Targeted temperature management (TTM) at 32 °C–36 °C improves patient outcomes following out-of-hospital cardiac arrest (OHCA). TTM using automated temperature management devices with feedback systems (TFDs) is recommended, but the equipment is often unavailable. This study aimed to investigate therapeutic relations between targeted temperatures and TFDs on the outcomes of OHCA patients with TTM.

This multicenter study analyzed nontraumatic OHCA registry data between October 2015 and June 2020 from 29 institutions. Patients were classified into four groups based on targeted temperatures and TFD implementation: TTM at 33 °C with TFD (33TFD), TTM at 36 °C with TFD (36TFD), TTM at 33 °C without TFD (33NTFD), and TTM at 36 °C without TFD (36NTFD). Clinical outcomes were survival till hospital discharge and neurological status at discharge.

A total of 938 patients were included in the analysis. There was an independent association between the 33NTFD patients with the least survival and the worst neurological outcomes among the four groups after adjustment for covariates. However, no significant differences were observed in survival and neurological outcomes among the 33TFD, 36TFD, and 36NTFD groups after adjusting for covariates. Compared to 33NTFD, 36NTFD patients exhibited significantly higher adjusted ORs for survival and favorable neurological status at hospital discharge.

In OHCA patients receiving TTM without TFDs, the adjusted predicted probability of survival and good neurological outcomes at hospital discharge was greater for TTM at 36 °C than that at 33 °C. This suggests that a TTM of 36 °C rather than 33 °C is associated with more favorable clinical outcomes if TFDs are unavailable.