Some infants can have a massive subaponeurotic hemorrhage, sufficient to cause anemia. The volume of the bleed can be estimated from the head circumference. A more accurate value can be made with a CT scan, but at greater expense.
volume of hemorrhage in mL =
= (((head circumference in cm)^3) - ((normal head circumference in cm)^3)) / (12 * (π ^ 2))
Limitations:
• Hydrocephalus, microcephalus or other deviations from normal head circumference can result in falsely low or high volume estimates
• Different racial groups will have different expected head circumferences based on gestational age.
To read more or access our algorithms and calculators, please log in or register.
