title: Ultrasonic investigation of the effect of topical glyceryl trinitrate on peripheral arm vein diameter: implications for intravenous nutrition.
abstract: BACKGROUND
  It has been suggested that topical glyceryl trinitrate (GTN) ointment may cause venodilatation and hence deter thrombophlebitis. However, objective evidence of an increase in vein diameter has not been demonstrated.
  
  
  METHODS
  B mode ultrasonography was used to measure arm vein diameter. In a prospective study, measurements were taken before and after 24 hours of exposure to topical GTN.
  
  
  RESULTS
  Reproducibility of vein diameter measurement was demonstrated. Basilic veins were larger than cephalic veins, but exposure to GTN ointment for 24 hours was not associated with measurable venodilatation.
  
  
  CONCLUSIONS
  Ultrasonography enabled noninvasive measurement of intraluminal vein diameter. It is unlikely that GTN prevents thrombophlebitis in superficial arm veins by causing venodilatation.
authors.affiliation: General Infirmary at Leeds, UK.
authors.forename: N J
authors.initials: NJ
authors.lastname: Everitt
mesh_terms: D001132:Arm / Q000098:blood supply; D006801:Humans; D008297:Male; D005996:Nitroglycerin / Q000008:administration & dosage / Q000494:pharmacology*; D009824:Ointments; D010288:Parenteral Nutrition; D011446:Prospective Studies; D015203:Reproducibility of Results; D014463:Ultrasonography; D014664:Vasodilation / Q000187:drug effects*; D014665:Vasodilator Agents / Q000494:pharmacology*; D014680:Veins / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000502:physiology
chemical_list: D009824:Ointments; D014665:Vasodilator Agents; D005996:Nitroglycerin