Post-Cardiac Arrest: 2025 Guideline Update
The American Heart Association and the European Society for Intensive Care Medicine each updated their post-cardiac arrest guidelines in 2025.
Both were informed by the same evidence review from ILCOR, the international committee advising both AHA and ESICM, but the two sets of guidelines differ in small but interesting ways.
One surprise was the new suggestion (by both societies) for considering head-to-pelvis CT scans on many cardiac arrest survivors, to identify unrecognized etiologies or CPR injuries.
ESICM provided desperately needed guidance on neuroprognostication, including an algorithm with validated good performance in identifying patients with a poor neurologic prognosis; AHA simply (and less helpfully) provided a list of prognostic factors, with no schema in which to apply them.
The two societies covered further ground in their statements’ combined 122 pages, most of which generally reaffirmed usual care. Here are a few of the highlights.
Oxygenation Targets After Cardiac Arrest
The AHA advised using 100% oxygen until patients are stabilized in an ED or ICU, then targeting an oxygen saturation of 90-98% or PaO2 60 to 105 mmHg. They cite randomized trials suggesting harm from either hypoxemia or hyperoxia.
ESICM advised targeting SpO2 of 94 to 98%; they seemed to believe this provided a better cushion against dips into hypoxemia.
Both organizations warned that pulse oximetry is prone to overestimating oxygenation in patients with darker-pigmented skin, placing them at risk for “occult hypoxemia.”
ESICM also recommended targeting normocapnia in ventilated patients (pCO2 35 to 45 mmHg).
Blood Pressure Targets After Cardiac Arrest
The AHA advised MAP ≥65 mmHg; the ESICM advised MAP >60-65 mmHg.
ESICM’s statement addresses the potential need of some patients for higher MAP to preserve cerebral perfusion, given the prevalence of brain edema after cardiac arrest.
Interestingly, the source they reference is a 2023 scientific statement from the American Heart Association and the Neurocritical Care Society which recommended targeting a MAP higher than 80 mmHg in post-cardiac arrest patients:
In ICUs where advanced cerebral monitoring is not in routine use, target a MAP >80 mm Hg unless there are clinical concerns or evidence of adverse consequences (82.6% agreement among the panel).
ESICM also endorsed individualized higher MAP targets in patients with chronic hypertension or ongoing peripheral hypoperfusion when MAP is between 60 and 65 mmHg (e.g. oliguria, lactatemia).
AHA’s guidance does not mention any of this apparent controversy, simply referencing the four randomized trials that have been performed and concluding that
The safety of a lower MAP target (eg, 60–65 mm Hg) has not been evaluated in post–cardiac arrest patients. It is also unknown if a higher MAP target (eg, 80–100 mm Hg) may be beneficial for some patients.
That 2023 joint statement by AHA and NCS was very neurocrit-centric—e.g., also endorsing invasive intracranial pressure monitoring in comatose cardiac arrest survivors with brain edema (81% in agreement). That’s virtually never done in MICUs (and has no evidence to support it).
Avoid Hyperkalemia and Hypokalemia
Both hypokalemia and hyperkalemia are associated with ventricular arrhythmias and are to be avoided, ESICM advised. AHA didn’t address this.
Recent evidence suggests that targeting high-normal serum K+ may be ideal:
When Is Left-Heart Catheterization Indicated After Cardiac Arrest?
The short answer is not usually, but it’s crucial in certain cases:
AHA gives a class 1 (strong) recommendation for emergent left heart catheterization after cardiac arrest with persistent ST-elevations, or (a weaker 2a recommendation) with cardiogenic shock, recurrent ventricular arrhythmias, or significant ongoing myocardial ischemia. This includes comatose patients.
Patients with suspected cardiac cause of arrest without these features should not undergo emergent cath, but should before discharge (strong recommendations).
For cardiogenic shock, ESICM advised restricting left ventricular mechanical support (e.g., intra-aortic balloon pump, ECMO, or Impella™) to those patients who presented to the hospital non-comatose and with obvious cardiac ischemic etiology (e.g., GCS ≥8, with ST-elevation myocardial infarction and < 10 min cardiac arrest).
Temperature Control After Cardiac Arrest
Both organizations continue to promote fever prevention with active temperature control (i.e., automated cooling pads) to ≤37.5° C.
Although induced hypothermia has been officially taken off the recommendations for most post-arrest patients, AHA references two observational studies that show improved outcomes with induced hypothermia for patients with more severe brain injuries. These studies are confounded by clinician selection bias (i.e., which patients they chose to cool), but AHA kept the dream alive for the deep-freezers by giving both hypothermia and normothermia a 2B suggestion for apparent severe brain injury.
Fever prevention was never tested on cardiac arrest patients against true controls (only against patients who were cooled). Its purported benefits are extrapolated from observational cohorts, in which (similar to the findings in ischemic stroke patients) more severe brain injury has been associated with both fevers and bad outcomes.
Conclusions
The guideline update reaffirms standard care practices for post-cardiac arrest patients: targeting MAP ≥65 mmHg and normal oxygenation. Active fever prevention continues to be recommended.
ESICM provided specific guidance on neuroprognostication, while AHA offered a list of prognostic factors.
A new soft suggestion to consider whole body CT on most post-arrest patients would represent a significant change to usual care.
Left-heart catheterization should be performed emergently for patients with ST-elevation MI or catastrophic sequelae of occlusive myocardial infarction (e.g., cardiogenic shock, ventricular arrhythmias), even if comatose. Others should undergo routine coronary angiography before discharge if ischemic disease is suspected as a contributor to the arrest.
Always helpful