Cardiopulmonary Resuscitation (CPR) is a life-saving technique designed to restore breathing and circulation in a person whose heart has stopped. This modern, unified sequence of actions is the culmination of centuries of experimentation and distinct scientific breakthroughs made by several pioneers in the mid-20th century. Tracing the history of CPR reveals a long struggle to find an effective method for reviving the deceased, culminating in the standardized process used globally today.
Early Attempts at Resuscitation
Long before the modern era, attempts to revive unresponsive individuals relied on methods that were largely ineffective or bizarre. Early techniques, some dating back to the 18th century, included practices like blowing smoke into the rectum or using fireplace bellows to force air into the lungs. These methods were rooted in superstition or flawed physiological understanding, leading to minimal success.
In the 19th and early 20th centuries, manual manipulation techniques became the common practice for artificial respiration. The Silvester method (1858) involved laying the victim on their back and using the rescuer’s arms to alternately pull the victim’s arms above their head and press them against the chest. The Holger Nielsen technique (1930s) involved placing the victim on their stomach and using back pressure and arm lifting for ventilation. While these were organized efforts to restore breathing, they moved only a small volume of air, proving inadequate for proper oxygenation.
The Standardizing of Airway and Breathing
The first significant step toward modern resuscitation focused on establishing an effective method for ventilation, known today as the Airway and Breathing components. Anesthesiologist James Elam provided scientific proof that a rescuer’s exhaled air was sufficient to provide adequate oxygenation for a non-breathing person. This finding directly challenged the established, ineffective manual methods.
Elam’s work was validated and expanded by Peter Safar, also an anesthesiologist, who researched airway management and rescue breathing. Safar demonstrated that simply tilting the head back and lifting the chin could open a blocked airway. In 1958, Safar and Elam published research showing mouth-to-mouth resuscitation was superior to all existing manual methods for proper ventilation. Their evidence established the scientific foundation for rescue breathing, replacing the cumbersome arm-lift and chest-pressure techniques. This work led to the creation of the first CPR training manikin, Resusci-Anne, to teach the technique to the public.
Discovering Closed-Chest Compressions
Concurrently with the breakthroughs in ventilation, a separate team focused on the problem of circulation. This work began at Johns Hopkins University, where electrical engineer William Kouwenhoven led a team including graduate student Guy Knickerbocker and cardiac surgeon James Jude. They were researching defibrillation for power company workers who suffered electric shocks, aiming to create a non-invasive device to restart the heart.
During experiments with a closed-chest defibrillator prototype in 1958, Knickerbocker observed that pressing the electrodes firmly onto a dog’s chest caused a temporary rise in blood pressure. Jude recognized this phenomenon as an external form of cardiac massage. The team demonstrated that rhythmic, forceful pressure on the sternum could circulate about 40% of normal cardiac output, sustaining vital organs. This discovery offered a non-surgical alternative to the highly invasive open-chest cardiac massage previously required to restart a stopped heart.
Integrating the Components into Modern CPR
The final step was the practical integration of the two separate discoveries: Safar and Elam’s effective rescue breathing and Kouwenhoven, Jude, and Knickerbocker’s external chest compressions. In 1960, these two components were formally combined into the single, sequential procedure known as Cardiopulmonary Resuscitation. This synthesis marked the birth of modern CPR, providing a complete solution for both oxygenation and circulation.
The American Heart Association (AHA) and the American Red Cross recognized the potential of the combined technique. They began standardization, leading to the first formal CPR guidelines in the early 1960s. This standardization was instrumental in transitioning CPR from a specialized medical procedure to a skill taught to the general public. The dissemination of training, often using the Resusci-Anne manikin, transformed CPR into a widespread public health initiative capable of saving lives outside of hospital settings.