What Is a Normal Respiratory Rate?

Normal, Increased, and Decreased Respiratory Rates in Adults and Children

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If you are experiencing respiratory symptoms, you may be wondering, “what is a normal respiratory rate?” Let’s begin by talking about the normal range of respiratory rate for adults and children, how to accurately measure this rate, and what it means if the rate is abnormal.

Overview

The respiratory rate is defined as the number of breaths a person takes during a one-minute period of time while at rest.

Recent studies suggest that an accurate recording of respiratory rate is very important in predicting serious medical events; studies also suggest that measurements of respiratory rate are not done as often as they should be, so it's been coined the “ignored vital sign.”

Measuring Respiratory Rate

Respiratory rate is measured by counting the number of breaths a person takes in a one-minute period. Since many factors can affect the results, understanding how to take an accurate measurement is very important.

The rate should be measured at rest, not after someone has been up and walking about. Being aware that your breaths are being counted can make the results inaccurate, as people often alter the way they breathe if they know it's being monitored. Nurses are skilled at overcoming this problem by discretely counting respirations, watching the number of times your chest rises and falls—often while pretending to take your pulse.

While recording respiratory rate, several other markers of respiratory problems may also be noted. Is your patient or loved one uncomfortable? Do the muscles in her neck tighten as she breathes? (Medical professionals call this “the use of accessory muscles” to breathe.) Can you hear any wheezing or other abnormal breathing sounds?

What Does It Measure?

The number of breaths we take per minute is a sign of how often our brain is telling our bodies to breathe. If the oxygen level in the blood is low, or alternately if the carbon dioxide level in the blood is high, our body is instructed to breathe more often. For example, having a severe infection increases the carbon dioxide produced in the body, so even if there's a normal level of oxygen in the blood, the brain instructs the body to breathe more often to clear the carbon dioxide.

But there are times when this system doesn’t work so well, such as when people are treated with narcotic medications. These medications in effect dull the response of the brain to signals from the blood, so someone may breathe less often than needed. This may also occur with head injuries that damage the respiratory center in the brain.

Normal Respiratory Rates in Children

Children have faster respiratory rates than adults, and the "normal" respiratory rate can vary significantly by age.

The normal ranges of respiratory rates for children of different ages include:

  • Newborn: 30-60 breaths per minute
  • Infant (1 to 12 months): 30-60 breaths per minute
  • Toddler (1-2 years): 24-40 breaths per minute
  • Preschooler (3-5 years): 22-34 breaths per minute
  • School-age child (6-12 years): 18-30 breaths per minute
  • Adolescent (13-17 years): 12-16 breaths per minute

Periodic Breathing in Children

Infants usually have a much faster respiratory rate than older children, and can also exhibit a phenomenon referred to as periodic breathing. With periodic breathing a child's average respiratory rate may vary widely; she may have periods during which she breathes slower than normal followed by a few minutes of breathing much faster than normal. The importance of periodic breathing is that—while it can be frightening as a parent—it is usually quite normal unless your child has other symptoms suggestive of an underlying medical condition.

Normal Respiratory Rates in Adult

As with children, the respiratory rate should be measured when a person is at rest and has not just engaged in vigorous activity. In general, respiratory rates are slightly faster in women than men.

The average respiratory rate in a healthy adult is between 12 and 18 breaths per minute.

Abnormal Respiratory Rates

Both an increased and decreased respiratory rate can be a sign that something is amiss in the body. An abnormal rate is fairly nonspecific, meaning there are many causes of both a rapid and a slow rate. It’s important again to note that the normal ranges are for people at rest. Respiratory rate normally increases during exercise.

Increased Respiratory Rate

What is an elevated respiratory rate? In adults, the cut-off is usually considered a rate over 20 breaths per minute, with a rate of over 24 breaths per minute indicating a very serious condition.

As noted above, respiratory rate is a very important vital sign. One study found that an elevated respiratory rate was a better determinant of people who were stable versus unstable than heart rate or blood pressure.

There are many causes of an increased rate, some that are related to the lungs and some that are not. Some of the more common causes include:

  • Fever - An increased rate of breathing with a fever as the body attempts to lose heat by breathing faster. This is important in that a rapid respiratory rate can be a sign of a worsening infection, and that a fever needs to be taken into account in interpreting the respiratory rate. It's thought that respiratory rate increases in children on an average of five to seven breaths per minute per degree Celsius elevation in body temperature. In young children (less than 12 months old) this does not always prove to be the case, and children may not have an increased respiratory rate in response to fever and vice versa. When they do have an increased respiratory rate, it is usually increased on an average of seven to eleven breaths per minute per Celsius elevation in temperature.
  • Dehydration – Dehydration alone can result in a rapid rate of breathing.
  • Asthma – During an asthma attack, respiratory rate is often increased. Even small increases in respiratory rate can be a sign of worsening and respiratory rate should be monitored closely if this is the case.
  • COPDChronic obstructive pulmonary disease is a common cause of a rapid respiratory rate, especially in people with a history of smoking.
  • Hyperventilation – People may breathe more rapidly in response to stress, pain, anger or during a panic attack.
  • Lung conditions – Such as lung cancer, pulmonary embolism (blood clots in the legs that travel to the lungs) or other lung diseases.
  • Infections – Common and uncommon infections such as the flu, pneumonia, and tuberculosis can result in rapid breathing.
  • In newborns, common causes include transient tachypnea of the newborn (TTN) - a mild condition - as well as conditions that are more serious, such as respiratory distress syndrome. 
  • Acidosis – An increase in the acidity of the blood results in the increased production of carbon dioxide, and hence an increased rate of breathing. This can occur when a person has a condition resulting in metabolic acidosis such as with diabetes (diabetic ketoacidosis.) 
  • Overdoses – Such as with an overdose of aspirin or amphetamines.
  • Heart conditions – An elevated respiratory rate was found in one study to be a predictor of cardiac arrest in people hospitalized with heart conditions.

In children, the most common causes of an increased respiratory rate include a fever or dehydration. Conditions such as bronchiolitis and pneumonia are relatively common. Children may also have causes of a rapid respiratory rate similar to adults, such as acidosis (with diabetes) and asthma.

Decreased Respiratory Rate

A lowered respiratory rate, defined as a rate less than 12 by some, or less than eight respirations per minute by others, can also be a sign of concern. Some causes of a decreased rate include:

  • Use of narcotics – Some medications such as narcotics, whether used for medical purposes or illegally, can suppress respiration.
  • Alcohol – Consumption of alcoholic beverages can decrease respiratory rate.
  • Metabolic – Respiratory rate can decrease in order to balance the effects of abnormal metabolic processes in the body.
  • Sleep apnea – With sleep apnea, people often have episodes of apnea and a decreased breathing rate mixed with episodes of an elevated breathing rate.
  • Brain conditions – Damage to the brain, such as strokes and head injuries often result in a decreased respiratory rate.

Dyspnea: Sensation of Shortness of Breath

It's important to make a quick note that the rate of breathing is separate from the sensation of feeling short of breath. Sometimes the respiratory rate may affect whether or not someone feels dyspneic, or short of breath, but other times may not. Someone may feel short of breath with a very rapid respiratory rate, and may not feel short of breath with a very low respiratory rate.

Medical Terminology

Medical professionals use several terms to describe abnormal respiratory rates. Some of these include:

  • Bradypnea – Bradypnea is the medical term used to define breathing that is abnormally slow.
  • TachypneaTachypnea is the medical term used to define an elevated respiratory rate. This rapid respiratory rate is usually shallow, versus hyperpnea which can be rapid and deep.
  • Dyspnea – Dyspnea refers to the sensation of shortness of breath, and can occur with an elevated, a normal, or a decreased respiratory rate.
  • Hyperpnea – Hyperpnea refers to breathing that is abnormally deep and appears labored. It may occur with or without rapid breathing.
  • Apnea – Apnea means literally “no breath” and refers to the absence of breathing.

A Word From Verywell

While many people think first of their pulse or blood pressure, we're learning that measuring respiratory rate is just as important. Certainly, respiratory rate can be influenced if you know your breathing rate is measured, so it's important for health care providers to become proficient in discreetly measuring this rate. Both an increased and a decreased respiratory rate can be a warning sign of underlying medical conditions and should be heeded.

It's important to again emphasize the significant differences between the normal respiratory rates of adults and children. Those who care for children should familiarize themselves with these ranges, and be aware of when breathing is too fast or slow.

Sources:

Flenady, T., Dwyer, T., and J. Applegarth. Accurate Respiratory Rates Count: So Should You!. Australas Emergency Nursing Journal. 2017 Jan 7. (Epub ahead of print).

Kliegman, Robert M., Bonita Stanton, St Geme III Joseph W., Nina Felice. Schor, Richard E. Behrman, and Waldo E. Nelson. Nelson Textbook of Pediatrics. 20th Edition. Philadelphia, PA: Elsevier, 2015. Print.

O’Leary, F., Haven, A., Lockie, F., and J. Peat. Defining Normal Ranges and Centiles for Heart and Respiratory Rates in Infants and Children: A Cross-Sectional Study of Patients Attending an Australia Tertiary Hospital Paediatric Emergency Department. Archives of Disease in Childhood. 2015. 100(8):733-7.

Parkes R.Rate of respiration: the forgotten vital sign. Emergency Nurse. 2011. 19(2):12-7.

University of Iowa Health Care.Pediatric Vital Signs Normal Ranges.https://iowaheadneckprotocols.oto.uiowa.edu/display/protocols/Pediatric+Vital+Signs+Normal+Ranges

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