Which statement best describes differences in pediatric cardiovascular physiology compared with adults?

• A. Children Have Slower Heart Rates And Lower Metabolism
• B. Children Have Faster Heart Rates, Higher Metabolism, And Therefore Higher Oxygen Needs
• C. Adults Have Higher Heart Rates
• D. Oxygen Needs Are Lower In Children

Answer: (B)

The important idea is that a child’s heart rate and oxygen needs are higher relative to body size because their metabolism runs hotter and their heart is smaller. In kids, the heart must beat faster to keep enough blood flowing since the stroke volume is smaller, so cardiac output stays adequate. At the same time, children have a higher metabolic rate per kilogram, which means tissues consume more oxygen and produce more carbon dioxide per unit of body weight. Put together, kids require more oxygen delivery than adults of the same size, even at rest, and any compromise in ventilation or oxygen supply can quickly lead to hypoxia. Clinically, this means monitoring for oxygenation and ventilation is especially critical in pediatrics during sedation. The other statements don’t fit pediatric physiology: they either describe slower heart rates or lower metabolism, or claim adults have higher heart rates, or that children’s oxygen needs are lower.