Historical Essay: The Heimlich Maneuver

People often ask me, “How did you invent the Heimlich maneuver? Were you in a restaurant and saw someone choking? Did someone ask you to invent it? Or did it just come to you one day?”

One day in 1972 I was reading an article in the Sunday New York Times Magazine about accidental deaths. What caught my eye was that choking to death was number six on the list. Three thousand people a year died from choking in this country alone. This particularly piqued my interest because, in the 1950’s I had developed the Reversed Gastric Tube esophagus replacement operation and, through much of my career, had become involved in evaluating patients’ swallowing problems.

What was most striking was how choking usually occurred in the most ordinary circumstances. The object on which most people choked was a piece of food or, with children, a toy, a coin, or any small object they happened to put in their mouth. Yet you rarely heard of these deaths. Only when a prominent person died – such as Ethel Kennedy’s sister-in-law, Joan Skakel, who choked to death on a chunk of meat, did you read about it in the newspaper. Two music stars, band leader Tommy Dorsey and pop singer Mama Cass Elliot, lost their lives to choking. I later learned that Claudius I, Emperor of Rome, had also choked to death accidentally – not strangled by a rival, as is commonly believed.

As always, the first step was to research the subject in the medical journals. I discovered that since 1933, the American Red Cross had been teaching people to save choking persons by slapping them on the back. As I read further, I realized there was no scientific basis for that recommendation. In fact, all reports from 1854 (Gross SD: A Practical Treatise on Foreign Bodies in the Air-Passages. Philadelphia, Blanchard & Lea, 1854) to the present prove hitting a person on the back drives the object downward, lodging it more tightly in the airway. Choking persons, who can still breathe, even with a piece of food in their throat, often die when back slaps cork their airway.

Of particular interest to the ABEA is the remarkable study from the Chevalier Jackson Clinic. Beginning with a series of 612 cases in 1917, the Clinic recorded nearly 6,000 choking patient studies in 1973. The observations and cautionary comments by Chevalier Jackson and others are remarkably similar to each other as well as to the conclusions drawn by Gross. All of these authorities describe the dangers of backslaps, probing the pharynx with a finger, or turning the patient upside down.

In 1969, the journal Transactions of the American Broncho-Esophagological Association warned the Red Cross that back slaps were killing people. As a result, the Red Cross changed its policy. The 1970 Red Cross manual read: “Do not allow anyone to slap you on your back if you are choking and do not try to dislodge an object from another person’s throat by this means except as a last desperate effort to save his life.” Strangely, after the Heimlich Maneuver emerged, the Red Cross again reversed itself and began recommending back slaps before performing the Heimlich Maneuver! That surely did not justify the years of faulty advice.

As I approached the problem, I decided that since back slaps caused deaths by forcing the object back downward in the airway the answer lay in creating a flow of air upward out of the lungs, using the lungs like a pair of bellows. As a thoracic surgeon, I knew there is always a large amount of residual air in the lungs, even after breathing out. To work up enough force to expel the object, I would have to find a way to compress the lungs sufficiently to create a strong flow of air out of the mouth.

In 1973, I began researching the problem in my laboratory at Cincinnati’s Jewish Hospital. I used an endotracheal tube as the foreign body obstructing the airway. I blew up the balloon at the lower end of the tube and closed off the upper end of the tube to prevent the flow of air through it. I inserted the balloon into the airway of an anaesthetized beagle. The balloon thus acted like a foreign object, such as a piece of meat, obstructing the airway. If I could produce a large flow of air by compressing the lungs, the tube should move upward out of the airway.

I pressed repeatedly on the dog’s chest, but the tube did not move. What was wrong? I stopped to analyze the situation. Simply pushing on the chest obviously did not compress the lungs sufficiently. The problem was the rib cage. It was evident pressing on the rigid chest did not compress the lungs at all.. In order to get the proper effect, you would virtually have to crush the ribs. In fact, rib fractures and crushed chests are a common complication of chest compression during CPR –cardiopulmonary resuscitation.

I decided to start again. I considered if you pushed the diaphragm upward into the chest, you would markedly reduce the volume of the chest cavity, which would compress the lungs in a very even manner. Moving below the rib cage, I pressed my fist above the dog’s belly button and just under the rib cage, thereby pushing the diaphragm upward into the chest.. Instantly the tube shot out of the animal’s mouth! Repeating this procedure, I found the same result every time. I was extremely excited! With only a little bit of exertion, I found that pushing upward on the diaphragm drove air out of the lungs, creating a sufficient flow of air to carry the object away from the airway and out the mouth..

I quickly sent my assistant to the hospital cafeteria for a piece of meat. Putting the meat into the animal’s larynx or trachea, I again pressed the chest repeatedly. Nothing happened. Then I pressed upward on the diaphragm. The meat shot out of the dog’s mouth! I repeated the procedure over and over. Each time it worked. At first, I thought the object would have to be stuck tightly in the windpipe, like a champagne cork, in order to create enough pressure to pop it. As I experimented, however, I found that even with a partially obstructing object like a chicken bone, the flow of air past the object was enough to push it upward and out of the mouth. It was the flow of air, as in a small hurricane, not pressure, that carried the object away.

What was the actual measure of airflow? I soon discovered that by carrying out a series of tests with ten of my fellow doctors and hospital residents, the air flow was fairly easy to calculate.

One at a time, each of us was fitted with a mouthpiece that connected by tubing to a machine that measured the flow of air passing out of our mouths when the diaphragm was forced upward with a fist. Today, of course, the results would be measured by computer but in our day it was measured by a graph on a rotating drum. The figures were astounding. The average flow generated was 205 liters/minute, more than enough to drive a trapped object out of the throat. The pressure was minimal, in keeping with the engineering saying, “The higher the flow, the lower the pressure.”

But how to administer this effort? The technique had to be simple. When a child chokes on something, the parent has less than four minutes to save him from death or permanent brain injury. You couldn’t depend on a household instrument because you might not be able to locate it. You certainly couldn’t call 911; it would take emergency teams too long to respond. It had to be a procedure that could be performed by anyone. Furthermore, it had to be simple enough to be disseminated throughout the population, since you never know where or when the next choking incident would occur.

There were several choices. You could brace the victim’s back against a wall and push with your fist against his or her upper abdomen. You could lay the victim on the ground and push with your hand or foot on the upper abdomen. However, after many tests and trials, it became obvious that the best technique was to stand behind the victim and reach around the choking person’s waste with both arms. Make a fist. Place the thumb side of your fist below the rib cage, just above the belly button, grasp the fist with the other hand and press it the fist inward and upward. Perform it firmly and smoothly and repeat until the choking object is dislodged from the airway. In most reports the object flies out of the mouth and sometimes hits the wall or even the ceiling. I called this method “sub-diaphragmatic pressure.” It can be mastered in one minute from a poster. To learn it, you do not even need to take a first-aid course.

Still, there were other considerations. Suppose a person faced a choking victim of such large stature that the rescuer could not reach around the victim’s waist? Suppose a small woman or child was trying to save a large man? What happens if the victim has lost consciousness and fallen to the floor? Was it necessary to lift the victim to a standing position? What if he or she were too heavy?

To plan for these contingencies, I also developed an alternate lying-down position for the Maneuver. With the victim lying down on his back, the rescuer kneels astride the victim’s thighs, facing him. Then she places one hand on top of the other and puts the heel of the bottom hand on the same spot, just above the belly button and under the rib cage. The rescuer can use her body weight to overcome the size differential. This has made it possible for any diminutive individual to save a large or overweight person or even the youngest child has saved a parent. .

By 1974 I believed my research was complete. I had enough evidence to introduce the technique to the public. I was anxious to get started because people were choking to death every day. It was necessary to educate the entire population as soon as possible.

The Heimlich Maneuver is not designed as a professional practice; it is something that can be performed by anyone. I knew it would save lives.

But how were we to go about this? Setting up controlled experiments in hospital emergency rooms would be useless if not impossible. Yet without some sort of data, most medical journals were not likely to accept anything for publication. Even then, the public wouldn’t necessarily learn about it. It often takes a long time for articles in medical journals to filter down to the public.

And so I decided to approach Emergency Medicine, which had published some of my previous work and I knew the editor. The magazine often included accessible digests of recent research that had appeared in technical journals. I called the editor. “I have devised a method for saving the lives of choking persons,” I told him. “I’m sure it will work. If you publish it, I’d like you to alert a certain medical reporter.” After reading the article, he agreed.

At the time, doctors generally considered it unethical to talk to the press. Today, doctors, hospitals, clinics, and drug companies advertise themselves and their products on television, full pages in newspapers, and through the mail. I don’t know whether the old way or the present way is right. The best way is obviously the one that saves most lives.

“Pop Goes the Cafe Coronary” (the editor’s title) appeared in Emergency Medicine in June 1974. The term “CafÈ Coronary” had emerged to describe the frequent situation where a person chokes to death on food in a restaurant. More often than not, horrified onlookers thought the person was having a heart attack. (This was before a universal symbol for choking that I designed – hold your hand around your throat – was widely popularized.) Even the best doctors didn’t know what to do about choking. In my article, I described one incident where a physician had tried to perform a tracheotomy with a kitchen knife on his choking wife. He literally slit her throat, cutting her carotid artery in the process, and she died of a hemorrhage. Yet, one of the recommendations, before the Heimlich maneuver came along, for saving choking victims was to slit open the trachea in the neck with a knife.

Arthur Snider, a medical reporter on the Chicago Daily News who had reported on my esophagus operation twenty years before, wrote a syndicated column that appeared in several hundred newspapers on June 16, 1974. It repeated what I had said in my scientific article: Dr. Heimlich doesn’t know that his method will save a choking person, but the alternative is to let a choking person die. We did not have to wait long for results.

A week later, the following article appeared on the front page of the Seattle Times: