The Causes of Bradypnea and its Treatments

Bradypnea can lead to tiredness, weakness, dizziness and confusion, among other symptoms. Today's article will explain why it occurs and the available treatments.

Written and verified by the doctor Leonardo Biolatto.

Last update: 15 December, 2022

Bradypnea is a medical term used to refer to a lower than normal breathing rate. Breathing is the process by which the lungs exchange gas. The body releases carbon dioxide to the outside world and takes in oxygen by breathing.

Oxygen is essential for the cells to perform their functions. More carbon dioxide accumulates and the amount of oxygen reduces when there are fewer breaths than usual. It can lead to complex consequences.

Bradypnea has multiple causes and not all of them are malignant. However, it can be indicative of seriousness in certain situations.

We’ll explain everything you need to know about it in this article.

What is bradypnea?

The word “bradypnea” comes from Greek. Bradys means “slowness” and pnein means “breathing.” Thus, this medical term is used to refer to a lower than normal respiratory rate, according to an article from Clínica Universidad de Navarra.

We determine normality according to the age and activity level of each person. In an adult, breathing between 12 and 20 times per minute is normal. However, bradypnea is present when the rate drops below 12.

In addition, the condition is usually considered when maintained for more than two minutes. The problem is this term tends to be confused with others, such as apnea or dyspnea.

Dyspnea refers to the difficulty in breathing or the sensation of lack of air. Similarly, apnea is the temporary cessation of breathing. Furthermore, both bradypnea and apnea occur in certain people during sleep.

The opposite of bradypnea is tachypnea. The breathing rate is faster than normal in this case and it can lead to problems. A person is considered tachypneic when they breathe more than 25 times per minute.

As stated in an article by the Fundación Argentina del Tórax, alcohol intoxication is one of the most frequent causes of slow breathing. However, there may be many others, as we’ll explain in the following section.

What are the causes of bradypnea?

Bradypnea isn’t a disease as such, but a symptom that can appear in many situations. As we’ve pointed out in the previous section, alcohol intoxication is one of the main causes.

This is because alcohol acts on the breathing center, inhibiting it. This action causes breathing to slow down. However, it isn’t the only substance that can lead to this problem. Many other drugs, such as opioids, are also related to it.

In fact, the combination of benzodiazepines and alcohol is one of the most important risk factors for respiratory depression. Benzodiazepines are anxiolytic drugs and many people use them.

Other substances associated with bradypnea

Bradypnea can occur as a result of multiple substances. Another of the most important toxins is carbon monoxide.

People use it relatively frequently to commit suicide. It’s a gas that can cause death when breathed at high concentrations because it produces a decrease in respiratory rate and intoxication.

Certain drugs used to perform surgical procedures can also slow breathing. Muscle relaxants (which are often benzodiazepines), anesthetics, or pain treatments (opioid derivatives) for example. It’s, therefore, important to follow up afterward.

Encephalic problems

Breathing is a complex process coordinated by different parts of the brain. The brain determines conscious breathing. However, there are also respiratory centers in the brainstem.

These centers allow breathing under certain conditions in which the brain is disturbed. For example, when there’s a tumor or traumatic injury. However, they trigger slow breathing if they take control of the act.

Electrolyte and hormonal imbalances

As we explained above, many factors influence the frequency and depth of breathing. Another reason why bradypnea may appear is the imbalance of certain electrolytes, such as potassium or calcium.

It also appears in certain metabolic diseases, such as hypothyroidism. Thyroid hormones are responsible for regulating energy consumption and body temperature, among other processes. The respiratory rate may decrease when they’re lower than normal.

The risk factors for suffering bradypnea

An article published in EcuRed explains a series of factors that increase the risk of suffering bradypnea. Some of them are advanced age, smoking, or heart disease. The same happens when a person goes into shock.

It’s also been linked to low body temperature (hypothermia) and to people who exercise intensely on a regular basis. It isn’t necessarily serious in the latter case.

Symptoms and complications of bradypnea

Bradypnea can alter the levels of oxygen and carbon dioxide in the body. Most of the symptoms that appear are due to a lack of oxygen. Fatigue, weakness, confusion, or lightheadedness are common.

In addition, people often feel dizzy or have an impending feeling of faintness. Headache and chest pain are other common signs, as are poor coordination and memory problems.

Decreased oxygen in the blood can lead to complications — this is called hypoxemia. As an article from Bell Marra Health explains, bradypnea increases the number of fainting spells and heart problems.

In fact, organs and tissues can suffer severe damage. It causes cardiac arrest and even death in the most severe cases. Other complications are respiratory acidosis and hypercapnia (high levels of carbon dioxide in the blood).

Available treatments

Bradypnea doesn’t require treatment in all cases. As we mentioned above, it often appears in a benign form — either in people used to intense physical activity or during sleep.

It’s, therefore, necessary to discriminate in which cases this sign suggests seriousness. It depends on the cause and the patient’s health circumstances.

For example, a medical approach is usually necessary when bradypnea is due to a cardiac problem. The idea is to administer the oxygen the body needs. There are various forms of artificial ventilation for this purpose.

Furthermore, supportive treatment is usually required if the cause of bradypnea is a toxic substance. In some cases, they’ll use antidotes against the substance that’s caused the condition. This is the case of benzodiazepine intoxication, which one can treat with flumazenil.

Bradypnea is a symptom, not a disease

It’s important to once again emphasize that bradypnea is a decrease in respiratory rate. Doctors usually consider it when a person takes less than 12 breaths per minute for more than two minutes.

The point is this symptom can appear for multiple reasons, such as intoxication by alcohol or other drugs, or as a result of certain underlying pathologies. Not all cases suggest a life-threatening condition, though. Thus, a doctor must discern the cause before deciding on a treatment approach.