14. HEART AND LUNGS OF A CHILD

A child's heart and lungs work together to circulate blood and oxygen, with a heart rate that decreases from up to 150 bpm in infants to roughly 90 bpm in older children. Located in the chest, the heart pumps blood to the lungs to pick up oxygen, which then circulates through the body. Key differences in children include higher heart rates and smaller lung capacities. 

National Institutes of Health (NIH) | (.gov) +4

Key Aspects of a Child’s Heart and Lungs

• Heart Function & Rate: The heart is a four-chambered muscle that pumps blood throughout the body, beating an average of 90 times per minute (130-150 bpm for babies). It is located behind the breastbone on the left side.
• Lung Function & Breathing: The lungs bring oxygen into the body through the trachea, branches (bronchi), and air sacs (alveoli). The left lung is smaller to accommodate the heart. The diaphragm, a dome-shaped muscle below the lungs, controls breathing.
• Circulation: The right side of the heart sends deoxygenated blood to the lungs, while the left side receives oxygenated blood from the lungs and pumps it to the body.
• Developmental Differences: Young children's respiratory and cardiovascular systems differ from adults, making them more vulnerable to cardiac or respiratory events.
• Common Conditions: Congenital heart defects, such as structural issues, occur in 8-10 per 1,000 births.
• Health Indicators: Signs of potential heart or lung issues include rapid breathing, fatigue during activity, poor feeding, and cyanosis (bluish skin).

• Diagnostic Tools: Doctors use electrocardiograms (ECG), echocardiograms (sound waves), and pulse oximetry (oxygen levels) to monitor health. 

  The Royal Children's Hospital +7

Important Reminders

• A child's heart can be strengthened through regular exercise.
• The respiratory system includes the nose, mouth, trachea, and lungs, which filter air and allow for gas exchange.
• The heart pumps roughly 2,000 gallons of blood daily, even in children.