Systematic review on the value of CT scanning in the diagnosis of anastomotic leakage after colorectal surgery

Parenteral n-3 polyunsaturated fatty acids supplementation improves postoperative recovery for patients with Crohn's disease after bowel resection: a randomized, unblinded controlled clinical trial

BACKGROUND

The postoperative inflammatory response is associated with postoperative recovery in surgery. n-3 (ω-3) polyunsaturated fatty acids have been reported to lower inflammation. The postoperative role of parenteral n-3 polyunsaturated fatty acids supplementation on outcomes in Crohn's disease after bowel resection is unclear.

OBJECTIVES

We aimed to investigate the effects of postoperative parenteral n-3 polyunsaturated fatty acids supplementation in Crohn's disease.

METHODS

A prospective randomized, unblinded controlled clinical trial was conducted for patients with Crohn's disease who underwent bowel resection between May 2019 and February 2022. Postoperative complications, complete blood count, serum biochemical values, and cytokine concentrations were compared in patients with and without parenteral n-3 polyunsaturated fatty acids supplementation for 5 d postoperatively.

RESULTS

There were 268 patients randomly assigned in the analysis, with 134 in the control group (a mix of long-chain and medium-chain fats at 1.0 g/kg/d) and 134 in the treatment group (long-chain, medium-chain, and n-3 polyunsaturated fats at 1.2 g/kg/d). Twenty-six did not complete the allocated treatment, and 8 patients were lost to follow-up. The intention-to-treat analysis and the per-protocol analysis showed that there were a significant reduction in overall complication rates (22.4% compared with 49.3%; P < 0.001 and 21.8% compared with 38.2%; P = 0.006) and postoperative stay (8.8 ± 4.5 d compared with 11.2 ± 6.8 d; P = 0.001 and 8.7 ± 4.0 d compared with 11.5 ± 7.3 d; P < 0.001) in patients with parenteral n-3 polyunsaturated fatty acids supplementation compared with patients in the control group. In the secondary outcomes, the mean ± standard deviation of interleukin (IL)-6 (17.11 ± 2.14 pg/mL compared with 30.50 ± 5.14 pg/mL; P = 0.014), IL-1β (2.01 ± 0.05 pg/mL compared with 2.24 ± 0.09 pg/mL; P = 0.019), tumor necrosis factor-α (2.09 ± 0.06 pg/mL compared with 2.29 ± 0.06 pg/mL; P = 0.029), and C-reactive protein concentrations (51.3 ± 4.2 mg/L compared with 64.4 ± 5.3 mg/L; P = 0.050) on postoperative day 5 in the treatment group were much lower than those in the control group.

CONCLUSIONS

Parenteral n-3 polyunsaturated fatty acids supplementation promotes postoperative recovery in patients with Crohn's disease following bowel resection, with fewer complications and reduced inflammatory cytokines. This trial was registered at clinicaltrials.gov as NCT03901937 at https://classic.

CLINICALTRIALS

gov/ct2/show/NCT03901937?term=NCT03901937&cond=Crohn+Disease&draw=2&rank=1.

Endoscopic management of anastomotic leakage after colorectal cancer surgery in a Moroccan center: A case series and literature review

Endoscopic management has become an alternate treatment to a revision surgery for colorectal fistulas. Eight patients who were treated by endoscopy for postoperative anastomotic leakage to colorectal cancer were included. A univariate analysis was carried out to determine the predictive factors of success. All our patients were treated using metallic clips. The primary efficiency of this technique was 50%. In a univariate analysis, the size of the fistula and its distance from the anal margin had an influence on the efficiency of the endoscopic treatment, which was not the case for either the surgical technique or the use of neoadjuvant radiotherapy. This endoscopic treatment is effective and represents a more secure alternative than revision surgery. In our study, the use of metallic clips showed a 50% success rate, going up to 100% for the group of patients with a fistula ostium of a size ⩽1 cm, proving the necessity of using this technique.

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.

Early postoperative endoscopic evaluation of rectal anastomoses: a prospective cross-sectional study

BACKGROUND

Reported incidence of anastomotic leakage (AL) of rectal anastomoses is up to 29% with an overall mortality up to 12%. Nevertheless, there is no uniform evidence-based diagnostic procedure for early detection of AL. The objective of this prospective clinical trial was to demonstrate the diagnostic value of early postoperative flexible endoscopy for rectal anastomosis evaluation.

METHODS

Flexible endoscopy between 5 and 8th postoperative day was performed consecutively in 90 asymptomatic patients. Sample size calculation was made using the two-stage Simon design. Diagnostic value was measured by management change after endoscopic evaluation. Anastomoses were categorized according to a new classification. Study is registered in German Clinical Trials Register (DRKS00019217).

RESULTS

Of the 90 anastomoses, 59 (65.6%) were unsuspicious. 20 (22.2%) were suspicious with partial fibrin plaques (n = 15), intramural hematoma and/or local blood coagulum (n = 4) and ischemic area in one. 17 of these anastomoses were treated conservatively under monitoring. In three a further endoscopic re-evaluation was performed and as consequence one patient underwent endoscopic vacuum therapy. 11 (12.2%) AL were detected. Here, two could be treated conservatively under monitoring, four with endoscopic vacuum therapy and five needed revision surgery. No intervention-related adverse events occurred. A change in postoperative management was made in 31 (34.4%) patients what caused a significant improvement of diagnosis of AL (p < 0.001).

CONCLUSIONS

Early postoperative endoscopic evaluation of rectal anastomoses is a safe procedure thus allows early detection of AL. Early treatment for suspicious anastomoses or AL could be adapted to avoid severe morbidity and mortality.

Development of a warning score for early detection of colorectal anastomotic leakage: Hype or hope?

BACKGROUND

Colorectal anastomotic leakage (CAL), a severe postoperative complication, is associated with high morbidity, hospital readmission, and overall healthcare costs. Early detection of CAL remains a challenge in clinical practice. However, some decision models have been developed to increase the diagnostic accuracy of this event.

AIM

To develop a score based on easily accessible variables to detect CAL early.

METHODS

Based on the least absolute shrinkage and selection operator method, a predictive classification system was developed [Early ColoRectAL Leakage (E-CRALL) score] from a prospective observational, single center cohort, carried out in a colorectal division from a non-academic hospital. The score performance and CAL threshold from postoperative day (POD) 3 to POD5 were estimated. Based on a precise analytical decision model, the standard clinical practice was compared with the E-CRALL adoption on POD3, POD4, or POD5. A cost-minimization analysis was conducted, on the assumption that all alternatives delivered similar health-related effects.

RESULTS

In this study, 396 patients who underwent colorectal resection surgery with anastomosis, and 6.3% (n = 25) developed CAL. Most of the patients who developed CAL (n = 23; 92%) were diagnosed during the first hospital admission, with a median time of diagnosis of 9.0 ± 6.8 d. From POD3 to POD5, the area under the receiver operating characteristic curve of the E-CRALL score was 0.82, 0.84, and 0.95, respectively. On POD5, if a threshold of 8.29 was chosen, 87.4% of anastomotic failures were identified with E-CRALL adoption. Additionally, score usage could anticipate CAL diagnosis in an average of 5.2 d and 4.1 d, if used on POD3 and POD5, respectively. Regardless of score adoption, episode comprehensive costs were markedly greater (up to four times) in patients who developed CAL in comparison with patients who did not develop CAL. Nonetheless, the use of the E-CRALL warning score was associated with cost savings of €421442.20, with most (92.9%) of the savings from patients who did not develop CAL.

CONCLUSION

The E-CRALL score is an accessible tool to predict CAL at an early timepoint. Additionally, E-CRALL can reduce overall healthcare costs, mainly in the reduction of hospital costs, independent of whether a patient developed CAL.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Treatment Modalities for Anastomotic Leakage in Rectal Cancer Surgery

Despite advances in rectal cancer surgery, anastomotic leakage (AL) remains a common complication with a significant impact on patient recovery, health care costs, and oncologic outcomes. The spectrum of clinical severity associated with AL is broad, and treatment options are diverse with highly variable practices across the colorectal community. To be effective, the treatment must match not only the patient's current status but also the type of leak, the surgeon's skill, and the resources available. In this chapter, we will review the current and emergent treatment modalities for AL after rectal cancer surgery.

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

AIM

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

METHOD

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

RESULTS

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

CONCLUSION

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Postoperative complications of colorectal cancer

Colorectal cancer is the third most common cancer, and surgery is the most common treatment. Several surgical options are available, but each is associated with a range of potential complications. The timely and efficient identification of these complications is vital for effective clinical management of these patients in order to minimise their morbidity and mortality. This review aims to describe the range of commonly performed surgical treatments for colorectal surgery. In addition, frequent post-surgical complications are explored with investigative options explained and illustrated.

How to reduce failure to rescue after visceral surgery?

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

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

OBJECTIVE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

Consensus on the definition of colorectal anastomotic leakage: A modified Delphi study

BACKGROUND

Despite the emerging knowledge about colorectal anastomotic leakage (CAL) through the increasing number of clinical and experimental studies, there is no generally accepted definition of CAL. Because of the wide variety of definitions used in literature, comparison of study outcomes and quality of care is complicated.

AIM

To reach consensus on the definition of CAL using a modified Delphi method.

METHODS

The RAND/UCLA appropriateness method was used. The expert panel consisted of international colorectal surgeons and researchers who had published three or more articles about CAL. The consensus process consisted of two online distributed questionnaires and a third round with a recommendation. In the questionnaires participants were asked to rate the appropriateness of statements using a 1-9 Likert scale. Consensus was defined as a panel median between 1-3 or 7-9 without disagreement. In the final round a recommendation was formed regarding the definition of CAL and the expert panel was asked if they agreed or disagreed.

RESULTS

Twenty-three authors participated in the first round and twenty-one finished the second round. After two rounds consensus was reached on 37 items (80%) in nine different categories. The International Study Group of Rectal Cancer definition is the most frequently advised general definition by our panel. Consensus was reached regarding the clinical symptoms of CAL, which serum markers contributes to the suspicion of CAL, which radiological and perioperative findings should be considered as CAL, which grading system is appropriate and if there should be a range of postoperative days in the definition. Eventually, 19 experts completed all three rounds of which 16 (84%) agreed with our final recommendations for the definition of CAL.

CONCLUSION

A consensus-based recommendation for the definition of CAL was formed using our modified Delphi method that can be widely incorporated in the field.

Serum C-reactive protein is a useful marker to exclude anastomotic leakage after colorectal surgery

Anastomotic leakage is a complication of colorectal surgery. C-reactive protein (CRP) is an acute-phase marker that can indicate surgical complications. We determined whether serum CRP levels in patients who had undergone colorectal surgery can be used to exclude the presence of anastomotic leakage and allow safe early discharge. We included 90 patients who underwent colorectal surgery with primary anastomosis. Serum CRP levels were measured retrospectively on postoperative days (PODs) 1 - 7. Patients with anastomotic leakage (n = 11) were compared to those without leakage (n = 79). We statistically analysed data and plotted receiver operating characteristic curves. The incidence of anastomotic leakage was 12.2%. Diagnoses were made on PODs 3 - 24. The overall mortality rate was 3.3% (18.2% in the leakage group, 1.3% in the non-leakage group; P < 0.045). CRP levels were most accurate on POD 4, with a cutoff level of 180 mg/L, showing an area under the curve of 0.821 and a negative predictive value of 97.2%. Lower CRP levels after POD 2 and levels <180 mg/L on POD 4 may indicate the absence of anastomotic leakage and may allow safe discharge of patients who had undergone colorectal surgery with primary anastomosis.

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.

Urgent Multidetector Computed Tomography in Colon Cancer: Postsurgical Changes and Early Complications

Complications after surgery for colorectal cancer are common in emergency departments. Multidetector computed tomography plays a fundamental role in the follow-up of patients after surgery, because it enables the detection of relapse and complications. Radiologists need to be familiar with different surgical techniques and the normal postsurgical changes so that we can differentiate them from potential complications and relapse. This article reviews the multidetector computed tomography findings that can be considered normal after surgical intervention for colorectal cancer as well as the most common early complications seen in postsurgical colorectal cancer patients presenting at emergency departments.

Transanal Tube Drainage as a Conservative Treatment for Anastomotic Leakage Following a Rectal Resection

Purpose

We evaluate the role of transanal tube drainage (TD) as a conservative treatment for patients with anastomotic leakage (AL).

Methods

Patients treated for AL who had undergone a low or an ultralow anterior resection with colorectal or coloanal anastomosis for the treatment of rectal cancer between January 2013 and January 2017 were enrolled in this study. The data were collected prospectively and analyzed retrospectively. The primary outcomes were the diagnosis and the management of AL.

Results

Two hundred thirteen consecutive patients, 122 males and 91 females, were included. The mean age was 66.91 ± 11.15 years, and the median body mass index was 24 kg/m² (range, 20–35 kg/m²). The median tumor distance from the anal verge was 8 cm (range, 4–12 cm). Ninety-three patients (44%) received neoadjuvant therapy for nodal disease and/or locally advanced rectal cancer. Only 13 patients (6%) developed AL. Six patients developed subclinical AL as they had a defunctioning ileostomy at the time of the initial procedure. They were treated conservatively with TD under endoscopic guidance in the endoscopy unit and received intravenous antibiotics. Six weeks after discharge, these 6 patients underwent follow-up flexible sigmoidoscopy which showed a completely healed anastomotic defect with no residual stenosis. Seven patients developed a clinically significant AL and required reoperation with pelvic abscess drainage and Hartmann colostomy formation.

Conclusion

These results suggest that TD for management of patients with AL is safe, cheap, and effective. Salvaging the anastomosis will help decrease the need for Hartmann colostomy formation. Proper patient selection is important.

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.

Postoperative Interleukin-6 Level and Early Detection of Complications After Elective Major Abdominal Surgery

OBJECTIVE

To assess the association of systemic inflammation and outcome after major abdominal surgery.

BACKGROUND

Major abdominal surgery carries a high postoperative morbidity and mortality rate. Studies suggest that inflammation is associated with unfavorable outcome.

METHODS

Levels of C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-α and the systemic inflammatory response syndrome (SIRS) were assessed in 137 patients undergoing major abdominal surgery. Blood samples were drawn on days 0, 1, 3, and 7, and SIRS was scored during 48 hours after surgery. Primary outcome was a composite of mortality, pneumonia, sepsis, anastomotic dehiscence, wound infection, noncardiac respiratory failure, atrial fibrillation, congestive heart failure, myocardial infarction, and reoperation within 30 days of surgery.

RESULTS

An IL-6 level more than 432 pg/mL on day 1 was associated with an increased risk of complications (adjusted odds ratio: 3.3; 95% confidence interval [CI]: 1.3-8.5) and a longer median length of hospital stay (7 vs 12 days, P < 0.001). As a single test, an IL-6 cut-off level of 432 pg/mL on day 1 yielded a specificity of 70% and a sensitivity of 64% for the prediction of complications (area under the curve: 0.67; 95% CI: 0.56-0.77). Levels of CRP started to discriminate from day 3 onward with a specificity of 87% and a sensitivity of 58% for a cut-off level of 203 mg/L (AUC: 0.73; 95% CI: 0.63-0.83).

CONCLUSIONS

A high IL-6 level on day 1 is associated with postoperative complications. Levels of IL-6 help distinguish between patients at low and high risk for complications before changes in levels of CRP.

[Characteristics of postoperative peritonitis]

Postoperative peritonitis is still a life-threatening complication after abdominal surgery and approximately 10,000 patients annually develop postoperative peritonitis in Germany. Early recognition and diagnosis before the onset of sepsis has remained a clinical challenge as no single specific screening test is available. The aim of therapy is a rapid and effective control of the source of infection and antimicrobial therapy. After diagnosis of diffuse postoperative peritonitis surgical revision is usually inevitable after intestinal interventions. Peritonitis after liver, biliary or pancreatic surgery is managed as a rule by means of differentiated therapy approaches depending on the severity.

Evaluation of peripheral blood and abdominal fluid variables as predictors of intestinal surgical site failure in dogs with septic peritonitis following celiotomy and the placement of closed-suction abdominal drains

OBJECTIVE To evaluate peripheral blood and abdominal fluid variables as predictors of intestinal surgical site failure in dogs with septic peritonitis following celiotomy and closed-suction abdominal drain (CSAD) placement. DESIGN Prospective study. ANIMALS 26 dogs with septic peritonitis that underwent celiotomy and CSAD placement. PROCEDURES Abdominal fluid and blood samples were collected prior to surgery and daily thereafter until CSAD removal. Abdominal fluid was collected through the CSAD. Analysis of all samples included pH, PCO2, PO2, PCV, WBC count, and total solids, glucose, lactate, and electrolyte concentrations. Abdominal fluid samples also underwent cytologic evaluation and bacterial culture, and the volume of fluid removed through the drain was recorded daily. The blood-to-fluid glucose and lactate differences, fluid-to-blood lactate ratio and blood-to-fluid WBC and neutrophil ratios were determined daily. Dogs were categorized into 2 groups on the basis of whether they had an uneventful recovery (UR) or developed postoperative septic peritonitis (POSP). RESULTS 23 dogs had a UR and 3 developed POSP. On the third day after surgery, the abdominal fluid WBC count was significantly lower and the blood-to-fluid WBC and neutrophil ratios were significantly higher for dogs in the POSP group, compared with those for dogs in the UR group. None of the other blood and abdominal fluid variables assessed differed significantly between the 2 groups. CONCLUSIONS AND CLINICAL RELEVANCE Results failed to identify any objective predictive indicators for POSP in dogs with CSADs. Use of blood-to-fluid WBC and neutrophil ratios as predictive indicators for POSP requires further investigation.

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.

Early complication detection after colorectal surgery (CONDOR): study protocol for a prospective clinical diagnostic study

PURPOSE

Anastomotic leakage is one of the most feared complications following colorectal surgery with a high morbidity and mortality rate. Multiple risk factors have been identified, but leakage still occurs. Early detection is crucial in order to reduce morbidity and mortality. The aim of this study is to create a decision algorithm for early detection of anastomotic leakage.

METHODS

All patients who undergo elective colorectal surgery for benign or malignant disease are enrolled in this multicenter study. The primary endpoint is the accuracy of the prediction of anastomotic leakage. The main study parameter is the occurrence of postoperative anastomotic leakage. Secondary study parameters are clinical (vital) parameters, additional laboratory or radiology examination, other complications, mortality, re-intervention, duration of hospital and intensive care stay, emergency room visits, readmission to the hospital and total costs. Daily physical examination and each step in clinical decision making will be evaluated prospectively in a standardized manner. The focus of the analysis will be on the added value of diagnostic tools, such as laboratory results and imaging studies, over physical examination by using logistic regression and decision tree analysis.

CONCLUSION

This study aims to develop an optimal diagnostic algorithm that can act as a guideline for surgeons or surgical residents to early identify patients with anastomotic leakage after colorectal surgery.

Longterm -ostomy as a quality marker: Comparison of outcomes from a six year series of laparoscopic surgery in MRI defined low rectal cancer

AIM

We propose long-term -ostomy rate following laparoscopic rectal cancer resection must be included as an overall quality indicator of treatment in conjunction with frequently reported and readily available end points.

METHOD

A database was collated prospectively of consecutive rectal cancer resections over a 6-year period. Recorded data included pre-operative MRI (tumour stage and height from the anal-verge), as well as demographics, treatment, local recurrence rate, survival and -ostomy rate as the primary outcome measure.

RESULTS

65 patients were identified and classified as low-rectal cancer if the tumour on MRI was < 6 cm from the anal verge or middle/upper-rectal cancer if between 6 and 15 cm from the anal-verge and below the peritoneal reflection. Permanent stoma rates including colostomies and non-reversed ileostomies were 31.7% for middle/upper rectal cancer; 62.5% for low-rectal cancer and an overall rate of 42.1% for all rectal cancers. For upper-rectal cancer the rates of local recurrence, predicted mortality, R0 resection and conversion were: 0%, 1.9%, 97.6% and 0% respectively. Corresponding figures for low-rectal cancer were: 4.2%, 2.7%, 95.8% and 0%. There were no significant differences for age, sex, predicted morbidity/mortality, survival, recurrence or leak rates between the groups.

CONCLUSION

Laparoscopic rectal cancer surgery has a comparable permanent -ostomy rate to open rectal cancer surgery. We benchmark 31.7% as the permanent -ostomy rate for upper-rectal cancer and 62.5% for low-rectal cancer following laparoscopic resection, in the context of 96.9% R0 resection and 0% conversion rate in a consecutive series of patients.

The marker C-reactive protein is helpful in monitoring the integrity of anastomosis: plasma calprotectin

BACKGROUND

Despite improved surgical techniques and materials, anastomotic leakage is a big problem for surgeons. The most frequently used laboratory parameters is leukocyte (white blood cell) and C-reactive protein (CRP). Availability of plasma calprotectin with CRP to detect anastomotic leakage was studied.

METHODS

In this prospective study of 41 (male/female 18/23) patients in the anastomosis group, 30 (male/female 20/10) patients were included in the control group. The anastomosis groups viewed in preoperatively day and postoperatively 1st, 3rd, and 5th day of CRP, white blood cell, and plasma calprotectin values.

RESULTS

Anastomosis group with complications and without complications were studied. Statistically significant similarities between plasma calprotectin and CRP levels in the postoperative period were observed.

CONCLUSION

Plasma calprotectin in monitoring the integrity of the anastomosis can be used with a marker CRP.

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.

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.

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.

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.

Accurate prediction of anastomotic leakage after colorectal surgery using plasma markers for intestinal damage and inflammation

BACKGROUND

Anastomotic leakage is a frequent and life-threatening complication after colorectal surgery. Early recognition of anastomotic leakage is critical to reduce mortality. Because early clinical and radiologic signs of anastomotic leakage are often nonspecific, there is an urgent need for accurate biomarkers. Markers of inflammation and gut damage might be suitable, as these are hallmarks of anastomotic leakage.

STUDY DESIGN

In 84 patients undergoing scheduled colorectal surgery with primary anastomosis, plasma samples were collected preoperatively and daily after surgery. Inflammatory markers, C-reactive protein; calprotectin; and interleukin-6, and intestinal damage markers, intestinal fatty acid binding protein; liver fatty acid binding protein; and ileal bile acid binding protein, were measured. Diagnostic accuracy of single markers or combinations of markers was analyzed by receiver operating characteristic curve analysis.

RESULTS

Anastomotic leakage developed in 8 patients, clinically diagnosed at median day 6. Calprotectin had best diagnostic accuracy to detect anastomotic leakage postoperatively. Highest diagnostic accuracy was obtained when C-reactive protein and calprotectin were combined at postoperative day 3, yielding sensitivity of 100%, specificity of 89%, positive likelihood ratio = 9.09 (95% CI, 4.34-16), and negative likelihood ratio = 0.00 (95% CI, 0.00-0.89) (p < 0.001). Interestingly, preoperative intestinal fatty acid binding protein levels predicted anastomotic leakage at a cutoff level of 882 pg/mL with sensitivity of 50%, specificity of 100%, positive likelihood ratio = infinite (95% CI, 4.01-infinite), and negative likelihood ratio = 0.50 (95% CI, 0.26-0.98) (p < 0.0001).

CONCLUSIONS

Preoperative intestinal fatty acid binding protein measurement can be used for anastomotic leakage risk assessment. In addition, the combination of C-reactive protein and calprotectin has high diagnostic accuracy. Implementation of these markers in daily practice deserves additional investigation.

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.

Prophylactic anastomotic drainage for colorectal surgery

BACKGROUND

There is little agreement on prophylactic use of drains in anastomoses in elective colorectal surgery despite many randomized clinical trials. Results of these trials are contradictory, quality and statistical power of these individual studies have been questioned. Once anastomotic leakage has occurred it is generally agreed that drains should be used for therapeutic purposes. However, on prophylactic use no such agreement exists.

OBJECTIVES

Comparison of safety and effectiveness of routine drainage and non-drainage regimes after colorectal surgery. The following hypothesis was tested: The use of prophylactic anastomotic drainage after elective colorectal surgery does not prevent development of complications.

SEARCH STRATEGY

The studies were identified from CINAHL, EMBASE, LILACS, MEDLINE, Controlled Clinical Trials Database, Trials Register of the Cochrane Colorectal Cancer Group, reference lists.

SELECTION CRITERIA

Randomized controlled trials comparing drainage with non-drainage regimes after anastomoses in elective colorectal surgery were reviewed. Outcome measures were: 1. mortality; 2. clinical anastomotic dehiscence; 3. radiological anastomotic dehiscence; 4. wound infection; 5. reoperation; 6. extra-abdominal complications.

DATA COLLECTION AND ANALYSIS

Data were independently extracted and cross-checked by the two reviewers. The methodological quality of each trial was assessed. Details of the randomization (generation and concealment), blinding, and the number of patients lost to follow-up were recorded. The RCTs were stratified based on experimental group, according to clinical homogeneity (external validity).

MAIN RESULTS

Of the 1140 patients enrolled (6 RCTs), 573 were allocated for drainage and 567 for no drainage. The patients assigned to the drainage group compared with the ones assigned to non-drainage group showed: a) Mortality: 3% (18 of 573 patients) compared with 4% (25 of 567 patients); b) Clinical anastomotic dehiscence: 2% (11 of 522 patients) compared with 1% (7 of 519 patients); c) Radiological anastomotic dehiscence: 3% (16 of 522 patients) compared with 4% (19 of 519 patients); d) Wound infection: 5% (29 of 573 patients) compared with 5% (28 of 567 patients); e) Reintervention: 6% (34 of 542 patients) compared with 5% (28 of 539 patients); f) Extra abdominal complications: 7% (34 of 522 patients) compared with 6% (32 of 519 patients).

REVIEWERS' CONCLUSIONS

There is insufficient evidence showing that routine drainage after colorectal anastomoses prevents anastomotic and other complications.