From the Guidelines
A normal respiratory rate in newborns ranges from 30 to 60 breaths per minute. This relatively rapid breathing pattern is normal for infants and gradually decreases as they grow older. Newborns breathe faster than adults because their lungs are smaller and less developed, requiring more frequent breaths to maintain adequate oxygen levels. Their respiratory muscles are also less efficient, and they have higher metabolic rates that demand greater oxygen consumption. It's essential to note that a newborn's breathing may appear irregular at times, with brief pauses followed by periods of faster breathing, which is typically normal. According to the study by 1, the size of the QRS complex and the baseline may wander in a cyclic fashion with respirations, and it should be noted that the neonate breathes from 30–60 times per min. However, if a newborn's respiratory rate consistently exceeds 60 breaths per minute, falls below 30 breaths per minute, or if the infant shows signs of respiratory distress, immediate medical attention should be sought as these could indicate respiratory problems. The World Health Organization (WHO) also provides guidelines on respiratory rates, as mentioned in the study by 1, but the most relevant and direct information for newborns is provided by 1.
Some key points to consider when evaluating a newborn's respiratory rate include:
- The respiratory rate can be affected by various factors, such as altitude, as mentioned in the study by 1
- Manual measurement of respiratory rate can be imprecise and is affected by intra-observer variation
- Newborns have higher metabolic rates and less efficient respiratory muscles, which can affect their breathing pattern
- Brief pauses followed by periods of faster breathing can be a normal part of a newborn's breathing pattern.
It's crucial to prioritize the most recent and highest-quality study, which in this case is not directly applicable, but the information from 1 provides a clear and direct answer to the question.
From the Research
Normal Respiratory Rate in Newborns
The normal respiratory rate in newborns can vary, but several studies provide insight into this topic.
- A study published in 2016 2 found that the median respiratory rates for healthy term infants were 46 breaths/minute at 2 hours, and 42 to 44 breaths/minute thereafter.
- The same study established the 95th percentile as 65 breaths/minute at 2 hours, and 58 to 60 breaths/minute thereafter, while the fifth percentile was 30 to 32 breaths/minute.
- Another study from 2022 3 reported a mean manual breath count of 48 breaths per minute in neonates, with a median respiratory rate variability ranging from 11.5% to 28.1%.
Factors Affecting Respiratory Rate
Several factors can affect the respiratory rate in newborns, including:
- Sleep state: Studies have shown that sleeping babies have a significantly lower mean respiratory rate than awake babies 4.
- Gender: One study found that boys had a higher respiratory rate than girls, with a mean difference of 1.6 breaths/minute 2.
- Meconium staining: The presence of meconium in the amniotic fluid can also affect the respiratory rate, with one study finding a higher respiratory rate in babies with heavy meconium staining 2.
Measurement of Respiratory Rate
The measurement of respiratory rate in newborns can be challenging due to their irregular breathing pattern.
- A study from 2022 5 found that there was poor agreement between respiratory rate measurements taken over different time periods, ranging from 15 seconds to 5 minutes.
- The same study suggested that continuous or repeated monitoring of neonates would be preferable to one-time measurements due to the high variability of respiratory rate in this population.
- Another study from 2022 3 highlighted the challenge of performing accurate respiratory rate measurements in neonates and suggested that median respiratory rate may be more reflective of the underlying physiological control of breathing.