Continuous Wrist‐Derived Heart Rate Correlates With m YPAS Scores and Detects Between‐Assessment Heart‐Rate Elevations in Children: A Feasibility Study

BACKGROUND: Perioperative anxiety affects most children undergoing surgery and predicts emergence delirium, postoperative pain, and behavioral change. The validated modified Yale Preoperative Anxiety Scale (mYPAS) is scored at only a few discrete timepoints, leaving physiologic status between assessments unmeasured. AIMS: We tested whether continuous wearable heart rate correlates with the mYPAS where scored, and whether heart-rate elevations of undetermined cause occur during intervals without concurrent mYPAS observation. METHODS: Children aged 4-17 undergoing elective surgery wore a wrist biosensor (Empatica EmbracePlus) from holding through induction; the mYPAS was scored at consent, parental separation, and induction. We assessed heart rate-mYPAS concordance and the proportion of heart-rate elevations falling outside ±5 min of any mYPAS timepoint, stratified by premedication. RESULTS: Of 32 consented children, 15 were analyzable (median age 10 years, nine male, eight premedicated). Induction-window heart rate correlated with induction anxiety (Spearman ρ = 0.55, 95% CI 0.01-0.84, p = 0.034) and rose into induction in 13 of 15 children (median + 10 beats/min, p = 0.022). Of 90 heart-rate elevations among 14 children with reliable timing, 71% fell outside the assessment windows (95% CI 58%-80%); 12 of 14 (86%) had ≥ 1 event outside all assessment windows. This pattern persisted regardless of premedication. Heart rate tracked children's state self-report (ρ = 0.62, ages ≥ 9) but not trait anxiety; informants agreed modestly. CONCLUSIONS: In this small feasibility cohort, wrist-derived induction-window heart rate was associated with concurrent mYPAS scores. The majority of heart-rate elevations of undetermined cause occurred outside scheduled mYPAS assessment windows. These exploratory findings require confirmation in a larger study incorporating raw physiologic signals, motion measurement, and continuous or event-linked behavioral assessment, which would establish whether continuous physiologic monitoring can complement intermittent behavioral assessment by identifying physiologic events occurring between scheduled anxiety assessments.