title: Therapeutic hypothermia and vasopressor dependency after cardiac arrest.
abstract: OBJECTIVE
  Clinical trials of therapeutic hypothermia (TH) after cardiac arrest excluded patients with persistent hemodynamic instability after return of spontaneous circulation (ROSC), and thus equipoise may exist regarding use of TH in these patients. Our objective was to determine if TH is associated with worsening hemodynamic instability among patients who are vasopressor-dependent after ROSC.
  
  
  METHODS
  We performed a prospective observational study in vasopressor-dependent post-cardiac arrest patients. Inclusion criteria were age >17, non-trauma cardiac arrest, comatose after ROSC, and persistent vasopressor dependence. The decision to initiate TH (33-34 ° C) was made by the treating physician. We measured cumulative vasopressor index (CVI) and mean arterial pressure (MAP) every 15 min during the first 6h after ROSC. The outcome measures were change in CVI (primary outcome) and MAP (secondary outcome) over time. We graphed median CVI and MAP over time for the treated and not treated cohorts, and used propensity adjusted repeated measures mixed models to test for an association between TH induction and change in CVI or MAP over time.
  
  
  RESULTS
  Seventy-five post-cardiac arrest patients were included (35 treated; 40 not treated). We observed no major differences in CVI or MAP over time between the treated and not treated cohorts. In the mixed models we found no statistically significant association between TH induction and changes in CVI or MAP.
  
  
  CONCLUSIONS
  In patients with vasopressor-dependency after cardiac arrest, the induction of hypothermia was not associated with a decrease in mean arterial pressure or increase in vasopressor requirement.
authors.affiliation: Department of Emergency Medicine, Cooper University Hospital, Camden, NJ, United States. roberts-brian-w@cooperhealth.edu
authors.forename: Brian W
authors.initials: BW
authors.lastname: Roberts
authors.forename: J Hope
authors.initials: JH
authors.lastname: Kilgannon
authors.forename: Michael E
authors.initials: ME
authors.lastname: Chansky
authors.forename: Alan E
authors.initials: AE
authors.lastname: Jones
authors.forename: Neil
authors.initials: N
authors.lastname: Mittal
authors.forename: Barry
authors.initials: B
authors.lastname: Milcarek
authors.forename: Joseph E
authors.initials: JE
authors.lastname: Parrillo
authors.forename: Stephen
authors.initials: S
authors.lastname: Trzeciak
mesh_terms: D062186:Arterial Pressure / Q000187:drug effects*; D005260:Female; D005500:Follow-Up Studies; D006323:Heart Arrest / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D007036:Hypothermia, Induced / Q000379:methods*; D002534:Hypoxia, Brain / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors; D014662:Vasoconstrictor Agents / Q000627:therapeutic use*
chemical_list: D014662:Vasoconstrictor Agents