A stethoscope is a piece of medical equipment used to listen to different sounds inside the body. It was invented by Rene Theophile Hyacinthe Laennec in 1816. Prior to the invention of the stethoscope, doctors sometimes placed their ear directly on the patient’s chest to listen to the heart. This practice was very uncomfortable for doctors and patients, especially where women were concerned. Today doctors and nurses use stethoscopes to listen to heart, lung and bowel sounds and to measure blood pressure.
Listen to the Heart
Many different heart sounds can be heard when the stethoscope is placed on the chest. Sounds of the atria and ventricles contracting and their corresponding valves can be heard. In the event that a murmur—or abnormal operation of the heart valve—is present, it can be heard as well with a stethoscope.
Listen to the Lungs
When a stethoscope is placed on the chest or back, lung sounds are heard. When the patient takes a deep breath, it is possible to hear air entering the lungs as they expand. Abnormalities in the lungs can also be heard, including crackles if fluid is present in the lungs. If airway passages are constricted, wheezing will be audible.
Listen to Bowel Sounds
Placing the stethoscope on the abdomen allows the listener to hear bowel sounds as food and liquid move through the stomach and into the intestines. Under normal circumstances, bowel sounds are low-pitched gurgles that can be heard about every five to 10 seconds. Bowel sounds may occur more or less often, or be absent depending on the patient’s condition.
Measure Blood Pressure
Stethoscopes can be used to measure blood pressure when a traditional blood pressure cuff is used. To take blood pressure using a stethoscope, place the cuff securely on the arm 1 inch above the elbow. The cuff is inflated with the attached bulb, and the stethoscope is used to listen for the pulse as the cuff is deflated.
