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

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.

Usefulness of CT scan as part of an institutional protocol for proactive leakage management after low anterior resection for rectal cancer

PURPOSE

Highly selective fecal diversion after low anterior resection (LAR) for rectal cancer requires a strict postoperative protocol for early detection of anastomotic leakage (AL). The purpose of this study was to evaluate C-reactive protein (CRP)-based CT imaging in diagnosis and subsequent management of AL.

METHODS

All patients that underwent a CT scan for suspicion of AL after transanal total mesorectal excision for rectal cancer in a university center (2015-2020) were included. Outcome parameters were diagnostic yield of CT and timing of CT and subsequent intervention.

RESULTS

Forty-four out of 125 patients underwent CT (35%) with an overall median interval of 5 h (IQR 3-6) from CRP measurement. The anastomosis was diverted in 7/44 (16%). CT was conclusive or highly suspicious for AL in 23, with confirmed AL in all those patients (yield 52%), and was false-negative in one patient (sensitivity 96%). CT initiated subsequent intervention after median 6 h (IQR 3-25). There was no or minor suspicion of AL on imaging in all 20 patients without definitive diagnosis of AL. After CT imaging on day 2, AL was confirmed in 0/1, and these proportions were 6/6 for day 3, 7/10 for day 4, 2/4 for day 5, and 9/23 beyond day 5.

CONCLUSION

In the setting of an institutional policy of highly selective fecal diversion and pro-active leakage management, the yield of selective CT imaging using predefined CRP cut-off values was 52% with a sensitivity of 96%, enabling timely and tailored intervention after a median of 6 h from imaging.

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.

"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.

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.

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.

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.

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.

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.