Anastomotic leaks: what is the best diagnostic imaging study?

Added value of positive intraluminal contrast CT over fluoroscopic examination for detecting gastrointestinal leakage after gastrointestinal surgery

We aimed to evaluate the added value of positive intraluminal contrast computed tomography (CT) over fluoroscopy in detecting anastomotic leakage after gastrointestinal (GI) surgery. A total of 141 GI surgery patients who underwent fluoroscopic examination and CT were included. Two radiologists reviewed the fluoroscopic images with and without CT to determine anastomotic leakage on a 5-point confidence scale and graded the leakage on a 4-point grading system. The hospital stay duration and treatment type were recorded. The radiologists' diagnostic performance in determining leakage was compared using the receiver operating characteristics analysis, and interobserver agreement was analyzed. Fifty-three patients developed GI leakage. When CT was added to the fluoroscopic images, the area under the curve (AUC) values significantly increased for both reviewers. The interobserver agreement for leakage between the two reviewers was excellent and improved with the addition of CT (weighted kappa value, 0.869 versus 0.805). Postoperative intervention was more frequently performed (P < 0.001), and patients with leakage had a significantly longer mean postoperative hospital stay (45 days vs. 27 days) (P = 0.003). Thus, positive intraluminal contrast CT provides added value over fluoroscopic examination for detecting GI leakage in patients undergoing GI tract surgery, increasing AUC values, and improving interobserver agreement.

CT scan for early diagnosis of anastomotic leak after colorectal surgery: is rectal contrast useful?

BACKGROUND

Computed tomography (CT) scan with rectal contrast enema (RCE-CT) could increase the detection rate of anastomotic leaks (AL) in the early postoperative period following colorectal surgery, compared to CT scan without RCE. The aim of this study was to assess the benefit of RCE-CT for the early diagnosis of AL following colorectal surgery.

METHODS

Patients who had a RCE-CT for suspected AL in the early postoperative period following colorectal surgery with anastomosis between January 2012 and July 2019 at the Dijon University Hospital were retrospectively included. All images were reviewed by two independent observers who were blinded to the original report. The reviewers reported for each patient whether an AL was present or not in each imaging modality (CT scan, then RCE-CT). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were then calculated to determine the diagnostic performance of each modality.

RESULTS

One hundred and thirty-nine patients were included. RCE-CT had an increased NPV compared to CT scan (82% vs 77% (p = 0.02) and 84% vs 68% (p < 0.0001) for observers 1 and 2, respectively). RCE-CT had an increased sensitivity compared to CT scan (79% vs 48% (p < 0.0001) for observer 2). RCE-CT had a significant lower false-negative rate for both observers: 18% vs 23% (p = 0.02) and 16% vs 32% (p < 0.0001).

CONCLUSIONS

RCE-CT improved the detection rates of AL in the early period following colorectal surgery. RCE-CT should be recommended when a CT scan is negative and AL is still suspected.

MRI diagnose post-operative anastomotic leak in patients with rectal cancer: preliminary experience

BACKGROUND

Anastomotic leakage (AL) is one of the most serious postoperative complications after colorectal anastomosis. This study aims to evaluate the feasibility and diagnostic accuracy of magnetic resonance imaging (MRI) in the early detection of AL in patients with clinically suspected AL after rectal anterior resection.

METHODS

This was a prospective study including patients who underwent anterior resection and postoperative MRI examination. AL was diagnosed by comprehensive indictors, which were mainly confirmed by clinical signs, symptoms, and retrograde contrast enema (RCE) radiography. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of diagnosing AL with MRI were calculated.

RESULTS

In total, 347 patients received anterior resection for rectal cancer, and 28 patients were suspected to have AL. Finally, 23 patients were included and received MRI examination. The median time interval from surgery to MRI was 10 days (3-21 days). The median distance from anastomosis to anal verge was 4.0 cm (2.0-10 cm), and 11 patients underwent diverted ileostomy. Eighteen patients had an anastomotic leak, including one patient who had a pelvic abscess and five patients who had no evidence of AL in the MRI examination. The overall sensitivity and specificity were 94.4% (95% CI 70.6% to 99.7%) and 80% (95% CI 29.8% to 98.9%), respectively. The PPV was 0.94 (95% CI 0.71 to 0.99) and the NPV was 0.80 (95% CI 0.29 to 0.99). For patients who had anastomosis less than 5 cm, the diagnostic accuracy of MRI was 93.7% (15/16). T2-weighted imaging with fat suppression can effectively reveal the leak track.

CONCLUSIONS

The accuracy of plain MRI examination in diagnosing AL was favorable for patients with a suspected AL. T2-weighted imaging with fat suppression was the best imaging modality to diagnose AL. A multicenter prospective study with more samples is needed to further determine the safety and feasibility of MRI in the diagnosis of AL.

Pictorial review: radiological diagnosis of anastomotic leakage with water-soluble contrast enema after anterior resection of the rectum

For patients who have undergone colorectal surgery, anastomotic leakage is a serious and challenging complication with a variable rate ranging between 1.8% and 19.2%. Postoperative anastomotic leaks after colorectal surgery can have severe consequences for patients, particularly ones who present with few or no symptoms. Computed tomography and/or water-soluble contrast enema (WSE) are the most frequently utilized imaging methods to identify and diagnose anastomotic leaks early. WSE is a safe and complication-free procedure that allows to identify the presence of otherwise unrecognized anastomotic leaks, both in asymptomatic and symptomatic patients. Fluoroscopic rectal examination using a water-soluble contrast agent for postoperative patients is never an easy examination to perform since it requires careful preparation, skill, and knowledge. Four morphological types of anastomotic dispersion have been described: "saccular type", "horny type", "serpentine type" and "dendritic type". Among 4 types of leakage, dendritic and serpentine types are more frequently followed by clinical symptoms and none of the dendritic type resolves spontaneously. On the other hand, the saccular and horny types have a better prognosis after healing of the loss and subsequent restoration of the ostomy as they consist of a cavity that provides a sort of physical barrier to the spread of inflammation. The aim of this pictorial essay was to illustrate the spectrum of imaging findings of morphological types of radiologic leakages on WCE in patients with colorectal surgical anastomosis. We have also tried to provide tips and tools to enable identification of radiological leakages on retrograde WCE, particularly of the smallest leaks which can be more easily missed.

Surgical Resection of Metastatic Malignant Small Bowel Obstruction

Small bowel cancer is a rare cause of small bowel obstruction (SBO) that is often discovered too late, leading to a poor prognosis at diagnosis. This case describes an African American patient with a previous history of abdominal surgery who presented to the emergency department with a partial small bowel obstruction (PSBO) that failed to resolve with conservative measures, therefore requiring surgical intervention. An exploratory laparoscopy revealed a firm apple core mass obstructing the lumen of the proximal jejunum 20 cm from the ligament of Treitz. The involved portion of the small bowel was resected with wide margins and sent to pathology. The small bowel was reconstructed by a functional end-to-end anastomosis, and the patient was admitted for observation until the return of bowel function. The pathology report, returned four weeks after the patient's discharge, reported metastatic adenocarcinoma originating from the small intestine. The patient was referred to oncology for further management of his metastatic cancer. Small bowel cancer, although rare, should always be part of the differential diagnosis in the case of small bowel obstruction. If cancer is suspected during exploratory surgery, the entire peritoneal cavity should be explored, and oncologic bowel resection should be performed with adequate margins. Final staging then occurs in the postoperative period.

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.

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.

Diagnosis of Anastomotic Leak

Anastomotic leaks after colorectal surgery is associated with increased morbidity and mortality. Understanding the impact of anastomotic leaks and their risk factors can help the surgeon avoid any modifiable pitfalls. The diagnosis of an anastomotic leak can be elusive but can be discerned by the patient's global clinical assessment, adjunctive laboratory data and radiological assessment. The use of inflammatory markers such as C-Reactive Protein and Procalcitonin have recently gained traction as harbingers for a leak. A CT scan and/or a water soluble contrast study can further elucidate the location and severity of a leak. Further intervention is then individualized on the spectrum of simple observation with resolution or surgical intervention.

Contrast-enhanced abdominal computed tomography to evaluate anastomotic integrity before ileostomy closure in postoperative colorectal cancer patients

PURPOSE

To investigate the usefulness of contrast-enhanced abdominal computed tomography (CECT) to predict clinically significant anastomotic leakage (CSAL) in patients who received colorectal cancer surgery with diverting ileostomy.

METHODS

In this retrospective cohort study, patients who underwent colorectal cancer surgery with diverting ileostomy from January 2014 to May 2018 and postoperative CECT were included. The performance of significant CECT features, identified using multivariable logistic regression, to predict CSAL was calculated. In subgroup analysis, the areas under the receiver operating characteristic curve (AUROCs) were compared between CECT and water-soluble contrast enema (WSCE) using DeLong's method.

RESULTS

Of 325 patients (median age, 58 years; 213 men), CECT was routinely performed to evaluate cancer status in 307 (94.5%), and CSAL was observed in 28 (8.6%). After multivariable adjustment, anastomotic mural defect (odds ratio [OR] 5.24; 95% confidence interval [CI] 1.77-15.51; p = 0.003), perianastomotic air (OR 7.28; 95% CI 1.82-29.17; p = 0.007) and ischemic colitis (OR 3.30; 95% CI 1.13-9.61; p = 0.029) were significantly associated with CSAL. The sensitivity, specificity, accuracy, and positive and negative predictive values of significant CECT features were 60.7%, 88.2%, 85.9%, 32.7%, and 96.0%, respectively. In subgroup analysis of 144 patients, the AUROC using significant CECT features (optimal sensitivity/specificity, 50.0%/90.4%) was comparable to that using WSCE (optimal sensitivity/specificity, 12.5%/97.8%) to predict CSAL (0.704 vs. 0.552, p = 0.085).

CONCLUSION

CECT performed after colorectal cancer surgery may be useful to assess anastomotic integrity before ileostomy closure, especially to negatively predict CSAL. In the presence of anastomotic mural defect, perianastomotic air, or ischemic colitis, WSCE may be recommended to exclude CSAL.

Serial assessment of inflammatory parameters for prediction of septic complications following surgery for colorectal endometriosis : A descriptive, retrospective study

Purpose

To assess whether C‑reactive protein (CRP), white blood cell count (WBC) and body temperature changes are suitable parameters for the early detection of septic complications following resection of colorectal deep endometriosis (DE).

Methods

Retrospective data analysis of CRP, WBC and body temperature courses following colorectal surgery for DE at a tertiary referral center for endometriosis.

Results

Out of 183 surgeries performed, 10 major surgical complications were observed, including 4 anastomotic leakages (AL 2%) and 2 rectovaginal fistulae (RVF 1%). In the presence of a lower gastrointestinal tract (GIT)-related septic complication or abdominal wall abscess, serum CRP levels were increased starting at postoperative day 2–3. A cut-off value of 10 mg/dl on day 4 for prediction of early septic complications could be verified (area under the curve 0.94, obtained by receiver operating characteristics analysis, sensitivity 88%, specificity 90%, positive predictive value 32%, negative predictive value 99%). Additionally, most patients with early septic complications exhibited increased WBC levels starting mainly from day 3–4; however, increased inflammatory parameters could not be observed in one patient with an RVF. Body temperature did not prove useful for early discrimination between uncomplicated cases and those with early septic complications.

Conclusion

Relevant elevations of serum CRP and WBC levels were demonstrated in patients with early septic complications following surgery for colorectal DE starting at postoperative day 2–4. The cut-off value of 10 mg/dl for CRP levels may serve as an early predictor for lower GIT-related septic complications but should be used with caution in women with suspected RVF development.

Supplementary Information

The online version of this article (10.1007/s00508-021-01916-w) contains supplementary material, which is available to authorized users.

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

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

Evaluation of Pelvic Anastomosis by Endoscopic and Contrast Studies Prior to Ileostomy Closure: Are Both Necessary? A Single Institution Review

Contrast enema is the gold standard technique for evaluating a pelvic anastomosis (PA) prior to ileostomy closure. With the increasing use of flexible endoscopic modalities, the need for contrast studies may be unnecessary. The objective of this study is to compare flexible endoscopy and contrast studies for anastomotic inspection prior to defunctioning stoma reversal. Patients with a protected PA undergoing ileostomy closure between July 2014 and June 2019 at our institution were retrospectively identified. Demographics and clinical outcomes in patients undergoing preoperative evaluation with endoscopic and/or contrast studies were analyzed. We identified 207 patients undergoing ileostomy closure. According to surgeon's preference, 91 patients underwent only flexible endoscopy (FE) and 100 patients underwent both endoscopic and contrast evaluation (FE + CE) prior to reversal. There was no significant difference in pelvic anastomotic leak (2.2% vs. 1%), anastomotic stricture (1.1% vs. 6%), pelvic abscess (2.2% vs. 3.0%), or postoperative anastomotic complications (4.4% vs. 9%) between groups FE and FE + CE (P > .05). Flexible endoscopy alone appears to be an acceptable technique for anastomotic evaluation prior to ileostomy closure. Further studies are needed to determine the effectiveness of different diagnostic modalities for pelvic anastomotic inspection.

The Usefulness of an Endoscopic OverStitch Suturing System for Managing Anastomotic Dehiscence - A Case Report

Anastomotic dehiscence (AD) after colorectal surgery contributes to poor outcomes resulting in multiple postoperative complications. Conventional management would be a repeat laparotomy and tension suturing. But owing to the unhealthy vicinities near the suture lines, there is a significant risk of technical failure which further increases postoperative morbidity and mortality. A 60-year-old male, with a history of hypertension, ischemic heart disease, and previous percutaneous transluminal coronary angioplasty, underwent sigmoid colectomy with colorectal anastomosis for complicated sigmoid diverticulitis. He then developed anastomotic site leak for which an ileostomy was done. Prior to the ileostomy revision, he was referred for colonoscopic evaluation which showed the persistence of a partial AD. We decided to close the defect endoscopically with the Apollo OverStitch device. Initial tissue preparation was done by creating a surgical surface using argon plasma coagulation at the perimeter of the leak site. A double channel therapeutic endoscope with the OverStitch assembly was passed to take full-thickness running sutures across the rent to facilitate full closure. The area examined showed good suture approximation and complete closure. The procedure was successful with no immediate or delayed postprocedural complications. Repeat endoscopic evaluation at about two weeks showed well-approximated edges with intact suture lines, and there was complete resolution of the leak. The patient subsequently underwent revision surgery after a month. The patient is under close follow-up and doing well. The Apollo OverStitch device has certainly opened new avenues in flexible endoscopic surgery which need further exploratory studies to add to existing promising results.

The possibility of a transanal tube as an alternative to diverting stoma in terms of preventing severe postoperative anastomotic leakage after laparoscopic low anterior resection

PURPOSE

The purpose of this study was to reveal whether a transanal tube (TAT) could act as an alternative to a diverting stoma (DS) after laparoscopic low anterior resection.

PATIENTS AND METHODS

A total of 89 consecutive rectal cancer patients whose tumors were located within 15 cm from the anal verge who underwent laparoscopic low anterior resection without a DS at our institution between May 12, 2015 and August 31, 2019 were included. All patients received a postoperative Gastrografin enema study (GES) through a TAT between the 3rd and 10th postoperative day. We planned two study protocols. From May 12, 2015 to March 31, 2017, we conducted a second operation including a DS construction immediately when radiological anastomotic leakage (rAL) was detected (Group A, n=46). From April 1, 2017 to August 31, 2019, we continued TAT drainage even if rAL was detected and repeated the GES weekly until the rAL was healed (Group B, n=43).

RESULTS

In Group A (n=46), 14 cases of rAL were included, 11 of which underwent stoma construction. The remaining 3 patients who refused stoma construction were treated conservatively. In Group B (n=43) rAL was encountered in 10, and 7 of these patients were treated successfully by TAT continuous drainage. The rate of DS in Group B (7.0%) was significantly lower than that in Group A (23.9%) (p=0.028).

CONCLUSIONS

A TAT could act as a DS to mitigate the symptoms of anastomotic leakage after laparoscopic low anterior resection.

The value of CT imaging and CRP quotient for detection of postbariatric complications

Background

The diagnosis of major complications seems to be more challenging in obese patients. We aimed to show the relevance of routinely assessed clinical and paraclinical parameters as well as the relevance of CT scans in the diagnosis of major complications after bariatric procedures.

Methods

All patients who underwent operations (primary or revisional) in a 3-year period were retrospectively studied after bariatric surgery with a specific focus on the routinely assessed clinical parameters (tachycardia, temperature), paraclinical parameters on postoperative day (POD) 1 and 3 (C-reactive protein (CRP), leukocytes), and additional computed tomography (CT) scan results for the diagnosis of leakage, bleeding, intraabdominal abscess, superficial abscess, and other complications.

Results

A total of 587 patients were examined. In this cohort, 73 CT scans were performed due to suspected intraabdominal or pulmonary complication according to our hospital standard operating procedure. In total, 14 patients (2.4%) had a major complication (Clavien-Dindo grade IV/V). Of those, 10 patients (1.7%) had postoperative leakage. While the correct leakage diagnosis was only found in 33% of the patients by CT scan, the overall specificity of CT as a diagnostic tool for all kinds of complications remained high. Especially for abscess detection, CT scan showed a sensitivity and specificity of 100%. Multivariate analysis showed a significantly higher risk of leakage development characterized by a doubling of postoperative CRP level (odds ratio 4.84 (95% confidence interval 2.01–11.66, p < 0.001)). To simplify the use of CRP as a predictive factor for the diagnosis of leakage, a cut-off value of 2.4 was determined for the CRP quotient (POD3/POD1) with a sensitivity of 0.88 and a specificity of 0.89.

Conclusion

CT diagnostic after bariatric surgery has a high positive predictive value, especially for intraabdominal abscess formation. Nevertheless, CT scan for the diagnosis of leakage has a low sensitivity. Thus, a negative CT scan does not exclude the presence of a leakage. Using the described CRP quotient with a cut-off of 2.4, the risk of early leakage can be easily estimated. Furthermore, in any uncertain case of clinically suspected leakage, diagnostic laparoscopy should be performed.

Radiographic Findings of Anastomotic Leaks

Although computed tomography (CT) scans play an important role in the diagnosis and management of anastomotic leaks (AL), there is no consensus on what radiographic findings are associated with AL. The purpose of this study is to identify the most common CT scan findings associated with AL and whether the amount of extraluminal air or the density of extraluminal fluid can be correlated with the presence of an AL. A retrospective chart review of 210 patients with anastomotic leaks from 2003 to 2010 at Mount Sinai Medical Center was performed. Eighty-six patients fit our criteria and were included. All CT scans were reread by an independent radiologist not involved with patient care. Our study included 59 per cent men and 41 per cent women with a mean age of 51 years. Diagnoses included inflammatory bowel disease (53%), malignancy (21%), and diverticulitis (12%). One hundred per cent of the patients had one of three findings: extraluminal air (92%), extraluminal fluid (88%), or extravasation of contrast (32%). Eighty-one per cent (70/86) had both fluid and air simultaneously. Extraluminal air was seen in 79 patients. The estimated amounts of extraluminal air were as follows: 0 to 25 mL (49%), 26 to 500 mL (41%), 500 to 1000 mL (5%), and more than 1000 mL (5%). The Hounsfield unit (HU) measurements of the fluid ranged from 3 to 633 HUs. The most common CT findings associated with AL are pneumoperitoneum and extraluminal fluid, including extravasation of contrast, which can be seen in up to 100 per cent of patients. The amount of estimated extraluminal air and density of fluid collection have no prognostic value in predicting AL.

Detection of early anastomotic leakage by intraperitoneal microdialysis after low anterior resection for rectal cancer: a prospective cohort study

AIM

Anastomotic leakage (AL) is a common and serious complication following sphincter-preserving surgery for rectal cancer. Early detection and intervention can improve clinical outcomes. The aim of this prospective cohort study was to compare intraperitoneal microdialysis with a clinical scoring system for early detection of AL.

METHOD

A microdialysis catheter was anchored near the anastomosis at low anterior resection (LAR) for rectal cancer. Peritoneal fluid samples were analysed (lactate, pyruvate, glucose and glycerol concentration) 4-hourly and compared with a daily clinical leak score (DULK = Dutch leakage). At day 7 a pelvic CT with rectal contrast enema was performed to establish if there had been a radiological leak.

RESULTS

In this two-centre study, 129 patients [median age 65 (26-82) years; 60.5% male] underwent LAR. The leak rate was 27% (grade A, n = 11; grade B, n = 12; grade C, n = 12). Receiver operator characteristic analysis demonstrated a lactate cut-off value of 9.8 mm and had 77% sensitivity, 82% specificity, 78% accuracy, a positive predictive value (PPV) of 58, a negative predictive value (NPV) of 88 (CI 79-94) and an area under the curve (AUC) of 0.9 for AL. This compared with a clinical score ≥ 4, which had 57% sensitivity, 79% specificity, 71% accuracy, a PPV of 46, a NPV of 82 and an AUC of 0.7 for AL. The mean day for a positive test when using delta lactate ≥ 6.3 mm was 1.6 days and for leak score ≥ 4 it was 3.3 days (NS).

CONCLUSION

When AL occurs, intraperitoneal lactate concentration increases over time, and at a certain cut-off has a higher sensitivity, specificity, accuracy, PPV and NPV than a clinical scoring system.

Management of anastomotic leakage after rectal surgery: a review article

Anastomotic leaks (ALs) are associated with increased perioperative morbidity and mortality, prolonged length of stay, higher readmission rates, the potential need for further operative interventions, and unintended permanent stomas; resulting in increased hospital costs and resource use, and decreased quality of life. This review article is to present definition, diagnosis and management strategies for AL after rectal surgery.

Is water-soluble contrast enema examination for integrity of rectal anastomosis necessary prior to ileostomy reversal?

Background and Aim

Routine use of water-soluble contrast enema (WSCE) to assess anastomotic integrity is debated. This study aimed to evaluate the role of WSCE to assess anastomotic integrity following anterior resections (AR) with defunctioning stoma prior to reversal and identify factors to limit its selective use.

Methods

This retrospective study evaluated all WSCE performed over a 7-year period at a high-volume colorectal unit. Risk factors for radiological abnormality/leak, including malignancy, chemoradiotherapy, and immediate postoperative complications, were recorded. A gastrointestinal specialist radiologist and surgeon validated all WSCEs reported as abnormal.

Results

Of the 486 WSCE studies identified, 92 were excluded (repeat studies (n = 51), pediatric cases [n = 2], no AR [n = 39]). A total of 394 WSCE studies were evaluated (260 cancer; 134 noncancer patients); 14% (37/260) of cancer patients and 8% (10/134) of noncancer patients had abnormal studies (P = 0.072). Of the 37 abnormal studies in cancer patients, 73% (27/37) radiological leaks were found, and 41% (n = 11/27) of these patients had postoperative complications. Of the 10 abnormal studies in noncancer patients, 20% (2/10) radiological leaks were found, but none of these patients had postoperative complications. Overall leak rates were 7% (29/394), and rates were significantly higher in cancer patients than noncancer patients (10 vs 2%, P = 0.005).

Conclusion

Routine use of WSCE may not be necessary prior to reversal. WSCE should be selectively used in event of postoperative leak or complications. Noncancer resections are less likely demonstrate a leak.

Recurrence of rectal anastomotic leakage following stoma closure: assessment of risk factors

AIM

In patients with a previous history of rectal anastomotic leakage (AL), the surgical indications and timing for closure of a diverting stoma have to be carefully judged. Even if AL has apparently healed before stoma closure, re-leakage may occur after closure. The aim of this study was to determine the incidence and risk factors for recurrent AL following stoma closure. We also examined the treatment strategies aiming to minimize the risk of recurrent AL.

METHODS

From January 2009 to December 2016, 1008 patients underwent sphincter-saving surgery [low anterior resection, all-sphincter-preserving rectal resection with hand-sewn coloanal anastomosis (CAA) and intersphincteric resection (ISR)] for primary rectal cancer with curative intent at our hospital. A total of 69 patients with AL with a Clavien-Dindo Grade III or more who subsequently underwent closure of a diverting stoma were retrospectively reviewed for this study.

RESULTS

The incidence of recurrent leakage after stoma closure in this series was 13% overall with an incidence of 25% in the CAA/ISR group and 5% in the low anterior resection group. Significant risk factors included hand-sewn anastomosis (P = 0.0257) compared to stapled anastomosis, ischaemia at the anastomotic site as the cause of initial AL (P < 0.001) and a shorter interval between confirmation of healing and stoma closure (P = 0.00952).

CONCLUSION

Ischaemia at the anastomotic site was the main risk factor for recurrent leakage, particularly after CAA/ISR. Additional treatment options before stoma closure should be considered to avoid re-leakage in such cases.

Prophylactic intra-abdominal drainage following colorectal anastomoses. A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Clinically evident Anastomotic Leakage (AL) remains one of the most feared complications after colorectal resections with primary anastomosis. The primary aim of this systematic review and meta-analysis was to determine whether Prophylactic Drainage (PD) after colorectal anastomoses confers any advantage in the prevention and management of AL.

METHODS

Systematic literature search was performed using MEDLINE, the Cochrane Central Register of Controlled Trials, and EMBASE databases for randomized studies comparing clinical outcomes of patients with Drained (D) or Undrained (UD) colorectal anastomoses performed for any cause.

RESULTS

Four randomized controlled trials comparing D and UD patients undergoing colorectal resections with primary anastomosis were included for quantitative synthesis. In total, 1120 patients were allocated to group D (n = 566) or group UD (n = 554). The clinical AL rate was 8.5% in the D group and 7.6% in the UD group, with no statistically significant difference (P = 0.57). Rates of radiological AL (D: 4.2% versus UD: 5.6%; P = 0.42), mortality (D: 3.6% versus UD: 4.4%; P = 0.63), overall morbidity (D: 16.6% versus UD: 18.6%, P = 0.38), wound infection (D: 5.4% versus UD: 5.3%, P = 0.95), pelvic sepsis (D: 9.7% versus UD: 10.5%, P = 0.75), postoperative bowel obstruction (D: 9.9% versus UD: 6.9%, P = 0.07), and reintervention for abdominal complication (D: 9.1% versus UD: 7.9%, P = 0.48) were equivalent between the two groups.

CONCLUSIONS

The present meta-analysis of randomized controlled trials investigating the value of PD following colorectal anastomoses does not support the routine use of prophylactic drains.

Diagnostic effectiveness of preoperative water-soluble contrast enema in colorectal perforation

OBJECTIVE

To evaluate the diagnostic usefulness of performing a preoperative water-soluble contrast enema (WSCE) before emergency surgery for colorectal perforation.

METHODS

We retrospectively reviewed 68 consecutive patients who underwent a preoperative WSCE before emergency surgery for colorectal perforation during the period from January 2011 to December 2017. Clinical characteristics and inflammatory biomarkers were compared between patients with Hinchey I-II versus those with Hinchey III-IV.

RESULTS

WSCE leakage occurred in 27 of 68 patients (39.7%). Univariate analysis showed that the two groups (Hinchey I-II and Hinchey III-IV) significantly differed regarding age, perforation site, cause of perforation, American Society of Anesthesiologists grade, presence or absence of WSCE leakage, and white blood cell count. Multivariable analysis revealed that WSCE leakage was a predictor of Hinchey III-IV, with an odds ratio of greater than 24 (P = 0.002). The sensitivity and specificity of WSCE leakage for differentiating those with Hinchey III-IV from those with Hinchey I-II were 76.5% and 97.1%, respectively.

CONCLUSIONS

This retrospective study indicates that preoperative WSCE before emergency surgery is a useful tool for predicting the presence of Hinchey III-IV in patients with colorectal perforation.

CT findings after pelvic exenteration: review of normal appearances and most common complications

The aim of this review is to illustrate normal computed tomography (CT) findings and the most common complications in patients who underwent pelvic exenteration (PE) for advanced, persistent or recurrent gynecological cancers. We review the various surgical techniques used in PE, discuss optimal CT protocols for postsurgical evaluation and describe cross-sectional imaging appearances of normal postoperative anatomic changes as well as early and late complications. The interpretation of abdominopelvic CT imaging after PE is very challenging due to remarkable modifications of normal anatomy. After this radical pelvic surgery, the familiarity with expected CT appearances is crucial for diagnosis and appropriate management of potentially life-threatening complications in patients who underwent PE.

Imaging of the Postoperative Colon

Recognition of postoperative complications is important for the immediate diagnosis and treatment needed for appropriate patient care. Identification of postoperative complications from colon surgery requires not only knowledge of the type of procedure, but also the expected normal postoperative appearance. The purpose of this article is to discuss and review the expected anatomic changes after colorectal surgery, and the appearance of the most common postoperative complications.

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.

The relationship between method of anastomosis and anastomotic failure after right hemicolectomy and ileo-caecal resection: an international snapshot audit

BACKGROUND

Anastomosis technique following right sided colonic resection is widely variable and may affect patient outcomes. This study aimed to assess the association between leak and anastomosis technique (stapled versus handsewn) METHODS: This was a prospective, multicentre, international audit including patients undergoing elective or emergency right hemicolectomy or ileo-caecal resection operations over a two-month period in early 2015. The primary outcome measure was the presence of anastomotic leak within 30 days of surgery, using a pre-specified definition. Mixed effects logistic regression models were used to assess the association between leak and anastomosis method, adjusting for patient, disease and operative cofactors, with centre included as a random effect variable.

RESULTS

This study included 3208 patients, of whom 78.4% (n=2515) underwent surgery for malignancy and 11.7% (n=375) for Crohn's disease. An anastomosis was performed in 94.8% (n=3041) of patients, which was handsewn in 38.9% (n=1183) and stapled in 61.1% (n=1858) cases. Patients undergoing handsewn anastomosis were more likely to be emergency admissions (20.5% handsewn versus 12.9% stapled) and to undergo open surgery (54.7% versus 36.6%). The overall anastomotic leak rate was 8.1% (245/3041), which was similar following handsewn (7.4%) and stapled (8.5%) techniques (p=0.3). After adjustment for cofactors, the odds of a leak were higher for stapled anastomosis (adjusted odds ratio 1.43, 95% confidence interval 1.04-1.95, p=0.03).

DISCUSSION

Despite being used in lower risk patients, stapled anastomosis was associated with an increased anastomotic leak rate in this observational study. Further research is needed to define patient groups in whom a stapled anastomosis is safe. This article is protected by copyright. All rights reserved.

The novel appearance of low rectal anastomosis on contrast enema following laparoscopic anterior resection: discriminating anastomotic leaks from "dog-ears" on water-soluble contrast enema and flexible sigmoidoscopy

PURPOSE

Interpretation of water-soluble contrast enema following laparoscopic low anterior resection can be very challenging for both radiologists and colorectal surgeons. Discriminating the radiological appearances secondary to anastomotic configuration from those caused by actual anastomotic dehiscence is a common problem and may be made worse with the advent of laparoscopic surgery. The aim of this study is to identify potential novel appearances of the water-soluble contrast enema (WSCE) images of rectal anastomosis following laparoscopic low anterior resection to radiologists and surgeons.

METHODS

We enrolled 45 patients who underwent laparoscopic low anterior resection with proximal de-functioning loop ileostomy within a specialized colorectal unit. The water-soluble contrast enema reports were reviewed. Two blinded colorectal radiologists independently reviewed the images of patients suspected of anastomotic leak. All of these patients also underwent a flexible sigmoidoscopy to confirm or exclude anastomotic leak before reversal of loop ileostomy. Inter-observer concordance was calculated.

RESULTS

Seven out of eighteen patients (38.9%) were found to have true anastomotic leaks on flexible sigmoidoscopy (15% overall leak rate). In the remaining eleven patients the image appearances were attributed to the appearance of the anastomotic 'dog-ear effect', created by the anastomotic configuration due to multiple firing of the intra-corporeal laparoscopic stapling device. Radiologist inter-observer concordance was 83%. Sensitivity was 100%, specificity 71%, positive-predictive value (38.9%) and negative-predictive value (100%).

CONCLUSIONS

The novel appearances of laparoscopic-stapled rectal anastomoses in WSCE can be mistaken for anastomotic leak. To avoid delay in reversal of ileostomy, a flexible sigmoidoscopy can be used to confirm or exclude a leak.

Post-operative colon and urinary diversions: surgical techniques, anatomy, and imaging findings

This article discusses the commonly encountered operative procedures of the colon and urinary diversions and provides a comprehensive review of indications, contraindications, surgical techniques with emphasis on normal and abnormal multimodality imaging findings.

Oncological impact of anastomotic leakage after laparoscopic mesorectal excision

BACKGROUND

The effect of anastomotic leakage on oncological outcomes after total mesorectal excision (TME) is controversial. This study aimed to assess the influence of symptomatic and asymptomatic anastomotic leakage on oncological outcomes after laparoscopic TME.

METHODS

All patients who underwent restorative laparoscopic TME for rectal adenocarcinoma with curative intent from 2005 to 2014 were identified from an institutional database. Asymptomatic anastomotic leakage was defined by CT performed systematically 4-8 weeks after rectal surgery, with no relevant clinical symptoms or laboratory examination findings during the postoperative course.

RESULTS

Of a total of 428 patients, anastomotic leakage was observed in 120 (28·0 per cent) (50 asymptomatic, 70 symptomatic). After a mean follow-up of 40 months, local recurrence was observed in 36 patients (8·4 per cent). Multivariable Cox regression identified three independent risk factors for reduced local recurrence-free survival (LRFS): symptomatic anastomotic leakage (odds ratio (OR) 2·13, 95 per cent c.i. 1·29 to 3·50; P = 0·003), positive resection margin (R1) (OR 2·41, 1·40 to 4·16; P = 0·001) and pT3-4 category (OR 1·77, 1·08 to 2·90; P = 0·022). Patients with no risk factor for reduced LRFS had an estimated 5-year LRFS rate of 87·7(s.d. 3·2) per cent, whereas the rate dropped to 75·3(4·3) per cent with one risk factor, 67(7) per cent with two risk factors, and 14(13) per cent with three risk factors (P < 0·001). Asymptomatic anastomotic leakage was not significantly associated with LRFS in multivariable analysis.

CONCLUSION

Symptomatic anastomotic leakage is a risk factor for disease recurrence in patients with rectal adenocarcinoma.

Integrated approach to colorectal anastomotic leakage: Communication, infection and healing disturbances

Colorectal anastomotic leakage (CAL) remains a major complication after colorectal surgery. Despite all efforts during the last decades, the incidence of CAL has not decreased. In this review, we summarize the available strategies regarding prevention, prediction and intervention of CAL and categorize them into three categories: communication, infection and healing disturbances. These three major factors actively interact during the onset of CAL. We aim to provide an integrated approach to CAL based on its etiology. The intraoperative air leak test, intraoperative endoscopy, radiological examinations and stoma construction mainly aim to detect and to prevent communication between the intra- and extra-luminal content. Other strategies including postoperative drainage, antibiotics, and infectious-parameter evaluation are intended to detect and prevent anastomotic or peritoneal infection. Most currently available interventions for CAL focus on the control of communication and infection, while strategies targeting the healing disturbances such as lifestyle changes, oxygen therapy and evaluation of metabolic biomarkers still lack wide clinical application. This simplified categorization may contribute to an integrated understanding of CAL. We strongly believe that this integrated approach should be taken into consideration during clinical practice. An integrated approach to CAL could contribute to a better understanding of the etiology of CAL and eventually better patient outcome.

Characteristics of 18F-fluorodeoxyglucose uptake in anastomotic sinus and fistula following rectal cancer surgery

PURPOSE

To assess the characteristics of 18F-fluorodeoxyglucose (FDG) uptake in persisting anastomotic sinus and fistula following rectal cancer surgery.

METHODS

Eight patients with anastomotic sinus and fistula were retrospectively studied.

RESULTS

A total of 13 anastomotic sinuses (n=11) and fistulas (n=2) were observed. Sixteen FDG-positron emission tomography/computed tomography studies for 13 lesions performed and 26 uptake patterns were evaluated. Twenty-one lesions were found to have diffuse increased uptake, whereas four lesions had focal uptake. There was only one lesion without FDG uptake.

CONCLUSIONS

Increased FDG uptake is frequently observed in anastomotic sinus and fistula, which should be known to avoid making wrong diagnosis.

Persistent Asymptomatic Anastomotic Leakage After Laparoscopic Sphincter-Saving Surgery for Rectal Cancer: Can Diverting Stoma Be Reversed Safely at 6 Months?

BACKGROUND

Anastomotic leakage after rectal cancer surgery raises the problem of the timing of diverting stoma reversal.

OBJECTIVE

The purpose of this study was to assess whether stoma reversal can be safely performed at 6 months after laparoscopic sphincter-saving surgery for rectal cancer with total mesorectal excision in patients with persistent asymptomatic anastomotic leakage.

DESIGN

This was a retrospective analysis of a prospective database.

SETTINGS

The study was conducted at a tertiary colorectal surgery referral center.

PATIENTS

All of the patients with anastomotic leakage were treated conservatively after sphincter-saving laparoscopic total mesorectal excision for rectal cancer.

MAIN OUTCOME MEASURES

The main study measure was postoperative morbidity.

RESULTS

A total of 110 (26%) of 429 patients who presented with anastomotic leakage and were treated conservatively were diagnosed only on CT scan (60 symptomatic (14%) and 50 asymptomatic (12%)). During follow up, 82 (75%) of 110 anastomotic leakages healed spontaneously after a mean delay of 16 ± 6 weeks (range, 4-30 weeks). Among these patients, 7 (9%) of 82 developed postoperative symptomatic pelvic sepsis after stoma reversal. Among the 28 patients remaining, 3 died during follow-up. The remaining 25 patients (23%) presented with persistent asymptomatic anastomotic leakage with chronic sinus >6 months after rectal surgery. Stoma reversal was performed in 19 asymptomatic patients, but 3 (16%) of 19 developed postoperative symptomatic pelvic sepsis after stoma reversal (3/19 vs 7/82 patients; p = 0.217), requiring a redo surgery with transanal colonic pull-through and delayed coloanal anastomosis (n = 2) or standard coloanal anastomosis (n = 1). Regarding the 6 final patients, abdominal redo surgery was performed because of either symptoms or anastomotic leakage with a large presacral cavity.

LIMITATIONS

This study was limited by its small sample size.

CONCLUSIONS

In the great majority of patients with persistent anastomotic leakage at 6 months after total mesorectal excision, stoma reversal can be safely performed.

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.

Assessment by Using a Water-Soluble Contrast Enema Study of Radiologic Leakage in Lower Rectal Cancer Patients With Sphincter-Saving Surgery

Purpose

This study evaluated the efficacy of a water-soluble contrast enema (WCE) in predicting anastomotic healing after a low anterior resection (LAR).

Methods

Between January 2000 and March 2012, 682 consecutive patients underwent a LAR or an ultra-low anterior resection (uLAR) and were followed up for leakage. Clinical leakage was established by using physical and laboratory findings. Radiologic leakage was identified by using retrograde WCE imaging. Abnormal radiologic features on WCE were categorized into four types based on morphology: namely, dendritic, horny, saccular, and serpentine.

Results

Of the 126 patients who received a concurrent diverting stoma, only two (1.6%) suffered clinical leakage due to pelvic abscess. However, 37 patients (6.7%) in the other group suffered clinical leakage following fecal diversion (P = 0.027). Among the 163 patients who received a fecal diversion, 20 showed radiologic leakage on the first WCE (eight with and 12 without a concurrent diversion); 16 had abnormal features continuously until the final WCE while four patients healed spontaneously. Eleven of the 16 patients (69%), by their surgeon's decision, underwent a stoma restoration based on clinical findings (2/3 dendritic, 3/4 horny, 5/7 saccular, 1/2 serpentine). After stoma reversal, only 2 of the 11 (19%) complained of complications related to the rectal anastomosis.

Conclusion

WCE is helpful for detecting radiologic leakage before stoma restoration, especially in patients suffering clinical leakage after an uLAR. However, surgeons appear to opt for stoma restoration despite the persistent existence of radiologic leakage in cases with particular features on the WCE.

Contrast medium at the site of the anastomosis is crucial in detecting anastomotic leakage with CT imaging after colorectal surgery

PURPOSE

The use of computed tomography (CT) to detect anastomotic leakage (AL) is becoming the standard of care. Accurate detection of AL is crucial. The aim of this study was to define CT criteria that are most predictive for AL.

METHODS

From January 2006 to December 2012, all consecutive patients who had undergone CT imaging because of clinical suspicion of anastomotic leakage after colorectal surgery were analysed. All CT scans were re-evaluated by two independent abdominal radiologists blinded for clinical outcome. The images were scored with a set of criteria and a conclusion whether or not AL was present was drawn. Each separate criterion was analysed for its value in predicting AL by uni- and multivariable logistic regression

RESULTS

Of 668 patients with colorectal surgery, 108 had undergone CT imaging within 16 days postoperatively. According to our standard of reference, 34 (31%) of the patients had AL. Univariable analysis showed that "fluid near anastomosis" (radiologist 1 (rad 1), p < 0.001; radiologist 2 (rad 2), p < 0.001) and "air near anastomosis" (rad 1, p < 0.001; rad 2, p < 0.001), "air intra-abdominally" (rad 1, p = 0.019; rad 2, p = 0.004) and "contrast leakage" (rad 1, p < 0.001; rad 2, p < 0.001) were associated with AL. Contrast leakage was the only independent predictor for AL in multivariable analysis for both radiologists (rad 1, OR 5.43 (95% CI 1.18-25.02); rad 2, OR 8.51 (95% CI 2.21-32.83)).

CONCLUSION

The only independent variable predicting AL is leakage of contrast medium. To improve the accuracy of CT imaging, optimal contrast administration near the anastomosis appears to be crucial.

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.

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.

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.

CT scan-based modelling of anastomotic leak risk after colorectal surgery

AIM

Prolonged ileus, low-grade fever and abdominal discomfort are common during the first week after colonic resection. Undiagnosed anastomotic leak carries a poor outcome and computed tomography (CT) scan is the best imaging tool for assessing postoperative abdominal complications. We used a CT scan-based model to quantify the risk of anastomotic leak after colorectal surgery.

METHOD

A case-control analysis of 74 patients who underwent clinico-radiological evaluation after colorectal surgery for suspicion of anastomotic leak was undertaken and a multivariable analysis of risk factors for leak was performed. A logistic regression model was used to identify determinant variables and construct a predictive score.

RESULTS

Out of 74 patients with a clinical suspicion of anastomotic leak, 17 (23%) had this complication confirmed following repeat laparotomy. In multivariate analysis, three variables were associated with anastomotic leak: (1) white blood cells count > 9 × 10(9) /l (OR = 14.8); (2) presence of ≥ 500 cm(3) of intra- abdominal fluid (OR = 13.4); and (3) pneumoperitoneum at the site of anastomosis (OR = 9.9). Each of these three parameters contributed one point to the risk score. The observed risk of leak was 0, 6, 31 and 100%, respectively, for patients with scores of 0, 1, 2 and 3. The area under the receiver operating characteristic curve for the score was 0.83 (0.72-0.94).

CONCLUSION

This CT scan-based model seems clinically promising for objective quantification of the risk of a leak after colorectal surgery.

Beware of false-negative CT scan for anastomotic leakage after colonic surgery

BACKGROUND

Anastomotic leakage is one of the most life-threatening complications after colonic surgery. Correct diagnosis and treatment is important to reduce morbidity and mortality. An abdominal CT scan is one of the main diagnostic tools in diagnosing anastomotic leaks. The aim of this study was to examine the accuracy of abdominal CT scanning to detect anastomotic leakage and to evaluate the consequences of a false-negative CT outcome.

METHODS

All consecutive patients who underwent colonic resection for malignant disease between 2009 and 2011 or for benign disease in 2010 were reviewed. Patients in whom a postoperative abdominal CT scan was performed to detect anastomotic leakage were included.

RESULTS

In 97 of 524 patients who underwent colonic surgery, an abdominal CT scan was performed for the suspicion of anastomotic leakage. Overall leakage rate was 10.9 % (n = 57). Mortality rate after leakage was 21.1 % (n = 12). Results from all abdominal CT scans revealed an overall sensitivity of 0.59 (95 % CI 0.43-0.73), a specificity of 0.88 (95 % CI 0.75-0.95), positive predictive value 0.82 (95 % CI 0.64-0.92), negative predictive value 0.70 (95 % CI 0.57-0.81), and an accuracy of 74 %. Delayed reintervention for anastomotic leakage due to a false-negative CT outcome resulted in death in 62.5 % (n = 5).

CONCLUSION

The sensitivity of abdominal CT scanning after colonic surgery is relatively low. A negative CT scan does not rule out anastomotic leakage. Even with a negative CT scan, we should remain equally alert at clinical deterioration as an argument for timely intervention.