What Is a Stethoscope
A stethoscope is a medical device for listening to sounds inside the body. On one end of the stethoscope is a diaphragm, a vibrating membrane designed to pick up sound. The diaphragm is connected to a hollow, air-filled tube. That tube splits in two and leads to earpieces, which the doctor wears. The stethoscope can be placed against the patient's chest to listen to her breath or heartbeat, or against the lower abdomen to listen to the intestines.
How a Stethoscope Works
The doctor holds the stethoscope against the patient's body, usually to listen to the breath or heartbeat. When the heart beats or the lung fills with air, it produces small sound vibrations through the body. These vibrations are picked up and amplified by the diaphragm. The sound passes into the tube, which transfers it into the doctor's earpieces. There are also electrical stethoscopes, which use a kind of microphone to pick up and amplify the sound. Because electrical stethoscopes can lose or distort parts of the sound, however, most doctors use the acoustic version.
What Stethoscopes Are Used for
Stethoscopes are often used to listen to the heart. A healthy heart produces a double beat with little or no other noise. These are the sounds of the heart valves closing. With a stethoscope, a doctor can detect a heart murmur--a whooshing sound after the heart beat that can sometimes indicate serious heart troubles. The exact sound of the murmur can give the doctor cues as to what is causing it. A stethoscope is also used to detect problems with the lungs. The doctor has the patient breathe deep and listens for wheezing or crackling sounds. He will also tap the patient's chest near the stethoscope and listen to the sound. A healthy lung will sound hollow, whereas one filled with fluid will not. The stethoscope can help the doctor detect lung problems such as asthma, pneumonia and bronchitis.
Tags: against patient, breath heartbeat, doctor detect, electrical stethoscopes, listen breath, listen breath heartbeat