Neuro Flashcards by Rachel Oakman

Two principal cell types in nervous system?

Neurons

Supporting cell

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Excitable cells that transmit electrical signals

Neurons

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Cells that surround and wrap neurons

Supporting cells

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Function of supporting cells (neuralgia or glial cell) (4 things)

Provide a supportive scaffolding for neurons
Segregate and insulate neurons
guide young neurons to the proper connections
Promote health and growth of neurons

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Supporting cells include?

Astrocytes
Microglia
Ependymal cells
Oligodendrocytes

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Most abundant, versatile, and highly branched shaped like a star, glial cell

Astrocytes

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They cling to neurons and their synaptic endings and cover capillaries (BBB)

Astrocytes

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Most common brain tumor

Astrocytoma

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Astrocyte functions (4)

Support and brace neurons
Anchor neurons to their nutrient supplies
Guide migration young neurons
Control the chemical environment

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Two types of mircoglia

Macrophage (pacman) of vns

Phagocytes thar monitor health of neurons

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Small, ovoid cells with spiny processes

Microglia

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Range in shape from squamous to columar

Ependymal cells

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Ependymal cells range in shape from _______ to ______?

Squamous to Columnar

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Line the central cavities of the brain and spinal column

Ependymal cells

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Secrete csf (along with choroid plexus)

Ependymal cells

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Have cilia which help circulation of CSF

Ependymal cells

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Branched cells that wrap cns nerve fibers

Oligodendrocytes

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Forms myelin sheath in CNS which wrap around a on and provide insulaton

Oligodendrocytes

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Forms myelin sheath in peripheral nervous system

Schwan’s cells

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Surround neuron cell bodies with ganglia

Satellite cells

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3 structures of blood brain barrier

1 exceptionally tight junctions between brain capillary endothelial cells
2 basement membrane
3 astrocyte processes

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Barrier between cerebral capillaries blood and csf

Blood brain 🧠 barrier

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Csf fills

Ventricles and subarachnoid space

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Consists of the endothelial cells of the cerebral capillaries and the choroid plexus epithelium

Blood brain barrier

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_____________ in cerebral blood vessels are joined together by exceptionally "tight" junctions and are nearly fused.

Endothelial cells

Lack of pores makes

Blood brain barrier

_________ and _________ can cross over (bbb) by carrier-mediates transport mechanism.

Glucose and amino acid

Can cross bbb

Co2, o2, anesthetics | Non polar lipid soluble cam cross more readily

Cannot cross bbb

Most ions, proteins, large substances (like mannitol) | Watee moves freely across bbb as a consequence of bulk flow

Bbb can be disrupted by

``` Htn Tumors Trauma Stroke Infection Hypercapnia Hypoxia Seizures ```

Ares that don't have bbb

Vomiting center | Osmotic center in hypothalamus

Infarction destroys bbb leading to

Vasotec edema

Bile crosses under developed bbb in Newborn

Kernicterus

The brain is protected by _______, ________, and ________?

Bone, meninges, cerebrospinal fluid

Three connective tissue membranes lie external to the cns

Dura mater Arachnoid mater Pia mater

Functions of the meninges? (4)

Cover and protect the cns Protect blood vessels and enclose venous sinuses Contain cerebrospinal fluid Form partitions within the skull

Leathery, strong meninx composed of 2 fibrous connective tissue layers

Dura mater

Dura mater 2 layers separate in certain areas and form _______?

Dural sinuses

3 dural septa extend inward and limit excessive movement of the brain

Falx cerebri Falx cerebelli Tentorium cerebelli

Fold that dips into longitudinal fissure

Falx cerebri

Runs along the vermis of the cerebellum

Falx cerebelli

Horizontal dural fold extends into the transverse fissure

Tentorium

The middle meninx which forms loose brain coverings

Arachnoid mater

Separated from dura mater by subdural space

Arachnoid mater

Beneath the Arachnoid is a wide subarachnoid space filled with _______ and _______?

Csf and large blood vessels

______________ protrude superiorly and permit csf to be absorbed into venous blood.

Arachnoid villi

Deep meninx composed of delicate connective tissue that clings tightly to the brain

Pia mater

Cranial nerve I

Olfactory

Cranial nerve II

Optic

Cranial nerve III

Oculomotor

Cranial nerve IV

Trochlear

Cranial nerve V

Trigeminal

Cranial nerve VI

Abducens

Cranial nerve VII

Facial

Cranial nerve VIII

Vestibulocochlear

Cranial nerve IX

Glossopharyngeal

Cranial nerve X

Vagus

Cranial nerve XI

Assessory

Cranial nerve XII

Hypoglossal

Damage to the optic nerve

blindness

injury to the oculomotor nerve

strabismus, ptosis, loss of light reflex

trigeminal neuralgia " tic douloureux"

most severe face pain "suicide pain"

Nerves involved with trigeminal neuralgia

V and IX

Herpes simplex virus type 1 possible cause of which cranial nerve injury?

Bell's Palsy

Paralysis of VII facial nerve

Bell's Palsy

Damage of VIII nerve

Deafness

Damage to vagus nerve

hoarseness, loss of voice, impaired gut motility

Damage to XII

Tongue deviate to affected side

How may vertebra

How many cervical vertebrae

How many thoracic vertebrae

How many lumbar vertebrae

How many sacral (fused)

How many coccygeal

Join together by fibrocartilaginous intervertebral (IV) discs

Vertebral column

Typical vertebral consists of

body, vertebral, arch, seven processes, vertebral foreman, vertebral notches/ processes (7)

spinous (1), transverse (2), articular processes (4), connect adjacent vertebrae

vertebral notches/ processes

vertebral canal that houses the spinal cord

Vertebral foramen

for muscle attachment in the vertebra

seven processes

formed by pedicles and laminae

vertebral arch

Gray ramus has

post ganglionic neuron

White ramus has

pre-ganglionic neuron and sensory neuron

3 fates of preganglionic fibers

1. synapse in the paravertebral ganglia with the sympathetic postsynaptic neurons. Pass through gray rami (type C fibers) 2. ascend or decent in the paravertebral ganglia before synapsing with postganglionic neurons. 3. pass through the paravertebral ganglia without synapsing; these fibers synapse with postganglionic neurons in peripheral ganglia.

All sympathetic preganglionic fibers pass-through ________.

White rami

Some, but not all sympathetic postganglionic fibers pass-through _______

Gray rami

Gray rami are distributed to ______ spinal nerves

All

White rami are distributed to _____ spinal nerves

T1-L2

_________ allow coordinated, mass discharge of sympathetic nervous system.

Gray rami

Horner's syndrome lesion above ____

Horner s/s (6)

``` Ptosis (slight drooping of eyelids) anhidrosis (absence of sweating) miosis (pupil constriction) enophthalmos flushing (increased temp) nasal congestion ```

due to the destruction of the stellate (inferior cervical) ganglion. Loss of sympathetic tone and predominant parasympathetic tone

Horner's syndrome

Can occur after an Interscalene block

Horner's syndrome.

extends from foreman magnum ___ in adult and ___ in newborn.

L1 and L3

the spinal cord is ____ cm long

41-48

Cord terminates at ______________

CONUS medullaris (L2)

____ pairs of spin

nerve group in the lower dural sac ( L1-S5)

Cauda equina (horse tail)

Strong fibrous cord, sacrum to c7, thickest and broadest in the lumbar region

Supraspinous ligament

thin membranous ligament, thickest and broadest in lumbar region; the full length of the column

Interspinous ligament

Short segment between spinous processes

Ligamentum Flavum (yellow ligament)

outermost, tough, fibrous tube of fibers; runs longitudinally, extends from the foramen magnum to s2 vertebrae

Dura Mater

the middle layer, delicate, nonvascular, extends to s2

Arachnoid mater

innermost, delicate, microscopic, highly vascular. Directly covers the roots of the spinal nerves

Pia mater

widest at ___

narrowest at ___

___________ space lies between arachnoid mater and pia mater. CSF id found in this space.

Subarachnoid space

Blood supply to spinal and nerve roots comes from (2)

1. single anterior spinal artery | 2. paired posterior spinal arteries

CSF obtained from ______ between ___ and ___

lumber subarachnoid space, L4, L5

structures pierced as follows

skin---subcutaneous---supraspinous ligament---interspinous ligament---ligamentum flavum---epidural space---dura mater--subdural space---arachnoid mater---subarachnoid space---(CSF)

All ventral rami except ____-___ form interlacing nerve networks called plexuses

T2-T12

All ventral rami except T2- T12 form interlacing nerve networks called ________.

plexuses

Formed by C5-C8 and T1 (C4 and T2 may also contribute to this plexus)

Brachial Plexus

4 major branches of brachial plexus

Roots, Trunks, Divisions, Cords--Branches

2nd most common postop peripheral neuropathy

Brachial plexus

injured when arm abduction >90 degrees or improperly placed shoulder brace

Brachial plexus

innervates the deltoid and teres minor. injury inability abduct arm

Axillary

Sends fibers to the biceps brachii and brachialis; the most superior nerve of brachial plexus. inability to flex the forearm

Musculocutaneous

branches to most of the flexor muscles of wrist and fingers (opponents policies)

Median

pronation of foreman, flexion of the wrist, opposition of thumb, flexion of lateral three finger, injury ape hand "unable to oppose thumb."

Median

supplies the flexor carpi ulnaris and part of the flexor digitorum profundus

Ulnar

most common post up peripheral neuropathy. flexion of wrist, adduction of fingers, flexion of 2 fingers (4, 5) claw hand injury

Ulnar

innervates essentially ALL extensor muscles of arm and forearm

Radial

extension at elbow

radial

supination of forearm

Radial

extension of wrist and fingers

Radial

wrist drop injury

Radial

can be blocked to reduce pain from tourniquet inflation during IV regional anesthesia

intercostobrachial nerve

injury to superior trunk c5. c6

"klumpke paralysis"

injury to superior trunk c5. c6 in newborns

Erb-Duchenne palsy

injury to inferior trunk C8, T1

ulnar nerve damage, claw hand, grasp something during fall

Saturday night palsy "wrist drop"

radial nerve damage

paralysis of serratus anterior "winging scapula"

injury to long thoracic nerve

due to excessive probing in cubital fossa during venipuncture. "ape hand"

Median nerve damage

______ nerve (L4-L5 and S1-S3) originates from the lumbosacral trunk

Sciatic nerve

nerve damage caused by improper lithotomy position

Sciatic nerve

2 branches of the sciatic nerve

peroneal and tibial

branches of sciatic nerve, most frequent lower limb injury

Common peroneal nerve

2 nerve injuries that result in footdrop

Common peroneal nerve and tibial nerve

injured in a self-retaining refractor | absent knee reflex

Femoral nerve

Elevation, adduction, medial rotation of the eyeball

Superior rectus

Superior rectus innervation

Oculomotor III

Depression, adduction, medial rotation of the eyeball

Inferior rectus

Inferior rectus innervation

Oculomotor III

Adduction of the eyeball

Medial rectus

Abduction of eyeball

Lateral rectus

depression, abduction, medial rotation of eyeball

Superior oblique

Elevation, abduction, lateral rotation of eyeball

Inferior Oblique

Elevation of the upper eyelid

Levator palpebrae superioris

Levator palpebrae superioris innervation

Oculomotor III

Inferior Oblique innervation

Oculomotor III

Superior oblique innervation

Trochlear IV

Lateral rectus innervation

Abducent VI

Medial rectus innervation

Oculomotor III

Begins in the bifurcation of common carotid artery

Right and left internal carotid arteries

Right and left internal carotid arteries divides into (2)

Anterior cerebral artery and middle cerebral artery

lateral striate arteries; branches of middle cerebral arteries; supply internal capsule and motor tracts- arteries od stroke

middle cerebral artery

A single segmental branch of aorta. Major source of blood to the lower 2/3 of spinal cord. Can lead to paraplegia if clapped.

Artery of Adamkiewicz

Blood from cerebral and cerebellar cortex flows through ______________.

Dural Sinuses

Blood from basal portion of brain empties into ______________.

internal jugular vein

Circle of Willis. Blood enters through _______ and _______; main feeders of brain.

internal carotid and vertebral arteries.

is a posterior half of skull ‘cap’ (Dermatomes)

(Dermatomes) ___is a high turtle neck shirt

(Dermatomes) ___ is a low collar shirt – clavicle

(Dermatomes)___is at nipple

(Dermatomes)___is at the xiphoid process

(Dermatomes)___is at the umbilicus

T10

(Dermatomes)___is at the inguinal region

(Dermatomes)___include the tibia

L4, L5

(Dermatomes)___erection and sensation of penile and anal area

S2, S3, S4

Is associated with the detection and perception of noxious stimuli

nociception

The receptor for pain are ________ in the skin, muscle and viscera

free nerve endings

Neurotransmitters for nociceptors include ________Inhibition of the release of________ is the basis of pain relief by opioids

substance P.

Fast sharp pain is carried by________. It has a rapid onset and offset and is well localized

A-delta fibers

Slow chronic pain is carried by _______. It is characterized as aching, burning or throbbing that is poorly localized

C fibers

(Referred pain) Pain of visceral origin is referred to sites on the skin and follows the __________. These sites are innervated by nerve that arise from the same segment of spinal cord

dermatome rule

If the right lateral spinothalamic trace is severed at C3 what sensations are lost where?

Pain and temperature

What sensations are blocked in the lateral column by epidural or spinal anesthesia?

Pain and temperature

Pain sensations from genital organs are carried by _____________

autonomic nervous system

``` Free (naked) nerve endings Myelinated Diameter = 1-4  m Transmit fast/sharp pain (stinging, pricking) ; 6-30 m/sec Well localize , can point to pain ```

A- fibers

``` Free (naked) nerve endings Unmyelinated Diameter = 0.4-1.2  m Transmit slow/chronic pain ; 0.5-2 m/sec Diffuse , burning ,aching , throbbing sensation ```

C fibers

Cell bodies of A- and C fibers lies in _________.

dorsal root ganglia (DRG)

Fibers ascend or descend 1-3 segments in __________.

track of Lissauer

Pathway for fast sharp pain: After leaving tract of Lissauer, A- fibers terminated____________ of dorsal horn and cross to the contralateral ____________and ascend to the brain.

Lamina I and V, lateral spinothalamic tract

Pathway for slow chronic pain: C fibers terminates in __________. Interneuron transmit C fibers impulses to Lamina V from Lamina II and III. Neurons leaving Lamina V cross immediately to the ___________ and ascend to brain.

Lamina II and Lamina III (Substantia Gelatinosa ), contralateral lateral spinothalamic tract

A-  fiber; the neurotransmitter is ________which binds to ______ and _______receptors on the postsynaptic membrane.

glutamate, AMPA, NMDA

C fibers; the neurotransmitter is ______ which binds to __________receptor on the postsynaptic membrane.

substance P, NK-1(neurokinin-1)

_________ increase the synthesis of prostaglandins, kinins, thromboxane etc.

NK-1 receptors

Pain and temperature from the genitalia are mediated by _________.

autonomic nervous system

The _________ : Site where pains are attenuated (weaken)

Substantia Gelatinosa

C fibers terminates in _______, synapse with interneuron and secrete _______  PAIN

the substantia gelatinosa( Lamina II & III), substance P

Interneurons release _________.

Enkephalin

Enkephalin acts on opioid receptors (mu, keppa, delta) causing

Decrease Ca++ entry | Increase K+ out flux =hyperpolarization

Brain Control of Substantia gelatinosa | Descending neurons form ________ and ___________ terminates on enkephalin-releasing interneuron in substantia gelatinosa

periventricular, | periaqueductal gray matter

The interneuron release ________

enkephalin

Enkephalin inhibits release of _________

Enkephalin inhibits release of substance P

decreased number of pain impulses in the _______ -- spinal analgesia*

ascending lateral spinothalamic tract

Dorsolateral tract modulates pain by hyperpolarizing __________.

second order neurons

Acupuncture releases _________

endorphins

Neurotransmitters in descending pain modulation pathway-

Enkephalin GABA Nor epi Serotonin (5-HT) stimulates interneurons to release of enkephalin

The capsaicin receptor is a heat ________, which normally opens between 37 ° and 45 °C; hence, when capsaicin binds to its receptor, a sensation of heat is felt.

activated calcium channel

__________(relief of pain without loss of consciousness ) - Mainly -2 receptor

Spinal analgesia

(Neuraxial) Morphine, a hydrophilic opioid, crosses lipid membrane _______.

slowly

Intrathecal (Spinal) morphine | Slow onset and _____duration of analgesia

long

Intrathecal (Spinal) morphine. | No ________ depression of ventilation because uptake by systemic circulation is minimal

early

Intrathecal (Spinal) morphine. | _________ depression of ventilation occur due to rostral (towards head) spread of morphine in CSF

Late (6-12 hrs)

(Epidural morphine) Slow onset and ______duration of analgesia

long

(Epidural morphine) | ________depression of ventilation (within __ hrs) due to  uptake by systemic circulation (rapid transportation)

Early, 2 ,

(Epidural morphine) | ______ depression of ventilation occur due to rostral spread in CSF

Late

fentanyl, alfentanil, sufentanil –readily diffuse through____________.

lipid membrane

(lipid soluble spinal)______ diffusion out of CSF

Rapid

(lipid soluble spinal/ epidural)Rapid onset and _____duration of analgesia

short

(lipid soluble spinal/ epidural) _______depression (within _ hrs) of ventilation due to significant uptake by systemic circulation

Early, 2

(lipid soluble spinal/ epidural) Due to rapid diffusion out of CSF, little left in CSF for rostral spread, therefore, ______ depression of ventilation does NOT occur

late

(Spinal Analgesia) Occurs when transmission of pain through _______is suppressed after epidural or spinal administration

SG (L II)

(Spinal Analgesia) Mediated by Mu-1, Mu-2, kappa and delta. _____is the dominant receptor.

Mu-2

(Spinal Analgesia) After IV administration, opioid acts on _______and ________, _____, _______− spinal analgesia (don’t call this supraspinal analgesia)

periventricular, eriaquaductal gray, locus ceruleus, raphe magnus

(Supraspinal Analgesia) | Opioids act on_________ , and _______ and _______.

limbic system, hypothalamus, thalamus

(Supraspinal Analgesia) Mediated by Mu-1, kappa and delta. _____ is the dominant receptor.

Mu-1

Mu 1 (8)

Supraspinal and spinal analgesia Euphoria Low abuse potential Meiosis (PPP) Bradycardia Hypothermia Urinary retention-C/I in BPH Pruritus

Mu-2 (5)

Spinal analgesia Respiratory depression(decrease sensitivity of resp. center to CO2) Addiction Constipation (marked) decreased motility and tone of GI muscles increased CSF pressure (cerebral edema) C/I in head injury

Kappa (4)

Supraspinal and spinal analgesia Dysphoria, sedation Low abuse Potential Diuresis

Delta (4)

Supraspinal and spinal analgesia Respiratory depression Physical dependence Constipation (minimal)

(Posterior Fossa surgery) Paradoxical________ through existing ‘hole’ in heart (PFO)

air embolism

Monitor air bubbles with __________ (most sensitive), droppler, end-tidal CO2)

Esophageal Echocardiography

Treatment Notify the surgeon , so that surgical field can be flooded with N/S. Packing and bone wax, JV compression Discontinue nitrous oxide, give 100% O2 Aspiration with multi- orificed catheter placing tip ________ Aspiration with single- orificed catheter _________ Left lateral position, 15 head down IV fluid to increase CVP Vasopressor

2 cm below the SVC – atrial (cavoatrial) junction. | placing tip 3 cm above the SVC – atrial junction

(venous air embolism) Due to negative pressure in open _____ and _______.

veins, dural sinuses (-10 mmHg)

``` Monitoring VAE ________ – most sensitive non-invasive PA catheter ETCO2 ETN2 _______ – most sensitive ```

Doppler, Transesphageal echo (TEE)

Prevention of VAE Proper positioning Use of _______ Avoid ____

bone wax, N2O

Total volume of CSF = ___. Brain floats in ____.

150 ml, CSF

Specific gravity 1.002 – 1.009 ; pH ___

7.32

Pressure ____ mmHg

5-15

Formation of CSF by the _______ epithelium and ependymal cells = ______

choroid plexus, 500 ml/day @ 30 ml/hr

CSF Absorb through ________ (Brain and spinal cord have no lymphatic system)

Arachinoidal villi

CSF can be sampled with a ____________.

Lumber Puncture (L3-L4).

CSF pressure INCREASE in brain tumor, hemorrhage or infection-

________Papilledema

Local anesthetic e.g. Lidocaine , Bupivacaine are injected in subarachnoid space , mix with CSF results spinal anesthesia or ____________

subarachnoid block

CSF > Blood

Mg++ | Creatinine

CSF< Blood

``` K+ Ca++ Glucose Cholesterol* Protein* ```

CSF=Blood

Na+ Cl- HCO3- Osmolarity

(Hydrocephalus) dysfunction of CSF absorption

Communicating

(Hydrocephalus) | obstruction of ventricular system

Non-communicating

(Hydrocephalus) presentation

``` Irritability Increased head circumference Lethargy Vomiting Sun downing (can’t look up) ```

It is the cerebral oxygen consumption-CMRO2

CEREBRAL METABOLIC RATE (CMR)

Brain consumes ____ of total body O2

20%

Due to consumption ________and _______ reserves, interruption of cerebral perfusion results unconsciousness within 10 sec.

increased ,decreased

_____ is primary source of energy. During starvation, ______ are alternative source

Glucose, ketones

Glucose supply to brain is not_____ dependent

insulin

Cerebral Blood flow Average : _____g/min (~ 750-900 ml/min)

50 ml/100

Factors affecting CBF

PCO2 -major regulator H+ PO2 Sympathetic or parasympathetic play little or no role

H+ ions causes ___________ of cerebral blood vessels

VASODILATATION

Hypoxia causes __________  increased CBF

VASODILATATION

PO2 <20mmHg causes diminished neuronal activity or _____.

COMA

REGULATION OF CBF | 3

``` Cerebral Perfusion Pressure (CPP) Autoregulation Extrinsic Mechanism Respiratory gas tension Temperature Viscosity Autonomic influence ```

Cerebral Perfusion Pressure (CPP), Regulated by two forces

Mean arterial pressure | Intracranial pressure

pushing the blood into the brain

Mean arterial pressure

keeps the blood out

Intracranial pressure

CPP =

MAP- ICP (or CVP, whichever is greater)

Normally CPP

100 mmHg

CPP< 25 mmHg =

irreversible brain damage, flat EEG

DECREASED in CPP

VASODILATION

INCREASED IN CPP

VASOCONSTRICTION

Tissue metabolites (Nitric oxide (NO), adenosine,PGs) are responsible for _________.

vasodilation

>160 mmHg (MAP)

disrupt BBB, cerebral edema and hemorrhage occur

< 60 mmHg (MAP)

cerebral ischemia

CBF is directly proportional to _____between 20-80 mmHg

PCO2

1. Agents which increase CBF

Volatile anesthetics- halothane, isoflurane, enflurane

_________is the only I/V anesthetic that dilates the cerebral vessels and increase CBF (and ICP)

Ketamine

Agents which decrease CBF

I/ V anesthetics (thiopental) propofol, benzodiazepines and etomidate .

Cushing’s Triad

Irregular respiration, bradycardia, hypertension (increase systolic)

indications for icp montioring

``` Indications Trauma Subarachnoid hemorrhage Glasgow coma score < 7 Hydocephalus Pseudo tumor cerebri AV malformation ```

reduce icp

``` REDUCE ICP by Fluid restriction Corticosteroid Hyperventilation Thiopental for induction Avoid Ketamine Head-up position Diuretics CSF drainage Avoid PEEP Hypothermia ```

When a vasodilator such as nitroprusside is administrated , or when the patient is hypoventilated so that CO2 accumulates, vessel in non-ischemic brain dilate, flow to non-ischemic brain increase , and flow to ischemic brain decrease

Cerebral Steal (Luxury Perfusion)

When a patient with an ischemic region of brain is hyperventilated (decrease PCO2), blood vessels in non-ischemic brain constrict and blood is diverted to ischemic brain

Inverse Steal (Robin Hood Effect)

``` Most common 1 brain tumor Grave prognosis < 1 year life expectancy Found in cerebral hemisphere Resection, radiation and chemo ```

Astrocytoma

Relatively rare Slow growing (tumor)

oligodendroglioma

Found in 4th ventricle Can cause hydrocephalus Poor prognosis

ependymoma

2nd most common 1 brain tumor Occurs in convexities of brain and parasigittal region Arise from arachnoid cells external to brain (NOT dura) Slow growing Resectable

meningioma

Most commonly prolactinoma Bitemporal hemianopia “ tunnel vision” Hyper or hypo pituitarism are sequelae

Pituitary adenoma

3rd most common 1 brain tumor. Schwann cell origin; often localize to VIII nerve  acoustic schwannoma Resectable

Schwannoma

neurologic degenerative diseases that can be transmitted within or between species

Transmissible spongiform ecephalopathies (TSEs) | Mad Cow

The human form of TSE is called variant _________.

CJD (Creutzfeldt-Jakob disease)

______seizures arise from discrete region, no loss of consciousness

Focal (partial)

Treatment focal seizure

Phenytoin | Carbamazepine

Sustain seizure activity lasting at least 30 min | Medical emergency due to risk of hypoxia, aspiration, rhabdomyolysis and multiple trauma

Status epilepticus

Status epilepticus treatment

``` Treatment Establish airways “ABC” Adequate oxygenation Glucose +thyiamine Lorazepam – short term control Phenytoin or phenobarbital ```

(Guillain-Berré syndrome) _________ and _________ of PNS motor neurons

inflammation and demyelination

(Guillain-Berré syndrome) _________ motor neuron lesions

lower

(Guillain-Berré syndrome) dx

increase CSF proteins | Slow nerve conduction velocity.

Guillain-Berré syndrome treatment

Monitoring vital capacity is critical Plasmapheresis IV immunoglobulin

Symmetrical _______ paralysis (Guillain-Berré syndrome

ascending

LMN lesion due to destruction of anterior horn cell  flaccid paralysis

Poliomyelitis

mostly white matter demyelination; scanning speech, intentional tremors, diplopia, remission and relapses

Multiple sclerosis

Both UMN and LMN lesion. No sensory deficit

Amyotrophic lateral sclerosis

spares dorsal column | spinal cord lesion

Occlusion of anterior spinal artery

degeneration of dorsal root and dorsal column tract; impaired proprioception and ataxia

Tabes dorsalis (3 degress syphilis)

damage to spinothalamic tract; loss of pain and temperature

Syringomyelia

demyelination dorsal column

VitB12 deficiency and Friedreich’s ataxia

Most useful for assessment of cerebral perfusion

EEG

Most anesthetic produce ________pattern on EEG ________ followed by __________

biphasic. Activation, depression

Opioids produce _______ depression (EEG)

monophasic

Ketamine produces ________ activation (EEG)

unusual

Dorsal column tract is a _____ rout whereas RAS is an ______ for sensory information reaching to sensory strip

‘direct’, ‘indirect rout’

RAS is ____when sleeping

OFF

Complete loss of RAS activity is _____.

coma

GA produces sedation and hypnosis by ________RAS

depressing

Test the integrity of dorsal column (cuneatus and gracilis tracts) and sensory cortex

Somatosensory Evoked Potential –SSEP

Detection of global ischemia from _____ or _______, during brain and spinal cord surgery

hypoxia, anesthetic overdose

SSEP surgeries

Aortic reconstruction Spinal cord tumors Carotid endarterectomy Instrumentation of spine

_______ , _____ or _______ are stimulated and SSEP are recorded from the scalp

Tibial, median, or ulnar nerves

Stimulation of tibial nerve at ankle must be recorded at the ________

midline (over longitudinal fissure)

Stimulation of median/ulnar nerve must be recorded at ?

Lateral to midline

Action potentials via dorsal column tract

Early peak “direct”

Larger | Action potentials via reticular activating system (RAS)

Late peak “indirect”

Magnitude or size of evoked potential

Amplitude

Time taken by action potential to travel from peripheral nerve  spinal cord  inner brain  cerebral cortex

Latency

Applications of SSEP

Spinal surgeries Aortic reconstruction Carotid endarterectomy

Factors affecting SSEP

Hypo or hyperthermia Hypotension PCO2 PO2

Brain stem auditory evoked potential (BAEP) monitoring during brain surgery is a noninvasive technique for measuring neural functions, e.g. during acoustic neuroma resection where the _________at risk

vestibulocochlear nerve ( CN VIII)

VEPs can be used to monitor ________, ______visual pathways during craniofacial procedures, pituitary surgery, and surgery in the visual tracts and occipital cortex

the optic nerve (CN II), anterior

G.A. and volatile anesthetics have the greatest effect on evoke potentials causing dose dependent ______ amplitude and ________ latencies

decrease, increased

Order for sensitivity to anesthetic agents: Order for sensitivity to anesthetic agents: (evoked potentials)

VEP > SSEP > BAEP [ Very ; Somewhat ; Barely]

I/ V anesthetics have ________ effect on EP

fewer

has the least effect

Vecuronium

In general, intravenous anesthetics suppress motor evoke potential (MEP) responses much less than inhalational agents, so ______________ is preferred when MEPs are to be monitored in patients with neurologic disease.

total intravenous anesthesia

Neurocranium consists of 8 bones

``` Frontal Ethmoid Sphenoid Occipital Temporal (pair) Parietal (pair) ```

Viscerocranium consists of 15 irregular bones

``` Mandible Ethmoid Vomer Maxilla (pair) Inferior nasal choncha (pair) Zygomatic (pair) Palantine (pair) Nasal (pair) Lacrimal (pair) ```

Neuro Flashcards

(326 cards)