Doctors used to just put an ear up to a patient's chest and listen. Then, in 1816, things changed.

Thirty-five-year-old Paris physician Rene Laënnec was caring for a young woman who was apparently 'plump' with a bad heart and large breasts. Obstetrician George Davis, who collects vintage stethoscopes, says the young Dr. Laënnec didn't feel comfortable pressing his ear to the woman's bosom.

"So he took 24 sheets of paper and rolled them into a long tube and put that up against her chest, listened to the other end and found that not only could he hear the heart sounds very, very well, but it was actually better than what he could hear with his ear," said Davis, who cares for high-risk pregnant women at East Tennessee State University Medical Center.

That's a nice story about ingenuity and chivalry. But some other sources say it was actually 19th century hygiene--lice and the smell of unwashed bodies--that kept Laënnec from getting too close to his patient.

Either way, the young doctor went home and crafted a wood cylinder with a hole down the middle, and that became the first stethoscope.

It took a while for auscultation—the art of intentional listening--to catch on. But the new tool fit into an evolving idea at the time that doctors needed a more focused approached to diagnosis—"that you should distinguish tuberculosis from a lung abscess—and not just call it all consumption," said Steven Peitzman, a professor at Drexel University College of Medicine.

As stethoscopes evolved, they amplified the sounds of a healthy heart and let doctors hear the offbeat, cadence of a problem rhythm. 

Recent debates about the stethoscope's relevance have largely focused on the heart, but move the chest piece to the lungs, and you can hear telltale high-pitched crackles that are often a sign of pneumonia. Move the stethoscope down more, listening to the bowels after surgery, which is one of the best ways to make sure digestion is back to normal, Davis said. 

Peitzman says the stethoscope is nearly irreplaceable for monitoring the wheeze of asthma. He graduated from medical school in 1971, and says physicians used to get praise if they had the 'ear' to hear and interpret the subtle body sounds that travel through a stethoscope's rubber tubing.

A stethoscope is reliable, cheap—and ready: there's no need to recharge it, Peitzman said. He keeps a $5 spare in his car just in case.

An icon

The stethoscope has been the iconic symbol of a physician for a long time and comes with some nostalgia.

Vidya Viswanathan, a first-year student at the University of Pennsylvania's Perelman School of Medicine, is still getting used to her stethoscope.

"You don't realize until you are wearing it and trying to use it, how pokey it is in your ears, said the 26 year old from Long Island, New York. "I'm almost embarrassed to wear it because it implies I have knowledge I don't have yet."

Viswanathan's mom is a pediatric oncologist. Her stethoscope always has a charm with the latest Disney or cartoon character dangling from it. As a little girl, Viswanathan says she loved the way her mother handed over the earpieces to let patients hear for themselves.

"I think they liked the attention of having their lung sounds listened to with the stethoscope," she said.

Viswanathan says she thought all physicians used their stethoscope as a tool to connect. But as an adult, she's noticed that for some doctors, the stethoscope exam seems like just another thing to check off the list.

In the debate over the stethoscope's relevance, many argue that if you lose the stethoscope, you lose the tradition of healing touch. But emergency medicine doctor Bret Nelson says there are other ways to bring patient and physician together.

"Pulling an ultrasound machine out of my pocket, or wheeling the cart over next to the patient, talking through with them exactly what I'm looking for and how I'm looking for it, the fact that they can see the same image on the screen that I'm seeing--strengthens that bond more than anything in the last 50 years," Nelson said.

Today's stethoscope debate is really a fight about young, soon-to-be-doctors, like Viswanathan. What skills will they need and what should medical schools be teaching them?

Steven Peitzman, who teaches medical students at Drexel, says basic stethoscope skills are still essential, but he's lowered his ambition for medical students.

"I'm also realistic with them," Peitzman said. "If you are going to be a dermatologist you shouldn't spend a lot of time trying to get good at detecting heart murmurs, which can be at the threshold of human hearing. But if you are going to be a generalist physician, at least be able to identify if there is a murmur or there's not a murmur."

Brett Nelson says the stethoscope is on its way out: "It's time has come."

He directs the emergency department's ultrasound program at Mt. Sinai Hospital in New York. Nelson says stethoscopes are ubiquitous in medicine—around the necks of physicians, nurses, technicians and phlebotomists. That makes the stethoscope a little less relevant as a symbol, he says.

"There's this expectation that having a stethoscope means you can take care of people like putting on a white coat means that you're probably a doctor--or a butcher or some other person who needs to wear a white coat," Nelson said.

Clinicians now get a lot more information from newer technology. An ultrasound, for example, turns sound waves into moving images. You can watch blood pumping and see heart valves click open and shut.

Nelson teaches medical students and says it's helpful to show new learners what lies beneath. For many, visual cues are easier to interpret than muffled murmurs, he said.

Stethoscope skills often diminish as a doctor progresses in her career, and a 2014 study suggests that for heart conditions in particular, imaging leads to a more accurate diagnosis than a physical examination.

At Mt. Sinai, when medical students are taught to examine a heart, they learn stethoscope and ultrasound skills—all on the same day.

"They know how to feel it, they know how to listen to it, and they know how to look at it," Nelson said.

Obstetrician George Davis says high-tech machines and imaging scans are great as back up, but his stethoscope helps him figure out which patients actually need that additional testing.

"How much do those ultrasound machines cost?," he said. "I can get a good stethoscope for less than $20.  We are not going to sit there and do an echocardiogram on every patient who walks through the door."

Davis is worried that a whole generation of physicians is learning to rely more on technology and he wants to hold on to first-line tools that are safe, effective and cheaper.

"Shouldn't we be using what is low-tech and practical?" he said.

Ultrasound specialist Brett Nelson counters that point-of-care imaging is becoming less expensive every day. Twenty years ago, an ultrasound machine was as big as a refrigerator and cost $400,000.

Today, a handheld, portable device plugs into a computer tablet, and costs less than $10,000, he said, adding that many generalists and primary care providers in the community may have an ultrasound in their pocket soon. 

"It's probably as realistic as me telling you that they're all going to carry in their pocket a slide rule, a calculator, a flashlight, a phone, a computer terminal and 36 video games," he said. That's what most people have on their smartphone now.

Daniel Shindler--a professor at the Rutgers Robert Wood Johnson Medical School--says cardiac ultrasound has been his love and special interest for decades. He's excited to share the potential of that technology and recently hosted a party for medical students to teach them handheld ultrasound skills. Still, he's not giving up his stethoscope.

"The stethoscope and the ultrasound machine have played nicely together for a long, long time; they will continue to do so," Shindler said. "My interaction with a patient is: I have conversation with them, and then put the stethoscope on the chest. If I didn't put my stethoscope on your chest, I didn't talk to you."