the breathing rate of an infant is 30-50 breaths per minute while that of an adult in 18-20. why do infants have higher respiratory rates then adults?
This is not scientific, but I've noticed that smaller beings (babies, cats, dogs, etc.) breathe faster than adult humans do. It has to do with size -- size of body, size of lungs ...
The consumption of energy in prematures and newborns is primarily used to supply the heart and maintain body temperature. For newborns, the ratio of skin area to volume is lower than older children, thus it takes more oxygen to burn calories to maintain heat. Most moms recognize this, and keep newborns covered, especially from breezes. The heart pumping energy is a significant proportional user of energy in the newborn, requiring proportionally more oxygen than an older child. Finally, considering these higher uses of oxygen, and the limited lung capacity, the breathing rate has to increase in order to move more oxygen into the bloodstream per minute. Curiously, the breathing rate of prematures often exceeds 50 breaths per minute, but if you calculate the minute volume (the volume of air moved into the baby per minute), it is the same as a normal term infant.
Writeteacher is right, it has to do with size (loss of body heat), and the proportion of energy going to the vital functions (heart) as size goes down. Observe a mouse, and you really get the picture.
Infants have higher respiratory rates than adults due to several reasons:
1. Metabolic rate: Infants have a higher metabolic rate compared to adults. Their bodies are rapidly growing and developing, which requires more oxygen for energy production. A higher respiratory rate helps to deliver more oxygen to meet the metabolic demands of their growing bodies.
2. Lung size: Infants have smaller lungs in proportion to their body size. Their lung capacity is relatively smaller compared to adults, leading to a decreased ability to take in larger volumes of air per breath. To compensate for this, infants need to breathe more frequently to ensure an adequate oxygen supply.
3. Immature respiratory system: The respiratory system of infants is less developed than that of adults. The muscles involved in breathing, such as the diaphragm, are not fully developed, making it less efficient for infants to take deep breaths. Therefore, they rely on rapid, shallow breaths to maintain adequate oxygen levels.
It is important to note that the breathing rates mentioned (30-50 breaths per minute for infants and 18-20 breaths per minute for adults) are average ranges. Individual variations can occur, and any concerns about breathing rates should be discussed with a healthcare professional.