Systematic review of the definition and measurement of anastomotic leak after gastrointestinal surgery

Background: Anastomotic leak after gastrointestinal surgery is an important postoperative event that leads to significant morbidity and mortality. Postoperative leak rates are frequently used as an indicator of the quality of surgical care provided. Comparison of rates between and within institutions depends on the use of standard definitions and methods of measurement of anastomotic leak. The aim of this study was to review the definition and measurement of anastomotic leak after oesophagogastric, hepatopancreaticobiliary and lower gastrointestinal surgery. Methods: A systematic review was undertaken of the published literature. Searches were carried out on five bibliographical databases (Medline, Embase, The Cochrane Library, Cumulative Index for Nursing and Allied Health Literature and HealthSTAR) for English language articles published between 1993 and 1999. Articles were critically appraised by two independent reviewers and data on definition and measurement of anastomotic leak were extracted. Results: Ninety-seven studies were reviewed and a total of 56 separate definitions of anastomotic leak were identified at three sites: upper gastrointestinal (13 definitions), hepatopancreaticobiliary (14) and lower gastrointestinal (29). The majority of studies used a combination of clinical features and radiological investigations to define and detect anastomotic leak. Conclusion: There is no universally accepted definition of anastomotic leak at any site. The definitions and values used to measure anastomotic failure vary extensively and preclude accurate comparison of rates between studies and institutions.