Analysis of perioperative autonomic nervous system activity to visualize stress in pediatric patients undergoing alveolar bone graft surgery

Abstract

Perioperative stress in pediatric patients is often difficult to assess via interviews; thus, an objective measure to assess perioperative stress is needed. To visualize perioperative stress, we observed autonomic nervous system (ANS) activity, circulatory dynamics, and psychological status in pediatric patients undergoing alveolar bone grafting under general anesthesia. This prospective observational study included 40 patients aged 8-12 years who were scheduled for alveolar bone grafting in our hospital. ANS activity was analyzed using heart rate variability the day before surgery, during general anesthesia, 2 h postoperatively, 24 h postoperatively, and the day before discharge. ANS assessment included LF/HF (sympathetic nervous system activity) and HF (parasympathetic nervous system activity). Additionally, heart rate (HR), systolic blood pressure (SBP), face scale (FS) score were recorded. Data from 31 patients, excluding dropouts, were analyzed. The ratio of change to the preoperative value was compared. After surgery, the LF/HF, HR, SBP, and FS score significantly increased (P < 0.01) and HF significantly decreased (2 h postoperatively: P < 0.05, 24 h postoperatively, before discharge: P < 0.01). SBP recovered to preoperative values 24 h postoperatively, and HR and FS scores recovered to preoperative values before discharge. However, even before discharge, LF/HF remained significantly higher than preoperative values, and HF remained significantly lower than preoperative values (P < 0.01). Conclusion We observed perioperative stress from multiple perspectives. Circulatory dynamics and psychological status recovered by the day before discharge; however, ANS activity did not. Therefore, evaluating ANS activity may be useful in visualizing potential perioperative stress in pediatric patients.

Keywords: Alveolar bone grafting; Autonomic nervous system activity; General anesthesia; Pediatric patients; Perioperative stress.

Fig. 1

Time course of assessments. Data were measured preoperatively, during general anesthesia, 2 h postoperatively, 24 h postoperatively, and before discharge. Abbreviations: HRV, heart rate variability; LF, low frequency; HF, high frequency; SBP, systolic blood pressure; HR, heart rate; PONV, postoperative nausea and vomiting

Fig. 2

Comparison of (a) LF/HF, (b) HF, (c) HR, (d) SBP, and (e) face scale score at each time point between the groups. The face scale before anesthesia was assessed after entering the operating room. LF/HF, HF, HR, SBP, and face scale scores are expressed as relative ratios to preoperative values. Abbreviations: LF/HF, low-to-high frequency ratio; HF, high frequency; HR, heart rate; SBP, systolic blood pressure. All data are presented as mean and standard error. The level of statistical significance was set at P values < 0.05. * P < 0.05. ** P < 0.01