Central Nervous System Issues Flashcards
What is the correct order (from outwards in) of the spinal meninges?
DAP! Dura mater, arachnoid, pia mater
Afferent nerves are ________ and enter the spinal cord from the _______ side.
sensory; dorsal (posterior)
Efferent nerves are ______ and exit the spinal cord from the ______ side.
motor; ventral (anterior)
The spinal nerve root is connected to the _________ ______ ________ by communicating channels called the _____ and ______ rami communicans.
paravertebral sympathetic ganglia; white and gray
Which ramus is primarily preganglionic?
White
Which ramus is primarily postganglionic?
Gray
______ rami carry myelinated sympathetic ____-ganglionic neurons and _____ rami carry unmyelinated sympathetic ____-ganglionic neurons (C-fibers).
White; preganglionic; Gray; postganglionic
______ nerves to skeletal muscle arise from the anterior horn of the spinal cord.
Motor
What are the two divisions of the peripheral nervous system and their primary function?
somatic (motor nerves to skeletal muscle and sensory nerves for pain, touch, pressure, temperature) and the autonomic division (sympathetic and parasympathetic)
Where is the epidural space located in relation to the ligamentum flavum? (anterior, posterior, superior, inferior, or lateral)
anterior
The medial rectus ________ the eye.
Adducts
The lateral rectus ________ the eye.
Abducts
What nerve innervates the medial rectus muscle and causes the eye to adduct?
oculomotor nerve (III)
What nerve innervates the lateral rectus muscle and causes the eye to abduct?
abducens nerve (VI)
Where is the site of CSF formation?
choroid plexuses of lateral, third, and fourth ventricles
Where is the site of reabsorption for CSF?
arachnoid villi
Name the cerebrospinal circulation pathway.
choroid plexus–>lateral ventricles–>foramina of Munro–> third ventricle–> aqueduct of sylvius–> fourth ventricle—> then to the foramina of Lushka OR THE foramen of Magendie–> subarachnoid space of spinal cord–> brain—> arachnoid villi
What is the purpose of the circle of Willis?
permits collateral blood flow in the event that a major vessel (right or left carotid artery or basilar artery) becomes occluded
What major vessels supply the circle of Willis?
right and left internal carotid basilar artery (which is supplied by the right and left verterbral arteries)
What does stump pressure measure?
the pressure transmitted through the circle of willis back to the carotid artery for which endarterectomy is proposed; a good stump pressure indicates that the brain will be perfused adequately during the procedure
What is a normal or acceptable stump pressure?
> 60 mmHg is normal….. but they are frequently falsely low or falsely high
What effect does N2O ALONE have on CBF and CMRO2?
increases due to sympathomimetic activity
What effect does volatile anesthetics have on CMRO2 and CBF?
decrease CMRO2 and increase CBF
With the exception of _______, IV anesthetics ______ CMRO2 and _______ CBF.
except ketamine, all decrease both CMRO2 and CBF