title: Inappropriate sympathetic activation at onset of septic shock: a spectral analysis approach.
abstract: The autonomic cardiovascular control was investigated in 10 patients with septic shock, 10 patients with sepsis syndrome, and six tilted healthy subjects. Overall variability, high- and low-frequency components (AUC, HF, and LF, beats/min(2)/Hz or mm Hg(2)/Hz) from heart rate (HR), systolic (SBP) and diastolic (DBP) blood pressures spectra were obtained from 5-min recordings. LF(HR)/HF(HR) and the square root of LF(SBP)/LF(HR) (alpha) were used as indices of sympathovagal interaction and baroreflex control of the heart, respectively. Compared with tilted control subjects and patients with sepsis syndrome, septic shock is characterized by reduction in: (1) HR variability, i.e., decreased AUC(HR) (p = 0.007), LF(HR) (p = 0.002), and LF(HR)/HF(HR) (p = 0.0002); (2) DBP variability, i.e., decreased AUC(DBP) (p = 0.003) and LF(DBP) (p = 0.001), (3) alpha (p = 0.003). In septic shock, LF(HR)/HF(HR), alpha, and LF(DBP) correlated with mean blood pressure (r = 0.67, p = 0.04, r = 0.64, p = 0.03, and r = 0.88, p = 0.0008, respectively), and with plasma norepinephrine levels (r = -0.65, p = 0.03, r = -0.79, p = 0.006, and r = -0.69, p = 0.03, respectively). In conclusion, onset of septic shock is characterized by high concentrations of circulating catecholamines but impaired sympathetic modulation on heart and vessels, suggesting that central autonomic regulatory impairment contributes to circulatory failure.
authors.affiliation: Service de Réanimation Médicale, Hôpital Raymond Poincaré, Faculté de Médecine Paris Ouest, Université Paris V, Paris, France.
authors.forename: D
authors.initials: D
authors.lastname: Annane
authors.forename: F
authors.initials: F
authors.lastname: Trabold
authors.forename: T
authors.initials: T
authors.lastname: Sharshar
authors.forename: I
authors.initials: I
authors.lastname: Jarrin
authors.forename: A S
authors.initials: AS
authors.lastname: Blanc
authors.forename: J C
authors.initials: JC
authors.lastname: Raphael
authors.forename: P
authors.initials: P
authors.lastname: Gajdos
mesh_terms: D000328:Adult; D001143:Arousal / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D015924:Blood Pressure Monitors; D002319:Cardiovascular System / Q000294:innervation; D005260:Female; D005583:Fourier Analysis; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood; D011311:Pressoreceptors / Q000503:physiopathology; D012016:Reference Values; D012772:Shock, Septic / Q000503:physiopathology*; D012815:Signal Processing, Computer-Assisted; D013564:Sympathetic Nervous System / Q000503:physiopathology*; D018746:Systemic Inflammatory Response Syndrome / Q000503:physiopathology*; D018667:Tilt-Table Test; D014630:Vagus Nerve / Q000503:physiopathology
chemical_list: D009638:Norepinephrine