title: Increased non-stationarity of heart rate during general anaesthesia with sevoflurane or desflurane in children.
abstract: BACKGROUND
  During general anaesthesia, the most prominent change in heart rate variability (HRV) is a decrease in the magnitude of heart rate (HR) oscillation in the high- and low-frequency ranges. In children receiving sevoflurane or desflurane, we observed a significant increase in HR non-stationarity, that is, a significant change of mean HR over time. The aim of our study was to describe this increased non-stationarity and compare it with the decrease in the magnitude of HR oscillation.
  
  
  METHODS
  Sixty children received sevoflurane (n=30) or desflurane anaesthesia (n=30). The magnitude of HR oscillation and non-stationarity during pre-anaesthesia and anaesthesia were measured by spectral and Hurst analyses using structure function, respectively.
  
  
  RESULTS
  Low- and high-frequency powers decreased significantly and the very-short-term (2<or=tau<or=8 s, H(alpha)) and short-term Hurst exponent (8<or=tau<or=45 s, H(beta)) increased significantly during the anaesthetic period compared with the pre-anaesthetic period, regardless of the anaesthetic agent [sevoflurane: mean (sd) H(alpha) 0.414 (0.169) vs 0.252 (0.0655), H(beta) 0.481 (0.169) vs 0.078 (0.0409); desflurane H(alpha) 0.336 (0.171) vs 0.261 (0.0614), H(beta) 0.471 (0.221) vs 0.0813 (0.049)]. Stepwise discriminant analysis showed that the short-term Hurst exponent was better than the spectral indices at differentiating between the pre-anaesthetic period and anaesthetic period.
  
  
  CONCLUSIONS
  During sevoflurane and desflurane anaesthesia in children, there is a significant increase in very-short-term and short-term HR non-stationarity. Furthermore, the greater short-term non-stationarity differentiates better between the pre-anaesthesia and anaesthesia than the decreased magnitude of HR oscillation in the high- and low-frequency ranges.
authors.affiliation: Department of Pediatrics, Hanyang University College of Medicine, Seoul, South Korea.
authors.forename: M-K
authors.initials: MK
authors.lastname: Yum
authors.forename: J-T
authors.initials: JT
authors.lastname: Kim
authors.forename: H-S
authors.initials: HS
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D001683:Biological Clocks / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D000077335:Desflurane; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D007223:Infant; D007432:Intraoperative Period; D007530:Isoflurane / Q000031:analogs & derivatives* / Q000494:pharmacology; D008297:Male; D008738:Methyl Ethers / Q000494:pharmacology*; D016343:Monitoring, Intraoperative / Q000379:methods; D000077149:Sevoflurane; D012815:Signal Processing, Computer-Assisted
chemical_list: D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D000077149:Sevoflurane; D000077335:Desflurane; D007530:Isoflurane