Definition and grading of anastomotic leakage following right hemicolectomy

Dear Editor Anastomotic leakage (AL) is a major complication after right hemicolectomy (RHC), with associated negative impact on short- and long-term outcomes1–3. To date, no uniformity in the definition and grading of AL has been achieved, which hinders further investigation4. To address existing variation, two Delphi rounds were conducted on the definition, diagnosis and grading of AL following RHC. This was performed as a preliminary study for the COLOR IV trial (NCT05493033), an international multicentre trial comparing intracorporeal and extracorporeal anastomosis after laparoscopic RHC. An adapted Delphi methodology coupled with core group discussions was employed. A webinar was held in February 2022, led by a consortium of expert surgeons—two from the Netherlands and five from China. The webinar aimed to address three pivotal aspects about AL following RHC: definition, diagnosis, and grading. The expert team ultimately formulated 30 statements across these domains. The Delphi process was executed via online questionnaires across two rounds. A consensus threshold was set at an agreement level above 80%. Statements with less than 20% agreement eliminated. The initial Delphi round commenced on 3 August 2022, concluding on 16 August 2022, with participation from 201 colorectal surgeons across 32 Chinese provinces. This round resulted in 13 statements with an agreement rate exceeding 80%, whereas 5 had less than 20% consensus. Following an online discussion by the core group, the second questionnaire incorporated the remaining 12 statements and introduced an additional statement. The second Delphi round, involving 129 surgeons, took place between 6 February and 19 February 2023. Ultimately, consensus was reached on 14 statements. Following two Delphi rounds, consensus was achieved on 14 of 31 statements, with a 100% response rate for all statements. Consensus broadly concurred that AL following RHC is characterized by a defect of the intestinal wall at the anastomotic site leading to communication between the intra- and extraluminal compartments5. Clinical manifestations including fever (>37.5°C), abdominal pain not related to the incision, sepsis and peritonitis may signal the onset of clinically suspected AL. Pertinent laboratory indicators include elevated white blood cell counts (>12 × 109/l), procalcitonin (>0.5 μg/l) and C-reactive protein (>50 mg/l) 3 days after surgery. The definitive confirmation of AL is established through the observation of faecal drainage fluid, extravasation of contrast agent into the peritoneal cavity on CT scan, air bubbles surrounding the anastomosis on CT or anastomotic dehiscence observed during secondary laparoscopy or laparotomy. Regarding grading, both the International Study Group of Rectal Cancer classification and the Clavien–Dindo classification are deemed suitable frameworks. Detailed results are delineated in Table 1. Results of the Delphi with the statements and percentage of agreement per round Statements with agreement rates below 20% are excluded, those above 80% are retained, and those between 20% and 80% proceeded to the second round of surveys. The underlined statement was newly added in the second round of questionnaires. CT, computed tomography. Results of the Delphi with the statements and percentage of agreement per round Statements with agreement rates below 20% are excluded, those above 80% are retained, and those between 20% and 80% proceeded to the second round of surveys. The underlined statement was newly added in the second round of questionnaires. CT, computed tomography. This study was undertaken to circumvent standardize the definition and grading of AL after RHC. It should be noted that the agreed definitions distinguish between clinically suspected AL, which requires further radiologic evaluation to confirm its presence, and confirmed AL. The definition and judgement criteria have been successfully applied upfront in a previously published multicentre snapshot study4 and underpin quality control across participating institutions in the COLOR IV study. This work was supported by grants from the National Key R&D Program of China (2017YFC0110904); Special Fund for Clinical Medicine Development, Beijing Municipal Hospital Administration (No. ZYLX201504); Program of Clinical Center for Colorectal Cancer of Capital Medical University (1192070313); Beijing Hospitals Authority Clinical Medicine Development of special funding support (ZLRK202302). Bo Feng, Department of General Surgery, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China. Ziqiang Wang, Department of General Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China. Yi Xiao, Division of Colorectal Surgery, Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College Beijing, China. The three professors mentioned above, together with Hendrik Bonjer, Jurriaan Tuynman, Hongwei Yao and Zhongtao Zhang, form the core group of experts for this Delphi study. No potential conflict of interest was reported by the authors. Data used and analysed during this study are available from the corresponding author on reasonable request.