Crackles - Late Inspiratory (Rales)

Late inspiratory crackles (rales) begin in late inspiration and increase in intensity. They are normally higher-pitched and can vary in loudness. These adventitious breath sounds resemble the noise made when hook and loop fasteners are being separated. These sounds are heard over posterior bases of the lungs. They may clear with changes in posture or several deep breaths. They do not clear with coughing.

Auscultation Sounds

Patient Recording

Patient Recording - Half Speed

Position

The patient's position should be sitting.

Listening Tips

Features:Crackles begin in late inspiration and increase. High-pitched, variable loudness. Best heard over posterior bases of the lungs. Do not usually clear with coughing

Waveform (Phonocardiogram)

Authors and Sources

Authors and Reviewers

EKG heart rhythm modules: Thomas O'Brien.
EKG monitor simulation developer: Steve Collmann
12 Lead Course: Dr. Michael Mazzini, MD.
Spanish language EKG: Breena R. Taira, MD, MPH
Medical review: Dr. Jonathan Keroes, MD
Heart sounds and mentorship: W. Proctor Harvey, MD
Medical review: Dr. Pedro Azevedo, MD, Cardiology
Last Update: 1/8/2023

Sources

Electrocardiography for Healthcare Professionals, 5th Edition Kathryn Booth and Thomas O'Brien
ISBN10: 1260064778, ISBN13: 9781260064773
McGraw Hill, 2019
Rapid Interpretation of EKG's, Sixth Edition
Dale Dublin
Cover Publishing Company
12 Lead EKG for Nurses: Simple Steps to Interpret Rhythms, Arrhythmias, Blocks, Hypertrophy, Infarcts, & Cardiac Drugs
Aaron Reed
Create Space Independent Publishing
Heart Sounds and Murmurs: A Practical Guide with Audio CD-ROM 3rd Edition
Elsevier-Health Sciences Division
Barbara A. Erickson, PhD, RN, CCRN
Clinical Heart Disease W Proctor Harvey, MD
Clinical Heart Disease
Laennec Publishing; 1st edition (January 1, 2009)
The Virtual Cardiac Patient: A Multimedia Guide to Heart Sounds, Murmurs, EKG Jonathan Keroes, David Lieberman
Publisher: Lippincott Williams & Wilkin)
ISBN-10: 0781784425; ISBN-13: 978-0781784429
Project Semilla, UCLA Emergency Medicine, EKG Training Breena R. Taira, MD, MPH

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