Neurological Alterations Pre-Recorded Lecture Flashcards
Pediatric Nervous System
Central Nervous System (brain and spinal cord)
Peripheral Nervous System (pain and muscle control)
Autonomic nervous system (involuntary functions, heart ect)
Development of Neurological System
Rapid growth period
- 15-20 weeks of gestation (dramatic increase in the number of neurons, a really sensitive time for any kind of infection or injury that could cause brain damage. viruses especially)
- 30 weeks of gestation to 1 year of age (period of growth so again increased risk with viruses, hypoxia, or malnutrition)
- brain development continues after birth
- grey matter can be increased by proper stimulation in the first three years of life
Cerebral blood flow & O2 consumption is almost 2x that of adults -> reflects increased metabolic requirement consistent with G&D. resp rate is higher, O2 needs are higher, HR is higher
Brain and spinal cord are among 1st major organ systems to be recognized in embryo & one of last to finish significant development after birth
Brain growth achieved:
50% by 1 year
75% by 3 years
90% by 6 years
Other pediatric differences
- cephalocaudal development
- at birth the brain and head are 12% of entire body mass whereas adults are 2%
- sensory pathways develop first (sense and feel pain) then motor pathways - obvious from child’s developing motor ability
- this developing state of the young child’s cerebrum makes this a very sensitive period, but also a forgiving period
- children can develop new pathways to overcome a neurological injury in the brain depending on the extent of the injury
Meninges
Dura mater (two spaces within this dura mater) - tough, outer meningeal membrane and inner periosteum of cranial bones)
- epidural space
- subdural space (between dura mater and arachnoid)
Arachnoid membrane (middle meningeal layer, delicate, avascular, weblike structure that loosely surrounds brain. Within that is the subdural space which is a potential space that prevents adhesion of the two layers. Has small vessels in it that can rupture during trauma and cause subdural hemorrhage.
- subarachnoid space: filled wth CSF; acts as cushion for brain tissue
- Pia mater: contains arteries & veins that supply brain: innermost covering, transparent membrane that adheres closely to the outer surface of the brain; includes arteries and veins of the brain.
ICP
very small amounts of blood increase their intercranial pressure very significantly
Cerebellum
Brain Stem
Cerebellum: so important in motor development and movement and a major area of concern for some children with neurological disorders
Brain Stem: cranial nerves - motor & sensory neurons travel through brainstem to allow for relay of signals b/n brain & spinal column; coordinates motor control signals from brain to body; controls life-supporting autonomic functions of peripheral nervous system
Autoregulation of Cerebral Blood Flow
- intracranial pressure
- cerebral arteries change their diameter in response to fluctuating cerebral perfusion
- autoregulation is the brains protection of itself. it works to keep the pressure constant
- CPP (cerebral perfusion pressure) = MAP-ICP
- Brain gets the blood even in crisis
Oxygen
O2 needs alter with temperature
- increased temp = increased O2 needs
- decreased temp = decreased O2 needs
Sensitive to PaO2 and PaCO2 (ICP decreases with high CO2)
Blood brain barrier
- at birth is indiscriminate and allows passage of protein as well as oxygen and glucose
- children are more sensitive to medications
- a child, especially young child, is at a sensitive time
Neurological Assessment of Children - similar to adult, requires more observation and clinical data because children can’t communicate as well verbally
Behaviour
Cognitive status
Coordination and gait
Cranial nerves
Spinal nerves
Strength and power
Pupils - late sign
2 components of Level of Consciousness
Alertness and Cognitive power
Alertness
ability to react to stimuli
Cognitive power
ability to process & respond verbally or physically
Consciousness
implies awareness - ability to respond to sensory stimuli have subjective experiences
Unconsciousness
depressed cerebral function, or inability of brain to respond to stimuli