chapter 41: neurosurgery Flashcards Preview

ABSITE. > chapter 41: neurosurgery > Flashcards

Flashcards in chapter 41: neurosurgery Deck (86):
1

come together to form a single basilar artery, which branches into 2 posterior cerebral arteries

vertebral arteries

2

connect middle cerebral arteries to posterior cerebral arteries

posterior communicating arteries

3

branches off middle cerebral arteries and are connected to each other thru the 1 anterior communicating artery

anterior cerebral arteries

4

no axonal injury (temporary loss of function, foot falls asleep)

neurapraxia

5

disruption of axon with preservation of axon sheath, will improve

axonotmesis

6

disruption of axon and axon sheath (whole nerve is disrupted), may need surgery for recovery

neurotmesis

7

how fast does regeneration of nerves occur?

1mm/day

8

nerves: bare sections; allows salutatory conduction

nodes of ranvier

9

what controls the release of antidiuretic hormone (ADH)?

release controlled by supraoptic nucleus of hypothalamus, which descends into the posterior pituitary gland

10

released in response to high plasma osmolarity; ADH increases water absorption in collecting ducts

antidiuretic hormone (ADH)

11

increased urine output
decreased urine specific gravity
increased serum Na
increased serum osmolarity

diabetes insipidus (decreased ADH)

12

two situations which can cause diabetes insipidus

ETOH, head injury

13

tx: diabetes insipidus

DDAVP, free water

14

decreased urine output
concentrated urine
decreased serum Na
decreased serum osmolarity
- can occur with head injury

SIADH (increased ADH)

15

Tx: SIADH

fluid restriction, then diuresis

16

50% present with hemorrhage; are congenital
- usually in patients

arteriovenous malformation

17

tx: arteriovenous malformation

resection if symptomatic
- can coil embolize these prior to resection

18

usually occur in patients > 40; most are congenital.
- can present with bleeding, mass effect, seizures, or infarcts

cerebral aneurysms

19

where do cerebral aneurysms most likely occur?

occur at branch points in artery, most off middle cerebral artery

20

tx: cerebral aneurysm

often place coils before clipping and resecting aneursym

21

cause by torn bridging veins

subdural hematoma

22

- has crescent shape on head CT and conforms to brain
- higher mortality than epidural hematoma

subdural hematoma

23

tx: subdural hematoma

operate for significant neurologic degeneration of mass effect (shift > 1cm)

24

caused by injury to middle meningeal artery
- has lens shape on heat CT and pushes brain away
- patients classically lose consciousness, have a lucid interval, and then lose consciousness again

epidural hematoma

25

tx: epidural hematoma

operate for significant neurologic degeneration or mass effect (shift > 0.5 cm)

26

caused by cerebral aneurysms (50% middle cerebral artery) and AVMs
- symptoms: stiff neck (nuchal rigidity), severe headache, photophobia, neurologic defects

subarachnoid hemorrhage (nontraumatic)

27

tx: subarachnoid hemorrhage (nontraumatic)

goal is to isolate the aneurysm from systemic circulation (clipping vascular supply), maximize cerebral perfusion to overcome vasospasm, and prevent rebleeding; use hypervolemia and CCB to overcome vasospasm

28

when do you go to OR for subarachnoid hemorrhage?

go to OR only if neurologically intact

29

lobe most often affected in intracerebral hematomas

temporal lobe most often affected

30

management: intracerebral hematomas

those that are large and cause focal deficits should be drained

31

symptoms of increased ICP

stupor, headache, nausea and vomiting, stiff neck

32

signs of increased ICP

hypertension, HR lability, slow respirations

33

sign of severely elevated ICP and impending herniation

intermittent bradycardia

34

hypertension
bradycardia
slow respiratory rate

Cushing's triad

35

tx: spinal cord injury with deficit

give high dose steroids (decreased swelling)

36

areflexia
flaccidity
anesthesia
autonomic paralysis below the level of the lesion

complete spinal cord transection

37

hypotension, normal or slow heart rate, and warm extremities (vasodilator)
- occurs with spinal cord injuries above T5 (loss of sympathetic tone)

spinal shock

38

tx: spinal shock

fluids initially, may need phenylephrine drip (alpha agonist)

39

mcc anterior spinal artery syndrome

most commonly occurs with acutely ruptured cervical disc

40

- bilateral loss of motor, pain, and temperature sensation below the level of lesion
- preservation of position-vibratory sensation and light touch

anterior spinal artery syndrome

41

rate of peeps that recover to ambulation with anterior spinal artery syndrome

about 10% recover to ambulation

42

incomplete cord transection (hemisection of cord); most commonly due to penetrating injury

brown-sequard syndrome

43

symptoms of brown-sequard syndrome

loss of ipsilateral motor and contralateral pain/temperature below level of lesion

44

rate of peeps that recover to ambulation with brown-sequard syndrome

about 90% recovery to ambulation

45

mcc central cord syndrome

most commonly occurs with hyperflexion of the cervical spine

46

bilateral loss motor, pain, and temperature sensation in upper extremities; lower extremities spared

central cord syndrome

47

pain and weakness in lower extremities due to compression of lumbar nerve roots

cauda equina syndrome

48

carries pain and temperature sensory neurons

spinothalamic tract

49

carries motor neurons

corticospinal tract
rubrospinal tract

50

are generally afferent; carry sensory fibers

dorsal nerve roots

51

are generally efferent; carry motor neuron fibers

ventral nerve roots

52

headache, seizures, progressive neurologic deficit, and persistent vomiting

brain tumors

53

where do most brain tumors present in adults?

adults: 2/3 supratentorial

54

where do most brain tumors present in children?

children: 2/3 infratentorial

55

most common primary brain tumor in adults and overall

gliomas

56

most common subtype of glioma, uniformly fatal

glioma multiforme

57

#1 metastasis to brain

lung

58

most common brain tumor in children

medulloblastoma

59

most common metastatic brain tumor in children

neuroblastoma

60

arises from the 8th cranial nerve at the cerebellopontine angle

acoustic neuroma

61

symptoms: hearing loss, unsteadiness, vertigo, nausea, and vomiting
- tx: surgery usual

acoustic neuroma

62

overal most are benign; #1 spine tumor overall

neurofibroma

63

spinal tumors: more likely benign

intradural tumors

64

spinal tumors: more likely malignant

extradural tumors

65

what do you check for with paraganglioma?

check for metanephrines in urine

66

what causes intraventricular hemorrhage (subependymal hemorrhage) in premature infants?

secondary to rupture of the fragile vessels in germinal matrix

67

risk factors for intraventricular hemorrhage in premature infants

ECMO, cyanotic congenital heart disease
- patients go on to get intraventricular hemorrhage

68

symptoms: bulging fontanelle, neurologic deficits, decreased BP and decreased Hct
- tx: ventricular catheter for drainage and prevention of hydrocephalus

intraventricular hemorrhage (subependymal hemorrhage)

69

- neural cord defect: herniation of spinal cord and nerve roots through defect in vertebra
- most commonly occurs in the lumbar region

myelomeningocele

70

speech comprehension, temporal lobe

Wernicke's area

71

speech motor, posterior part of anterior lobe

broca's lobe

72

dx/tx: pituitary adenoma, undergoing XRT, patient now in shock

dx: pituitary apoplexy
tx: steroids

73

cervical nerve roots innervating diaphragm

cervical nerve roots 3-5

74

acts as brain macrophages

microglial cells

75

CN1

olfactory - smell

76

CN2

optic - sight

77

CN3

oculomotor - motor to eye

78

CN4

trochlear - superior oblique (eye)

79

CN5

trigeminal: ophthalmic, maxillary, and mandibular branches
- sensory to face
- muscles of mastication

80

CN6

abducens
- taste to anterior 2/3 of tongue
- motor to face

81

CN7

facial
- taste to anterior 2/3 of tongue
- motor to face

82

CN8

vestibulocochlear
- hearing

83

CN9

glossopharyngeal
- taste to posterior 1/3 of tongue
- swallowing muscles

84

CN10

vagus
- many functions

85

CN 11

accessory
- trapezius, SCM

86

CN12

hypoglossal
- tongue