Differential Effectiveness of Hypothermic Targeted Temperature Management According to the Severity of Post-Cardiac Arrest Syndrome

Abstract

International guidelines recommend targeted temperature management (TTM) to improve the neurological outcomes in adult patients with post-cardiac arrest syndrome (PCAS). However, it still remains unclear if the lower temperature setting (hypothermic TTM) or higher temperature setting (normothermic TTM) is superior for TTM. According to the most recent large randomized controlled trial (RCT), hypothermic TTM was not found to be associated with superior neurological outcomes than normothermic TTM in PCAS patients. Even though this represents high-quality evidence obtained from a well-designed large RCT, we believe that we still need to continue investigating the potential benefits of hypothermic TTM. In fact, several studies have indicated that the beneficial effect of hypothermic TTM differs according to the severity of PCAS, suggesting that there may be a subgroup of PCAS patients that is especially likely to benefit from hypothermic TTM. Herein, we summarize the results of major RCTs conducted to evaluate the beneficial effects of hypothermic TTM, review the recent literature suggesting the possibility that the therapeutic effect of hypothermic TTM differs according to the severity of PCAS, and discuss the potential of individualized TTM.

Combination of Hyperoxygenation and Targeted Temperature Management Improves Functional Outcomes of Post Cardiac Arrest Syndrome Irrespective of Causes of Arrest in Rats

“…Second, hyperoxygenation can promote recovery by enhancing tissue oxygen delivery to ensure organ function and viability (48,49), whereas TTM can attenuate PCAS by reducing the excessive accumulation of ROS and enhancing antioxidant activity (50). Third, the efficacy of hyperoxygenation and TTM is related to etiology when used alone (24,51), whereas the combination can improve tissue oxygen supply accompanied by reduced oxidative stress damage, therefore maximizing treatment effectiveness (14). This is the first study to investigate the effect of hyperoxygenation and TTM on PCAS in both asphyxial and dysrhythmic CA rat models.…”

External validation of the rCAST for patients after in-hospital cardiac arrest: a multicenter retrospective observational study

“…Moreover, our previous study showed that the treatment effect size was different by score points on the rCAST and that the patient group that is particularly likely to derive benefit from TTM at the lower setting temperature is the group with PCAS of moderate-severity grade on rCAST 23 . Although further research is needed, this may also be applicable to IHCA patients, indicating that the risk classification with the rCAST before TTM may be helpful in identifying IHCA patients who benefit most from TTM at the lower setting temperature 24 .…”