The Evolution of CPR

by Dr. Mary Williams, R.N. D.C.

Cardiopulmonary resuscitation, more commonly known as CPR, is a procedure that is used in efforts to save a person's life. CPR is a combination of chest compressions and rescue breathing. It performed when a person has stopped breathing or when their heart has stopped beating. This usually occurs when a person has had a heart attack, has come close to drowning, or has been shocked by electricity. The use of CPR can double the chance of survival in these instances. Over the years, there have been many changes in the CPR procedure.

Cardiopulmonary resuscitation did not simply begin all at once. It took many years for the process to be pieced together; however, the act of mouth-to-mouth resuscitation alone became the official response to those in drowning accidents in the year 1740, when the act was recommended by the Paris Academy of Sciences. The original recommendation was very simple, although in 1767, the Society for Recovery of Drowned Persons was formed and led to a very organized manner of responding to near death emergencies. The recommendations of the society included positioning the head below the feet to attempt to remove water that was swallowed or breathed in, warning the victim, pushing on the stomach, tickling the throat, bloodletting, inserting air into the mouth orally or through use of a bellow and stimulating the drowning victim rectally or orally with tobacco smoke through the use of a bellow. A bellow was a hand-held device with a valve and a nozzle that was used to create a blast of air for use with a fireplace. The nozzle was often inserted into the mouth in lieu of using a mouth-to-mouth technique. After only four short years, these methods were reported to have saved 150 lives. After this report, people became interested and amazed that the act of resuscitation could essentially bring back the dead.

Several years later, in 1891, Dr. Friedrich Maass was the first to perform documented chest compressions on humans. Then, a few years later in 1903, a man by the name of Dr. George Crile was the first to report that chest compressions outside of the body were truly successful in resuscitating humans. After many years of using mouth-to-mouth resuscitation alone, James Elam was the first person to actually prove that this method was capable of providing an adequate amount of oxygen to sustain life. The act of combining the two techniques in efforts to save human lives was not done until many years later in 1960. This combination of mouth-to-mouth breathing and external chest compressions was developed and the American Heart Association quickly introduced the technique to physicians and began to inform and train the public on the use of CPR.

While quite a few of the techniques used in resuscitation methods in the 1700s remained, with the evolution of medical information and technology, it became clear that a few of these methods were not helpful. The acts of tickling the throat, bloodletting, and attempting to "shock" a victim with tobacco smoke did not prove to be helpful after proper research, and in many cases were actually harmful. As a result, these practices were dropped and not incorporated into modern day resuscitation methods. The use of bellows as a means of forcing air into the lungs was also discontinued in 1829 after a man by the name of Leroy d'Etiolles proved, through the use of animals, that inserting too much air into the lungs could cause death. The techniques that did prove to be helpful during resuscitation attempts, however, were organized into an easy to remember A-B-C method. The ABCs of CPR stand for Airway, Breathing and Circulation. First, responders were to tilt the victim's head back to open the airway and then look, listen and feel to determine if the victim was breathing. If the victim was no longer breathing, they would move to the breathing portion of the ABCs. Responders would pinch the victim's nose and give full breaths into the person's mouth. Lastly, they were instructed to begin chest compressions to provide circulation if no pulse was detected. If both rescue breathing and chest compressions and rescue breathing were to be performed simultaneously, the correct method was 15 chest compressions for every 2 rescue breaths. This practice was taught as the proper way to perform CPR on an unresponsive person until professionals could arrive and provide further care for nearly 40 years.

In 2010, the ABC method of CPR was changed by the American Heart Association after realizing that the act of rescue breathing, along with looking, listening and feeling, was drastically delaying the time it takes to begin chest compressions to keep blood flowing. With this realization, the American Heart Association rearranged the ABCs of CPR to CAB (Circulation, Airway, Breathing). Other changes also included forgoing the looking, listening and feeling step altogether and quickly beginning chest compressions on anyone (excluding newborns) who is unresponsive or not breathing properly. The American Heart Association also currently recommends that rescuers provide chest compressions at the rate of 100 compressions a minute, which is significantly faster than the 1960 recommendation of 60 compressions a minute.

Throughout history, there have been numerous changes to the ways that resuscitation methods are performed and taught. The effectiveness of attempting resuscitation versus not attempting it at all has not changed, however. The use of CPR, or cardiopulmonary resuscitation, has saved the lives of countless people. Many of these people would have otherwise perished before emergency help could arrive and assist with medical devices such as defibrillators and oxygen tanks. As medical technology continually advances, there will surely be further improvements in the techniques and methods used during CPR for many years to come.