Cardiac arrest is still treated with medieval methods. And, not surprisingly, with low survival. The best we have to offer is an orderly’s rhythmical crushing of ribs and chest, with a few squirts of adrenaline thrown in for good measure. Surely, in the 21st century there must be a better way?
I believe in ECMO. ECMO can treat anything. Two quite large studies on Extracorporeal Membrane Oxygenation used to treat cardiac arrest show promising results for ECMO CPR vs conventional CPR. Both studies were done on witnessed in-hospital cardiac arrests without ROSC after 10 mins. V-A ECMO was initiated through canulation of the femoral artery and vein. One of the studies is retrospective, the other prospective. Both have sampled material over several years. Dr. Chen and Dr. Shin have conducted the studies in Taiwan and South Korea, respectively.
Two things to notice in both studies:
- The consistent extremely quick response time of the ECMO CPR teams, day and night. 5-10 min in day time, 15-30 min at night time. It’s hard to imagine a set-up that would give similar response times from such highly specialized teams in hospitals in the countries I have worked.
- The rather high number of cardiac arrests in these hospitals. I hope they are BIG hospitals.
Both studies have strived to balance the patients in the two arms, E-CPR and C-CPR. Chen’s study looked at survival to discharge and Shin’s study looked at survival to discharge with minimal neurological impairment. There has also been a follow-up after six months. In both studies, E-CPR gave approximately a 20% higher survival compared to conventional CPR. Read that again: 20% higher survival. It makes the discussions around adrenaline or no adrenaline, and 15:2 or 30:2 seem pretty meaningless.
So what does ECMO do? It buys time. You don’t get ROSC, you get ROC.
- Time for the medical team: While we’re pumping manually on the patient’s chest, the patient can’t really be moved, and time is running out quickly. With ECMO you buy time to get the patient to the ICU and get a more qualified evaluation of the patient and the deciding on the choice of continued treatment.
- Time for the patient: You will often see acute, severe heart failure as you get ROSC after cardiac arrest. So severe that the patient can’t sustain circulation and life. The heart’s function will often spontaneously improve within the next couple of days. But, obviously, the patient needs adequate circulation in that waiting period.
Chen’s study published in Lancet 2008:
Cardiopulmonary resuscitation with assisted extracorporeal life-support versus conventional cardiopulmonary resuscitation in adults with in-hospital cardiac arrest:
an observational study and propensity analysis
Shin’s study published in Critical Care 2011:
Extracorporeal cardiopulmonary resuscitation in patients with inhospital cardiac arrest: A comparison with conventional cardiopulmonary resuscitation
This post was originally published in Norwegian, 10. sept 2011: