You've probably noticed sounds while breathing. These respiratory sounds can suggest issues, like crackling or whistling in your lungs. They stem from the airflow passing through your lungs and respiratory system, often hinting at underlying problems like blockages, mucus buildup or lung inflammation. Healthcare professionals address these lung sounds by treating the root causes, such as pneumonia, airway narrowing or mucus accumulation in airways. Let's explore the types of lung sounds and their implications.

Distinguishing Normal Lung Sounds from Abnormal Ones

There is a vast difference between normal lung sounds and abnormal lung sounds. In a healthy individual, normal lung sounds appear smooth and rhythmic. In affected individuals, strange lung sounds such as wheezing, stridors, or crackling indicate something wrong with your respiratory system, health, and overall well-being.

Wheezing: This high-pitched whistling sound occurs during in and out breathing movements. These sounds are typically heard when exhaling air (breathing out). This sound indicates constriction in your airways and potential diseases such as Chronic Obstructive Pulmonary Disease (COPD), Pneumonia, Bronchiolitis, and Asthma. The pitch of this sound may vary depending on the severity of the condition. Other potential issues that make you wheeze are Sleep Apnea, Lung Cancer, GERD (Gastroesophageal Reflux Disease), vocal cord problems and more. Wheezing can also occur as a side effect of certain medications, particularly those causing bronchoconstriction, non-selective beta-blockers, and more.
Crackling (or Rales): Crackling sounds, otherwise known as Rales, occur in the form of discreet sounds that mimic the sounds of rubbing, bubbling, clicking, or rattling. These sounds can vary in intensity and indicate several underlying respiratory problems. Crackling sounds typically occur during breathing in (inhaling) respiratory movements. These indicate alveoli in the lungs or fluid accumulation in the small airways. Crackling sounds are mainly caused by Cystic fibrosis, heart disease, pneumonia, COPD, specific lung infections, and more.
Stridor: Stridors are very harsh and noisy lung sounds that occur with every breath. These sounds indicate blockages within your respiratory system, especially your airways, such as the trachea or larynx. These sounds can be noticed while breathing air as the air enters your narrowed air passage. Stridors can result from various reasons, such as congenital abnormalities, airway infections, paralysed vocal cords, narrow voice box, windpipe (trachea) infection, epiglottitis, or swelling due to inflammations.
Whooping: These are high-pitched sounds that occur during breathing in just after forceful coughing. Infants and young children are more prone to whooping cough and lung sounds, necessitating vaccination for prevention. These sounds are often associated with pertussis, also known as whooping cough. Whooping is caused by the Bordetella pertussis bacterium, which infects the respiratory system, leading to intense coughing spells and the characteristic whooping sound during the subsequent inhalation.
Rhonchi: Rhonchi are low-pitched sounds that mimic snoring or rumbling sounds and often occur during breathing out. Rhonchi indicate obstructions in the aerial passage due to mucus thickening of bronchial tubes. This type of lung sound is associated with certain medical conditions such as Bronchiectasis, chronic bronchitis, pneumonia, or Chronic Obstructive Pulmonary Disease (COPD), necessitating immediate evaluation of the underlying cause.
Mediastinal Crunch: Otherwise known as Hamman Hamman's sign, it is a type of lung sound associated with a rare phenomenon. These sounds indicate air being trapped in the space between the lungs. As the name suggests, this is a crunchy or popping sound that occurs in rhythmic flow with your heartbeat. This happens because the heartbeat shifts the trapped air, resulting in scratching sounds. These crunching sounds also indicate a collapsed lung, accompanied by chronic chest pain and shortness of breath.
Pleural Friction Rub: This lung sound is exceptionally rough and associated with grating or rubbing sounds. As the name says, the Pleural Friction Rub occurs between the membrane covering the chest cavity and the outer surface of your lungs, called the pleura. These sounds are associated with conditions like pleuritis or inflammation of the pleura. This audible friction rub is heard during both inhalation and exhalation.

Conclusion

Recognising lung sounds is helpful in the timely diagnosis and treatment of the underlying medical condition. The pattern of these sounds further helps healthcare professionals to curate an appropriate and effective treatment plan for conditions ranging from pneumonia and asthma to more severe diseases such as Chronic Obstructive Pulmonary Disease (COPD) in individuals.

Frequently Asked Questions About Lung Sounds

Q1. What are the common types of lung sounds?
A1. Wheezing, Crackling, Stridor, and Whooping are the most common types of lung sounds.

Q2. What is the difference between stridor and wheezing?
A2. Stridor is a high-pitched, noisy sound that occurs with every breath. Wheezing is a high-pitched whistling sound only during exhaling (breathing out).

Q3. Which sound does COPD create?
A3. COPD manifests as wheezing, rhonchi, and crackling lung sounds.

Q4. Where are the lung sounds best heard?
A4. The lung sounds are best heard in the chest area, including the collarbones and the bottom of the ribcage.

Q5. What causes crackles?
A5. Crackling sounds occur during inhalation due to medical conditions such as pneumonia, heart failure, bronchiectasis, etc.

References:

https://my.clevelandclinic.org/health/symptoms/25193-lung-sounds