Physical diagnosis

Hopkins' medical students learn to use their stethoscopes
Lost art of auscultation, or listening with a stethoscope, being revived in medical schools



By Meredith Cohn, The Baltimore Sun


The stethoscope may be an icon of the medical profession to most patients. But it's more of a relic to many doctors.

The device used to listen to the heart, lungs and other body parts — invented nearly 200 years ago — has been overtaken by newer, more sophisticated imaging equipment and other changes in healthcare. And some adherents to the old ways say a significant number of physicians who wear a stethoscope around their necks no longer know how to use it properly.

Some medical schools including Johns Hopkins, however, are bringing back the lost art of cardiac auscultation, or listening, as a means to sharpen their students' diagnostic skills and cut costs from excessive high-tech imaging.

"Most people who do and teach this well grew up in an era pre-[echocardiogram], when they had to rely on it for making a diagnosis," said Dr. W. Reid Thompson, pediatric cardiologist at Johns Hopkins Children's Center. "It's still a very quick, effective and powerful screening tool for many heart defects in children and a great way to follow patients with known defects to detect changes."

Thompson, 55, said that early on in his training he recognized the value diagnostically and the connection he felt to patients from listening. He began recording heart sounds, or murmurs, more than a decade ago. And he started teaching a mandatory workshop for medical students about two years ago with the collection that now includes 6,000 sounds from about 1,200 patients — perhaps the nation's largest cardiac audio library.

Most of the murmurs belong to children because that's when defects such as faulty valves and holes are usually discovered; a stethoscope won't pick up on the clogged arteries behind many adult heart troubles. And about 60 percent of kids have a murmur at one time, so distinguishing the dangerous ones from the much more common "innocent" ones with a stethoscope can save a lot of time, money and worry, Thompson said.

But studies going back more than a decade show medical students and doctors alike can't distinguish the sounds of trouble half the time or more. One study showed that experienced doctors tested no better than third-year medical students.

One study author says there are strong forces steering students and doctors away from listening. Auscultation skills are not tested on medical board exams, so prospective doctors won't always focus on them, said Dr. Salvatore Mangione, who teaches classes in physical diagnosis and medical history at Thomas Jefferson Medical College in Philadelphia.

Also doctors can see dozens of patients a day and don't have time to spend with each perfecting the skill. And extra patient time isn't compensated, though insurance generally covers imaging.

For example, Mangione said a good breast exam takes three minutes per breast. But busy doctors typically allot seven minutes total with each patient, so they skip the full assessment in favor of a mammogram. He said it's a good diagnostic tool but expensive and not necessary for all women every year.

"It's become a tech field and the art is suffering," he said. "There are some folks still fighting this battle, but it's hard because we do have fantastic technology."

Still, in addition to Hopkins, teaching continues in schools in Pennsylvania, California, Texas and Florida, among others, and technology to support it is growing too.

Hopkins, like many other schools, bases class discussion on recorded sounds that students can all hear at the same time, sent from a computer to wireless stethoscopes. Students at some medical schools also have a patient model developed at the University of Miami called Harvey, which can simulate heart and breathing sounds and pulses.

There also are more online tutorials and even iPhone applications.

Dr. John Michael Criley, professor emeritus of medicine and radiological sciences at the University of California, Los Angeles' David Geffen School of Medicine, developed one of the tutorials, which is free online at blaufuss.org.

He said auscultation used to be taught on the job in hospitals, but patients often aren't kept long enough for students to make the rounds. The patients' doctors don't even spend much hands-on time with them, rather they are sent for imaging and lab tests, interpreted by anonymous technicians with varying degrees of skill themselves.

Sometimes patients outside of hospitals can't get tests right away, so they are left to wonder if they are sick. Criley said this "all comes down to a failure at the bedside."

He said the improved technology and online tools have helped bring back some auscultation training, and he estimates about half of schools now have some program. He said young students, and even doctors, are probably the most enthusiastic about learning.

On a recent day at Hopkins, young doctors and fellows in one of Thompson's workshops did seem to revel in the mystery of the sounds. They listened to the "thump thump thumps" and answered questions on a work sheet. Are the murmurs harsh or musical? What's the duration? Where are they coming from? Do the patients need to be referred to a cardiologist?

Some murmurs sounded like blowing or clicking, and some were louder or faster.

Their diagnosis in patients could mean the difference between assurance that a murmur is "innocent" or indicates a dire condition such as hypertrophic cardiomyopathy, or thickened heart muscle, known for causing sudden cardiac death in young athletes.
 
Thompson worked with a former medical student to develop a website, called the murmurlab, accessible to any doctor or student who wants it. And he worked with Hopkins' Applied Physics Laboratory to design technology to capture sounds and images. The lab also helped create an algorithm that someday Thompson expects to automatically interpret murmurs, perhaps in rural areas or places where there aren't doctors trained in auscultation. (Thompson has a financial stake in a company developing that technology.)

Thompson said better training in auscultation should mean fewer referrals of patients with innocent mumurs to cardiologists and fewer echocardiograms that can cost up to $900 each.

"However, when we do see patients with only an innocent mumur, we can clear the air and be reassuring for the parents and the referring doctor just by confirming that no further testing is needed."

Thompson said he plans to continue teaching students and doctors at Hopkins, and even in the community.

One student who plans to use it is Sandesh Rao, a third-year Hopkins medical student who recently completed a workshop on auscultation with Dr. Bob Dudas, an associate director of medical education in the school of medicine.

"This is just scratching the surface," Rao said of the workshop. But, he said, "Eventually, I'll be a more confident and better diagnostician."

Some of the doctors trained with mumurlab say they may now think twice about a referral to cardiology for images, or more likely, they will be "smarter in communicating" what may be wrong, said Dr. C. Jean Ogborn from Hopkins' emergency department.

But after an auscultation lesson where several physicians didn't agree on diagnoses, Dr. Amy Polonsky, said she recognizes the work ahead.

"I'm a pianist and guitarist, and heart sounds have always been almost musical to me," she said. "But this is a tough skill. I think everyone hears them a little differently."

meredith.cohn@baltsun.com