Clinical paperChanging target temperature from 33 °C to 36 °C in the ICU management of out-of-hospital cardiac arrest: A before and after study☆
Introduction
Since the publication of two seminal studies1, 2 over a decade ago, therapeutic hypothermia (32 °C–34 °C) for at least 24 h has been recommended in the post-resuscitation care for comatose survivors of cardiac arrest.3, 4 More recently, the recommended targeted temperature for this treatment was expanded from a range of 32–34 °C to 32–36 °C5, 6 following results from the targeted temperature management (TTM) trial.7 The TTM trial allocated patients to either 32–34 °C or 36 °C, and found no difference in outcomes.
Following publication of the TTM trial, many centres have adopted a target temperature of 36 °C.8, 9, 10 However, achieving a target temperature of 36 °C may be problematic, with a recent study reporting a significant risk of fever in the first 24 h of ICU admission.11
In December 2013, the intensive care unit (ICU) at The Alfred Hospital changed the post-resuscitation target temperature for ventricular fibrillation out-of-hospital cardiac arrest (VF-OHCA) patients from 33 °C to 36 °C. This paper presents the findings of a retrospective cohort study of patients admitted before and after this change which examined compliance with the targeted temperature and patient outcomes.
Section snippets
Setting
This study was performed on consecutive, non-traumatic, VF-OHCA patients admitted to The Alfred Hospital ICU (Melbourne, Australia) between January 2013 and August 2015. The Alfred Hospital is a quaternary referral hospital in Melbourne, Australia, with cardiac services including interventional cardiology, extra-corporeal membrane oxygenation (ECMO) and cardiac transplantation.12 This study was approved by The Alfred Hospital Human Research and Ethics Committee.
Ambulance response to OHCA
Results
Over the study period, 76 VF-OHCA cases were admitted to the ICU (24 before and 52 after the TTM change). Patient demographics and cardiac arrest features were similar between the two periods (Table 1). The overall median time from cardiac arrest to return of spontaneous circulation (ROSC) was similar between the two periods (20 vs. 22 min, p = 0.98).
A similar number of patients underwent urgent cardiac catheterisation, but there were more patients treated with veno-arterial ECMO in the 33 °C
Discussion
The change from a post-arrest temperature target of 33 °C to 36 °C in our ICU has been associated with significant non-compliance with achieving the target temperature and this may be associated with poorer patient outcomes. Our results are noteworthy given that many ICUs have changed TTM practice.8, 9, 10 For example, a recent 10-year audit of ICUs in the United Kingdom reported a sudden drop in 2014 to the proportion of cardiac arrest patients with a lowest temperature recording of <34 °C (39%
Conflict of interest statement
None.
Acknowledgements
Drs Bray (#1069985), Stub (#1090302) and Mitra (#1072579) are supported by National Health and Medical Research (NHMRC)/Heart Foundation Fellowships. Dr Bray and Prof Finn receive salary support from the Australian Resuscitation Outcomes Consortium (Aus-ROC) NHMRC funded Centre of Research Excellence (#1029983).
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2023, Critical Care ClinicsCitation Excerpt :Early priority is effective post-CA care to identify and treat the precipitating cause of arrest, and to prevent rearrest.1 The flow chart (Fig. 1) summarizes our approach to post-CA management.1–26 Patients who achieve ROSC should be rapidly evaluated for coronary intervention and targeted temperature management (TTM) to prevent secondary brain injury.
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A Spanish translated version of the abstract of this article appears as Appendix in the final online version at http://dx.doi.org/10.1016/j.resuscitation.2017.01.016.