The Engineer Who Could
By Janet Farrar Worthington
Jolting a dying heart back to life became an actuality thanks to a Hopkins dean who made medicine his second career.
n a century marked by unprecedented medical accomplishments, it is perhaps the most staggering achievement of all: The discovery that a stopped heart--once the definition of death--can be made to beat again.
That a person who has, technically, gone over the brink into lifelessness can be reclaimed through mouth-to-mouth breathing and chest compressions, and a last-ditch weapon--the amazing machine known as the defibrillator, which jump-starts a twitching heart back into normal rhythm.
And yet 60 years ago, there was no remedy for ventricular fibrillation (VF), an irregular rhythm in which the heart, unable to produce organized electrical activity--and thus pump blood--suddenly becomes a disoriented, quivering bag of Jell-O. The fatal condition, physicians knew, could be brought on by a massive coronary artery blockage and by the anesthesia then used in surgery. It could also be triggered by an electric shock as witnessed by the bleak fates of many power utility linemen of the 1920s and '30s who died on the job of VF. The electric companies themselves were the most invested promotors of research that might shed light on how to rectify such cases of sudden, abnormal heartbeat.
Enter Hopkins, one of a handful of sites around the country selected in 1925 by the power company Consolidated Edison of New York to study the ravages of electric shock. Amazingly, the investigation here, under the general direction of Hopkins physician William Henry Howell, was spearheaded by someone with no medical background at all-- William B. Kouwenhoven, a professor of electrical engineering known for his creative mind. The pipe-smoking, contemplative professor was a brilliant choice: Over the next five decades, during which he retired from the deanship of Hopkins' Whiting School of Engineering and took on a second career as a lecturer in surgery, Kouwenhoven and his medical colleagues tirelessly revolutionized cardiovascular resuscitation, all the while proving just how much a wildly disparate interdisciplinary team can do.
Ravages of Electric Shock
he engineer's experiments began with rats. Along with Hopkins neurologist Orthello Langworthy, M.D., Kouwenhoven observed the effects of DC and AC shock on the heart. In humans, they noted that low-voltage shocks cause VF; higher-voltage shocks cause the lungs to shut down completely. By 1933, they had stumbled across an amazing finding: By administering still another surge of electricity, called a countershock, they were able to restore sinus rhythm and normal contraction, making a dog's fibrillating heart beat normally again--a process called defibrillation. Confirming the results of an all-but-forgotten paper that had appeared in an 1889 medical jour-nal, Kouwenhoven's team stirred scientists elsewhere, including those at Case Western Reserve, who used the technique on patients who had slipped into VF during surgery. In 1947, Case Western's Claude Beck, a 1921 graduate of the School of Medicine, was the first to place electrodes directly on the heart of a patient suffering VF during surgery.
At Hopkins, Kouwenhoven's studies inspired Division of Anesthesiology researchers James Elam and Peter Safir, who would go on in the 1940s to perfect the emergency mouth-to-mouth method of lung ventilation, crucial for oxygenating the blood when the heart stops. But it would take a well-rounded team of investigators, including Kouwenhoven, James Jude, M.D., a protÈgÈ of cardiovascular surgeon Alfred Blalock, M.D., G. Guy Knickerbocker, a young engineer, and the cardiovascular physiologist William Milnor, M.D., to develop the life-jolting machine that eventually would save the lives of thousands of people.
Life Sparing Machine
ouwenhoven and Milnor began working on a closed-chest defibrillator in 1950, testing various electrical currents, pulses and electrodes to find the ideal combination that would jar the heart back to normal cadence. Chief of surgery Alfred Blalock was at first skeptical of the work, but he agreed to provide laboratory space and support services for Kouwenhoven's growing team.
The investigators watched the effect of electrodes on opposite sides of the chest, noting that a brief AC current of 20 amperes would jolt the erratically beating heart back into rhythm. Then, another surgeon, Samuel Talbot, who was studying heart arrhythmias in dogs, asked the team to incorporate their defibrillator experiments with his research. To their surprise, Kouwenhoven and Milnor found that the current actually flowed best vertically instead of horizontally through a dog's heart, and they were able to reduce the intensity of the shock by 50 percent. After hundreds of laboratory tests, they developed a prototype machine to do the job on humans.
The novel contraption was unwieldy--a hefty 200 pounds mounted on a wheeled cart--and delivered AC current via two main electrodes, one placed over the suprasternal notch, the other over the apex of the heart. During the initial experiments on dogs, Knickerbocker noticed a small rise in blood pressure when the electrodes were pressed into position?even before any current passed through them. Was it possible, he speculated, that pressing rhythmically on the chest could cause the blood to circulate? From that observation, Knickerbocker and Kouwenhoven led the way to the team's third major discovery: cardiac massage, the technique that would become key to cardiopulmonary resuscitation.
To the Rescue
inally, in 1957, for the first time, the defibrillator saved the life of a patient suffering VF in a Hopkins operating room. Three years later came the event that would set the course for the principal use of the remarkable machine.
A patient arrived in the emergency room at 2 a.m. complaining of indigestion, and in the midst of undressing for his exam, suddenly collapsed with ventricular fibrillation. The admitting resident, Gottleib Friesinger, M.D., (today a Vanderbilt University cardiologist and a Johns Hopkins University board member) was familiar with the promising device located in a laboratory on the Hospital's 11th floor. He had even assisted in some of the research. As the intern on call thumped the patient's chest, Friesinger rushed to the laboratory, persuaded a security officer to let him in and then wheeled the contraption to the ER. On the second shock, Friesinger revived the dying 42-year-old patient. The man had suffered an anterior myocardial infarction and lived for 18 more years. It was the world's first emergency defibrillation for cardiac arrest. "He was quite a dramatic Saturday morning Grand Rounds presentation," Friesinger recalls.
With this success, electric companies urged further experiments, encouraging the development of a closed-chest defibrillator that would be portable and also inexpensive. The innovative Kouwenhoven went on to develop that smaller model--svelte in comparison at only 45 pounds, 20 inches long, 15 inches high and seven and a half inches wide, and workable either by a small battery or AC current.
For his remarkable contributions to cardiology, in 1969 Kouwenhoven received the first-ever honorary Doctor of Medicine degree from Hopkins. Four years later, his tremendous trio of contributions--confirmation of the effects of countershock, the refinement of open- and closed-chest defibrillators, and the development of external cardiac massage--earned him this country's most prestigious scientific honor: The Albert and Mary Lasker Foundation Award. *
Janet Farrar Worthington last wrote for HMN on prostate cancer.