• Alveolar ventilation:FRC ratio (5:1 in infants vs. 1.5:1 in adults)
• Greater distribution of cardiac output to the vessel-rich group in infants (vessel-rich group comprises 18% of the body weight in infants compared with 8% in adults)
• Reduced tissue solubility in infants
• Reduced blood solubility in infants

FRC = functional residual capacity.