Bradypnea is an abnormally slow breathing rate.
The normal breathing rate for an adult is typically between 12 and 20 breaths per minute. A respiration rate below 12 or over 25 breaths per minute while resting may signal an underlying health problem.
Normal respiratory rates for children are:
|Age||Normal respiratory rate (breaths per minute)|
|infants||30 to 60|
|1 to 3 years||24 to 40|
|3 to 6 years||22 to 34|
|6 to 12 years||18 to 30|
|12 to 18 years||12 to 16|
Bradypnea can happen during sleep or when you’re awake. It’s not the same thing as apnea, which is when breathing completely stops. And labored breathing, or shortness of breath, is called dyspnea.
The management of breathing is a complex process. The brainstem, the area at the base of your brain, is necessary to control breathing. Signals travel from the brain through the spinal cord to the muscles that tighten and relax to bring air into your lungs.
Your brain and major blood vessels have sensors that check the amount of oxygen and carbon dioxide in your blood and adjust your breathing rate accordingly. In addition, sensors in your airways respond to the stretching that occurs during breathing and send signals back to the brain.
You can also slow down your own breathing by controlling your inhales and exhales — a common relaxation practice.
Quite a few things can cause bradypnea, including:
Opioid abuse has reached crisis levels in the United States. These powerful drugs attach to receptors in your central nervous system. This can dramatically slow your breathing rate. An opioid overdose can become life-threatening and cause you to stop breathing completely. Some commonly abused opioids are:
These drugs may pose greater danger if you also:
- take benzodiazepines, barbiturates, phenobarbital, gabapentinoids, or sleep aids
- drink alcohol
- have obstructive sleep apnea
- have chronic obstructive pulmonary disease (COPD), lung cancer, or other lung conditions
People who ingest packs of drugs for illegal transport (body packers) can also experience bradypnea.
If your thyroid gland is underactive, you’re deficient in certain hormones. Untreated, this can slow some body processes, including respiration. It can also weaken the muscles needed for breathing and lead to diminished lung capacity.
Certain toxins can affect the body by slowing your breathing. An example of this is a chemical called sodium azide, which is used in automobile airbags to help them inflate. It is also found in pesticides and explosive devices. When inhaled in significant amounts, this chemical can slow both the central nervous system and the cardiovascular system.
Another example is carbon monoxide, a gas produced from vehicles, oil and gas furnaces, and generators. This gas can be absorbed through the lungs and accumulate in the bloodstream, leading to low oxygen levels.
Injury near the brainstem and high pressure within the brain can lead to bradycardia (decreased heart rate), as well as bradypnea.
Some other conditions that can lead to bradypnea include:
- use of sedatives or anesthesia
- lung disorders such as emphysema, chronic bronchitis, severe asthma, pneumonia, and pulmonary edema
- breathing problems during sleep, such as sleep apnea
- conditions that affect nerves or muscles involved in breathing, such as Guillain-Barré syndrome or amyotrophic lateral sclerosis (ALS)
In a 2016 study using rats, researchers found that emotional stress and chronic anxiety can lead to a decrease in breathing rate, at least in the short term. One concern is that an ongoing low breathing rate may signal the kidney to increase the body’s blood pressure. This could lead to the development of high blood pressure long term.
Symptoms that may accompany slowed breathing depend on the cause. For example:
- Opioids can also cause sleep problems, constipation, decreased alertness, and itching.
- Other symptoms of hypothyroidism may include lethargy, dry skin, and hair loss.
- Sodium azide poisoning can lead to a variety symptoms including headache, dizziness, rashes, weakness, nausea, and vomiting.
- Exposure to carbon monoxide may cause headache, dizziness, cardiovascular toxicity, breathing failure, and coma.
Slowed breathing, as well as other symptoms such as confusion, turning blue, or loss of consciousness, are life-threatening events requiring immediate emergency care.
If your breathing rate seems slower than normal, see your physician for a thorough evaluation. This will probably include a physical examination and a check of your other vital signs — pulse, body temperature, and blood pressure. Along with your other symptoms, a physical exam and medical history will help determine if further diagnostic tests are needed.
In emergency situations, supplemental oxygen and other life support measures may be needed. Treating any underlying condition may resolve the bradypnea. Some potential treatments are:
- opioid addiction: addiction recovery programs, alternate pain management
- opioid overdose: when taken in time, a drug called Naloxone can block opioid receptor sites, reversing the toxic effects of the overdose
- hypothyroidism: daily thyroid medications
- toxins: administration of oxygen, treatment of any poisoning, and monitoring of vital signs
- head injury: careful monitoring, supportive care, and surgery
If your breathing rate falls too low for too long, it can lead to:
- hypoxemia, or low blood oxygen
- respiratory acidosis, a condition in which your blood becomes too acidic
- complete respiratory failure
Your outlook will depend on the reason for the bradypnea, the treatment you receive, and how well you respond to that treatment. Some conditions that cause bradypnea may require long-term management.