Department of Emergency Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea; Department of Emergency Medicine, Samcheok Medical Center, Samcheok, Kangwon, 25920, Republic of Korea.
Department of Emergency Medicine, School of Medicine, Kangwon National University, Chuncheon, Gangwon, 24341, Republic of Korea.
J Therm Biol. 2020 Jan;87:102466. doi: 10.1016/j.jtherbio.2019.102466. Epub 2019 Nov 26.
To date, hypothermia has focused on improving rates of resuscitation to increase survival in patients sustaining cardiac arrest (CA). Towards this end, the role of body temperature in neuronal damage or death during CA needs to be determined. However, few studies have investigated the effect of regional temperature variation on survival rate and neurological outcomes. In this study, adult male rats (12 week-old) were used under the following four conditions: (i) whole-body normothermia (37 ± 0.5 °C) plus (+) no asphyxial CA, (ii) whole-body normothermia + CA, (iii) whole-body hypothermia (33 ± 0.5 °C)+CA, (iv) body hypothermia/brain normothermia + CA, and (v) brain hypothermia/body normothermia + CA. The survival rate after resuscitation was significantly elevated in groups exposed to whole-body hypothermia plus CA and body hypothermia/brain normothermia plus CA, but not in groups exposed to whole-body normothermia combined with CA and brain hypothermia/body normothermia plus CA. However, the group exposed to hypothermia/brain normothermia combined with CA exhibited higher neuroprotective effects against asphyxial CA injury, i.e. improved neurological deficit and neuronal death in the hippocampus compared with those involving whole-body normothermia combined with CA. In addition, neurological deficit and neuronal death in the group of rat exposed to brain hypothermia/body normothermia and CA were similar to those in the rats subjected to whole-body normothermia and CA. In brief, only brain hypothermia during CA was not associated with effective survival rate, neurological function or neuronal protection compared with those under body (but not brain) hypothermia during CA. Our present study suggests that regional temperature in patients during CA significantly affects the outcomes associated with survival rate and neurological recovery.
迄今为止,低温治疗主要集中在提高复苏率以增加心脏骤停(CA)患者的存活率。为此,需要确定体温在 CA 期间神经元损伤或死亡中的作用。然而,很少有研究调查局部温度变化对存活率和神经结局的影响。在这项研究中,使用成年雄性大鼠(12 周龄)在以下四种情况下进行:(i)全身正常体温(37 ± 0.5°C)加(+)无窒息性 CA,(ii)全身正常体温+CA,(iii)全身低温(33 ± 0.5°C)+CA,(iv)全身低温/脑正常体温+CA,和(v)脑低温/体正常体温+CA。在复苏后,暴露于全身低温加 CA 和全身低温/脑正常体温加 CA 的组的存活率显著提高,但暴露于全身正常体温与 CA 联合的组和脑低温/体正常体温与 CA 联合的组则不然。然而,与全身正常体温加 CA 联合的组相比,全身低温/脑正常体温加 CA 联合的组对窒息性 CA 损伤具有更高的神经保护作用,即改善了海马中的神经功能缺损和神经元死亡。此外,在脑低温/体正常体温和 CA 暴露的大鼠组中,神经功能缺损和神经元死亡与全身正常体温和 CA 暴露的大鼠相似。总之,与 CA 期间的全身(而非脑)低温相比,只有 CA 期间的脑低温与有效存活率、神经功能或神经元保护无关。我们的研究表明,患者在 CA 期间的局部温度会显著影响与存活率和神经恢复相关的结果。