Performance of an Automated Algorithm Grading Surgery-Related Adverse Events According to the Clavien-Dindo Classification: A Systematic Review

Postoperative adverse events (AEs) significantly impact patient outcomes and healthcare resources. The Clavien-Dindo Classification (CDC) is widely used to grade surgical complications, but manual grading is labor-intensive and subject to inter-observer variability. Automated algorithms, including rule-based, machine learning (ML), and large language model (LLM)-based natural language processing (NLP) tools, offer scalable solutions for consistent complication grading. A systematic review was conducted following PRISMA 2020 guidelines. Databases searched included PubMed, Embase, Scopus, and Cochrane Library. Studies reporting automated grading of surgery-related AEs using the CDC as a reference, with human validation, were included. Data extraction covered algorithm type, sample size, surgical population, comparator, data source, performance metrics, and outcomes. Three studies met the inclusion criteria, encompassing a total of 1,661 surgical cases. Automated algorithms for Clavien-Dindo Classification (CDC) grading including rule-based systems, machine-learning (ML) models, and large language model (LLM)/natural language processing (NLP) approaches demonstrate high agreement with expert reviewers, with rule-based algorithms achieving Cohen's κ up to 0.89, ML prediction models reporting discrimination up to an AUC of 0.863 for severe (CDC ≥ III) complications, and LLM/NLP approaches reaching accuracy of approximately 97% and Cohen's κ up to 0.92. Together, these methods show potential for scalable and, in some settings, near-real-time postoperative complication monitoring. These tools may support clinical decision-making, research, and quality improvement with promising but preliminary applicability across surgical domains. However, conclusions are limited by the small number of available studies and heterogeneity in surgical settings.