Johns Hopkins Magazine -- April 2000
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APRIL 2000


You needn't be a doctor to save a life, thanks to William Kouwenhoven.
APRIL 2000
Pioneers of Discovery

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Simply CPR
By Louise Cavagnaro with Barbara J. Kiviat '01

Until just 50 years ago, cardiac arrest meant almost certain death. A doctor's only option was to open the chest and massage the heart with the fingers--a procedure that could restart an inert heart but could not stop ventricular fibrillation (chaotic spasms). Only about 29 percent of the people undergoing this procedure survived.

But that was before Hopkins electrical engineering professor and Engineering dean William Kouwenhoven tackled the problem.

Kouwenhoven, who began researching electricity's effect on the human body in 1928, noted that utility linesmen who received accidental shocks often died when their hearts were jolted into fibrillation. In 1933, he and a team of Hopkins physiologists confirmed that an electric countershock could restore a normal rhythm to a defibrillating heart. That led to the first use, in Cleveland in 1947, of an electric defibrillator on a human heart. The patient, a 14-year-old boy, made a full recovery.

But this first defibrillator was an internal device, which meant risky surgery. In the 1950s, Kouwenhoven and his colleagues proved that defibrillation could also work through a closed chest, and designed the first portable defibrillator. Doctors at Hopkins first successfully used the concept on a human subject in 1957. This device had its drawbacks, too: a heart attack victim who was not within a few minutes of a hospital had little chance for survival.

In 1958, Guy Knickerbocker, a colleague of Kouwenhoven's, noticed that placing defibrillator paddles on a dog's chest caused a rise in blood pressure. The two men and another colleague, James Jude, experimented with different hand positioning and rhythms, and found that through external massage they could restore 40 percent of the normal blood circulation; they could continue for more than 30 minutes.

From May 1959 to February 1960, 20 Hopkins patients in cardiac arrest were administered cardiopulmonary resuscitation (CPR). All 20 were resuscitated. With the advent of CPR, cardiac patients can now be kept alive with no medical equipment and little training.