Rhonchi and Rales: What's the Difference?

Rhonchi and rales are sounds in the lungs that can be heard with a stethoscope. Rhonchi are described as gurgling or bubbling sounds, while rales are described as crackling. These happen when fluid in the airways due to asthma, pneumonia, bronchitis, or another respiratory infection interrupts airflow.

The characteristics of rhonchi and rales, such as whether they are heard on inhalation or exhalation, can indicate how air is moving through your lungs. This can help your healthcare provider understand what might be causing labored breathing or other symptoms.

What Are Rhonchi?

Rhonchi are sometimes called sonorous wheezes because they are similar to another breath sound called wheezing.

They can be described as low pitched continuous breathing sounds that resemble snoring or gurgling.

Rhonchi are best heard in the expiration phase of breathing (when breathing out).

Causes

Rhonchi occur when there are secretions or obstruction in the larger airways. These breath sounds are associated with conditions such as chronic obstructive pulmonary disease (COPD), bronchiectasis, pneumonia, chronic bronchitis, or cystic fibrosis.

Sometimes when you cough it removes the secretions long enough that the sounds stop for a while, they will return when the secretions (mucus) builds back up in the airways.

What Are Rales?

Rales are also sometimes called crackles, which is a good description of how they sound, often described as the crinkling up of a piece of paper or the pulling apart of two pieces of velcro.

Rales are further differentiated as fine or course with fine rales (or crackles) being high pitched and coarse rales (or crackles) being lower in pitch. They are not continuous and are heard on inspiration(when breathing in).

Causes

Rales are thought to occur when the tiny air sacs in the lungs, called alveoli, suddenly pop open in the presence of secretions. This is not entirely clear, however.

Conditions associated with the presence of rales include pneumonia, atelectasis (a condition that causes the alveoli to become collapsed in certain areas of the lungs), fibrosis of the lungs, and heart failure.

Rhonchi vs. Rales: Key Differences

It can be hard to tell the difference between rhonchi and coarse rales. There are, however, some key differences:

Diagnosis

In addition to diagnosis, listening to breath sounds is a form of monitoring the progression of a respiratory condition. This section, however, will focus on the next steps that should be taken in pinning down a specific diagnosis after a healthcare professional identifies rhonchi or rales on auscultation.

It is worth noting that addressing any immediate breathing problems such as decreased oxygen saturation should be taken care of before obtaining diagnostic testing.

If you are experiencing rhonchi or rales for the first time and the cause is unknown some of the following diagnostic tests are usually beneficial in identifying the cause:

• Chest X-rays
• Sputum cultures
• Pulmonary function tests
• Bronchoscopy
• Heart studies (if heart failure is suspected)

Treatment for Rhonchi and Rales

An individual's treatment for rhonchi and rales will look different depending on the discretion of their physician, as well as any underlying condition that may be causing these breath sounds.

However, treatment typically focuses on either the immediate relief of symptoms or addressing the underlying cause (a few treatments may be effective in addressing both symptom relief and the underlying cause).

In addition to qualified doctors and nurses, respiratory therapists are often an essential part of your medical team and play an important role in executing said treatment.

Symptom Relief

The administration of oxygen is often used for immediate relief of symptoms and is often necessary for overall well-being and health. Humidity can sometimes be added to oxygen (usually with aerosolized sterile water or saline) which is helpful in loosening, thinning, and breaking up excess mucus and may be more comfortable and less irritating to the airways.

Other methods of relieving excess secretions are also effective in mitigating symptoms at least temporarily. These may include:

• Nasopharyngeal suctioning
• Increased fluid administration (often intravenous)

Your nurse or respiratory therapist may also encourage you to exercise (usually by getting up and walking around) or to cough in an effort to manage excess secretions. In some cases, respiratory therapists may employ other methods such as percussion (shaking or vibration of the chest) or oscillation to move secretions.

Inhaled medications including bronchodilators such as Albuterol, Ventolin, or Proventil (salbutamol), are frequently used for the immediate relief of symptoms. These medications result in the dilation of the airways (increasing their diameter) which allows for more air to pass through the airways and reach the lungs.

Common side effects of these medications include:

• Increased heart rate
• Shaking
• Feeling of nervousness

These medications should not be combined with some other pharmaceuticals including certain heart medications and antidepressants.

Treating the Underlying Cause

Since each underlying root cause of rhonchi and rales is different this section will focus on a few examples of common underlying causes and briefly outline various treatments for them. For example if the cause is bacterial pneumonia antibiotics may be a necessary treatment.

Treatment of atelectasis is often increased exercise, coughing and deep breathing, and if anesthesia has been administered time may be required for the anesthetic to be metabolized (leave the body).

The treatment for chronic respiratory conditions that contribute to the presence of rhonchi and rales such as cystic fibrosis, COPD or heart failure may be much more complicated.

It may include the administration of certain medications, dietary or other lifestyle changes, low flow oxygen administration, or even heart or lung surgical procedures such as heart catheterization or transplants.

Each individual's circumstances and subsequent treatment will be unique but the goal of addressing the underlying condition will be the same.