Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

AP Summer > Anesthesia for Opthalmic Surgery > Flashcards

Anesthesia for Opthalmic Surgery Flashcards

1
Q

What nerves does a retrobulbar block inhibit?

A

CN 2, CN 3, CN 4, CN 5, CN 6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the only muscle missed when doing a retrobulbar block?

A

Superior Oblique muscle

This is seen in the isolated 4th nerve function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What nerve must also be blocked to ensure total anesthesia for eye surgery when doing a retrobulbar block?

A 
CN 7
(this nerve is what allows you to squint your eye)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What in the eyeball acts as a shock absorber and protectant of the eye?

A

Orbital fat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How many “pops” do you feel when placing needle for retrobulbar block?

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the two pops of a retrobulbar block with the needle?

A

: piercing of skin

: Piercing orbital septum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

When your patient becomes unconscious and stops breathing approx 5-7 min after placing a retrobulbar block, what has occurred?

A

Subarachnoid brainstem anesthetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What has occurred when a subarachnoid brainstem anesthetic presents?

A

Local anesthetic has entered the subarachnoid space and entered CSF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where does the LA enter the CSF (how is it able to enter CSF) during a retrobulbar block?

A

At the spatium intervaginale. Is entrance of optic nerve at back of eyeball that brings a sheath of dura into eyeball thus allowing direct pathway to CSF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the muscles of the eyeball?

talk about right eye

A 
Lateral side:  Lateral rectus
Bottom: Inferior rectus
Top: Superior Rectus
Medial: Rectus medialis
Obliques: Superior and Inferior obliques
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Presbyopia tends to start to onset during what stage in life?

A

5th decade

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is presbyopia?

A

When the cillary body tenses but lens does not follow suit and flatten out, causing lack of near sightedness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where is the aqueous humor of the eye made?

A

Cillary bodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How many chambers are there in the human eye, and what separates them?

A

2 chambers , Posterior and anterior

Separated by Iris

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the plastic like bag that is filled with jello?

A

Lens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

When the cillary bodies relax, which part of eyesight is seen?

A

Far sight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

When the cillary bodies tense, what eyesight is seen?

A

Near sight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is known as an increase in intraocular and is treated when pressure becomes greater than 25 mmHg?

A

Glaucoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is one the leading causes of cataract?

A

Diabetes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is cataract?

A

Clouding of the lens of the eye that results in vision being distorted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What dilating drops are used in opthalmic surgery?

A

10% phenylephrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the concentration of 1 drop of 10% phenylephrine?

A

7mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Systemic absorption of opthalmic drops occurs through what mechanism?

A

Through the tear duct system and drainage into/through nose (which is highly vascular)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are 3 determinants for intraocular pressure?

A
  • Extrinsic pressure
  • Scleral rigidity
  • Alteration of eye contents
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What happens when pressure rises in the eye high enough to cause bleeding into eye that displaces the retina?

A

Expulsive hemorrhage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Expulsive hemorrhage causes loss of vision and loss of eyeball, what are some causes of this?

A
  • Coughing on tube

- Bucking on tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the most important determinants of intraocular pressure?

A

Rate of formation and drainage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are some things that increase intraocular pressure?

A
  • Acute hypertension
  • Hypoxia
  • Succinylcholine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are some things that decrease intraocular pressure?

A
  • Inhalation anesthetics

- Non depolarizing NM blockers

30
Q

What controls the afferent signal of the oculocardiac reflex?

A

Trigeminal nerve

31
Q

What controls the efferent signal of the oculocardiac reflex?

A

Vagus

32
Q

The oculocardiac reflex is seen most on which extra ocular muscle?

A

Medial rectus

33
Q

What are some causes of oculocardiac reflex?

A
  • Pressure on the globe
  • Ocular trauma
  • Traction on Extra ocular muscles
34
Q

What is the main bad outcome of the oculocardiac reflex?

A

Bradycardia

35
Q

Cataracts can be done by which type of anesthesia?

A

Local or general anesthesia

36
Q

What is one main concern from cataract surgery?

A

Expulsive hemorrhage

37
Q

When doing strabismus surgery, what drug do you have to stay away from?

A

Succinylcholine

38
Q

What is at very high risk when performing strabismus surgery?

A

M-H susceptible patients

39
Q

During strabismus surgery, an oculo-gastric reflex sometimes occurs, what is this?

A

Vagal mediated onset of PONV that cannot be fixed/cured by drugs

40
Q

When doing a glaucoma patient, what is the most important parameter to control?

A

Strict control of intraocular pressure

41
Q

Is there a risk of having eye surgery if your patient has had a prior MI?

A

NO risk at all

42
Q

During a retinal detachment surgery, what gas is used to press retina against the outer wall of the eye?

A

Sodium Hexaflouride

43
Q

Eye injuries represent how much percent of the ASA closed claims database?

A

3%

44
Q

Of the eye injuries reported, what was the most common injury?

A

Corneal abrasion

45
Q

Are corneal abrasion injuries permanent?

A

NO

46
Q

What is the second leading cause of eye injuries but is the most detrimental to patient safety?

A

Patient movement

always results in blindness

47
Q

Does patient movement have a higher incidence during general surgery or MAC cases?

A

General surgery

48
Q

So when doing general anesthesia for eye surgery, the patient should be deeply anesthetized and paralyzed , T OR F?

A

TRUE

49
Q

Who is the father of Local Anesthetics?

A

Carl Kholar

50
Q

What did Kholar first use as LA on patients?

A

Cocaine

51
Q

What was Dr. Morrow’s choice of LA?

A

4 mL of 0.75% marcaine
4 mL of 2% Lidocaine
1 mL of Hyaluronidase 200 units/mL

52
Q

What is the best needle to use for eye blocks?

A

Single bevel needle that is flat ground

53
Q

Why are eye block needle flat ground?

A

To feel tactile sensation needed to be precise

54
Q

What are eye block needles called?

A

Atkinson needles

FLGR

55
Q

What block is similar to a spinal because of its low volume and rapid onset?

A

Retrobulbar block

56
Q

What are some disadvantages of a retrobulbar block?

A
  • -Hematoma
  • -Brainstem anesthetic
  • -Perforation of globe
  • -Oculocardiac reflex
57
Q

Explain how to place a needle for retrobulbar block.

A
    • SOMEONE INSERT NAME OF LOCATION WHERE NEEDLE GOES
    • Feel skin pop, feel orbital setpum pop
    • Tilt needle inferior, advance catheter further
    • Place 4 mL of LA at back of orbit
    • Place 1 mL of LA on way out
58
Q

The facial nerve block that occurs near the first division of the facial nerve near the tragus and TMJ

A

Nadbath

59
Q

The facial nerve block that occurs near the superior portion of the eye (supra orbital)?

A

Van Lint

60
Q

Which eye block is similar to an epidural because takes large volumes, longer onset of action, and requires frequent supplementation?

A

Peribulbar block

61
Q

What are the advantages to a peribulbar block?

A
    • Avoids injection into muscle cone
    • Avoids need for facial nerve block
    • Lowers risk of globe perforation
62
Q

Explain how to do the peribulbar block?

A
    • 1 injection on top part of eye and 1 injection of bottom side of eye, on either side of the midline
    • Walk the wall of the orbit until reaching adequate depth
    • Inject 4 mL on top
    • Inject 4 mL on bottom
63
Q

How long must you wait to check for peribulbar blocks to take effect?

A

10 min

64
Q

What must you use for 20 min after placing a peribulbar block?

A

Ocular compression device to prevent increases in intraocular pressure

65
Q

What are the 2 main indications for a peribulbar block/

A
    • Long axial eye length

- - Previous extra-ocular surgery

66
Q

What is a normal axial eye length?

A

20-22 mm

67
Q

A high myope has what characteristics?

A
    • Very nearsighted
    • Long axial length
    • requires spherical correction of < -5.00 D
68
Q

What is the maximum axial length that you can perform a retrobulbar block?

A

26 mm

Anything longer requires peribulbar block

69
Q

The first set of numbers when reading a ophthalmologist diagnosis states what?

A

Spherical correction

    • Positive numbers corrects far sightedness
    • Negative numbers corrects near sightedness
70
Q

The second set of numbers when reading a ophthalmologist diagnosis states what?

A

Cylindrical corrections

– Corrects for stigmatism’s

71
Q

The last number when reading a ophthalmologist diagnosis states what?

A

Bifocal corrections

– Correct up close vision

AP Summer (24 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions