The Stethoscope

The stethoscope is a device that doctors can use to listen to the internal sounds of a patient’s body. It was invented in 1816 by Rene Laennec in France and the first American stethoscope was patented in 1882 by William Ford. The basic structure of the stethoscope hasn’t changed much since its original invention. The head of the stethoscope has a diaphragm, which transmits sound when it is applied to a patient’s skin. From the head of the stethoscope there is a plastic tube, which conducts the sound. The doctor listens to the sound through two earpieces.  

Before advanced medical imaging, before modern medications and advances in surgery, the physical examination and the stethoscope were the only ways for doctors to diagnose and follow heart disease. A patient’s pulse was examined and characterized. A doctor would auscultate the heart and analyze each sound, click and heart murmur. Each murmur was further characterized by putting a patient through maneuvers such as squatting, deep breathing, standing and leg raising. This helped determine the cause of the heart murmur. These physical examination techniques are still taught in medical school today.  Since there wasn’t any other way to diagnose a patient and only a few therapeutic options to discuss, the doctor spent quite a lot of time doing the physical examination.

The stethoscope of today is quite similar to the original models. The acoustics have improved, but it remains an analog device. Electronic stethoscopes have been developed which improve the acoustics, and give the ability to amplify, record, and download the heart sounds to a computer.  Most doctors still carry the old analog device, but the newer stethoscopes as well as hand held ultrasound devices (which give both acoustic and visual images of the heart) are being used more and more. Despite the improvements in technology, it has been shown that doctors’ ability to diagnose heart murmurs by physical examination is getting worse over time. Younger doctors and medical students cannot identify murmurs as well as older physicians. There are several reasons for this. Despite the fact that physical examination techniques are still taught and tested in medical school and in training, there is far less emphasis on developing these skills. In addition, in the typical patient encounter, there is much less time to do as extensive an evaluation as in the past. Lastly, with medical imaging such as echocardiography so readily available, there is less reliance on the stethoscope since an ultrasound of the heart can give a better, more accurate diagnosis. In fact, in some medical circles, the physical examination is felt to be a dinosaur and worthless in the diagnosis and treatment of the modern patient.

I still carry and use an analog stethoscope. It is around my neck from the time I leave the house until I return home, often more than 12 hours per day. On days off and on vacation, I feel naked without my stethoscope. My stethoscope requires some maintenance (I clean and disinfect it regularly), but it is always available and ready to use. It is never down due to a power outage or because of a hardware failure. I never have to upgrade its software.   I listen to every patient I see with my stethoscope. I can tell if a patient’s lungs are filling with fluid or if there is a new or changing heart murmur. I can tell if the heart rhythm is regular or not. Most importantly, it brings me close to the patient and gives me a physical connection to them. There is still great value in that.