title: Comparing the effect of arginine vasopressin on ear and finger photoplethysmography.
abstract: OBJECTIVE
  To test whether the relative insensitivity of craniofacial vessels to catecholamines differs in response to arginine vasopressin.
  
  
  METHODS
  Prospective, observational human study.
  
  
  METHODS
  University hospital.
  
  
  METHODS
  8 ASA physical status I and II women scheduled for elective myomectomy.
  
  
  METHODS
  Patients underwent elective myomectomy surgery with intrauterine injection of arginine vasopressin.
  
  
  METHODS
  Finger, ear, and forehead photoplethysmographs were monitored. Changes in the plethysmographic amplitudes were recorded before and after arginine vasopressin injection.
  
  
  RESULTS
  In all subjects, ear photoplethysmographic amplitude (but not oxygen saturation) decreased precipitously (62% +/- 10%; P < 0.001) after arginine vasopressin injection. In contrast, there was no significant decline in the finger signal (4.5% +/- 27%; P = 0.19). The forehead plethysmograph decreased in amplitude, but this finding did not achieve significance (33% +/- 18%; P = 0.18).
  
  
  CONCLUSIONS
  In contrast to prior observations during adrenergic activation, arginine vasopressin induced relatively greater vasoconstriction at the ear and forehead than at the finger. This finding has potential implications with respect to arginine vasopressin's effect on blood flow and indicates that monitoring the ear plethysmographic signal may provide useful information during arginine vasopressin administration.
authors.affiliation: Department of Anesthesiology, Yale University, New Haven, CT 06520, USA.
authors.forename: Denis H
authors.initials: DH
authors.lastname: Jablonka
authors.forename: Aymen A
authors.initials: AA
authors.lastname: Awad
authors.forename: Robert G
authors.initials: RG
authors.lastname: Stout
authors.forename: David G
authors.initials: DG
authors.lastname: Silverman
authors.forename: Kirk H
authors.initials: KH
authors.lastname: Shelley
mesh_terms: D002395:Catecholamines / Q000502:physiology; D004423:Ear / Q000098:blood supply*; D005260:Female; D005385:Fingers / Q000098:blood supply*; D005546:Forehead / Q000098:blood supply; D006801:Humans; D007889:Leiomyoma / Q000098:blood supply / Q000601:surgery*; D017156:Photoplethysmography / Q000187:drug effects* / Q000379:methods; D011446:Prospective Studies; D014661:Vasoconstriction / Q000502:physiology; D014662:Vasoconstrictor Agents / Q000494:pharmacology*; D014667:Vasopressins / Q000494:pharmacology*
chemical_list: D002395:Catecholamines; D014662:Vasoconstrictor Agents; D014667:Vasopressins