As an emergency doctor, I know that it’s incredibly rare for standard resuscitation protocols including CPR to revive patients brought to the hospital in cardiac arrest. Even in that setting, with all the available staff, equipment and drugs, if patients have not been resuscitated successfully within 40 minutes from the moment they first collapsed, their chances of survival after that are essentially nil.
But patients with certain types of cardiac arrest who are treated with a new procedure, called ECPR, have a nearly 100 percent chance of being revived, with their brain function intact, if treatment is administered within 30 minutes of collapse. Even if the intervention is delivered after 40 minutes, there is still a 50 percent chance of revival. Survival rates after cardiac arrest have hardly improved in decades, so when I heard about these statistics from one program in Minnesota, I was very eager to visit it.
Here is what to know about ECPR and its availability.
ECPR involves a lot more expertise and technology.
CPR stands for cardiopulmonary resuscitation. When a person collapses and is found to have no pulse, bystanders carry out CPR by doing chest compressions while waiting for professional help to arrive. If an automated defibrillator is available, using it to shock the heart with electricity may force it to beat again. In the E.R., doctors will continue with chest compressions and administer other standard resuscitation measures. These can include inserting a breathing tube, administering medications and possibly shocking the patient again.
But now a small number of hospitals are trying a new approach. Patients who are in cardiac arrest — meaning they have no pulse and are not breathing — can be connected to an ECMO machine, which then takes over the work of their heart and lungs. When this high-tech treatment is used during cardiac arrest, the intervention is called ECPR.
ECPR by itself does not cure anything. But by providing fresh blood flow to the brain and other organs, it enables the body to rest while giving doctors time to fix the underlying problem, if it’s fixable. Patients whose hearts are in a rhythm conducive to being shocked with a defibrillator fare much better, because they usually have a treatable cause behind their cardiac arrest.
Timing is everything.
For ECPR to have a chance at saving a person’s life, it must be started soon after a person suffers cardiac arrest, to keep the brain well perfused with oxygen. The most common reason people still die eventually, even after getting the treatment, is that their brains fail to recover from the initial reduction in blood flow.
First, bystanders must recognize that a person lacks a pulse, call 911 and start chest compressions. Emergency first responders must assess the patient quickly and coordinate with doctors who have the expertise to perform the procedure. Then the patient has to be removed from the site of collapse and be transported to a facility that is immediately ready to perform ECPR.
To provide treatment more quickly, some places have tried to meet patients where they are and start ECPR there, on the scene, instead of first moving them to a medical facility. This approach has had mixed results so far, but doctors are still trying to figure out how to get to patients before they arrive at the hospital in order to shorten the time until treatment starts. The program in Minnesota is using a big truck outfitted like a mini-mobile-hospital; in the Netherlands, doctors are testing the use of helicopters to reach patients quickly.
Having an ECMO machine isn’t the same as having an ECPR program.
Because time plays such a crucial role in successful ECPR, it’s not enough simply to have an ECMO machine. A detailed, thought-out program must be in place that has factored in everything from geography to assorted logistical considerations. Different health systems must work together efficiently; specially trained doctors have to be available 24/7; transportation needs to be extremely fast; and specialized I.C.U. care must be provided once the patient is connected to the ECMO machine, because the first 48 hours after that can be particularly tricky. These challenges help explain why such programs are very limited in the United States; those that do exist have yet to see the same survival rates as the one in Minnesota.
Complications during ECPR are not uncommon.
ECPR is a highly specialized, complex procedure that most doctors do not know how to do. It can also create its own set of complications. (Standard CPR, which can break ribs and crush organs, comes with its own dangers.) The big cannulas that must be inserted into patients’ blood vessels and that run from the groins all the way up to the hearts can cause organs to be perforated or blood vessels to be ruptured, leading to catastrophic bleeding. Or the procedure may simply not succeed — after all, it’s being undertaken in high-pressure, time-sensitive situations amid ongoing chest compressions. After a patient is hooked up to the ECMO machine, a special catheter needs to be placed in the patient’s leg to maintain its blood flow, or it, too, can die. ECMO machines can cause clots, so a powerful blood thinner is used, which in turn can also cause life-threatening bleeding.
