title: Heart rate variability during total intravenous anesthesia: effects of nociception and analgesia.
abstract: BACKGROUND
  Changes in heart rate variability (HRV) during anesthesia likely result from the interaction of hypnosis, surgical stimulation, analgesia and direct cardiovascular effects of drugs, but the interaction between these variables is unclear. This study was designed to characterize the impact of both surgical nociception and analgesia on HRV in propofol-anesthetized patients.
  
  
  METHODS
  HRV was analyzed using wavelet transform in 49 patients (ASA status 1-2) before induction of anesthesia and then throughout stable anesthesia with propofol, in the absence of nociceptive stimulation, and then during surgery, in the presence of deep (adequate) or light (inadequate) analgesia provided by various opioids (sufentanil [n=19], alfentanil [n=18], or remifentanil [n=12].
  
  
  RESULTS
  Anesthesia reduced total power as well as high frequency (HF) and low frequency (LF) powers (all: P<0.01), with an increase (P=0.002) in the proportional part of HF power (HFnu). During nociception, HFnu decreased in a sensitive and reproducible way (P<0.01) in case of light analgesia, whereas HRV did not change when patient received adequate analgesia.
  
  
  CONCLUSIONS
  The nociception-analgesia balance is a direct determinant of HRV during surgical anesthesia. HFnu may behave like an early indicator of inadequate analgesia. These results have potential implication for monitoring adequacy of analgesia in healthy patients undergoing intravenous anesthesia. Additional work is needed for application across patient populations.
authors.affiliation: Pôle d'Anesthésie Réanimation, hôpital Roger Salengro, CHU de Lille, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Jeanne
authors.forename: Régis
authors.initials: R
authors.lastname: Logier
authors.forename: Julien
authors.initials: J
authors.lastname: De Jonckheere
authors.forename: Benoît
authors.initials: B
authors.lastname: Tavernier
mesh_terms: D000328:Adult; D000344:Afferent Pathways / Q000187:drug effects / Q000503:physiopathology; D000777:Anesthetics / Q000009:adverse effects*; D018686:Anesthetics, Intravenous / Q000009:adverse effects; D001145:Arrhythmias, Cardiac / Q000139:chemically induced* / Q000503:physiopathology*; D003243:Consciousness / Q000187:drug effects / Q000502:physiology; D005260:Female; D006321:Heart / Q000187:drug effects / Q000294:innervation / Q000503:physiopathology; D006339:Heart Rate / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D006991:Hypnosis, Anesthetic / Q000009:adverse effects; D007431:Intraoperative Complications / Q000209:etiology / Q000503:physiopathology; D008297:Male; D009619:Nociceptors / Q000187:drug effects / Q000502:physiology; D010146:Pain / Q000150:complications* / Q000503:physiopathology; D015742:Propofol / Q000009:adverse effects; D013564:Sympathetic Nervous System / Q000187:drug effects / Q000503:physiopathology; D055815:Young Adult
chemical_list: D000777:Anesthetics; D018686:Anesthetics, Intravenous; D015742:Propofol