title: The effect of mild therapeutic hypothermia on good neurological recovery after out-of-hospital cardiac arrest according to location of return of spontaneous circulation: a nationwide observational study.
abstract: BACKGROUND
  Mild therapeutic hypothermia (MTH) has been known to be associated with good neurological recovery after out-of-hospital cardiac arrest (OHCA). Prehospital return of spontaneous circulation (P-ROSC) is associated with better hospital outcomes than ROSC at emergency department (ED-ROSC). The study aims to examine the association between MTH by location of ROSC and good neurological recovery after OHCA.
  
  
  METHODS
  Adult OHCA cases with presumed cardiac etiology who survived to hospital admission were collected from a nationwide cardiac registry between 2008 and 2013. MTH was defined as a case receiving hypothermia procedure regardless of procedure method. Primary outcome was good neurological recovery with cerebral performance category score of 1 and 2. Multivariable logistic regression analysis was performed adjusting for potential confounders with an interaction term between MTH and location of ROSC to calculate adjusted odds ratios (AORs) and 95% confidence intervals (CIs).
  
  
  RESULTS
  Among 11,158 patients survived to admission, good neurological recovery was 23.6% (399/1691) in MTH vs. 15.0% (1400/9316) in non-MTH (p<0.001), and 58.2% (1074/1864) in P-ROSC vs. 7.9% (725/9161) in ED-ROSC (p<0.001). There was a significant association between MTH and good neurological recovery (AOR=1.32, 95% CI=1.11-1.57). In the interaction model, AOR of MTH and interaction effect with P-ROSC and ED-ROSC was 0.78 (0.58-2.70) and 1.68 (1.34-1.98), respectively.
  
  
  CONCLUSIONS
  MTH was significantly associated with good neurological recovery among OHCA survivors. In the interaction model, MTH showed significant benefits in patient group with ROSC at ED, not in P-ROSC group.
authors: Department of Emergency Medicine, Seoul National University College of Medicine, South Korea. Electronic address: zorbathekorean@gmail.com.
authors: Kwang Soo
authors: KS
authors: Bae
authors: Department of Emergency Medicine, Seoul National University College of Medicine, South Korea. Electronic address: shinsangdo@medimail.co.kr.
authors: Sang Do
authors: SD
authors: Shin
authors: Laboratory of Emergency Medical Services, Seoul National University Hospital Biomedical Research Institute, South Korea. Electronic address: Ro.youngsun@gmail.com.
authors: Young Sun
authors: YS
authors: Ro
authors: Department of Emergency Medicine, Seoul National University College of Medicine, South Korea. Electronic address: skciva@gmail.com.
authors: Kyoung Jun
authors: KJ
authors: Song
authors: Department of Emergency Medicine, Seoul National University College of Medicine, South Korea. Electronic address: ironlyj@gmail.com.
authors: Eui Jung
authors: EJ
authors: Lee
authors: Department of Emergency Medicine, Seoul National University College of Medicine, South Korea. Electronic address: eyeblack99@gmail.com.
authors: Yu Jin
authors: YJ
authors: Lee
authors: Department of Emergency Medicine, Seoul National University College of Medicine, South Korea. Electronic address: suhgil@snu.ac.kr.
authors: Gil Joon
authors: GJ
authors: Suh
authors: Department of Emergency Medicine, Seoul National University College of Medicine, South Korea. Electronic address: yhkwak@snuh.org.
authors: Young Ho
authors: YH
authors: Kwak
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016887:Cardiopulmonary Resuscitation; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D007036:Hypothermia, Induced; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000401:mortality* / Q000503:physiopathology / Q000628:therapy*; D020127:Recovery of Function; D056910:Republic of Korea; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
keywords: Cardiac arrest; Hypothermia; Outcomes; Return of spontaneous circulation