How to Auscultate Lung Sounds

Auscultating lungs is a vital skill that Paramedics need to develop to be good Paramedics. The easiest way to develop this skill is to listen to as many chests as possible. This includes good, health chests, as much as sick chests. Without listening to healthy lungs, how will you know the difference with un-healthy lungs? These are the steps that I use:

1.      Minimize the noise in the room. This includes: turning off the television and radio and if the Ambulance is moving, you may have to stop the Ambulance so that you can clearly hear the lung sounds.

2.      Explain to the patient what you are going to do.

3.      Make sure the diaphragm of the stethoscope is turned on. Put the ear pieces in your ears and gently tap on the flat diaphragm. If you can’t hear anything, turn the head of the diaphragm to turn it on.

4.      Have the patient sit upright if possible. Start in the upper lung fields. Place the diaphragm of the stethoscope on the patient’s upper back on the left side to listen to the posterior upper lobes of the lungs. Although a thin hospital gown or t-shirt should not interfere with auscultation, it’s best to place the stethoscope on bare skin.

5.      Instruct the patient to take a deep breath through her mouth. As the patient inhales, listen to the sounds in the lungs. Move the stethoscope to the opposite of the body, but at the same level. Always listen to both sides of the lungs to compare the sounds. Every time you listen to a new segment of the lung have the patient inhale. Follow this diagram to determine where to auscultate**

6.      Move the stethoscope down a few centimeters and listen to another segment of the lung on both sides.

7.      Put the stethoscope on the front of the patient’s chest to listen to his anterior lobes of the lungs. Repeat the same pattern as with the back, starting at the top and working your way down. Listen to one side of the body and move to the other.

8.       Identify abnormal lung sounds. The most common abnormal lung sounds include wheezing, stridor and crackles. Each has a distinctive sound and possible cause. Wheezing is often caused by constricted airways and is a high-pitched sound and may occur with asthma or emphysema. Crackles sound similar to snoring and can occur with fluid in the lungs caused by a condition such as congestive heart failure. Stridor may indicate croup and is a narrowing of the upper airway. It usually sounds like wheezing on exhalation over the trachea. Crackles sound like bubbles popping and can occur with pneumonia due to the fluid in lungs.

9.      Document what you have heard and re-evaluate to determine if your treatment has changed anything.