New Recommendations for Use of Targeted Temperature Management in Critical Care Settings
For intensivists seeking guidance, a recent report in the Annals of Intensive Care gives detailed recommendations on the use of targeted temperature management (TTM) for critically ill patients. The report, co-authored by several groups of French physicians, examines the evidence of TTM in a variety of clinical situations, provides 30 specific recommendations, and rates the strength of evidence supporting each recommendation. The result is a thorough yet practical set of guidelines for front-line practitioners.
TTM In Cardiac Arrest
Of the 30 recommendations made by the panel, three were given a strong rating based on the evidence. A strong rating required the agreement of 70% of the voting experts.
One of the strong recommendations was to use TTM to improve survival with good neurological outcome in patients resuscitated from out-of-hospital cardiac arrest (OHCA) with shockable cardiac rhythm (ventricular fibrillation or pulseless ventricular tachycardia) and who remain comatose after return of spontaneous circulation (ROSC). An earlier consensus statement from the American Heart Association agrees with this recommendation, and the efficacy of this intervention in this group is also supported by a more recent meta-analysis.
For those patients who presented with a non-shockable rhythm (asystole or pulseless electrical activity) and remain comatose after ROSC, the panel gave a weak recommendation to consider TTM. Most studies show little, if any effect in this group, but based on the poor prognosis in this subgroup and the lack of therapeutic alternatives, the panel felt that TTM could be beneficial.
For those suffering an in-hospital cardiac arrest (IHCA), the panel gave a recommendation to consider TTM. But given the lack of data in this population, the recommendation consisted only of expert opinion.
As for the specifics of TTM, the panel recommended a range of 32°-36° C, and did not suggest using large volumes of cold saline solution during transport to the hospital. These recommendations are also supported by the AHA consensus paper and another recent meta-analysis.
Pediatric patients with cardiac arrest present a different picture than adults. The French panel did not recommend using hypothermia in this group, and instead recommended using normothermia to improve neurological outcome in all pediatric cardiac arrest.
TTM After Traumatic Brain Injury
The panel gave a weak recommendation to use TTM at 35°-37° C in patients with severe traumatic brain injury (TBI) to control intracranial pressure (ICP) and improve survival with good neurological outcome. The data showed no improved outcomes, but there are demonstrably poor outcomes associated with hyperthermia in this group, so the panel supported the use of TTM.
A weak recommendation was also given for TTM at 34°-35° C to lower ICP in TBI patients with refractory intracranial hypertension despite medical treatments. The evidence suggested that temperatures below 34° C were detrimental in this population.
The panel issued a strong recommendation to not use TTM at 32°-34° C in children to lower ICP or improve neurological outcome. Although hyperthermia is also associated with poor outcomes in children, as in adults, the data suggested that moderate hypothermia in children leads to low arterial blood pressure and low cerebral perfusion.
Part 2 coming Thursday, May 31st.