During the first week after birth, some
premature infants develop bleeding in the brain
(intraventricular hemorrhage), for which there is no known treatment. Bleeding
severity is most often minimal (grades I and II) and causes little or no
noticeable brain damage. Grade III bleeding raises the risk of developing
hydrocephalus (a buildup of excess cerebrospinal fluid
within the brain), brain damage, or both. Grade IV is used to describe
extensive bleeding that has damaged brain tissue and shows up on
image tests.
The more immature the
brain, the more fragile the brain's blood vessels and the more sensitive they
are to changes in blood pressure. So extremely premature infants are at the
greatest risk for intraventricular hemorrhage.
Regardless of an
infant's
gestational age at birth, the risk of intraventricular
hemorrhage drops significantly after the first 72 hours of life and is
negligible after 7 days of age. Very premature infants typically have an
ultrasound of the head (cranial ultrasound) 3 to 7
days after birth to check for intraventricular hemorrhage. Those who show signs
of bleeding are periodically checked thereafter.
Prevention
measures that can reduce the risk of intraventricular hemorrhage
include:1
- Corticosteroid treatment, given to the
mother before the birth. This treatment is typically given to help fetal lungs
develop before a premature birth and is thought to make blood vessels less
likely to bleed.
- Indomethacin, given to the infant after birth.
This
nonsteroidal anti-inflammatory drug (NSAID) tightens
the brain's blood vessels (vasoconstriction), which helps control sudden
changes in blood pressure in the brain.