title: The pharmacokinetics of intraosseous atropine in hypovolemic swine.
abstract: OBJECTIVE
  Compare the pharmacokinetics of atropine administered via the intravenous (IV), intramuscular (IM), and intraosseous (IO) routes in a normovolemic and hypovolemic swine model.
  
  
  METHODS
  Prospective, between subjects, experimental study.
  
  
  METHODS
  Vivarium.
  
  
  METHODS
  Yorkshire-cross swine (N = 36).
  
  
  METHODS
  Atropine was administered via IV, IM, or IO routes to normovolemic and hypovolemic swine. Blood samples were drawn at regular intervals after atropine administration and analyzed for plasma atropine concentration. Pharmacokinetic parameters were obtained from modeling the plasma concentrations.
  
  
  METHODS
  Pharmacokinetic parameters, maximum concentration (Cmax) and time to maximum concentration (Tmax).
  
  
  RESULTS
  The IV and IO groups in both the normovolemic and hypovolemic models reached peak plasma concentration immediately and had a very rapid distribution phase with no apparent absorption phase for the IO groups. Peak plasma concentration and time to reach peak concentration were both significantly lower for the IM groups. There was a significant increase in absorption time with IM administration in the hypovolemic model compared to the normovolemic model.
  
  
  CONCLUSIONS
  The IO route is an effective method of administering atropine and is comparable to the IV route even under conditions of significant hemorrhage. Therapeutic levels of atropine may be delayed and possibly difficult to obtain via IM injection in the presence of hypovolemic shock.
authors.affiliation: Department of Anesthesia and Operative Services, Madigan Army Medical Center, Joint Base Lewis-McChord, Washington.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Yost
authors.affiliation: US Army Graduate Program in Anesthesia Nursing, Fort Sam Houston, Texas.
authors.forename: Phillip
authors.initials: P
authors.lastname: Baldwin
authors.affiliation: US Army Graduate Program in Anesthesia Nursing, Fort Sam Houston, Texas.
authors.forename: Sarah
authors.initials: S
authors.lastname: Bellenger
authors.affiliation: US Army Graduate Program in Anesthesia Nursing, Fort Sam Houston, Texas.
authors.forename: Freida
authors.initials: F
authors.lastname: Bradshaw
authors.affiliation: US Army Graduate Program in Anesthesia Nursing, Fort Sam Houston, Texas.
authors.forename: Edna
authors.initials: E
authors.lastname: Causapin
authors.affiliation: US Army Graduate Program in Anesthesia Nursing, Fort Sam Houston, Texas.
authors.forename: Richelle
authors.initials: R
authors.lastname: Demotica
authors.affiliation: US Army Graduate Program in Anesthesia Nursing, Fort Sam Houston, Texas.
authors.forename: Michael
authors.initials: M
authors.lastname: Livingston
authors.affiliation: US Army Graduate Program in Anesthesia Nursing, Fort Sam Houston, Texas.
authors.forename: Cynthia
authors.initials: C
authors.lastname: Lee
authors.affiliation: Veteran Anesthesia Services, San Antonio, Texas.
authors.forename: Brian
authors.initials: B
authors.lastname: Gegel
authors.affiliation: Research Scientist, Geneva Foundation, Tacoma, Washington.
authors.forename: James
authors.initials: J
authors.lastname: Burgert
authors.affiliation: Pharmacokinetics Lab, University of Washington, Seattle, Washington.
authors.forename: Adam
authors.initials: A
authors.lastname: Claessens
authors.affiliation: Director of Research and Professor, US Army Graduate Program in Anesthesia Nursing, Fort Sam Houston, Texas.
authors.forename: Don
authors.initials: D
authors.lastname: Johnson
authors.affiliation: Department of Anesthesia and Operative Services, Madigan Army Medical Center, Joint Base Lewis-McChord, Washington.
authors.forename: Michael
authors.initials: M
authors.lastname: Loughren
mesh_terms: D000818:Animals; D001285:Atropine / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics* / Q000627:therapeutic use; D020896:Hypovolemia / Q000188:drug therapy* / Q000503:physiopathology*; D017148:Infusions, Intraosseous; D007262:Infusions, Intravenous; D007273:Injections, Intramuscular; D018727:Muscarinic Antagonists / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics / Q000627:therapeutic use; D011446:Prospective Studies; D013552:Swine
chemical_list: D018727:Muscarinic Antagonists; D001285:Atropine