Flashcards in Central Nervous System Issues Deck (81)
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?
Which ramus is primarily postganglionic?
______ 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.
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)
The medial rectus ________ the eye.
The lateral rectus ________ the eye.
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?
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
Ketamine causes a ______ in CBF and ______ in CMRO2.
increase in both due to stimulation of SNS
The major source of blood flow (75%) to the spinal cord is the _______ ________ ________ which traverses the length of the spinal cord.
anterior spinal artery; there is only 1 of them
The ______ ______ ______ supplies 25% blood flow to the posterior cord.
posterior spinal artery; there are 2 of them
The ____ ___ _______ enters the vertebral canal from the left side in the majority of patients (it is not bilateral) in the lower thoracic region or upper lumber region.
artery of Adamkiewicz (artery radicularis magna)
What is the significance of the artery of Adamkiewicz?
May be the MAJOR source of blood to the lower 2/3rds of the spinal cord.... interruption of flow through this vessel can lead to paraplegia