title: An optimal dual-size vial system for the cost-effective usage of Adenoscan.
abstract: BACKGROUND
  Adenoscan (Fujisawa USA, Inc., Deerfield, Ill.) has been initially packaged in a 30 ml glass vial for single use only because it contains no preservative. This restricted usage has generated considerable waste and high cost for the patient. Although the new 20 ml vial of Adenoscan provides some reduction in waste, the savings offered by the 20 ml and 30 ml vial system is still not optimal. The purpose of this study was to investigate an optimal dual-size vial system that would provide limited amounts of waste while maintaining its practicality to satisfy different patient populations.
  
  
  RESULTS
  The least waste for each potential combination (n = 344) of two vials was calculated by assuming that patient weights (30 to 200 kg) follow a normal distribution. The 6 ml and 15 ml vial combination had the least expected waste for lighter patient populations, and the 9 ml and 15 ml vial system had the least expected waste for heavier populations. The calculated wastes for 4207 patients (83 +/- 19 kg) undergoing adenosine stress myocardial perfusion studies at the Mayo Clinic were 10.5 +/- 9.3 ml (30 ml vial), 5.1 +/- 2.9 ml (20 ml and 30 ml vial system), 1.6 +/- 1.0 ml (6 ml and 15 ml vial system), and 1.8 +/- 1.2 ml (9 ml and 15 ml vial system).
  
  
  CONCLUSIONS
  In general, both the 6 ml and 15 ml and 9 ml and 15 ml vial systems perform better than either the single 30 ml vial or the 20 ml and 30 ml vial system. Furthermore, the 6 ml and 15 ml vial combination offers the lowest expected waste for the actual patient population that underwent the adenosine stress myocardial perfusion imaging studies at our institution.
authors.affiliation: Nuclear Medicine, Department of Diagnostic Radiology, Mayo Clinic, Rochester, Minn 55905, USA. jhung@mayo.edu
authors.forename: J C
authors.initials: JC
authors.lastname: Hung
authors.forename: D W
authors.initials: DW
authors.lastname: Mahoney
authors.forename: D L
authors.initials: DL
authors.lastname: Johnston
authors.forename: R J
authors.initials: RJ
authors.lastname: Gibbons
mesh_terms: D003362:Cost-Benefit Analysis; D004176:Dipyridamole / Q000008:administration & dosage / Q000191:economics; D004349:Drug Packaging / Q000191:economics; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D011877:Radionuclide Imaging
chemical_list: D004176:Dipyridamole