Clinical value of AI-based heart rate variability combined with the E-PASS scoring system in gastrointestinal function recovery after abdominal surgery

[Objectives] To investigate factors influencing gastrointestinal function recovery after abdominal surgery using AI-based heart rate variability (HRV) monitoring combined with the estimation of physiologic ability and surgical stress (EPASS) scoring system. [Methods] Clinical data from 148 patients undergoing laparoscopic abdominal surgery in the Department of General Surgery, Affiliated Hospital of Nanjing University of Chinese Medicine, between December 2021 and May 2024 were collected. Patients were categorized into low-scoring and high-scoring groups based on the E-PASS system. HRV parameters (the average normal-to-normal intervals [SDNN], standard deviation of the average NN intervals [SDANN], triangular index, percentage of difference between adjacent normal RR intervals exceeding 50 milliseconds [PNN50], normalized low-frequency [LFnu], normalized high-frequency [HFnu] and low-frequency/high-frequency power ratio [LF/HF]) were observed preoperatively and on postoperative days (POD) 1 and 3. Postoperative first flatus time, hospital stay, complications, and inflammatory markers were compared between groups. Factors influencing gastrointestinal dysfunction were analyzed. [Results] Preoperative HRV indices showed no significant differences between groups (P>0.05). On POD 1, the triangular index differed significantly(P<0.017), while other HRV indices did not (P>0.017). On POD 3, significant differences were observed in SDNN, SDANN, triangular index, PNN50, LFnu, and HFnu (P<0.017). There were no significant difference in LF/HF (P>0.017). Multivariate Logistic regression revealed that E-PASS score, operative time, intraoperative blood loss, and preoperative HFnu were independent influencing factors for postoperative gastrointestinal dysfunction. [Conclusion] The E-PASS score influences gastrointestinal function recovery after abdominal surgery. Patients with an E-PASS score <-0.3 demonstrated faster recovery.