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Neurology > Coma > Flashcards

Flashcards in Coma Deck (74)
1

What is consciousness?

Awareness of self and environment

2

What are the 2 types of alterations in consciousness?

-Arousal
-Cognitive and affective mental functioning

3

What is lethargy?

Motor slowness
Tired/sleepy, but easily aroused

4

What is stupor?

Unresponsiveness from which the patient can be aroused only be vigorous, often noxious stimuli

5

What are the two mechanisms of coma?

Hit both hemispheres or brainstem

6

What are the two major structural locations for a coma?

-Supratentorial
-Subtentorial

7

Where does arousability begin in the brain?

Pontine reticular activating system (reticular formation)

8

Where do the fibers from the RF go?

Decussate, and ascend into the thalamus, where they then project diffusely in the cortices

9

Where does the reticular activating system reside?

Posterior pons

10

Tumors in what location (generally) coma?

Pons (hitting the pontine reticular activating system)

11

True or false: stroke patients typically do not cause a LOC

True

12

Why are carotid artery doppler not useful for patient who lose consciousness?

Need to affect the pons to cause LOC, and carotids go to the cerebrum.

13

What does the anterior pons contain?

Motor neurons from the motor cortices

14

Locked-in syndrome is caused by a lesion where?

Anterior pons

15

What, generally, causes diffuse cortical involvement?

Toxins or diffuse problems

16

What are battle signs?

Postauricular ecchymosis 2/2 basilar skull fracture

17

What are Racoon eyes?

Periorbital ecchymoses 2/2 basilar skull fracture

18

Why is temp important with CNS s/sx?

Toxic

19

Which is more likely to cause a LOC: toxic or metabolic/infx problem or localized lesion

Toxic/metabolic/infx

20

What two parts of the neuro exam cannot be performed on a comatose pt?

Coordination and gait (obviously)

21

True or false: cerebral hemispheres are always unavailable with the neuro exam in comatose patients

True

22

What is the neuro exam focused on with a comatose patient?

Assess brainstem

23

What is the max score on a Glasgow coma scale? What is the lowest?

15
3

24

What are the three categories of the glasgow coma scale?

-Eye opening
-Verbal response
-Motor response

25

What parts of the brain control breathing?

Brainstem and forebrain

26

What are Cheyne-Stokes breathing?

Slow oscillation between hyper and hypoventilation

27

What is the one breathing pattern that does not result from a brainstem problem? What causes it?

Cheyne-stokes breathing

Hemispheric problems

28

What is a central neurogenic respiration?

rapid, continuous hyperventilation are more than 25

29

What, generally, causes Cheyne-stokes breathing pattern?

Metabolic, infectious

30

What is apneustic breathing?

Prolonged inspiratory gasp with pause at full respiration

31

What happens to breathing patterns with lesions that are progressively inferior in the brainstem?

Become more chaotic

32

What is cluster breathing?

Periodic-respiration of variable amplitude and frequency with variable pauses between clusters

33

What is ataxic breathing?

Breathing that is completely irregular in rate and rhythm

34

What is the main question being asked with comatose patients?

"Does the brainstem work?"

35

What are the four things that are assessed with brainstem exam?

-Resp
-Pupils
-EOMS
-Motor

36

What are thalamic pupils?

Small, but reactive

37

What are midbrain pupils?

Midposition and fixed

38

What are pontine pupils?

Pinpoint but reactive

39

What are uncal pupils?

Dilated, asymmetric and fixed (bad news)

40

What can uncal ("blown") pupils indicate?

Brain is herniating (impending death)

41

What are in the outer parts of CN III?

PNS fibers--thus motor is lost before pupillary response

42

What are usually the last thing to reveal an abnormality with a coma: respirations, Pupils, EOMs, or motor problems? What can alter this pattern?

Pupils

Toxic or other diffuse effects can cause pupil dysfunction

43

Normal eye motility implies integrity in what structure?

Brainstem vestibular nuclei at the postomedulary junction

44

Normal conjugate gaze in an alert patient may be disconjugate when?

Sleep or slight alteration in consciousness d/t unmasking of strabismus

45

Conjugate ocular motility comes from where?

Frontal eye field

46

Eyes that deviate downward spontaneously = lesion where?

Brainstem

47

Dysconjugate motility of the eyes = ?

Damage to the frontal eye fields

48

Upward deviating eyes in a comatose patient = ?

Non-localizing

49

Skewed eyes in a comatose patient = ?

Brainstem or cerebellar problem

50

What is the oculocephalic reflex, and what does it indicate in a comatose patient if intact?

Doll's eye reflex

Indicates that CN VIII is intact, and thus the brainstem is at least somewhat intact

51

What is the vestibulo-oculogyric reflex?

Caloric testing--cold water injected into the ear, to cause eyes to deviate toward the cold water, and away from warm water

52

What causes the Doll's eye reflex?

When Supranuclear influences on oculomotor nerves are removed, eye maintain fixation on a point in the distance when the head it turned, providing brainstem integrity

53

What is the COWS mnemonic, and when does it apply? Why?

Cold opposite
Warm Same

Applies only to awake pts, because the fast component of nystagmus is controlled by the hemispheres

54

How is nystagmus named?

Fast beat

55

What controls the fast beat of nystagmus?

The hemispheres

56

There is not fast component of nystagmus when?

In the comatose patient

57

Does the COWS mnemonic apply to the comatose patient?

NO-It is OPPOSITE

58

What is decorticate posturing? What does this indicate?

Bilateral flexion at the elbows and wrists with extension of the lower extremities

Lesion is above the brainstem

59

What is decerebrate posturing? What does this indicate?

Bilateral extension of the elbows with extension of the lower extremities

Usually bilateral or midbrain pontine

60

What is myoclonic jerking?

Non-rhythmic movement d/t metabolic causes

61

What is rhythmic myoclonus?

Brainstem issues

62

True or false: the plantar reflex may be extensor in coma for any reason

True

63

True or false:Most patients with absent cortical or brainstem function will have some form of spinal reflex

True

64

Which generally has a rapid, and which a slow onset: structural / metabolic causes of a coma?

Structural = rapid
Metabolic = slow

65

What are the respirations like with metabolic problems?

Deep, frequent

66

What are the three major non-structural causes of coma?

Toxins
Metabolic
Infectious

67

What are the PE signs of head trauma?

-Racoon eyes
-Battle signs
-Hemotympanum
-Rhinorrhea or otorrhea (with CSF)

68

Where is the major breathing center in the brain?

Medulla and Pons

69

What are the pupil characteristics of opioid use?

Pinpoint

70

What is the role of the vestibulo-oculogyric reflex testing?

Confirm or refute a negative Doll's eye maneuver

71

In the comatose patient, putting cold water in the right ear will cause the eyes to deviate what direction?

There is no fast nystagmus phase in the comatose patient, but the slow phase remains intact. Thus the COWS mnemonic is reversed, and the eye deviates TOWARD

72

Asymmetry with eye movements indicates a metabolic or structural problem?

Structural

73

What is the reversal agent for opioids?

Naloxone

74

What is the reversal agent for Benzos?

Flumazenil