Neuroprotection from acute brain injury in prems Flashcards
Definition of acute brain injury?
Infarction caused by ischemia and/or hemorrhage caused by reperfusion within the cerebral ventricles or parenchyma
Why are premature infants at risk of acute brain injury?
They have a fragile cerebral vasculature and immature autoregulatory system - rapid changes in perfusion will cause ischemia or IVH
In Canada, approximately how many infants born =32+6 weeks GA show an abnormal cranial US?
21%
Which form of periventricular leukomalacia is becoming increasingly recognized due to MRI? Which form is in decline?
- noncystic PVL increasingly recognized
- Cycstic PVL declining
Abnormal brain images in the neonatal period are strongly associated with _______.
Neurodevelopmental impairment in the long term
What is the ‘critical window’?
The first 72h post birth - the highest risk period for acute brain injury
___% of IVH or parenchymal lesions are detected by ____.
95%, Day 5
There is a _____ incidence of chorioamnionitis and PPROM with decreasing gestational age.
Higher
Recommendation re: antibiotics for mother presenting with PPROM?
Administer penicillin and a macrolide (just macrolide if allergic to pen) if expected to deliver at =32+6
Neonate born at =32+6 with suspected or confirmed chorioamnionitis, PPROM, preterm labour, or unexplained onset of nonreassuring fetal status - what to do?
- Careful evaluation
- Blood culture
- Start empiric antibiotics, continue until blood cultures negative at 36-48h
Duration of ROM > ___ hours also an independent RF for IVH or intraparenchymal hemorrhage.
72h
How might corticosteroids protect against brain injury? What have antenatal corticosteroids been shown to do?
- They cause vasoconstriction in the fetal brain
- Reduce neonatal morbidity and mortality, including IVH
Corticosteroids reduce risk of brain injury when interval since last dose is greater than ___ hours compared to less than ___ hours before birth.
48
24
Recommendation re: administering corticosteroids? Optimal interval?
- Routinely within 7 days to all mothers expected to deliver a premature infant =34+6 weeks - and between 35+0 and 36+6 weeks in select clinical situations
- Optimal interval >48h between last dose administered and birth
Benefit of magnesium sulphate?
Decreases risk of CP