Stroke: Why Time Lost Is Brain Lost

Every minute is critical after a stroke—do you know the early warning signs?

Doctors rush a patient to the ER in the critical time after a stroke. Time lost is brain lost when it comes to stroke.

Medically reviewed in January 2022

Every 40 seconds, someone in the United States has a stroke. Like heart attacks, strokes happen suddenly and can affect anyone. These so-called “brain attacks” occur when blood flow to the brain is interrupted by either a clot (ischemic stroke) or a ruptured blood vessel that bleeds into the brain (hemorrhagic stroke). 

When blood flow is cut off during a stroke, brain cells that rely on a constant supply of oxygen to control vital functions, like memory, speech and muscle movement, die. Once symptoms appear, it’s a race against the clock. In the critical time after a stroke, every minute that it goes untreated, the risk for lifelong disability or even death increases. 

The sooner someone who’s suffered a stroke gets to a hospital equipped with the resources and staff needed to provide state-of-the-art stroke care, the more likely they are to recover, according to Donald Frei, MD, a neurointerventional radiologist affiliated with Swedish Medical Center in Denver, Colorado. 

We spoke to Dr. Frei to learn more about the early warning signs of stroke and why timely treatment is so critical. 

Some research suggests that nearly 40 percent of Americans aren’t aware of all major stroke symptoms, which could delay treatment. How can people recognize when they or someone else is having a stroke? 
Dr. Frei: Some people could have a stroke and not realize it. But in many cases, someone who is having a stroke will have a sudden onset of symptoms, such as a unilateral loss of sensation or strength. So, they would have numbness or weakness in their face, arm or leg either on their left or right side—not both. They may be unable to speak or have slurred speech. They may also suddenly develop vision loss, dizziness or loss of balance and coordination. Any of these things could be among the signs or symptoms of a stroke. 

Do symptoms vary depending on the type of stroke? 
Dr. Frei: There are two general categories of stroke. Most, or 85 percent of all strokes, are ischemic. They occur when blood supply to the brain is blocked, usually from a blood clot. The other type of stroke is a hemorrhagic, which accounts for about 15 percent of all strokes. These strokes usually occur when a weak blood vessel ruptures and bleeds into the brain. The symptoms of hemorrhagic strokes are usually similar to an ischemic stroke, but they are often associated with severe headache as well. 

Could the symptoms of a stroke change over time or even seem to improve? 
Dr. Frei: Yes, they can. During a transient ischemic attack or TIA, blood flow to part of the brain is temporarily blocked. Symptoms of a TIA are like other stroke symptoms, but they can come and go and do not last as long. When you have those symptoms, you have no idea if they're going to go away or be permanent. You have to treat any acute onset of these symptoms as something that's serious and brain threatening. TIA is often a warning sign. If you've had a TIA, you're much more likely to have a stroke in the near future if you don't figure out the cause of those symptoms and correct it. 

What should people do if they suspect that they or someone else is having a stroke? 
Dr. Frei: Call 911 right away. A brain attack is the most time sensitive medical emergency there is. 

There is a saying, ‘Time lost is brain lost.’ Why is the timing of stroke treatment so critical? 
Dr. Frei: The brain is a very sensitive organ that does not tolerate lack of blood flow for very long. You need to act really fast to have the best chance for a good outcome. For example, during an ischemic stroke, when an artery to the brain is blocked, part of the brain is not getting blood flow. At some point, that entire area will be irreversibly damaged. Some published research suggests you can lose up to two million neurons [nerve cells] per minute. The faster you get treatment and get the artery open, the better your chances of having those symptoms resolve and returning back to an independent life. 

The treatment goal for hemorrhagic stroke is to understand what’s causing the bleeding and stop it. But how are ischemic strokes managed? 
Dr. Frei: The blood clot causing an ischemic stroke can be removed with intravenous clot-busting medicine, called tPA [tissue plasminogen activator]. It's basically a medicine that dissolves the clot. This protein involved in the breakdown of blood clots is in everyone’s body but intravenous tPA is a concentrated form. This medication needs to be given within four and a half hours of the beginning of symptoms of an ischemic stroke. But beyond this window of time, patients given tPA have a high likelihood of having a brain hemorrhage. 

If a large artery is blocked, you could get a different type of treatment, called thrombectomy. This is a procedure to mechanically remove a blood clot from inside an artery. A catheter is delivered through a femoral artery over the hip and steered up into the arteries in the neck that supply the brain. The clot is then suctioned or sucked out through the catheter. That could potentially be done up to 24 hours after the onset of symptoms. Some stroke patients may receive combined therapy or be treated with both medication and a mechanical thrombectomy. 

When received in a timely manner, how effective are existing stroke treatments? 
Dr. Frei: One of the important things to understand is that a lot of people think that there is no treatment for stroke. In fact, treatment for ischemic stroke is probably one of the most effective therapies in medicine. But it works best if you get to the hospital as quickly as possible with no delay. Getting to the right hospital with expertise in stroke care is also really important. 

An increasing number of hospitals across the United States, which meet certain standards of care, are certified as Comprehensive Stroke Centers or Primary Stroke Centers. What is the advantage for patients? 
Dr. Frei: Certified stroke centers have a whole team that is well-trained and practiced on treating acute stroke very quickly and safely. There are many primary stroke centers in the United States where they can give IV tPA. Comprehensive stroke centers can give IV tPA and mechanical thrombectomy but there are fewer of these centers around the country. The point is, if you have a dedicated stroke team that does this all the time, they do it very quickly. The ER team is fast to notify the stroke neurologist, the pharmacist also shows up right away. The time from arrival in the ER to treatment is superfast. 

At our hospital, the average time from arrival in the ER to IV tPA is 17 minutes. If you're in a hospital that's not certified—or even if you're just in a primary stroke center that doesn’t treat acute stroke as often—it’s going to be slower. The speed of treatment is faster in comprehensive centers that are certified and do it all the time. It’s important to identify the best option in your area and know where you need to go. 

How can swift treatment that’s measured in minutes—not hours—affect stroke patients’ long-term outlook?  
Dr. Frei: The faster you get treatment the more likely you are to live an independent life after having a stroke. The longer the delay—either you getting to the hospital or receiving treatment once you’re there—the higher your likelihood of death or being permanently disabled. 

Some studies have looked at this and they've found that for every 30-minute delay in ischemic stroke treatment, your chance of having a good recovery drops by 10 percent. Basically, an hour and a half delay could significantly lower your odds of remaining independent. 

Stroke has dropped from the third leading cause of death in the U.S. to the fifth. Is this due—at least in part—to progress that’s been made in stroke treatment and ensuring that patients receive timely care? 
Dr. Frei: Yes, I think that is reflective. The mortality rate has gone down, which is great. But it's important to remember that stroke is still the number one cause of adult disability. We've made some inroads, but we still have a long way to go. One of the challenges is that if you are having a stroke, you may not even know it. You may not be aware of the weaknesses on one side of your body. It's important that everybody knows the signs and symptoms of stroke. You may slump down at your desk and not have any idea what's really going on, but your coworker could notice that something is wrong and seek help. 

We talked about what happens in the critical time after a stroke. But what are the longer-term changes that people who’ve had a stroke need to make? 
Dr. Frei: The best treatment for stroke is prevention or having a healthy lifestyle. Smoking, poorly controlled high blood pressure, high cholesterol and diabetes are among the risk factors for having an ischemic stroke. If you can manage those issues, you will definitely decrease your risk of having another stroke in the future.

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