By Jennifer Latson

When someone’s heart stops beating, acting quickly can mean the difference between life and death. More than 350,000 cardiac arrests occur outside of hospitals each year, according to the American Heart Association, and 90 percent of those sudden cardiac arrests prove fatal. But they don’t have to be. Immediate CPR, or cardiopulmonary resuscitation, and the use of an AED, or automated external defibrillator, can double or even triple the chances of survival — as they did for Buffalo Bills safety Damar Hamlin after he went into cardiac arrest during a game on Jan. 2. And they’re not as hard to do as many of us fear.

“An AED is really simple to use. The ‘A’ stands for ‘automated,’ meaning the machine does all the work. You just turn it on and it walks you through the instructions,” says Ross Brown, MD, an interventional cardiologist with Memorial Hermann. “And it’s so important to use it quickly, because time is of the essence.”

During cardiac arrest, the blood stops circulating, depriving the brain of oxygen — and it begins to shut down fast, Dr. Brown explains. “It only takes it takes 10 or 15 seconds without blood flow to the brain before a person loses consciousness,” he says. “In four minutes or so, brain cells start dying; by five minutes, irreversible damage occurs. You have four to five minutes before there are big problems, and once you get to 10 minutes or so, the chances of survival are slim. But if you see someone collapse and you call 911, most of the time it takes more than five minutes before the ambulance gets there.”

So what should you do if you see someone collapse suddenly? First, move the person to the ground or a hard surface and vigorously shake them to see if they respond, Dr. Brown recommends. Then check to see if they’re breathing and if they have a pulse. “If not, CPR is indicated. Call 911, or ask someone else to call 911 and to find an AED. As soon as possible, start CPR,” he says.

Anyone can do “hands-only CPR,” pressing hard and fast in the center of the person’s chest, aiming for 100 compressions per minute, according to the American Heart Association. People who are trained in CPR can also give intermittent mouth-to-mouth breaths, but the chest compressions are even more essential, says Dr. Brown.

“The most important thing is to try to maintain circulation. The blood holds a fair amount of oxygen in the hemoglobin, so getting that where it needs to go is crucial,” he says.

You may not know what caused the person’s heart to stop, whether it was a blood clot, a blocked artery, a drug overdose or something else. But the cause doesn’t really matter in the moments after a cardiac arrest, Dr. Brown says — you just need to keep the blood circulating until the person can get medical attention. And an AED can restart a stopped heart.

“The device really walks you through everything,” he says. “Turn it on and it’ll probably start by saying ‘Call 911.’ Once you’ve done that, it’ll tell you to place the pads on the patient. They’re maybe the size of a hand and they’re each attached to a wire. There’s a picture on the pads that shows you exactly where to put them: one on the right side of the sternum and one on the patient’s left side. The electricity goes between the pads and through the heart. The device will say ‘analyzing rhythm,’ and it will decide if there’s a rhythm that warrants defibrillation. It will either say ‘shock advised’ or ‘no shock advised.’ If it’s advised, you just have to press the button to deliver the shock. Once it finishes, you start CPR again and repeat the process as needed. Hopefully, you’re only there for a few minutes before emergency services arrives.”

When Dr. Brown does presentations about CPR in the community, people often express concerns about harming the person they’re trying to help. “You need to do quality compressions, which takes some force. You want to compress the ribs enough to squeeze the heart, and that surprises people, how hard you have to press. They say, ‘What if I break a rib?’ Sometimes you do, but it’s better to have a broken rib than not have circulation,” he says.

Ideally, everyone would be trained in CPR, Dr. Brown adds. “It’s not that hard to learn, and classes are readily available through the American Heart Association and the Red Cross. You never know when it might be your turn to save a life, and you don’t want to be looking around for someone who’s trained when the clock is ticking.” 

But even if you’ve never taken a class, doing something is better than standing idly by after someone’s heart stops. Many 911 operators can talk you through basic CPR. And don’t worry about doing it wrong, says Dr. Brown. “Even if your chest compressions aren’t at 100 percent strength, you’re still providing some circulation, and that’s better than nothing. You can’t make the situation worse than it already is. The moment their heart stops, they’re gone, and you’re doing everything you can to bring them back.”

For more information, visit www.memorialhermann.org/services/conditions/sudden-cardiac-arrest.