Grand Johannes, Hassager Christian, Bro-Jeppesen John, Gustafsson Finn, Møller Jacob Eifer, Boesgaard Søren, Nielsen Niklas, Kjaergaard Jesper
Department of Cardiology, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark.
Department of Anaesthesia and Intensive Care, Helsingborg Hospital, Helsingborg, Sweden.
Ther Hypothermia Temp Manag. 2021 Sep;11(3):170-178. doi: 10.1089/ther.2020.0013. Epub 2020 Jun 23.
Targeted temperature management (TTM) exerts substantial impact on hemodynamic function in out-of-hospital cardiac arrest (OHCA) patients. Whole-body oxygen consumption (VO) and delivery (DO) have not previously been investigated in a clinical setting during TTM at different levels of temperature after OHCA. A substudy of 151 patients randomized at a single center in the TTM-trial, where patients were randomly assigned TTM at 33°C (TTM33) or 36°C (TTM36) for 24 hours. We calculated VO according to the principle of Fick (VO = cardiac outputarteriovenous oxygen content difference). DO was calculated as cardiac outputarterial oxygen content. Cardiac output was measured by pulmonary artery catheter with thermodilution. Arteriovenous oxygen content difference was calculated from arterial and mixed venous oxygen saturation and hemoglobin. Oxygen extraction ratio = VO/DO. At 24 hours, the VO was 169 ± 59 mL O per minute in TTM33 and 217 ± 53 mL O per minute in TTM36 ( < 0.0001). During 24 hours of TTM, the overall difference was 53 mL O minute (95% confidence interval [CI]: 31-74, < 0.0001). After rewarming at 36 and 48 hours, there was no difference in VO between the groups. DO was overall 277 mL O per minute (95% CI: 175-379, < 0.0001) higher in the TTM36-group during TTM. Oxygen extraction ratio during TTM was not significantly different between the two groups (2% [95% CI: -0.1 to 5, = 0.09]). VO during the first 36 hours after OHCA correlated significantly with temperature, and VO was 19 mL O per minute lower per degree reduction in temperature (95% CI: 15-22), < 0.0001. TTM at 33°C compared to 36°C after OHCA is associated with significantly lower VO and DO, however, oxygen extraction ratio was not significantly different. For each degree lower body temperature, the VO fell by 19 mL O per minute.
目标温度管理（TTM）对院外心脏骤停（OHCA）患者的血流动力学功能有重大影响。此前尚未在临床环境中研究OHCA后不同温度水平的TTM期间全身氧消耗（VO）和输送（DO）情况。一项针对151例患者的子研究，这些患者在TTM试验中于单个中心随机分组，患者被随机分配接受33°C（TTM33）或36°C（TTM36）的TTM治疗24小时。我们根据菲克原理计算VO（VO = 心输出量×动静脉氧含量差）。DO计算为心输出量×动脉氧含量。心输出量通过热稀释肺动脉导管测量。动静脉氧含量差由动脉和混合静脉血氧饱和度及血红蛋白计算得出。氧摄取率 = VO/DO。在24小时时，TTM33组的VO为每分钟169±59 mL O，TTM36组为每分钟217±53 mL O（P < 0.0001）。在TTM的24小时期间，总体差异为每分钟53 mL O（95%置信区间[CI]：31 - 74，P < 0.0001）。在36小时和48小时复温后，两组之间的VO没有差异。在TTM期间，TTM36组的DO总体上比TTM33组每分钟高277 mL O（95% CI：175 - 379，P < 0.0001）。两组在TTM期间的氧摄取率没有显著差异（2% [95% CI： - 0.1至5，P = 0.09]）。OHCA后最初36小时内的VO与温度显著相关，温度每降低1度，VO每分钟降低19 mL O（95% CI：15 - 22，P < 0.0001）。与36°C相比，OHCA后33°C的TTM与显著更低的VO和DO相关，然而，氧摄取率没有显著差异。体温每降低1度，VO每分钟下降19 mL O。
