title: Prehospital lactated ringer's solution treatment and survival in out-of-hospital cardiac arrest: a prospective cohort analysis.
abstract: BACKGROUND
  No studies have evaluated whether administering intravenous lactated Ringer's (LR) solution to patients with out-of-hospital cardiac arrest (OHCA) improves their outcomes, to our knowledge. Therefore, we examined the association between prehospital use of LR solution and patients' return of spontaneous circulation (ROSC), 1-month survival, and neurological or physical outcomes at 1 month after the event.
  
  
  RESULTS
  We conducted a prospective, non-randomized, observational study using national data of all patients with OHCA from 2005 through 2009 in Japan. We performed a propensity analysis and examined the association between prehospital use of LR solution and short- and long-term survival. The study patients were ≥18 years of age, had an OHCA before arrival of EMS personnel, were treated by EMS personnel, and were then transported to hospitals. A total of 531,854 patients with OHCA met the inclusion criteria. Among propensity-matched patients, compared with those who did not receive pre-hospital intravenous fluids, prehospital use of LR solution was associated with an increased likelihood of ROSC before hospital arrival (odds ratio [OR] adjusted for all covariates [95% CI] = 1.239 [1.146-1.339] [p<0.001], but with a reduced likelihood of 1-month survival with minimal neurological or physical impairment (cerebral performance category 1 or 2, OR adjusted for all covariates [95% CI] = 0.764 [0.589-0.992] [p = 0.04]; and overall performance category 1 or 2, OR adjusted for all covariates [95% CI] = 0.746 [0.573-0.971] [p = 0.03]). There was no association between prehospital use of LR solution and 1-month survival (OR adjusted for all covariates [95% CI] = 0.960 [0.854-1.078]).
  
  
  CONCLUSIONS
  In Japanese patients experiencing OHCA, the prehospital use of LR solution was independently associated with a decreased likelihood of a good functional outcome 1 month after the event, but with an increased likelihood of ROSC before hospital arrival. Prehospital use of LR solution was not associated with 1-month survival. Further study is necessary to verify these findings. Please see later in the article for the Editors' Summary.
authors: Kyushu University Graduate School of Medicine, Department of Health Services Management and Policy, Fukuoka, Japan. hagihara@hsmp.med.kyushu-u.ac.jp
authors: Akihito
authors: A
authors: Hagihara
authors: Manabu
authors: M
authors: Hasegawa
authors: Takeru
authors: T
authors: Abe
authors: Yoshifumi
authors: Y
authors: Wakata
authors: Takashi
authors: T
authors: Nagata
authors: Yoshihiro
authors: Y
authors: Nabeshima
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D004632:Emergency Medical Services / Q000379:methods*; D005260:Female; D005440:Fluid Therapy / Q000009:adverse effects / Q000401:mortality; D006801:Humans; D007262:Infusions, Intravenous; D007552:Isotonic Solutions / Q000008:administration & dosage* / Q000009:adverse effects; D007564:Japan; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D058687:Out-of-Hospital Cardiac Arrest / Q000175:diagnosis / Q000401:mortality / Q000628:therapy*; D057216:Propensity Score; D011446:Prospective Studies; D012042:Registries; D000077325:Ringer's Lactate; D018570:Risk Assessment; D012307:Risk Factors; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D007552:Isotonic Solutions; D000077325:Ringer's Lactate