title: The prolongation of pulse transit time after a stellate ganglion block: An objective indicator of successful block.
abstract: BACKGROUND
  An objective marker of successful stellate ganglion block (SGB) does not exist. Horner syndrome, which is currently used to determine the effect of SGB, is sometimes ambiguous.
  
  
  OBJECTIVE
  To investigate the change in pulse transit time (PTT) after SGB, and to evaluate the utility of PTT as an objective measure of successful SGB.
  
  
  METHODS
  Eight patients (34 to 62 years of age) underwent SGB for diagnosis or treatment of sympathetically mediated pain of the upper extremities. The success of the SGB was determined according to the presence of Horner syndrome. Electrocardiography, noninvasive blood pressure measurements and pulse oximetry were used to monitor all patients. PTT was measured using data saved on the WinDaq waveform browser.
  
  
  RESULTS
  PTT was measured at baseline and 3 min, 5 min and 10 min after the injection of a local anesthetic. At 3 min after SGB, the mean (± SD) PTT was 624.6±20.5 ms. At 5 min after injection, the mean PTT was 630.8±17.5 ms. Prolonged PTT at 5 min was found to return to the baseline value at 10 min (613.6±14.7 ms). According to the Friedman test, the differences from baseline values were significant (P=0.008).
  
  
  CONCLUSIONS
  Measurement of PTT at 5 min after local anesthetic injection can help to objectively determine the success of SGB.
authors.forename: Young Uk
authors.initials: YU
authors.lastname: Kim
authors.forename: Yuseon
authors.initials: Y
authors.lastname: Cheong
authors.forename: Yu Gyeong
authors.initials: YG
authors.lastname: Kong
authors.forename: Jonghyuk
authors.initials: J
authors.lastname: Lee
authors.forename: Sehun
authors.initials: S
authors.lastname: Kim
authors.forename: Hong Gyu
authors.initials: HG
authors.lastname: Choi
authors.forename: Jeong Hun
authors.initials: JH
authors.lastname: Suh
mesh_terms: D000328:Adult; D001340:Autonomic Nerve Block / Q000379:methods*; D001794:Blood Pressure / Q000502:physiology; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000601:surgery*; D011446:Prospective Studies; D063177:Pulse Wave Analysis; D013233:Stellate Ganglion / Q000502:physiology*; D013997:Time Factors