Brain and Skull Flashcards
(26 cards)
Name the bones of the Cranium
- 22 Bones
- Frontal
- Occipital
- Parietal
- Temporal
- Sphenoid
What are the regions of the brain
- Cerebrum
- Cerebellum
- Diencephalon
Hypothalamus
Thalamus
Brain stem.
- Midbrain.
- Pons varolii.
- Medulla oblongata.
Definition of the Cerebrum
- Largest and most superior position of the brain
- Divided into two hemispheres
- Thin cerebral cortex is made up of Gyri (elevated folds) and sulk (shallow groves)
- Grey matter
- White matter
Lobes of the Cerebrum and there function
Parietal Lobe
- sensory area, Touch, pain, and temperature are interpretated
Temporal Lobe
- Auditory function, Olfactory
- Contains Wernicke area (understanding words)
Occipital Lobe
- Visual area
Frontal Lobe
- Conscious control, planning and conscious thought
- Contains the Broca’s area (motor speech to form words)
Definition of the Cerebellum
- Balance and standing
- Co ordinates skeletal muscle
- Regulates posture and balance
- May have a role in cognition and language processing
What does the Diencephalon contain
- Thalmus
- Hypothalmus
- Epithalmus
What does each part of the Diencephalon contain and its function
Thalmus
- Relays sensory input
Hypothalmus
- Maintains homeostatsis
- Produces Hormones (ADH)
- Controls body temperature
- Regulates sleep
- Heart Rate
Epithalmus
- Pineal gland secrets Melatonin
Define the Pons Varolli
- Bridge between the two hemispheres
- Contains the pneumotaxic and apneustic area
- Origin of some cranial nerves for the eye
Define the Medulla Oblongata
- About 2.5cm long
- Cardiovascular centre regulates the HR
- Central chemoreceptors monitor Ph of CSF and Blood CO2
- Areas tha influence vomitting, swallowing and coughing
Facts about CSF fluid
- Has oxygen carrying capability
- Provides mechanical protection
- Produces 20ml/hr CSF
- Glucose rich
- CSF is absorbed back into the blood stream at the Arachnoid Villi
What do Cerebral Ventricles do
- Maintains homeostasis through supplying nutrients to the brain
- CSF produced in the Choroid Plexus
- CSF can hold 80-150ml
- 4 Ventricules
Where is CSF produced and absorbed
- CSF produced in the Choroid Plexus
- CSF is absorbed back into the blood stream at the Arachnoid Villi
What is Normocapnia
- EtCo2 35-44mmHg (4,6Kpa)
What is Hypercarnia and what could it cause
- Hypoxemia
- Increase Co2
- Can cause Cerebro Vascular vasodilation
What is Hypocapnia and what could it cause
- Hyperventilation
- Decrease in CO2
- Cerebrovascular Vasoconstriction worsening cerebral hypoxia
What is the Blood brain barrier
- Blood supply to the brain 750m/min
- Consumes 20% of O2 and Glucose
- Vessels are surrounded by Astrocytes that are highly permiable to H2O, Glucose, Lipid soluable substances (O2, CO2, Alcohol, Anaesthetics)
Three componants of the CNS
- Brain tissue 80%
- Blood volume 10%
- CSF 10%
What is the Monroe Kelly Hypothesis for ICP
- Pressure volume relationship between brain/csf/blood
- Normal ICP 0-15mmHg
- Cranial Perfusion Pressure
CCF = MAP - ICP
(think about this with hyper/hypotensive patients)
What is the calculation for MAP
BP - 120/80
120 + (80x2) \ 3
= 120 + 160 = 280
280 / 3
MAP = 93.3
Normal Level for CCP
70-80
Calculation for CCP
CCF = MAP - ICP
CCF = 93 - 10
= 83
What are the thing to look for in Cushings Triade
ICP
- Increase Systolic BP
- Reduced Pulse
- Reduced Respirations
Shock
- Low BP
- Increase Pulse
- Increas Respirations
Point to remember about Head inj
- They will never have a Low BP
- Always have a high bp
What can raise ICP
- Position
- Positive Pressure Ventilation
- Application of C collar
- Restraining Patient
