Classification of Intraoperative Complications

It is with great interest that we read the manuscript titled: ‘‘Definition and Classification of Intraoperative Complications (CLASSIC): Delphi Study and Pilot Evaluation,’’ published online ahead of print in the World Journal of Surgery on February 10, 2015 [1]. In the introduction to their study, Rosenthal et al. state that they are ‘‘not aware of any validated reporting system addressing intraoperative complications.’’ We would like to courteously point out to the authors the publication in the Journal of the American College of Surgeons of a very similar classification of intraoperative adverse events (iAEs) by Kaafarani et al. on February 28, 2014 (printed in that same year’s June issue) [2]. Our novel classification was derived using a similar modified Delphi process, and its intra-class correlation coefficient was measured at 0.88. Rosenthal et al. acknowledged the clear need to validate their suggested classification. In comparison, we have already validated our classification by testing the correlation between the severity of iAEs and 30-day postoperative outcomes, and demonstrated that iAEs with severity class C3 were correlated with worse 30-day morbidity and mortality. In addition, we have since described the nature, patterns, predictors, and clinical/financial outcomes of iAEs in several published or in press manuscripts, and presented our results in national and international meetings [3–7]. In summary, we would like to emphasize three points: First, a novel classification of intraoperative adverse events has been published by our group at the Massachusetts General Hospital and Harvard Medical School. Second, this classification has been validated and is currently being validated further on an even greater scale. Third, we are currently conducting and planning additional research in this area and would welcome the collaboration of interested groups, like Rosenthal et al.’s, in order to create a sum outcome that is bigger than its parts.