Breathing is an automatic process that supplies oxygen to the body and removes carbon dioxide. The normal respiratory rate, or number of breaths per minute, varies between individuals depending on factors like age, body size, and overall health.
What is considered a normal respiratory rate?
A normal respiratory rate in adults is between 12-20 breaths per minute. However, there is some variability between individuals. Generally, the following ranges are considered normal:
- Adults: 12-20 breaths per minute
- Older children (over 12 years): 12-20 breaths per minute
- Young children (6-12 years): 15-30 breaths per minute
- Preschoolers (2-6 years): 20-30 breaths per minute
- Toddlers (1-2 years): 20-40 breaths per minute
- Infants: 30-60 breaths per minute
Respiratory rates tend to be slightly faster in females compared to males. Smaller people and children also tend to breathe faster than larger adults. Fitness level can also impact respiratory rate, with well-conditioned athletes having lower breathing rates.
What factors affect respiratory rate?
There are several factors that can influence respiratory rate:
- Age – Respiratory rates are fastest in infancy and gradually slow through childhood into adulthood.
- Body size – Smaller bodies have faster breathing rates.
- Fitness level – Well-conditioned individuals tend to have lower breathing rates.
- Health status – Illnesses that affect the respiratory system or breathing muscles can alter respiratory rate.
- Medications – Some prescription and over-the-counter drugs impact breathing patterns.
- Pregnancy – Respiratory rate increases during the third trimester of pregnancy.
- Emotional state – Stress, anxiety, or pain can temporarily increase the respiratory rate.
- Altitude – At higher altitudes, breathing rates increase to compensate for lower oxygen levels.
How is respiratory rate measured?
Respiratory rate is usually measured by counting the number of breaths someone takes over a one minute period. It can be measured when a person is at rest, breathing normally. To get an accurate measurement:
- Count breaths for a full 60 seconds, using a watch with a second hand.
- Have the person breathe normally and quietly through their nose.
- Count each rise and fall of the chest as one breath.
- Measure twice and average the numbers to get a more accurate rate.
Respiratory rate may also be monitored during exercise or while receiving medical treatment. Higher rates may be normal during physical activity or with certain health conditions.
What are signs of an abnormal breathing rate?
While there is some normal variation in respiratory rates, an abnormally high or low number of breaths per minute can be a cause for concern. Possible signs of an abnormal breathing rate include:
- Fewer than 12 breaths per minute in adults
- More than 25 breaths per minute in adults at rest
- Breathing that is rapid, deep, or labored
- Shortness of breath or difficulty breathing
- Gasping for air
- Breathing that uses accessory muscles in the neck, shoulders, or abdomen
- Changes in breathing rate that persist or seem unrelated to environmental factors
Slower breathing rates can sometimes indicate respiratory depression from narcotic pain medications. Faster breathing may be a sign of metabolic acidosis, lung infections, asthma, or other medical emergencies. Labored breathing or shortness of breath is always cause for medical evaluation.
What health conditions affect respiratory rate?
Some examples of conditions that can increase respiratory rate include:
- Pneumonia or other lung infections
- Asthma exacerbation
- COPD flare-ups
- Pulmonary embolism
- Heart failure
- Sepsis or systemic infection
- Anemia
- Drug overdose
- Diabetic ketoacidosis
- Anxiety disorders like panic attacks
Slower breathing rates may occur with:
- Head injuries
- Narcotic overdose
- Hypothyroidism
- Electrolyte abnormalities
- Neurological disorders like strokes
In some cases, an abnormal respiratory rate may be the only obvious sign of an underlying medical problem.
When to see a doctor
Consult a physician promptly if you or someone you know has breathing difficulties or an abnormal respiratory rate. Emergency medical care is advised if someone has:
- A respiratory rate higher than 25 breaths per minute
- A respiratory rate lower than 12 breaths per minute
- Labored breathing or shortness of breath
- Gasping for air or inability to catch their breath
- Blue tinge to skin or lips
- Confusion or change in mental status
- Chest pain
In children, seek immediate medical attention for:
- Breathing rates exceeding 60 breaths per minute in infants
- Breathing rates over 40 breaths per minute in young children
- Any signs of respiratory distress
Slower or faster breathing rates that persist or seem unrelated to exercise or health conditions also warrant medical evaluation. Your doctor can help determine if an underlying issue requires treatment.
How respiratory rate is used in medical assessment
Measuring respiratory rate is an essential part of any physical examination or medical assessment. Along with other vital signs like pulse, blood pressure, and temperature, respiratory rate gives important information about a person’s overall health status and physiological state.
Some key uses of respiratory rate measurement include:
- A screening test for medical problems
- An indicator of illness severity or progression
- Monitoring response to medical treatments
- Identifying emergency medical conditions like shock
- Determining requirements for supplemental oxygen
- Providing criteria for hospital admission or discharge
Changes in breathing rate may signal deterioration or improvement in health conditions. Faster breathing is a common and early sign of shock or worsening illness. Along with other vital signs, respiratory rate is tracked over time to assess the effectiveness of therapies and interventions.
Respiratory rate monitoring in hospitals
Hospitalized patients usually have their respiratory rates monitored at least daily. Patients in intensive care or critical care settings may undergo continuous breathing rate monitoring with electronic devices or frequent reassessments by bedside nurses.
Monitoring typically involves counting full minutes of breathing. However, nursing staff can also quickly estimate respiratory rate by observing 30 seconds and multiplying by two. This allows more frequent assessments of breath rate when needed.
Any concerning changes in a patient’s respiratory rate prompts a call to the care team for further evaluation and treatment. An elevated rate may require additional oxygen therapy while a slower rate could indicate over-sedation.
Outpatient respiratory rate monitoring
Doctors also monitor respiratory rate as part of routine wellness visits and outpatient evaluations. An age-appropriate breathing rate offers reassurance that a person’s vital functions are normal. Any unexplained variation from normal may require further assessment.
Those with chronic lung or heart disease have their resting respiratory rates measured at regular office visits. Trends over time provide insight into disease control and prognoses. An upward trend in rate may indicate a flare-up of the underlying condition. A downward trend can mark treatment success.
Tips for measuring respiratory rate
Here are some tips for accurately measuring respiratory rate:
- Use a timing device like a watch or clock with a second hand.
- Have the person sit or lie comfortably and breathe normally.
- Watch chest and abdomen movement to count breaths.
- Count breaths for 60 seconds for best accuracy.
- Count each inhalation and exhalation cycle as one breath.
- Measure twice and average numbers to confirm readings.
- Perform when the person is alert, relaxed, and at rest.
- Auscultation with a stethoscope can also quantify breath sounds.
Try to avoid measurement right after exercise or stressful events. Activities and anxiety can briefly increase respiratory rate. It’s best to assess rate after a person has been resting tranquilly for 5-10 minutes. Consistency in measurement conditions improves accuracy.
What’s a normal oxygen level?
A normal blood oxygen saturation level is between 95-100%. Oxygen saturation indicates how much oxygen the red blood cells are carrying as a percentage of the maximum amount they could carry.
Oxygen levels below 95% are considered low and indicate hypoxemia. This requires prompt medical evaluation to determine the cause. Some common causes of low oxygen saturation include:
- Pneumonia or other lung infections
- COPD exacerbations
- Asthma flare-ups
- Congestive heart failure
- Pulmonary hypertension
- Pulmonary embolism
- Anemia
- Carbon monoxide poisoning
Oxygen saturation is easily measured with a pulse oximeter device. This non-invasive tool clips onto a fingertip and beams light through the skin to detect oxygen levels. Along with respiratory rate monitoring, pulse oximetry is part of routine vital sign assessment in medical settings.
The relationship between respiratory rate and oxygen levels
There is an inverse relationship between respiratory rate and oxygen saturation. As oxygen levels drop, breathing tends to increase in an attempt to compensate. The body tries to increase oxygen intake by breathing faster and deeper when blood oxygen levels fall.
Likewise, low oxygen levels are a common cause of elevated respiratory rates. Hypoxemia stimulates breathing centers in the brain, leading to faster and deeper breathing. Conditions that impair oxygen transport or utilization typically cause increases in both rate and depth of breathing.
However, it is possible to have a low oxygen level but a normal respiratory rate, especially if hypoxemia develops gradually. Those with chronic lung disease can have blood oxygen levels below 95% but maintain a relatively normal respiration rate. Their elevated baseline rate does not increase further despite ongoing hypoxemia.
A normal respiratory rate does not always guarantee normal oxygenation. Respiratory rate and oxygen saturation provide complementary information about cardiopulmonary status and should be assessed together when available.
The impact of age on respiratory rate and oxygen levels
Both respiratory rate and oxygen saturation are impacted by age. Here is how they vary across the lifespan:
Newborns and infants
- Respiratory rate: 30-60 breaths/minute
- Oxygen saturation: 95-100%
Children and teenagers
- Respiratory rate:
Age Normal rate 2-6 years 20-30 breaths/minute 6-12 years 15-20 breaths/minute 13-17 years 12-16 breaths/minute - Oxygen saturation: 95-100%
Young adults
- Respiratory rate: 12-20 breaths/minute
- Oxygen saturation: 95-100%
Middle age and beyond
- Respiratory rate: 12-20 breaths/minute
- Oxygen saturation: 95-100%
Deviations from the normal age-specific ranges require prompt medical assessment. Both fast and slow breathing can signify respiratory problems in pediatric patients.
Normal variations throughout the day
Respiratory rates fluctuate mildly throughout the day and night. A small decline in oxygen levels also occurs during certain stages of sleep. Here are some variations that can occur:
During exercise
- Respiratory rate increases proportionately with exercise intensity.
- Oxygen levels are generally stable, but may decrease slightly during intense exertion.
While eating
- Respiratory rate may decline slightly while swallowing food.
- Oxygenation remains normal.
During sleep
- Respiratory rate drops by 2-4 breaths/minute.
- Oxygen levels can dip into the low 90s during REM sleep.
Minor fluctuations are normal, but persistent drops in oxygen level or respiratory rate require medical assessment. Both values should return to baseline when awake and at rest.
Tracking trends over time
Due to normal variation over the course of a day, isolated measurements of respiratory rate and oxygen saturation have limited value. More important is to identify each patient’s usual baseline values and monitor for trends over time.
For example, in a patient with stable COPD, a respiratory rate of 18-22 breaths/minute may be typical. An acute increase to 28-30 breaths/minute could signal a disease exacerbation requiring treatment.
Regular monitoring for trends also provides data to assess disease progression and response to therapies. An upward trend in respiratory rate or downward trend in oxygen level indicates worsening illness, while improvement trends in these vital signs reflect treatment efficacy.
Respiratory rate monitoring
Frequent respiratory rate monitoring is especially useful for:
- Patients hospitalized with pneumonia, heart failure, sepsis
- Individuals recovering from surgery
- Critically ill patients in intensive care
- Asthma and COPD during exacerbations
- Monitoring response to oxygen therapy
An increase of 5 or more breaths per minute above baseline warrants further assessment.
Pulse oximetry monitoring
Regular pulse oximetry is recommended for:
- Patients with lung or heart disease
- Overnight monitoring for sleep disorders
- High altitude travel
- Assessing need for supplemental oxygen
A drop in oxygen saturation below 90% or a 5% decrease from baseline requires prompt evaluation.
Conclusion
Monitoring respiratory rate and oxygen saturation provides valuable information about cardiopulmonary health. A normal respiratory rate in adults is 12-20 breaths per minute. Oxygen levels normally range from 95-100%. While minor fluctuations can occur throughout the day, persistent changes likely indicate an underlying medical issue that warrants assessment.
Both respiratory rate and oxygenation should be evaluated in the context of the patient’s individual baseline values. Trends over time are more significant than isolated measurements. Faster breathing and lower oxygen levels typically require prompt medical intervention to protect health.