🩺 THIS WEEK IN EM
Stop Cooling Post-Arrest Patients to 33°C. TTM2 Changed Everything.
The TTM2 trial randomized 1,850 comatose survivors of out-of-hospital cardiac arrest at 61 ICUs across 14 countries to targeted hypothermia at 33°C versus targeted normothermia at ≤37.5°C with early treatment of fever. Primary outcome: all-cause mortality at 6 months.
Hypothermia at 33°C did not improve survival: 50% mortality in the hypothermia group versus 48% in the normothermia group. Functional neurologic outcome was also equivalent. Hypothermia caused more arrhythmias with hemodynamic compromise: 24% versus 16%.
This overturned about 15 years of post-arrest habit built on two smaller 2002 trials. The physiology for cooling always sounded smart. The large trial data just never backed it up. Fever is bad. Prevent it aggressively. But actively dragging people to 33°C is not buying you better outcomes and may be buying you complications.
Bottom line: Target normothermia (≤37.5°C) and aggressively treat fever after cardiac arrest. Routine cooling to 33°C is no longer supported.
Dankiewicz J, Cronberg T, Lilja G, et al. Hypothermia versus Normothermia after Out-of-Hospital Cardiac Arrest. N Engl J Med. 2021;384(24):2283-2294.
No Immediate Angiography After Arrest Without ST Elevation. Two Trials Agree.
Two key trials — COACT and TOMAHAWK — asked whether survivors of out-of-hospital cardiac arrest without ST elevation should go straight to the cath lab. The answer was no.
TOMAHAWK randomized 554 patients and found 30-day mortality of 54.0% with immediate angiography versus 46.0% with delayed/selective angiography — numerically worse with the immediate strategy, though not statistically significant. COACT randomized 552 patients and found 90-day survival of 64.5% with immediate angiography versus 67.2% with delayed angiography. Again: no benefit.
That does not mean coronary disease is irrelevant after arrest. It means “post-ROSC with no STE” is not, by itself, a cath-lab activation criterion. Stabilize the patient. Manage the brain, the hemodynamics, the ventilator, the temperature. Then do the angiogram in a planned way.
Bottom line: In OHCA survivors without ST elevation, routine immediate coronary angiography does not improve survival or neurologic outcomes. Stabilize first.
Desch S, Freund A, Akin I, et al. Angiography after Out-of-Hospital Cardiac Arrest without ST-Segment Elevation. N Engl J Med. 2021;385(27):2544-2553.
ECMO for Cardiogenic Shock: Big Machines, Still Complicated Evidence.
The ECMO-CS pilot trial randomized 117 patients with acute cardiogenic shock to early VA-ECMO versus standard care. The primary composite outcome was numerically lower with ECMO, but not significantly so: 37% versus 54%. Thirty-day mortality was essentially the same: 41% versus 40%.
That matters because ECMO has a way of becoming the answer whenever the patient looks sick enough and the center is fancy enough. The problem is that rescue technology and mortality benefit are not the same thing.
And the broader story got clearer, not fuzzier: the larger ECLS-SHOCK trial also failed to show routine mortality benefit from ECMO in AMI-related cardiogenic shock, while reinforcing that complication burden is real. So the accumulating signal is pretty consistent — ECMO is a selective rescue therapy for carefully chosen patients at experienced centers, not a default escalation move because everyone in the room is getting nervous.
Bottom line: VA-ECMO has not shown clear routine mortality benefit in cardiogenic shock RCTs. Use it selectively, not reflexively.
Ostadal P, Rokyta R, Kruger A, et al. Extracorporeal Membrane Oxygenation in the Therapy of Cardiogenic Shock (ECMO-CS): A Randomized Clinical Trial. Circulation. 2023;147(6):454-464.
📚 STILL CHANGING PRACTICE
If you haven’t internalized this yet, now’s the time.
COACT: The Guideline-Changer People Still Ignore.
COACT deserves its own section because it directly changed practice and still gets ignored in some places. Lemkes and colleagues randomized 552 patients resuscitated from OHCA without ST elevation to immediate coronary angiography (within 2 hours) versus delayed angiography after neurologic recovery or ICU stabilization.
Ninety-day survival: 64.5% immediate versus 67.2% delayed. Neurologic outcomes were also equivalent. Immediate angiography added more procedure urgency without adding patient benefit.
The important nuance: this is not an anti-cardiology trial. Coronary disease is still common in these patients. The question is when to intervene, not whether coronary disease exists. The old “they arrested, so cath now” reflex is not evidence-based when the post-ROSC ECG lacks ST elevation.
Bottom line: For OHCA without ST elevation, immediate coronary angiography is no better than delayed. Stabilize first, cath later.
Lemkes JS, Janssens GN, van der Hoeven NW, et al. Coronary Angiography after Cardiac Arrest without ST-Segment Elevation. N Engl J Med. 2019;380(15):1397-1407.
Next Week 🔭
• Tranexamic acid in prehospital trauma: The PATCH-Trauma results — not the story everyone expected
• Damage control resuscitation: What the PROPPR trial established about blood product ratios
• Massive transfusion protocols: What’s changed and what hasn’t
The Hallway Consult is built for EM clinicians who want the useful version of the literature. Forward it to a colleague if it helped.