When Seconds Matter

 

Figure 1. Rescuers practice administering chest compressions and using an Automated External Defibrillator (AED) to resuscitate a victim of sudden cardiac arrest until help arrives.

 

The piercing sound of a glass coffee table shattering abruptly wakes her from a deep sleep. What started out as a regularly scheduled early morning gym session has now become a life threatening emergency when an otherwise healthy husband and father of two went into sudden cardiac arrest. Luckily, the loud crash and the sound of keys bouncing off the tile floor woke his wife who quickly ran downstairs to assess the situation. After finding him unresponsive, she calls 911 and immediately begins administering hands-only Cardiopulmonary Resuscitation (CPR). Although she is experiencing an extreme amount of stress, she remembers the very basics of her CPR training which she volunteered to take on a whim six months prior. She rolls him onto his back and, kneeling at his shoulders, begins pushing hard and fast—she mimics the “Stayin’ Alive” song beat which she recalls as the target rate for chest compressions.

 

From the second our patient crashes down to the floor, an internal metabolic crisis begins to unfold. Years of difficult-to-recognize plaque build-up has accumulated in his blood vessels, particularly in the arteries that feed oxygenated blood to his heart. These arteries, known as the coronary arteries, have become almost entirely blocked. The situation hit a breaking point this morning when, unexpectedly, the inadequate blood supply to our patient’s heart, also known as ischemia, caused a drastic change in the electrical activity that facilitates its proper functioning. The heart, which normally contracts in a rhythmic, methodical way, has now started quivering uncontrollably1. This uncontrolled quivering has effectively eliminated the blood flow through all major organs. As the brain is reliant upon an uninterrupted supply of oxygenated blood, he has quickly gone unconscious and fallen to the ground.

Figure 2. In a common arrhythmia called ventricular fibrillation, the ventricles of the heart begin chaotically depolarizing without functional ventricular contraction1. This condition produces a characteristic pattern on a 12-lead EKG as shown in the lower strip. A normal sinus rhythm is shown above it for comparison.

 

This situation is surprisingly common. According to a statistical update by the American Heart Association published in 2018, roughly 350,000 adults in the United States experience an outside-of-hospital cardiac arrest (OHCA) each year. Of those adults, 45.7% are able to receive bystander CPR2.

Amazingly, if a person experiencing OHCA is lucky enough to receive bystander CPR until professional help arrives, their chances of survival have been found to nearly triple. This drastic revelation in the effectiveness and importance of immediate bystander CPR is only dwarfed by one final statistic. That is, in nearly 70% of these OHCA cases, the incident in question will occur within the patient’s own home2. In other words, it is likely the patient’s closest friends and family members who will be responsible for dealing with the initial situation and ensuring that they have the best chance for survival.

Luckily for our patient, the time for which he has been in cardiac arrest without any external chest compressions, often referred to as “no-flow time” in the medical field, has been less than about 45 seconds thanks to his quick-thinking wife. As the ambulance crew rushes to their location, she has already begun addressing his lack of blood circulation by giving chest compressions and ultimately improving end-organ perfusion. Each compression she gives provides passive oxygenation which allows his cells to keep receiving oxygen and removing waste products. As our ambulance crew arrives just six minutes after the initial dispatch, they take over compressions and begin building off her immediate interventions to ensure he has the best chance to restore spontaneous circulation and be stabilized in a hospital.

 

Figure 3. Students in a CPR certification course take a knee and learn proper technique for providing chest compressions.

 

Now that we have explored the impact that bystander CPR can make, how can we actually get access to the training? Campus organizations like Alpha Epsilon Delta offer certification classes several times throughout the year. For off-campus resources, the American Heart Association’s website is one of the easiest and most convenient ways to locate and register for a certification class. Another major organization that offers convenient schedules and flexible training platforms is the American Red Cross. With an easy to navigate website, those interested in learning CPR can search for classes by location, date, type of class, or even sign up for an online based curriculum.

For those of us who want to learn the techniques but can’t commit the time or financial resources, there is free, non-certification based training available in several different formats. One of the greatest options is to locate a Hands-Only CPR event, several of which occur throughout the year in various locations around San Diego county and even on UC San Diego’s main campus. If that is still too much of a hassle, then the American Red Cross has built an easy-to-navigate section right into their main website that contains simple CPR instructions that anybody can access. With a few hours spent on learning these techniques, you can be the difference when seconds matter.

 

References

 

  1. Schoen JF, Mitchell RN. 2015. The heart, p 550-552. In Kumar V, Abbas AK, Aster JC, Robbins and cotran pathologic basis of disease, 9th ed. Elsevier Saunders, Philadelphia, PA.

 

  1. Benjamin et al. 2018. Heart disease and stroke statistics – 2018 update. Circulation 137:e356-e357.