Adventitious Sounds

There are three adventitious sounds. Pleural Rub

Rhonchi

Crackles

Presence of adventitious sounds indicates an abnormality.

Pleural Rub 
Normal parietal and visceral pleura glide smoothly during respiration. If the pleura is roughened due to any reason, a scratching, grating sound, related to respiration is heard. You can hear the sound by compressing harder with the stethoscope and making the patient take deep breathes. It is localized and can be palpable.

Rhonchi 
Rhonchi are long continuous adventitious sounds, generated by obstruction to airways. When detected, note whether it is generalized or localized, during inspiration or expiration, and the pitch. Evaluate the rhonchus in upright, supine and decubitus positions.

Diffused rhonchi would suggest a disease with generalized airway obstruction like asthma or COPD.

Localized rhonchi suggests obstruction of any etiology eg; tumor, foreign body or mucous. Mucous secretions will disappear with coughing, so would the rhonchus.

Expiratory rhonchi   implies obstruction to intrathoracic airways.

Inspiratory rhonchi in general, implies large airway obstruction. Asthmatics can also have inspiratory rhonchi while it is uncommon in COPD.

Loud audible inspiratory rhonchi is called a stridor  . This is encountered with extrathoracic large airway obstruction.

High pitched rhonchi are called sibilant rhonchi.

Low pitched rhonchi are called sonorous rhonchi.

Position: Wheezing in general will get worse in supine position. The airways get smaller in supine position. Hence, the narrowing gets worse. Note the changes in intensity of localized wheezes in the decubitus position. Depending on the size of obstructive lesion and its relationship to the dimension of airway, the rhonchus can get loud, decrease or completely disappear. This maneuver is extremely useful in detecting partial airway obstructive lesions.

Crackles
Interrupted adventitious sounds are called crackles. Make a notation about timing, intensity, effect with respiration, position, coughing and character. Timing and Intensity Crackles heard only at the end of inspiration are called fine crackles  . When the surfactant is depleted, the alveoli collapse. Air enters the alveoli at the end of inspiration. This sound is generated as the alveoli pop open from it's collapsed state. When the crackles are heard at the end of inspiration and the beginning of expiration the fluid or secretions are probably in respiratory bronchiolesmedium crackles  . If the crackles are heard throughout it implies the secretions are in bronchi coarse crackles  .

Effect of Respiration and Cough Assess the effect of deep breaths and cough on the crackles. Secretions can be cleared with these maneuvers. Crackles in diffuse interstitial fibrosis and Bronchiectasis are persistent and not altered by cough  . In Congestive heart failure the crackles can disappear transitorily with deep breaths and coughing. Position In congestive heart failure the crackles are in the bases . This is a gravity dependent phenomenon. Congestion follows blood flow. Try putting the patient in decubitus position. The dependent lung will have most crackles and they will disappear from top lung. Character Various descriptive terms have been used based on the character of the crackles eg; cellophane, wet, dry, leathery etc. Cellophane crackles are encountered in patients with diffuse interstitial fibrosis . The crackles appear to be superficial and resemble cellophane crunches.

Example:
No adventitious sounds were heard. No help yet.