title: Sympathetic skin response evoked by respiratory stimulation as a measure of sympathetic function.
abstract: OBJECTIVE
  To compare respiratory and electrical methods of evoking a sympathetic skin response (SSR).
  
  
  METHODS
  SSRs evoked by both electrical and respiratory stimulation were recorded from the palms of 47 healthy volunteers. Expiration and inspiration were used as separate stimuli. The correlation coefficients between the amplitude and latency of the SSR from the palm electrodes and the various components of heart rate variability were calculated.
  
  
  RESULTS
  Waveform patterns of the SSRs obtained from electrical stimulation showed varied responses to and habituation to this type of stimulation. On the other hand, no subjects showed a phase change in SSR waveform patterns between the first and last expiratory stimuli. The potentials recorded after expiratory stimulation had significantly greater amplitudes than those recorded after electrical stimuli. The low frequency component of heart rate variability induced by expiratory stimulation was significantly greater than that induced by electrical stimulation. The SSR may also correlate strongly with the change of respiratory rate since a more rapid pressure change occurs during expiratory movement than during inspiratory movements.
  
  
  CONCLUSIONS
  The SSR evoked by expiratory stimulation is more reliable than either electrical stimulation or inspiratory stimulation for determining sympathetic function.
authors.affiliation: Department of Orthopaedic Surgery, Kyoto Prefectural Rehabilitation Hospital for the Mentally and Physically Disabled, Naka Ashihara, Johyo City, 610-0113, Kyoto, Japan. kiray@mb.neweb.ne.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Kira
authors.forename: T
authors.initials: T
authors.lastname: Ogura
authors.forename: S
authors.initials: S
authors.lastname: Aramaki
authors.forename: T
authors.initials: T
authors.lastname: Kubo
authors.forename: T
authors.initials: T
authors.lastname: Hayasida
authors.forename: Y
authors.initials: Y
authors.lastname: Hirasawa
mesh_terms: D000328:Adult; D004558:Electric Stimulation; D004562:Electrocardiography; D004576:Electromyography; D005260:Female; D006185:Habituation, Psychophysiologic; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D001239:Inhalation / Q000502:physiology; D008297:Male; D012016:Reference Values; D015656:Respiratory Mechanics / Q000502:physiology*; D012867:Skin / Q000294:innervation*; D013564:Sympathetic Nervous System / Q000502:physiology*