Effects of anaesthesia and surgery on sleep–wake timing and subjective sleep quality in children: an observational study

Introduction: Surgery and anaesthesia can cause disruption of the circadian timing system and diurnal sleep–wake rhythm. However, it remains unknown how sleep–wake rhythm in children is affected by anaesthesia and surgery, and if anaesthesia without a surgical procedure disturbs sleep–wake cycles. Methods: We recruited children aged 1–11 y undergoing anaesthesia for an elective surgical procedure or magnetic resonance imaging. The Children's Chronotype Questionnaire, Children's Sleep Habits Questionnaire and a daily sleep diary from three days before until seven days after anaesthesia were used to assess sleep–wake rhythm and sleep quality. Results: In total, 117 patients (median (IQR [range]) age 4 (2–6 [1–11]) y, 56 (47.9%) female) were included. The midpoint of sleep did not change on the night after anaesthesia when compared with three nights before (estimated median time difference 8 min, 95%CI -15–1, p = 0.12, n = 114). Median (IQR [range]) midpoint of sleep at baseline was 01.42 (01.22–02.19 [00.10–03.15]) for the surgical group and 01.22 (01.03–02.07 [00.15–04.02]) for the magnetic resonance imaging group. The midpoint of sleep did not shift on the night after anaesthesia for either group (surgical group: 01.37 (01.07–02.15 [23.00–03.12]), estimated median time difference -15 min, 95%CI -27–0, p = 0.07, n = 58; magnetic resonance imaging group: 01.30 (01.07–02.07 [23.45–05.00]), estimated median time difference 0 min, 95%CI -9–9, p = 0.90, n = 56), and there was no between-group difference (estimated median time difference: -15 min, 95%CI -30–0 min, p = 0.07). Subjective sleep quality was unaffected. Discussion: We found no disruption of sleep–wake rhythm in children after anaesthesia and surgery. Further research is needed to see whether more invasive procedures and accompanying anaesthesia pose a risk of disrupting sleep–wake rhythms in children.