When a stethoscope is placed on a patient’s chest, the diaphragm on the device vibrates from the sounds in your body, sending back sound through the tubes and into the ear pieces, Avacare Medical explains. This is when your doctor will be able to hear your heartbeat and if there are any murmurs present, depending on the side of the stethoscope used. For example, to hear heart murmurs, doctors will likely use the bell side of the stethoscope because it picks up low-frequency sounds. Each sound wave bounces off the tube’s walls through a process known as multiple reflection.
While a stethoscope is primarily used to listen to the heart and lungs, there are many other uses as well. It’s utilized to identify bowel sounds and detect abnormal blood flow, according to Inside First Aid. Blood flow issues can be identified through a specific “whoosh” sound through a stethoscope. You’ve also possibly seen your doctor use the stethoscope for measuring blood pressure. The stethoscope is used to listen to heartbeats directly underneath the blood pressure cuff.