Introduction to Lung Sounds
For each sound we provide a patient recording and explanatory text. The full courses also include a drill and an opportunity to earn a certificate of achievement.
Using this course
Each lesson in this course includes text describing the heart or lung abnormality and a simulated torso indicating the stethoscope chestpiece location. An audio recording of the sound is provided. Phonocardiograms or waveforms are included with each lesson. These waveforms can be a highly useful aid in learning to recognize heart murmurs. In addition, short videos clips illustrate the heart's motion for each abnormality. These animations indicate the origin of each murmur. Blood flow is also animated. For lung sounds, the source (location) of the sound can be revealed.
After completing a lesson, use the lesson table of contents to navigate to another lesson.
When all lessons have been completed, we recommend using the auscultation practice exercises or quiz. In order to gain a certificate of achievement, please complete the course lessons and practice drill during one session. Most users complete the course in 30-45 minutes.
Click To Begin Training Module
Lesson #1: Vesicular - Normal C203
Vesicular breath sounds are soft and low-pitched with a rustling quality during inspiration and are even softer during expiration. These are the most commonly auscultated breath sounds, normally heard over most of the lung surface. They have an inspiration/expiratory ratio of 3 to 1 or I:E of 3:1.
Lesson #2: Wheeze - Expiratory C203
Wheezes are adventitious lung sounds that are continuous with a musical quality. Wheezes can be high or low-pitched. High-pitched wheezes may have an auscultation sound similar to squeaking. Lower-pitched wheezes have a snoring or moaning quality. The proportion of the respiratory cycle occupied by the wheeze roughly corresponds to the degree of airway obstruction. Wheezes are caused by narrowing of the airways.
Lesson #3: Pleural Rubs C203
Pleural rubs are discontinuous or continuous, creaking or grating sounds. The sound has been described as similar to walking on fresh snow or a leather-on-leather type of sound. Coughing will not alter the sound. They are produced because two inflamed surfaces are sliding by one another, such as in pleurisy. During auscultation, pleural rubs can usually be localized to a particular place on the chest wall. They also come and go. Because these sounds occur whenever the patient's chest wall moves, they appear on inspiration and expiration. Pleural rubs stop when the patient holds her breath. If the rubbing sound continues while the patient holds a breath, it may be a pericardial friction rub.
Lesson #4: Bronchophony - Healthy C203
Ask the patient to say "99" several times while auscultating the chest walls. Over healthy lung areas, "99" is not understandable. This is because sound is impeded in normal lungs. Compare this voiced breath sound to the recording in the "Bronchophony - Abnormal" lesson.
Lesson #5: Stridor C203
Stridor is caused by upper airway narrowing or obstruction. It is often heard without a stethoscope. It occurs in 10-20% of extubated patients. Stridor is a loud, high-pitched crowing breath sound heard during inspiration but may also occur throughout the respiratory cycle most notably as a patient worsens. In children, stridor may become louder in the supine position. Causes of stridor are pertussis, croup, epiglottis, aspirations.
Authors and Reviewers
Heart sounds by Dr. Jonathan Keroes, MD and David Lieberman, Developer, Virtual Cardiac Patient.
- Lung sounds by Diane Wrigley, PA
- Respiratory cases: William French
David Lieberman, Audio Engineering
Heart sounds mentorship by W. Proctor Harvey, MD
- Special thanks for the medical mentorship of Dr. Raymond Murphy
- Reviewed by Dr. Barbara Erickson, PhD, RN, CCRN.
Last Update: 12/11/2022
Heart and Lung Sounds Reference Library
Diane S. Wrigley
Impact Patient Care: Key Physical Assessment Strategies and the Underlying Pathophysiology
Diane S Wrigley & Rosale Lobo
- Practical Clinical Skills: Lung Sounds
- Essential Lung Sounds
Diane S. Wrigley, PA-C
Published by MedEdu LLC
- PESI Faculty - Diane S Wrigley
Case Profiles in Respiratory Care 3rd Ed, 2019
Published by Delmar Cengage
- Essential Lung Sounds
by William A. French
Published by Cengage Learning, 2011
- Understanding Lung Sounds
Steven Lehrer, MD
- Clinical Heart Disease
W Proctor Harvey, MD
Clinical Heart Disease
Laennec Publishing; 1st edition (January 1, 2009)