this can be mitigated by a short course of standard chow diet (SD; low fat/high fibre) before surgery.

METHODS

Male C57BL/6 mice were assigned to either SD or an obesogenic WD for 6 weeks followed by preoperative antibiotics and colonic anastomosis. Microbiota were analysed longitudinally after operation and correlated with healing using an established anastomotic healing score. In reiterative experiments, mice fed a WD for 6 weeks were exposed to a SD for 2, 4 and 6 days before colonic surgery, and anastomotic healing and colonic microbiota analysed.

RESULTS

Compared with SD-fed mice, WD-fed mice demonstrated an increased risk of anastomotic leak, with a bloom in the abundance of Enterococcus in lumen and expelled stool (65-90 per cent for WD versus 4-15 per cent for SD; P = 0·010 for lumen, P = 0·013 for stool). Microbiota of SD-fed mice, but not those fed WD, were restored to their preoperative composition after surgery. Anastomotic healing was significantly improved when WD-fed mice were exposed to a SD diet for 2 days before antibiotics and surgery (P < 0·001).

CONCLUSION

The adverse effects of chronic feeding of a WD on the microbiota and anastomotic healing can be prevented by a short course of SD in mice. Surgical relevance Worldwide, enhanced recovery programmes have developed into standards of care that reduce major complications after surgery, such as surgical-site infections and anastomotic leak. A complementary effort termed prehabilitation includes preoperative approaches such as smoking cessation, exercise and dietary modification. This study investigated whether a short course of dietary prehabilitation in the form of a low-fat/high-fibre composition can reverse the adverse effect of a high-fat Western-type diet on anastomotic healing in mice. Intake of a Western-type diet had a major adverse effect on both the intestinal microbiome and anastomotic healing following colonic anastomosis in mice. This could be reversed when mice received a low-fat/high-fibre diet before operation. Taken together, these data suggest that dietary modifications before major surgery can improve surgical outcomes via their effects on the intestinal microbiome.

Does intra-operative flexible endoscopy reduce anastomotic complications following left-sided colonic resections? A systematic review and meta-analysis

AIM

Postoperative anastomotic leakage (AL) or bleeding (AB) significantly impacts on patient outcome following colorectal resection. To minimize such complications, surgeons can utilize different techniques perioperatively to assess anastomotic integrity. We aim to assess published anastomotic complication rates following left-sided colonic resection, comparing the use of intra-operative flexible endoscopy (FE) against conventional tests used to assess anastomotic integrity.

METHODS

PubMed/MEDLINE and Embase online databases were searched for non-randomized and randomized case-control studies that investigated postoperative AL and/or AB rates in left-sided colonic resections, comparing intra-operative FE against conventional tests. Data from eligible studies were pooled, and a meta-analysis using Review Manager 5.3 software was performed to assess for differences in AL and AB rates.

RESULTS

Data from six studies were analysed to assess the impact of FE on postoperative AL and AB rates (1084 and 751 patients respectively). Use of FE was associated with reduced postoperative AL and AB rates, from 6.9% to 3.5% and 5.8% to 2.4% respectively. Odds ratios favoured intra-operative FE: 0.37 (95% CI 0.21-0.68, P = 0.001) for AL and 0.35 (95% CI 0.15-0.82, P = 0.02) for AB.

CONCLUSION

This meta-analysis showed that the use of intra-operative FE is associated with a reduced rate of postoperative AL and AB, compared to conventional anastomotic testing methods.

Reducing anastomotic leak in colorectal surgery: The old dogmas and the new challenges

Anastomotic leak (AL) constitutes a significant issue in colorectal surgery, and its incidence has remained stable over the last years. The use of intra-abdominal drain or the use of mechanical bowel preparation alone have been proven to be useless in preventing AL and should be abandoned. The role or oral antibiotics preparation regimens should be clarified and compared to other routes of administration, such as the intravenous route or enema. In parallel, preoperative antibiotherapy should aim at targeting collagenase-inducing pathogens, as identified by the microbiome analysis. AL can be further reduced by fluorescence angiography, which leads to significant intraoperative changes in surgical strategies. Implementation of fluorescence angiography should be encouraged. Progress made in AL comprehension and prevention might probably allow reducing the rate of diverting stoma and conduct to a revision of its indications.

Preventive strategies for anastomotic leakage after colorectal resections: A review

Anastomosis is a crucial step in radical cancer surgery. Despite being a daily practice in gastrointestinal surgery, anastomotic leakage (AL) stands as a frequent postoperative complication. Because of increased morbidity, mortality, combined with longer hospital stay, the rate of re-intervention, and poor oncological outcomes, AL is considered the most feared and life-threatening complication after colorectal resections. Furthermore, poor functional outcomes with a higher rate of a permeant stoma in 56% of patients this could negatively affect the patient’s quality of life. This a narrative review which will cover intraoperative anastomotic integrity assessment and preventive measures in order to reduce AL. Although the most important prerequisites for the creation of anastomosis is well-perfused and tension-free anastomosis, surgeons have proposed several preventive measures, which were assumed to reduce the incidence of AL, including antibiotic prophylaxis, intraoperative air leak test, omental pedicle flap, defunctioning stoma, pelvic drain insertion, stapled anastomosis, and general surgical technique. However, lack of clear evidence of which preventive measures is superior over the other combined with the fact that the decision remains based on the surgeon’s choice. Despite the advances in surgical techniques, AL remains a serious health problem associated with increased morbidity, mortality with additional cost. Many preventative measures were employed with no clear evidence supporting the superiority of stapled anastomosis over hand-Sewn anastomosis, coating of the anastomosis, or pelvic drain. Defunctioning stoma, when justified it could decrease the leakage-related complications and the incidence of reoperation. MBP combined with oral antibiotics still recommended.

The Risk Factor of Anastomotic Hypoperfusion in Colorectal Surgery

BACKGROUND

Inadequate blood flow is an important risk factor for anastomotic leakage. Indocyanine green (ICG) fluorescence imaging allows intraoperative assessment of intestinal blood flow. This study determined the risk factor of anastomotic hypoperfusion in colorectal surgery using ICG fluorescence imaging.

METHODS

This study included 74 consecutive patients who underwent colorectal surgery between April 2017 and March 2018. ICG was injected intravenously after dividing the mesentery and central vessels along the planned transection line, but before completing the anastomosis. Intraoperative blood flow was evaluated using ICG fluorescence imaging. With regard to the patient-, tumor-, and surgery-related factors, anastomotic perfusion was evaluated based on the changed transection line and prolonged (more than 60 s) perfusion time.

RESULTS

Intraoperative ICG fluorescence imaging was performed in all patients, and no adverse events were associated with ICG injection. Based on the perfusion assessment, we changed the transection line in six patients (8.1%). The prolonged perfusion time was observed in nine patients (12.2%). The postoperative course was uneventful in 63 (85.1%) patients, but one patient (1.4%) had postoperative anastomotic leakage. The changed transection line was significantly associated with anticoagulation therapy (P = 0.029). Well-known risk factors, including surgical site, sex, smoking, blood loss, operative time, and preoperative chemoradiotherapy, were not related to the changed transection line. Prolonged ICG perfusion time was not associated with any patient-, tumor-, or surgery-related factors.

CONCLUSIONS

The evaluation of intraoperative blood flow using ICG fluorescence imaging may be able to detect anastomotic hypoperfusion, and anticoagulation therapy is a risk factor of anastomotic hypoperfusion in colorectal surgery.

The Association of Coloproctology of Great Britain and Ireland consensus guidelines in surgery for inflammatory bowel disease

AIM

There is a requirement of an expansive and up to date review of surgical management of inflammatory bowel disease (IBD) that can dovetail with the medical guidelines produced by the British Society of Gastroenterology.

METHODS

Surgeons who are members of the ACPGBI with a recognised interest in IBD were invited to contribute various sections of the guidelines. They were directed to produce a procedure based document using literature searches that were systematic, comprehensible, transparent and reproducible. Levels of evidence were graded. An editorial board was convened to ensure consistency of style, presentation and quality. 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 2 votes were included in the guidelines.

RESULTS

All aspects of surgical care for IBD have been included along with 157 recommendations for management.

CONCLUSION

These guidelines provide an up to date and evidence based summary of the current surgical knowledge in the management of IBD and will serve as a useful practical text for clinicians performing this type of surgery.

Risk Factors and Oncologic Outcomes of Anastomosis Leakage After Laparoscopic Right Colectomy

PURPOSE

We estimated the incidence of anastomosis leakage and explore possible risk factors and oncologic outcomes following laparoscopic right-side colon resection among colon cancer patients.

MATERIALS AND METHODS

We retrospectively analyzed 423 patients who were diagnosed with appendiceal, cecal, ascending, or hepatic flexure colon cancer who underwent laparoscopic colonic resection and anastomosis between September 2006 and July 2014. We compared short-term and long-term outcomes between no-leakage and leakage groups.

RESULTS

There were 16 cases of right-side anastomosis leakage in a total 423 colon cancer cases (3.78%). The risk of leakage was increased in smokers (odds ratio=6.592, P=0.007) and with a longer operating time (odds ratio=1.024, P<0.001). There were no significant differences between the groups in local recurrence (P=0.106), overall survival (P=0.055), or cancer-specific survival (P=0.235).

CONCLUSIONS

Smoking and long operating time are risk factors for right-side colon anastomosis. There were no significant differences in oncologic outcomes.

IntAct: intra-operative fluorescence angiography to prevent anastomotic leak in rectal cancer surgery: a randomized controlled trial

AIM

Anastomotic leak (AL) is a major complication of rectal cancer surgery. Despite advances in surgical practice, the rates of AL have remained static, at around 10-15%. The aetiology of AL is multifactorial, but one of the most crucial risk factors, which is mostly under the control of the surgeon, is blood supply to the anastomosis. The MRC/NIHR IntAct study will determine whether assessment of anastomotic perfusion using a fluorescent dye (indocyanine green) and near-infrared laparoscopy can minimize the rate of AL leak compared with conventional white-light laparoscopy. Two mechanistic sub-studies will explore the role of the rectal microbiome in AL and the predictive value of CT angiography/perfusion studies.

METHOD

IntAct is a prospective, unblinded, parallel-group, multicentre, European, randomized controlled trial comparing surgery with intra-operative fluorescence angiography (IFA) against standard care (surgery with no IFA). The primary end-point is rate of clinical AL at 90 days following surgery. Secondary end-points include all AL (clinical and radiological), change in planned anastomosis, complications and re-interventions, use of stoma, cost-effectiveness of the intervention and quality of life. Patients should have a diagnosis of adenocarcinoma of the rectum suitable for potentially curative surgery by anterior resection. Over 3 years, 880 patients from 25 European centres will be recruited and followed up for 90 days.

DISCUSSION

IntAct will rigorously evaluate the use of IFA in rectal cancer surgery and explore the role of the microbiome in AL and the predictive value of preoperative CT angiography/perfusion scanning.

Neopterin, kynurenine and tryptophan as new biomarkers for early detection of rectal anastomotic leakage

Introduction

At present, there are no strong predictors, nor a useful scoring system, that clearly identifies patients at risk for anastomotic leakage.

Aim

This study aimed to investigate a new method that assesses this risk by monitoring levels of neopterin, tryptophan, and kynurenine, in bodily fluids.

Material and methods

This prospective study included patients who underwent elective rectal resection for carcinoma. The basic condition for inclusion was rectal anastomosis using the double-stapling technique. Preoperative levels of neopterin, tryptophan, kynurenine, and their ratios, were assessed with blood and urine samples. These levels were then monitored for 6 postoperative days in venous blood, urine, and abdominal drainage fluid.

Results

A total of 42 patients were enrolled in the study. Thirty-six patients underwent a laparoscopic resection and 6 patients had an open procedure. No differences were found among neopterin, tryptophan, and kynurenine serum levels. However, the groups were observed to have significant differences in the urinary neopterin/creatinine ratio: the preoperative neopterin/creatinine ratio was 139.5 μmol/mol in the group with leakage, vs 114.8 μmol/mol in the group without complications, p = 0.037. The same results were observed during the postoperative period, p = 0.012. Additionally, the group with complications had a higher mean value of neopterin in drainage fluid, p = 0.048.

Conclusions

Our study demonstrated that high preoperative levels of urinary neopterin could be interpreted as a risk for anastomotic leakage. Moreover, pathological levels of neopterin in urine and abdominal drainage fluid could be useful for early identification of anastomotic leakage during the postoperative period prior to its clinical development.

Serum cytokines in early prediction of anastomotic leakage following low anterior resection

Introduction

Anastomotic leakage continues to be one of the most serious complications following low anterior resections. Early diagnosis of a leak is difficult but critical to minimize morbidity and mortality.

Aim

To evaluate changes in serum concentrations of 27 different cytokines following low anterior resection, with the goal of finding new, early biomarkers of anastomotic leak.

Material and methods

This is a prospective observational study that includes 32 patients undergoing elective low anterior resection for rectal cancer. Blood samples were collected preoperatively and on postoperative day 3.

Results

Five patients developed anastomotic leak (15%). On postoperative day 3, high-sensitivity C-reactive protein (hs-CRP), interleukin (IL)-6, and regulated on activation, normal T cell expressed and secreted (RANTES) were significantly higher in patients with anastomotic leak, while IL-9 and fibroblast growth factor (FGF) 2 were significantly lower. Analysis of relative changes in the concentration of cytokines from preoperative to postoperative day 3 revealed a significant increase of IL-6 and granulocyte-colony stimulating factor (G-CSF) in patients with an anastomotic leak. Upon receiver operating curve (ROC) analysis, the performance of hs-CRP was found to be excellent (AUC = 0.99), and performance of ΔIL-6, IL-6, RANTES, and FGF2 was good (AUC: 0.81–0.87). Patients who developed an anastomotic leak preoperatively had significantly lower levels of macrophage inflammatory protein-1 α (MIP-1α), monocyte chemotactic protein-1 (MCP-1), IL-8, FGF2, and G-CSF.

Conclusions

The single most accurate serum biomarker of anastomotic leakage continues to be hs-CRP. However, when analyzing relative changes of cytokine levels, ΔIL-6 appears to be a better leak predictor than CRP.

Intraoperative use of ICG fluorescence imaging to reduce the risk of anastomotic leakage in colorectal surgery: a systematic review and meta-analysis

BACKGROUND

Indocyanine green (ICG) fluorescence imaging has been proven to be an effective tool to assess anastomotic perfusion. The aim of this systematic review and meta-analysis was to evaluate its efficacy in reducing the anastomotic leakage (AL) rate after colorectal surgery.

METHODS

PubMed, Scopus, WOS, Google Scholar and Cochrane Library were searched up to January 2017 for studies comparing fluorescence imaging with standard care. ClinicalTrials.gov register was searched for ongoing trials. The primary outcome measure was AL rate with at least 1 month of follow-up. ROBINS-I tool was used for quality assessment. A meta-analysis with random-effects model was performed to calculate odds ratios (ORs) from the original data.

RESULTS

One thousand three hundred and two patients from 5 non-randomized studies were included. Fluorescence imaging significantly reduced the AL rate in patients undergoing surgery for colorectal cancer (OR 0.34; CI 0.16-0.74; p = 0.006). Low AL rates were shown in rectal cancer surgery (ICG 1.1% vs non-ICG 6.1%; p = 0.02). There was no significant decrease in the AL rate when colorectal procedures for benign and malignant disease were combined. To date, there are no published randomized control trials (RCTs) on this subject, though 3 ongoing RCTs were identified.

CONCLUSIONS

ICG fluorescence imaging seems to reduce AL rates following colorectal surgery for cancer. However, the inherent bias of the non-randomized studies included, and their differences in AL definition and diagnosis could have influenced results. Large well-designed RCTs are needed to provide evidence for its routine use in colorectal surgery.

Colorectal anastomotic leak: delay in reintervention after false-negative computed tomography scan is a reason for concern

BACKGROUND

Early detection of anastomotic leakage (AL) after colorectal surgery followed by timely reintervention is of crucial importance. The aim of this study was to investigate the accuracy of computed tomography (CT) imaging for AL and the effects of delay in reintervention after a false-negative CT.

METHODS

All files from patients who had colorectal surgery with primary anastomoses between 2009 and 2014 were reviewed. The predictive value of CT scanning for AL was determined and correlated with short-term postoperative patient outcomes. In addition, factors predictive of false-negative scans were assessed.

RESULTS

Six hundred and twenty-eight patient files were reviewed. In total, a CT scan was performed in 127 patients. Overall, leakage was seen in 49 patients (7.8%). The positive and negative predictive values were 78 and 88%, respectively. Sensitivity was 73% and specificity 91%. In patients with a true-positive CT (n = 24), reintervention followed after a median interval of 0 days (IQR 1), whereas this was 1 day (IQR 2) in the false-negative group (n = 11) (p < 0.05). This was associated with a significantly increased mortality rate (1/24 = 4.2% vs 5/11 = 45.5%) (p < 0.005), an increased length of hospital stay [median 28 days (IQR 26) vs 54 days (IQR 20) (p < 0.05)].

CONCLUSIONS

Delayed reintervention after false-negative CT scanning is associated with a high mortality rate and a significant increase in length of hospital stay.

Inflammatory markers as early predictors of infection after colorectal surgery: the same cut-off values in laparoscopy and laparotomy?

PURPOSE

C-reactive protein and procalcitonin are reliable early predictors of infection after colorectal surgery. However, the inflammatory response is lower after laparoscopy as compared to open surgery. This study analyzed whether a different cutoff value of inflammatory markers should be chosen according to the surgical approach.

METHODS

A prospective, observational study included consecutive patients undergoing elective colorectal surgery in three academic centers. All infections until postoperative day (POD) 30 were recorded. The inflammatory markers were analyzed daily until POD 4. Areas under the ROC curve and diagnostic values were calculated in order to assess their accuracy as a predictor of intra-abdominal infection.

RESULTS

Five-hundred-one patients were included. The incidence of intra-abdominal infection was 11.8%. The median levels of C-reactive protein (CRP) and procalcitonin (PCT) were lower in the laparoscopy group at each postoperative day (p < 0.0001). In patients without intra-abdominal infection, they were also lower in the laparoscopy group (p = 0.0036) but were not different in patients presenting with intra-abdominal infections (p = 0.3243). In the laparoscopy group, CRP at POD 4 was the most accurate predictor of overall and intra-abdominal infection (AUC = 0.775). With a cutoff of 100 mg/L, it yielded 95.7% negative predictive value, 75% sensitivity, and 70.3% specificity for the detection of intra-abdominal infection.

CONCLUSION

The impact of infection on inflammatory markers is more important than that of the surgical approach. Defining a specific cutoff value for early discharge according to the surgical approach is not justified. A patient with CRP values lower than 100 mg/L on POD 4 can be safely discharged.

Diagnostic Accuracy of Procalcitonin and C-reactive Protein for the Early Diagnosis of Intra-abdominal Infection After Elective Colorectal Surgery: A Meta-analysis

OBJECTIVE

Intra-abdominal infections (IAIs) after elective colorectal surgery impact significantly the short- and long-term outcomes. In the era of fast-track surgery, they often come to light after discharge from hospital. Early diagnosis is therefore essential. C-reactive protein levels have proved to be accurate in this setting. Procalcitonin has been evaluated in several studies with conflicting results. This meta-analysis aimed to compare the predictive abilities of C-reactive protein and procalcitonin in the occurrence of IAIs after elective colorectal surgery.

METHODS

This meta-analysis included studies analyzing C-reactive protein and/or procalcitonin levels at postoperative days 2, 3, 4, and/or 5 as markers of intra-abdominal infection after elective colorectal surgery. Methodological quality was assessed by the QUADAS2 tool. The area under the curve summary receiver-operating characteristic was calculated for each day and each biomarker, using a random-effects model in cases of heterogeneity.

RESULTS

The meta-analysis included 11 studies (2692 patients). An IAI occurred in 8.9% of the patients. On postoperative day 3, area under the curve was 0.80 (95% CI, 0.76-0.85) for C-reactive protein and 0.78 (95% CI, 0.68-0.87) for procalcitonin. On postoperative day 5, their predictive accuracies were 0.87 (95% CI, 0.80-0.93) and 0.90 (95% CI, 0.82-0.98), respectively. The accuracy of C-reactive protein and procalcitonin did not differ at any postoperative day.

CONCLUSIONS

Levels of inflammatory markers under the cutoff value between postoperative days 3 and 5 ensure safe early discharge after elective colorectal surgery. Procalcitonin seems not to have added value as compared to C-reactive protein in this setting.

Diagnosis, treatment, and consequences of anastomotic leakage in colorectal surgery

PURPOSE

The aim of this study was to explore the choice of modality for diagnosis, treatments, and consequences of anastomotic leakage.

METHODS

This is a retrospective study of consecutive patients who underwent surgery that included a colorectal anastomosis due to colorectal cancer, diverticulitis, inflammatory bowel disease (IBD), or benign polyps.

RESULTS

A total of 600 patients were included during 2010-2012, and 60 (10%) had an anastomotic leakage. It took in mean 8.8 days (range 2-42) until the anastomotic leakage was diagnosed. A total of 44/60 of the patients with a leakage had a CT scan of the abdomen; 11 (25%) were initially negative for anastomotic leakage. Among all leakages, the anastomosis was taken down in 45 patients (76.3%). All patients with a grade B leakage (n = 6) were treated with antibiotics, and two also received transanal drainage. The overall complication rate was also significantly higher in those with leakage (93.3 vs. 28.5%, p < 0.001), and it was more common with more than three complications (70 vs. 1.5%, p < 0.001). There was a higher mortality in the leakage group.

CONCLUSION

This study demonstrated that one fourth of the CT scans that were executed were initially negative for leakage. Most patients with a grade C leakage will not have an intact anastomosis. An anastomotic leakage leads to significantly more severe postoperative complications, higher rate of reoperations, and higher mortality. An earlier relaparotomy instead of a CT scan and improved postoperative surveillance could possibly reduce the consequences of the anastomotic leakage.

A collaborative review of the current concepts and challenges of anastomotic leaks in colorectal surgery

The reduction of the incidence, detection and treatment of anastomotic leakage (AL) continues to challenge the colorectal surgical community. AL is not consistently defined and reported in clinical studies, its occurrence is variably reported and its impact on longterm morbidity and health-care resources has received relatively little attention. Controversy continues regarding the best strategies to reduce the risk. Diagnostic tests lack sensitivity and specificity, resulting in delayed diagnosis and increased morbidity. Intra-operative fluorescence angiography has recently been introduced as a means of real-time assessment of anastomotic perfusion and preliminary evidence suggests that it may reduce the rate of AL. In addition, concepts are emerging about the role of the rectal mucosal microbiome in AL and the possible role of new prophylactic therapies. In January 2016 a meeting of expert colorectal surgeons and pathologists was held in London, UK, to identify the ongoing controversies surrounding AL in colorectal surgery. The outcome of the meeting is presented in the form of research challenges that need to be addressed.

Diagnostic Accuracy of Inflammatory Markers As Early Predictors of Infection After Elective Colorectal Surgery: Results From the IMACORS Study

BACKGROUND

Intra-abdominal infections are frequent and life-threatening complications after colorectal surgery. An early detection could diminish their clinical impact and permit safe early discharge.

OBJECTIVE

This study aimed to find the most accurate marker for the detection of postoperative intra-abdominal infection and the appropriate moment to measure it.

METHODS

A prospective, observational study was conducted in 3 centers. Consecutive patients undergoing elective colorectal surgery with anastomosis were included. C-reactive protein and procalcitonin were measured daily until the fourth postoperative day. Postoperative infections were recorded according to the definitions of the Centres for Diseases Control. The areas under the receiver operating characteristic curve were analyzed and compared to assess the diagnostic accuracy of each marker.

RESULTS

Five-hundred and one patients were analyzed. The incidence of intra-abdominal infection was 11.8%, with 24.6% of patients presenting at least one infectious complication. Overall mortality was 1.2%. At the fourth postoperative day, C-reactive protein was more discriminating than procalcitonin for the detection of intra-abdominal infection (areas under the ROC curve: 0.775 vs 0.689, respectively, P = 0.03). Procalcitonin levels showed wide dispersion. For the detection of all infectious complications, C-reactive protein was also significantly more accurate than procalcitonin on the fourth postoperative day (areas under the ROC curve: 0.783 vs 0.671, P = 0.0002).

CONCLUSIONS

C-reactive protein is more accurate than procalcitonin for the detection of infectious complications and should be systematically measured at the fourth postoperative day. It is a useful tool to ensure a safe early discharge after elective colorectal surgery.

Is Early Reversal of Defunctioning Ileostomy a Shorter, Easier and Less Expensive Operation?

BACKGROUND

A defunctioning loop ileostomy mitigates the consequences of anastomotic leak from low rectal anastomosis but it is associated with significant morbidity. In this study, the outcome of early reversal of defunctioning ileostomy during the same admission with the primary operation was assessed.

METHODS

This randomized study was carried out at York Teaching Hospital during the period 2003-2007. All patients with defunctioning ileostomy were considered for an early second operation if they had an uneventful recovery and were in good general condition. Patients on steroids, at high cardiorespiratory risk and those experiencing any postoperative complication were excluded. Eligible patients with satisfactory gastrografin enema on postoperative day 6 were randomized to early versus late reversal at 6-8 weeks. Outcome measures were ease of closure as assessed by a visual analog scale by the operating surgeon, all postoperative complications, duration of the operation, total length of hospital stay and associated costs.

RESULTS

Thirty-nine consecutive patients were assessed for eligibility and finally 26 were included in the study. Sixteen patients underwent early reversal. The median(interquartile range (IQR)) age was 62(22) years. Early reversal was significantly superior in terms of ease of abdominal wall closure, ease of reversal (p < 0.01 each), duration of the operation (median(IQR) 20(13) vs. 40(9) min, p < 0.01) and costs of stoma care (median(IQR) 27(9) vs. 311(108) £, p < 0.01). There were no major (grade III/IV) complications in either group. Total length of hospital stay was similar between groups.

CONCLUSION

In carefully selected patients, early reversal of defunctioning ileostomy is feasible, technically easier and has shorter operative time which can also lead to significant cost savings.

Predicting colorectal surgical complications using heterogeneous clinical data and kernel methods

OBJECTIVE

In this work, we have developed a learning system capable of exploiting information conveyed by longitudinal Electronic Health Records (EHRs) for the prediction of a common postoperative complication, Anastomosis Leakage (AL), in a data-driven way and by fusing temporal population data from different and heterogeneous sources in the EHRs.

MATERIAL AND METHODS

We used linear and non-linear kernel methods individually for each data source, and leveraging the powerful multiple kernels for their effective combination. To validate the system, we used data from the EHR of the gastrointestinal department at a university hospital.

RESULTS

We first investigated the early prediction performance from each data source separately, by computing Area Under the Curve values for processed free text (0.83), blood tests (0.74), and vital signs (0.65), respectively. When exploiting the heterogeneous data sources combined using the composite kernel framework, the prediction capabilities increased considerably (0.92). Finally, posterior probabilities were evaluated for risk assessment of patients as an aid for clinicians to raise alertness at an early stage, in order to act promptly for avoiding AL complications.

DISCUSSION

Machine-learning statistical model from EHR data can be useful to predict surgical complications. The combination of EHR extracted free text, blood samples values, and patient vital signs, improves the model performance. These results can be used as a framework for preoperative clinical decision support.

Early Diagnosis of Colonic Anastomotic Leak With Peritoneal Endoscopy

Background and Objectives:

At present, we do not have a reliable method for the early diagnosis of colorectal anastomotic leakage (AL). We tested peritoneal flexible endoscopy through a port placed in the abdominal wall in the early postoperative course, as a new diagnostic method for detection of this complication and evaluated the suggested method for safety, feasibility, and accuracy.

Methods:

Ten swine were randomized into 2 groups: group A, colorectal anastomosis without leakage; and group B, colorectal anastomosis with leakage. A button gastrostomy feeding tube was inserted percutaneously into the peritoneal cavity. Colorectal anastomosis (with or without defect) was created 48 hours after the first operation. The swine were examined by peritoneal flexible endoscopy 8 and 24 hours after the colonic operation, by a consultant surgeon who was blinded to both the presence and the allocated location of the of the anastomotic defect.

Results:

None of the animals showed signs of illness 48 hours after the intraperitoneal gastrostomy tube placement. More than half of the anastomosis circumference was identified in 60 and 10% of the animals at endoscopy 8 and 24 hours, respectively, after the anastomosis was created. Excessive adhesion formation was observed in all animals, irrespective of AL. The sensitivity and specificity of endoscopy in detecting peritonitis 24 hours after AL were both 60%.

Conclusions:

Peritoneal endoscopy is a safe and simple procedure. Visualization of the peritoneal cavity in the early postoperative course was limited due to adhesion formation. Further studies are needed to clarify the accuracy of the procedure and to address additional methodological concerns.

Contemporary management of anastomotic leak after colon surgery: assessing the need for reoperation

BACKGROUND

We sought to investigate contemporary management of anastomosis leakage (AL) after colonic anastomosis.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database 2012 to 2013 was used to identify patients with AL. Multivariate regression analysis was performed to find predictors of the need for surgical intervention in management of AL.

RESULTS

A total of 32,280 patients underwent colon resection surgery with 1,240 (3.8%) developing AL. Overall, 43.9% of patients with AL did not require reoperation. Colorectal anastomosis had significantly higher risk of AL compared with ileocolonic anastomosis (adjusted odds ratio [AOR], 1.20; P = .04). However, the rate of need for reoperation was higher for AL in colocolonic anastomosis compared with ileocolonic anastomosis (AOR, 1.48; P = .04). White blood cell count (AOR, 1.07; P < .01), the presence of intra-abdominal infection with leakage (AOR, 1.47; P = .01), and protective stoma (AOR, .43, P = .02) were associated with reoperation after AL.

CONCLUSIONS

Nonoperative treatment is possible in almost half of the patients with colonic AL. The anatomic location of the anastomosis impacts the risk of AL. Severity of leakage, the presence of a stoma, and general condition of patients determine the need for reoperation.

Malpractice in colorectal surgery: a review of 122 medicolegal cases

BACKGROUND

Medical malpractice has become a rising concern for physicians, affecting the cost and delivery of health care. Colorectal procedures account for 24% of all general surgery cases, a high-risk specialty, with 15% of its physicians facing malpractice suit annually.

METHODS

The Westlaw legal database was used to identify colorectal malpractice cases.

RESULTS

In all, 122 of 230 lawsuits were included in this study. A majority of 65.6% were physician verdicts, 19.7% plaintiff verdicts, and 14.8% reached a settlement. Plaintiff payments were found to be significantly higher than settlement awards. The most common cause of alleged malpractice was failure to recognize a complication in a timely manner (45.1%), followed by damage to surrounding tissues (36.1%).

CONCLUSIONS

The most common cause of alleged malpractice was failure to recognize a complication in a timely manner, followed by damage to surrounding tissue. Plaintiff awards were significantly higher than settlement payments. It is important to understand the mechanism of malpractice allegations to better prevent litigation and improve patient care.

Anastomotic leakage after colorectal surgery: diagnostic accuracy of CT

OBJECTIVES

To evaluate the diagnostic accuracy of CT in postoperative colorectal anastomotic leakage (AL).

METHODS

Two independent blinded radiologists reviewed 153 CTs performed for suspected AL within 60 days after surgery in 131 consecutive patients, with (n = 58) or without (n = 95) retrograde contrast enema (RCE). Results were compared to original interpretations. The reference standard was reoperation or consensus (a radiologist and a surgeon) regarding clinical, laboratory, radiological, and follow-up data after medical treatment.

RESULTS

AL was confirmed in 34/131 patients. For the two reviewers and original interpretation, sensitivity of CT was 82 %, 87 %, and 71 %, respectively; specificity was 84 %, 84 %, and 92 %. RCE significantly increased the positive predictive value (from 40 % to 88 %, P = 0.0009; 41 % to 92 %, P = 0.0016; and 40 % to 100 %, P = 0.0006). Contrast extravasation was the most sensitive (reviewers, 83 % and 83 %) and specific (97 % and 97 %) sign and was significantly associated with AL by univariate analysis (P < 0.0001 and P < 0.0001). By multivariate analysis with recursive partitioning, CT with RCE was accurate to confirm or rule out AL with contrast extravasation.

CONCLUSIONS

CT with RCE is accurate for diagnosing postoperative colorectal AL. Contrast extravasation is the most reliable sign. RCE should be performed during CT for suspected AL.

KEY POINTS

• CT accurately diagnosed clinically suspected colorectal AL and showed good interobserver agreement • Contrast extravasation was the most sensitive and specific CT sign • Retrograde contrast enema during CT improved positive predictive value • Retrograde contrast enema decreased false-negative or indeterminate original CT interpretations.

C-reactive protein is a predictive factor of anastomotic leakage after laparoscopic colorectal cancer surgery

AIM: To evaluate the potential predictive role of C-reactive protein (CRP) in assessing anastomotic leakage after laparoscopic colorectal cancer surgery.

METHODS: We reviewed pre- and postoperative serum CRP in 124 patients who underwent laparoscopic surgery for colorectal cancer between January 2013 and January 2014. Patients with anastomotic leakage (group A, n = 17) were compared to those without (group B, n = 107). Patients with ongoing infections before surgery or with acquired infections other than leakage were excluded. Mean pre- and postoperative values of CRP were compared.

RESULTS: The average values of serum CRP were significantly higher in group A than in group B starting from the 2nd postoperative day (POD) until the diagnosis of leakage (P < 0.001). The cut-off value of 80 mg/L on the 3rd POD maximized the sensitivity (77%) and specificity (98%) of serum CRP in assessing the risk of leakage.

CONCLUSION: According to these results, an early and persistent elevation of CRP after laparoscopic surgery for colorectal cancer is a marker of anastomotic leakage. A cut-off value > 80 mg/L on POD3 maximizes sensitivity and specificity.

Systematic review of preoperative, intraoperative and postoperative risk factors for colorectal anastomotic leaks

BACKGROUND

Anastomotic leak (AL) represents a dreaded complication following colorectal surgery, with a prevalence of 1-19 per cent. There remains a lack of consensus regarding factors that may predispose to AL and the relative risks associated with them. The objective was to perform a systematic review of the literature, focusing on the role of preoperative, intraoperative and postoperative factors in the development of colorectal ALs.

METHODS

A systematic review was performed to identify adjustable and non-adjustable preoperative, intraoperative and postoperative factors in the pathogenesis of AL. Additionally, a severity grading system was proposed to guide treatment.

RESULTS

Of 1707 papers screened, 451 fulfilled the criteria for inclusion in the review. Significant preoperative risk factors were: male sex, American Society of Anesthesiologists fitness grade above II, renal disease, co-morbidity and history of radiotherapy. Tumour-related factors were: distal site, size larger than 3 cm, advanced stage, emergency surgery and metastatic disease. Adjustable risk factors were: smoking, obesity, poor nutrition, alcohol excess, immunosuppressants and bevacizumab. Intraoperative risk factors were: blood loss/transfusion and duration of surgery more than 4 h. Stomas lessen the consequences but not the prevalence of AL. In the postoperative period, CT is the most commonly used imaging tool, with or without rectal contrast, and a C-reactive protein level exceeding 150 mg/l on day 3-5 is the most sensitive biochemical marker. A five-level classification system for AL severity and appropriate management is presented.

CONCLUSION

Specific risk factors and their potential correction or indications for stoma were identified. An AL severity score is proposed to aid clinical decision-making.

Outcomes of the use of fully covered esophageal self-expandable stent in the management of colorectal anastomotic strictures and leaks

Introduction. Colorectal anastomotic leak or stricture is a dreaded complication leading to significant morbidity and mortality. The novel use of self-expandable metal stents (SEMS) in the management of postoperative colorectal anastomotic leaks or strictures can avoid surgical reintervention. Methods. Retrospective study with particular attention to the indications, operative or postoperative complications, and clinical outcomes of SEMS placement for patients with either a colorectal anastomotic stricture or leak. Results. Eight patients had SEMS (WallFlex stent) for the management of postoperative colorectal anastomotic leak or stricture. Five had a colorectal anastomotic stricture and 3 had a colorectal anastomotic leak. Complete resolution of the anastomotic stricture or leak was achieved in all patients. Three had recurrence of the anastomotic stricture on 3-month flexible sigmoidoscopy follow-up after the initial stent was removed. Two of these patients had a stricture that was technically too difficult to place another stent. Stent migration was noted in 2 patients, one at day 3 and the other at day 14 after stent placement that required a larger 23 mm stent to be placed. Conclusions. The use of SEMS in the management of colorectal anastomotic leaks or strictures is feasible and is associated with high technical and clinical success rate.

Clinical endpoint, early detection, and differential diagnosis of postoperative ileus: a systematic review of the literature

BACKGROUND

This systematic review summarizes evidence regarding clinical endpoints, early detection, and differential diagnosis of postoperative ileus (POI).

METHODS

Using MEDLINE, EMBASE, Cochrane, and Web-of-Science, we identified 2,084 articles. Risk of bias and level of evidence (LOE) of the included articles were determined, and relevant results were summarized.

RESULTS

Eleven articles were included, most of which with substantial risks of bias. Bowel motility studies revealed that defecation together with solid food tolerance is the most representative clinical endpoint of POI (LOE: 2b); other clinical signs (e.g. bowel sounds, passage of flatus) did not correlate with a full recovery of bowel motility. Inflammatory parameters including interleukin (IL)-6, IL-1, and TNF-α might assist in an early detection of prolonged POI (LOE: 4). Clinical manifestations (e.g. nausea, vomiting, abdominal distension, bowel sounds, flatus) and X-ray examinations provided limited aid to the differential diagnosis of POI, while CT with Gastrografin had the best specificity and sensitivity (both 100%; LOE: 1c).

CONCLUSIONS

Postoperative defecation together with tolerance of solid food intake seems to be the best clinical endpoint of POI. CT has the best differential diagnostic value between POI and other complications. Prospective studies with a high LOE are in great need.

Diagnosis, management and outcome of early anastomotic leakage following colorectal anastomosis using a compression device: is it different?

AIM

Compression anastomosis has proved to be safe for rectal reconstruction with leak rates comparable to those observed using circular stapling devices. However, there are no data on whether the metallic compression ring alters the ease of diagnosis or the treatment in cases of leakage. In this study, we present our experience with early leakage following compression anastomosis.

METHOD

A prospective registry was used for data review. Patients with anastomotic leakage following compression anastomosis between November 2008 and September 2013 were included.

RESULTS

In all, 197 (92 female) patients were operated using a novel compression device. Early leakage was found in 10 (5.1%) patients after a median of 5 (3-14) days. The radiologist was able to detect leakage using CT in nine out of 10 cases unequivocally. Removal of the ring was necessary in eight of the 10 cases, and salvage of the anastomosis was feasible on six occasions. In all diverted cases with a low anastomosis, a transanal repair of the defect was feasible in three cases, including a single patient with complete separation of the anastomosis.

CONCLUSION

Artefacts on the CT scan caused by the compression ring did not hamper the diagnosis of anastomotic leakage. Removal of the ring in the early postoperative period is not associated with complete separation of the bowel ends. Salvage of anastomosis is feasible in most cases.

Use of a modified Delphi approach to develop research priorities for the association of coloproctology of Great Britain and Ireland

AIM

The modified Delphi approach is an established method for reaching a consensus opinion among a group of experts in a particular field. We have used this technique to survey the entire membership of the Association of Coloproctology of Great Britain and Ireland (ACPGBI) to reach a consensus on prioritizing clinical research questions in colorectal disease.

METHOD

Three rounds of surveys were conducted using a web-based tool. In the first, the ACPGBI membership was invited to submit research questions. In Rounds 2 and 3 they were asked to score questions on priority. A steering group analysed the results of each round to identify those questions ranked as being of highest priority.

RESULTS

Five hundred and two questions were submitted in Round 1. Following two rounds of voting and analysis, a list of 25 priority questions was produced, including 15 cancer-related and 10 noncancer-related questions.

CONCLUSION

It is anticipated that these results will: (i) set the research agenda over the next few years for the study of colorectal disease in the United Kingdom, (ii) promote development and (iii) define funding of new research and prioritize areas of unmet clinical need where the potential clinical impact is greatest.

Support Vector Feature Selection for Early Detection of Anastomosis Leakage From Bag-of-Words in Electronic Health Records

The free text in electronic health records (EHRs) conveys a huge amount of clinical information about health state and patient history. Despite a rapidly growing literature on the use of machine learning techniques for extracting this information, little effort has been invested toward feature selection and the features' corresponding medical interpretation. In this study, we focus on the task of early detection of anastomosis leakage (AL), a severe complication after elective surgery for colorectal cancer (CRC) surgery, using free text extracted from EHRs. We use a bag-of-words model to investigate the potential for feature selection strategies. The purpose is earlier detection of AL and prediction of AL with data generated in the EHR before the actual complication occur. Due to the high dimensionality of the data, we derive feature selection strategies using the robust support vector machine linear maximum margin classifier, by investigating: 1) a simple statistical criterion (leave-one-out-based test); 2) an intensive-computation statistical criterion (Bootstrap resampling); and 3) an advanced statistical criterion (kernel entropy). Results reveal a discriminatory power for early detection of complications after CRC (sensitivity 100%; specificity 72%). These results can be used to develop prediction models, based on EHR data, that can support surgeons and patients in the preoperative decision making phase.

Improving the outcomes in oncological colorectal surgery

During the last several decades, colorectal cancer surgery has experienced some major perioperative improvements. Preoperative risk-assessment of nutrition, frailty, and sarcopenia followed by interventions for patient optimization or an adapted surgical strategy, contributed to improved postoperative outcomes. Enhanced recovery programs or fast-track surgery also resulted in reduced length of hospital stay and overall complications without affecting patient safety. After an initially indecisive start due to uncertainty about oncological safety, the most significant improvement in intraoperative care was the introduction of laparoscopy. Laparoscopic surgery for colon and rectal cancer is associated with better short-term outcomes, whereas long-term outcomes regarding survival and recurrence rates are comparable. Nevertheless, long-term results in rectal surgery remain to be seen. Early recognition of anastomotic leakage remains a challenge, though multiple improvements have allowed better management of this complication.