UMEM Educational Pearls

 

Fever has long been understood to be associated with worse outcomes in patients post-cardiac arrest. Whether ascribing to the goal of 33-34°C, 36°C, or simply <38°C, close monitoring and management of core temperatures are a tenet of post-cardiac arrest care.

A recently published study compared the effectiveness of several methods in maintaining temperatures <38°C…

• Both ICHA and OHCA, shockable and unshockable, nontraumatic arrests
• Single center retrospective cohort study looking at 1/2012 – 9/2015
• Treatment and temperatures over first 48 hours

Results:

Maintenance of temp <38°C:

• Antipyretics only group: 57.7% 
• Invasive cooling by intravascular catheter +/- antipyretics:  82.1%

Mean change in temp from baseline:

• Antipyretics only: +1.1°C
• Intravascular alone: -3.4°C
• Antipyretics + Intravascular cooling: -5.2°C

Limitations:

• Varied range of antipyretic dosing per body weight
• No mention of noninvasive cooling methods (cooling pads, ice packs, etc.)
• Patients w/ intravascular cooling likely getting more aggressive care in general
• Not powered for clinical outcomes assessment

 

Bottom Line:

• Antipyretics alone greatly ineffective at preventing fever 
• Even with invasive cooling -- not meeting goal 18% of the time
• With longer ED boarding times nationwide, we must pay active attention to body temperature management and not assume that that we can set it and forget it, even with techniques as invasive as intravascular cooling.

References

 

1. Bernard SA, Gray TW, Buist MD, et al. Treatment of comatose survivors of out-of-hospital cardiac arrest with induced hypothermia. N Engl J Med. 2002 Feb 21;346(8):557-63. doi: 10.1056/NEJMoa003289. 
2. Nielsen N, Wetterslev J, Cronberg T, et al; TTM Trial Investigators. Targeted temperature management at 33°C versus 36°C after cardiac arrest. N Engl J Med. 2013 Dec 5;369(23):2197-206. doi: 10.1056/NEJMoa1310519. 
3. Dankiewicz J, Cronberg T, Lilja G et al; TTM2 Trial Investigators. Hypothermia versus Normothermia after Out-of-Hospital Cardiac Arrest. N Engl J Med. 2021 Jun 17;384(24):2283-2294. doi: 10.1056/NEJMoa2100591.
4. Alnabelsi TS, Faulkner SP, Cook M, Freeman K, Shelton J, Paranzino M, Nerusu S, Smyth SS, Gupta VA. Passive antipyretic therapy is not as effective as invasive hypothermia for maintaining normothermia after cardiac arrest. Am J Emerg Med. 2021 Jul 2;50:202-206. doi: 10.1016/j.ajem.2021.06.069. Epub ahead of print. PMID: 34390903.