title: Impact of temperature exposure on stability of drugs in a real-world out-of-hospital setting.
abstract: OBJECTIVE
  The aim of this study is to determine the content of 5 important emergency medical services (EMS) drugs after being stored at the recommended refrigerated temperature, room temperature, or in an emergency physician transport vehicle operating under real-world working conditions.
  
  
  METHODS
  Adrenaline hydrochloride, cisatracurium besylate, lorazepam, methylergonovine maleate, and succinylcholine chloride were stored for 1 year under the 3 conditions. For each storage condition, samples of the drugs were taken after 1, 2, 3, and 4 weeks and after 2, 4, 6, 8, 10, and 12 months. For adrenaline hydrochloride, however, the samples were taken after 1, 2, 4, 6, 8, 10, and 12 months. The samples were analyzed with a validated high-performance liquid chromatography assay. A drug was considered stable if its content was above 90%.
  
  
  RESULTS
  Adrenaline hydrochloride and methylergonovine maleate remained stable for 1 year at room temperature and in the emergency physician transport vehicle. At room temperature and in the emergency physician transport vehicle, lorazepam became unstable within 4 weeks. Succinylcholine chloride was stable for 2 months at room temperature and for 1 month in the emergency physician transport vehicle. Cisatracurium besylate became unstable within 4 months at room temperature. However, it remained stable for 4 months in the emergency physician transport vehicle.
  
  
  CONCLUSIONS
  When stored at room temperature or in the emergency physician transport vehicle, lorazepam became unstable within weeks, whereas succinylcholine chloride and cisatracurium besylate became unstable within months. Adrenaline hydrochloride and methylergonovine maleate remained stable for several months, even under room temperature and emergency physician transport vehicle conditions. Thus, real-world EMS working conditions pose challenges for maintaining optimal efficacy of these important EMS drugs.
authors.affiliation: Pharmacy Department, UZ Leuven and Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium. Electronic address: sabrina.dewinter@uzleuven.be.
authors.forename: Sabrina
authors.initials: S
authors.lastname: De Winter
authors.forename: Peter
authors.initials: P
authors.lastname: Vanbrabant
authors.forename: N T Tuong
authors.initials: NT
authors.lastname: Vi
authors.forename: Xiaolan
authors.initials: X
authors.lastname: Deng
authors.forename: Isabel
authors.initials: I
authors.lastname: Spriet
authors.forename: Ann
authors.initials: A
authors.lastname: Van Schepdael
authors.forename: Jean-Bernard
authors.initials: JB
authors.lastname: Gillet
mesh_terms: D000552:Ambulances; D001279:Atracurium / Q000031:analogs & derivatives / Q000032:analysis / Q000592:standards; D002851:Chromatography, High Pressure Liquid; D004355:Drug Stability; D004356:Drug Storage / Q000379:methods / Q000592:standards; D004632:Emergency Medical Services; D004837:Epinephrine / Q000032:analysis / Q000592:standards; D008755:Methylergonovine / Q000032:analysis / Q000592:standards; D013390:Succinylcholine / Q000032:analysis / Q000592:standards; D013696:Temperature; D013997:Time Factors
chemical_list: D001279:Atracurium; D013390:Succinylcholine; C101584:cisatracurium; D008755:Methylergonovine; D004837:Epinephrine