Why Time Is Critical During Sudden Cardiac Arrest

Imagine a seemingly healthy adult collapsing suddenly in a grocery store or a young athlete losing consciousness in the middle of a game. In an instant, their lives — and their loved ones — change forever.

Each October, organizations across the country recognize Sudden Cardiac Arrest Awareness Month to highlight this leading cause of death and remind communities how vital immediate action is. Behind every sudden cardiac arrest (SCA) statistic is a family member, teammate, or neighbor whose life could be saved if someone nearby acts in those first few minutes.

How you react in the early minutes of SCA can save a life

Sudden cardiac arrest is a life-threatening condition in which the normal electrical impulses in the heart cause it to beat too quickly, inefficiently, or in an unsynchronized manner. These abnormal heart rhythms are known as pulseless ventricular tachycardia and ventricular fibrillation. During SCA, blood flow to the brain and vital organs abruptly stops, along with the oxygen it carries. In turn, brain cell death begins within minutes due to lack of oxygen.

While cardiopulmonary resuscitation (CPR) alone won’t restart the heart in cases of sudden cardiac arrest, it plays a crucial role in preserving brain and body function. When performed correctly, chest compressions keep oxygen-rich blood circulating to the heart muscle and brain until an electric shock from an automated external defibrillator (AED) can restore a normal rhythm.

Research shows that for every minute without defibrillation, a person’s chances of survival decrease by 7% to 10%. Therefore, immediate CPR and early AED use are the most important factors in keeping a person alive during sudden cardiac arrest, buying precious time and helping prevent catastrophic damage to the brain and other vital organs while waiting for emergency services.

Why simply waiting for EMS can reduce odds of survival

When someone collapses from sudden cardiac arrest, calling 911 is essential to get professional help in route as quickly as possible. But waiting passively for them to arrive isn’t enough.

The Sudden Cardiac Arrest Foundation reports:

• There are approximately 350,000 out-of-hospital cardiac arrests (OHCA) each year in the United States.
• The majority of adult OHCA events occur at home or in a residence (71%), followed by public settings (12% to 15%).
• Approximately 41% of OHCAs receive bystander CPR.
• Survival rates to hospital discharge for adults is only about 10%, which has remained virtually unchanged for the past three decades.

These statistics underscore a stark truth: Every minute counts.

Even when 911 is called right away, real-world challenges can delay care. Average emergency medical services response times often exceed the critical window for brain survival. Common barriers include:

• Rural areas. Long travel distances, remote locations, and difficult-to-access roads.
• Urban centers. Heavy traffic, limited street access, and high-rise buildings with multiple floors.
• Suburban neighborhoods. Locked community gates or confusing layouts can hinder quick access.
• Public events. Dense crowds and uncertainty over who should take charge during an emergency.
• Severe weather. Heavy rain, snow, or flooding can prolong or re-route EMS.

Even under ideal conditions, professional first responders may take several minutes to reach the scene — and with sudden cardiac arrest, those minutes mean everything. By the time help arrives, the difference between life and death (or between full recovery and permanent brain injury) often depends on whether someone nearby recognized the signs of cardiac arrest and chose to act.

Your actions in those first few minutes can directly determine a person’s likelihood of survival and quality of life afterward.

The chain of survival: Where bystanders fit in

The chain of survival lays out the best approach to cardiac arrest care. The adult chain of survival links are as follows:

1. Early recognition of cardiac arrest and prompt activation of EMS.
2. Immediate high-quality CPR beginning with chest compressions.
3. Early defibrillation with an AED (when indicated).
4. Effective advanced life support treatment.
5. Effective post-cardiac arrest care at a hospital.
6. Recovery.

The greatest chance of survival exists when all six interdependent links are strong. But the first three links depend almost entirely on the actions of bystanders. Recognizing signs of cardiac arrest, calling for help, and starting CPR are often the deciding factors in whether a person survives sudden cardiac arrest.

Unfortunately, these first links break down for a variety of reasons. Some bystanders hesitate to act because they’re worried they might do something wrong or hurt the person. Others aren’t trained in CPR or don’t know where to find the nearest AED, especially in large public places or workplaces where devices may be locked away or poorly labeled.

Every moment that passes without CPR or defibrillation lowers the person’s chance of survival, which is why CPR training, awareness, and accessible AEDs are vital in every community and workplace.

Every second counts: Be the link that saves a life

Whether it happens during physical activity, at work, or in your own home, sudden cardiac arrest is a medical emergency where minutes matter. Every second without oxygen or blood flow increases the risk of permanent brain damage or death.

You don’t need to be a healthcare provider to make a significant impact. You just need to be willing to act. If you witness someone collapse and they’re not breathing normally:

1. Call 911. Put your phone on speaker and follow the dispatcher’s instructions.
2. Start CPR. If you aren’t CPR certified, start hands-only CPR by pushing hard and fast in the center of the chest.
3. Use an AED as soon as it’s available. The device will guide you through each step, including AED pad placement and advising if a shock is needed.

Make time this month to refresh your lifesaving skills and encourage your friends, family, and coworkers to do the same. Every trained bystander strengthens your community, potentially giving someone their best chance at life, recovery, and a future with their loved ones.

To get CPR, AED, and First Aid certified, find a class near you with an authorized HSI Instructor. Or consider becoming an HSI Instructor to play an active role in making your workplace and community safer!