How to listen to lung sounds

As he places the stethoscope on your back, the doctor says, "Take a deep breath."

As an RT who has listened to the lung sounds of over 10,000 patients, I will tell you that having a patient take in a deep breath is not the ideal way to listen to lung sounds.

Ideally, you want the patient to breath normal. The reason is you want to hear what a patent's lungs sound like when he is breathing normal.

When a patient is taking in a deep breath, you will have more turbulence in the lungs, and you will hear a lot of extra noises, particularly upper airway noises, and secretions sitting in the throat. Throat noises are often mistaken for wheezes caused by bronchospasm.

So, here is an RT 101 coarse on how to listen to lung sounds. If I disagree with what you learned in RT, RN or DR school I apologize. But this is how you hear lung sounds.

First, you listen to the apices while the patient is breathing normal. Many times, though, the patient could have the worse lung sounds and still sound clear in the front, so this should never be the only place you listen.

Second, while the patient is still breathing normal, you'll want to listen to the right upper lobe and then left upper lobe, and then right lower lobe and left lower lobe. You do this because you want to make sure the lung sounds are equal on both sides.

If lung sounds are not equal, this may be indicative of whatever illness is ailing the patient. For example, crackles in one part of lung may be indicative of pneumonia. Diminished in one lobe may be indicative of pneumonia or pleural effusion or pneumo.

If a patient has fine crackles in the bases, you sometimes will not hear them unless the patient takes a deep breath. So, third, you have the patient take a deep breath while you listen to the bases for those fine crackles. This is how you hear your fine crackles.

Many times these crackles get missed by nurses, doctors and probably even some RTs. But never me.

Many times, if the crackles are equal in both bases, this may be a normal sound, particularly in COPD and CHF patients. However, fine crackles in the bases can be an early sign that the lungs are getting wet, and you should check the patients urinary output to see if he is retaining fluid.

See, by your proper lung assessment, you can easily prevent a patient from ever getting short-of-breath due to wet lung. And the Dr. and RN might even be impressed with you (or their faces might be red because they failed to listen at all).

Okay, by now you have heard all your lung sounds right? Wrong. When you listened you heard a loud wheeze throughout the lungfields. This "wheeze" may also even be audible.

Here is something I learned by experience and not through school: If the wheeze is audible it is not bronchospasm: it is a throat wheeze. Many times when a patient is wet he has a throat
wheeze, so when I hear this I assess for wet lungs while auscultating.

So, we have to add a fourth step that most doctors miss.

Fourth, listen to the patient's throat. If you hear the wheeze loud in the throat, there is a high likelihood that it is not a bronchospasm wheeze. It is probably a wheeze caused by phlegm in throat, or a dry throat, or snoring, or maybe even stridor.

Many times, doctors order breathing treatments just because a patient has throat wheezes that are RADIATING throughout the lungfields mimicking a bronchospasm wheeze. Many times this throat wheeze is laryngospasm, such as you might hear after a bronchoscopy or extubation.

If you follow these four simple steps you will always get accurate lung sounds. Then you go look at the chart to see what the doctor charted: "wheezes." Then the order says, "Albuterol Nebs Q4 ATC."

As a smart RT or smart RT student or smart RN you question the doctor: "What kind of wheezes? Where are the wheezes?"

You know that they are not bronchospasm wheezes, but the doctor doesn't. While you once thought a doctor could do no wrong, you now know better. You may even snicker.