Prediction of perioperative complications in colorectal cancer via artificial intelligence analysis of heart rate variability

Figure 2 Fluctuation of time-domain and frequency-domain heart rate variability analysis parameters during the perioperative period in the perioperative complication group and non-perioperative complication group. A: The SDNN data throughout the day; B: The data of pNN50; C: The data of RMSSD; D: The data of LF; E: The data of HF; F: The data of LF/HF. ^aP < 0.05, ^cP < 0.001, the NPC group vs PC group; ^gP < 0.05, ^hP < 0.01, ^lP < 0.001, vs Pre in the non-perioperative complication group; ^dP < 0.05, ^eP < 0.01, vs Pre in the perioperative complication group. SDNN: Standard deviation of N-N intervals; RMSSD: Mean of the squared differences between adjacent normal RR intervals; LF: Low-frequency band; HF: High-frequency band; NPC: Non-perioperative complication; PC: Perioperative complication; Pre: Preoperative day; Pod: Post-operative day.