Flashcards in Hypoxia and Foetal Brain Damage Deck (6)
What causes localised capillary dilation in hypoxia?
- Falling oxygen
- Falling pH in tissues
- Rising carbon dioxide
- Rising lactic acid
What is unique about preterm babies?
- Capillaries are very fragile in the germinal layer around the ventricles
- Increased dilation of fragile capillaries = periventricular haemorrhage (rupture)
How does the nervous system play a part in attempted prevention of hypoxia?
- During hypoxic episodes, sympathetic and parasympathetic pathways attempt to compensate by stabilising HR and BP
- Episodes of bradycardia associated with sudden rises in BP
What effect does stress have on the foetus?
- Releases adrenaline
- BP increases
- This may cause rupture of small blood vessels
What happens as hypoxia increases?
- Bradycardia and low BP
- Cerebral ischaemia around the ventricles (brain cell death) which may lead to hemiplegia (paralysis of one side of the body)
- Tissue damage may cause blood clots
- Subarachnoid haemorrhage