CPR is an emergency procedure combining manual chest compressions with artificial ventilation (rescue breathing) to sustain life. This technique is applied when a person’s breathing or heart has stopped, such as during cardiac arrest. CPR works by manually circulating oxygenated blood to the brain and other vital organs until definitive medical treatment can restore normal heart rhythm and breathing. The modern, standardized method of CPR emerged from distinct scientific breakthroughs in the mid-20th century, culminating centuries of attempts to revive the seemingly deceased.
Precursors to Modern Resuscitation
Long before the scientific understanding of the circulatory and respiratory systems, people attempted to revive others using speculative and often bizarre methods. The earliest organized efforts appeared in the 18th century, particularly concerning drowning victims, leading to the establishment of the Society for the Recovery of Drowned Persons in Amsterdam in 1767.
Early techniques included rolling the victim over barrels to expel water or applying flagellation to stimulate the body. One widely recommended, though ineffective, method was “rectal fumigation,” which involved blowing tobacco smoke into the rectum using a bellows, believed to warm the body and stimulate life. Mouth-to-mouth ventilation was documented as early as 1732 by Scottish surgeon William Tossach, but it fell out of favor for a time.
Methods like the Marshall Hall method and the Silvester method, which relied on manipulating the victim’s arms and chest to create air movement, gained popularity in the 19th century. These manual techniques were largely ineffective at providing adequate ventilation or circulation, demonstrating the primitive state of resuscitation science until the mid-20th century.
The Integration of Ventilation and External Compression
The development of modern CPR required two separate, evidence-based discoveries concerning ventilation and circulation, which occurred almost simultaneously in the 1950s. The first component, effective artificial ventilation, was championed by Dr. James Elam and Dr. Peter Safar. In 1954, Elam demonstrated that a rescuer’s exhaled air contained sufficient oxygen to maintain adequate levels in a non-breathing patient.
Safar and Elam collaborated to prove the superiority of the mouth-to-mouth method over ineffective manual techniques. Their work established the first two steps of the future resuscitation protocol: “A” for Airway (often achieved with the head-tilt maneuver) and “B” for Breathing (using mouth-to-mouth ventilation). The efficacy of this rescue breathing technique was formally established and promoted to the medical community by 1957.
The second component—the circulation aspect—was discovered at Johns Hopkins University by Dr. William Kouwenhoven, Dr. James Jude, and Dr. Guy Knickerbocker. While working on external defibrillation, Knickerbocker observed that applying pressure to a dog’s chest briefly elevated its blood pressure. The team quickly realized that forceful, rhythmic pressure on the chest could artificially pump blood through the body.
This technique, known as closed-chest cardiac massage or external chest compression, provided a non-invasive way to maintain blood flow to the brain and heart. Their landmark paper in the Journal of the American Medical Association in 1960 affirmed that chest compressions could sustain life. Cardiopulmonary Resuscitation was formally developed around 1960 when these two distinct techniques—rescue breathing and chest compressions—were combined into a unified protocol.
Codification and Global Adoption
With the scientific foundation of combined ventilation and circulation established, the next phase involved standardizing the procedure and making it accessible to the public. The American Heart Association (AHA) formally recognized and endorsed the new combined technique in 1963, a significant step toward moving the procedure out of the hospital and into the hands of emergency responders.
A pivotal moment occurred in 1966 when the National Research Council of the National Academy of Sciences convened a conference on Cardiopulmonary Resuscitation. The conference addressed requests for standardized training and performance criteria from organizations like the American Red Cross, and the resulting report advocated for widespread training.
The standardization process transformed CPR from a clinical procedure used only by medical professionals into a public health skill. Organizations like the AHA and the Red Cross developed comprehensive training programs based on this consensus, creating curricula and training films that ensured the unified protocol could be taught consistently worldwide.