Duration of well-controlled core temperature correlates with neurological outcome in patients with post-cardiac arrest syndrome.
OBJECTIVE
Detailed procedures for optimal therapeutic hypothermia (TH) have yet to be established. We examined how duration of well-controlled core temperature within the first 24 hours after cardiac arrests (CA) correlated with neurological outcomes of successfully resuscitated out-of-hospital CA (OHCA) patients.


METHODS
OHCA patients who survived over 24 hours and treated with TH were included. Core temperature was measured every hour. Physicians intended to maintain temperature at 33 °C ± 1 °C for 24 hours. Cerebral performance categories (CPC) of patients at 6 months were recorded and patients were retrospectively divided into favorable (CPC1,2) and poor (CPC3-5) neurological outcome groups. Total time while the core temperature reached to 33 °C ± 1 °C within the first 24 hours after CA was measured and this duration was defined that of well-controlled temperature. receiver-operating characteristic analysis was performed on duration of well-controlled temperature to select the optimal cutoff value. Neurological outcome predictors were investigated by logistic regression analysis.


RESULTS
Fifty-six patients were included. Optimal cutoff value of duration of well-controlled temperature was 18 hours. Ratio of male sex, witnessed by emergency medical service (EMS) personnel, first electrocardiogram as shockable, and duration of well-controlled core temperature ≥ 18 h of favorable neurological outcome group (n = 21) were significantly larger than that of poor neurological outcome group (n = 35). Logistic regression analysis identified "witnessed by EMS", "performed bystander CPR," and "the duration ≥ 18 h" as independent predictors of favorable neurological outcome.


CONCLUSIONS
TH maintained at target temperature of 33 °C ± 1 °C over 18 hours independently correlated with favorable neurological outcome. Therefore, stable core temperature control may improve neurological outcome of successfully resuscitated OHCA.
Department of Emergency and Critical Care Medicine, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba 260-8677, Japan. shino@gk9.so-net.ne.jp
Koichiro
K
Shinozaki
Shigeto
S
Oda
Tomohito
T
Sadahiro
Masataka
M
Nakamura
Yo
Y
Hirayama
Eizo
E
Watanabe
Yoshihisa
Y
Tateishi
Kasuya
K
Nakanishi
Nobuya
N
Kitamura
Hiroyuki
H
Hirasawa
D000368:Aged; D001831:Body Temperature; D005260:Female; D006801:Humans; D007036:Hypothermia, Induced; D002534:Hypoxia, Brain / Q000209:etiology / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D058687:Out-of-Hospital Cardiac Arrest / Q000150:complications / Q000628:therapy*; D012189:Retrospective Studies; D016896:Treatment Outcome