Midterm 2 Flashcards
1
Q
Biochemical properties of sodium fluorescein stain
A
- emits energy green wavelength when it comes down from its high energy state
- synthetic organic compound available as a dark orange water-soluble dye
2
Q
When is sodium fluorescein stain used?
A
- diagnostic agent in eyecare
3
Q
Factors that affect fluorescence of NaFl
A
- concentration (>2% will not glow)
- pH of solution (increased fluorescence with increased pH)
- intensity and wavelength of absorbed light
- maximum intensity obtained by use of cobalt blue filter over high intensity white light
- Wratten filter between blue light and our eyes maximizes the view of stained areas
4
Q
Does sodium fluorescein stain tissue?
A
No, it’s water soluble so it colors tears. Only stains tissues if overlying tissue is damaged (corneal ulcer)
5
Q
What is the molecular weight of regular sodium fluorescein stain?
A
367.27, which is smaller than pores in hydrogel lenses
6
Q
What is the molecular weight of high molecular weight fluorescein?
A
710, which may be used with SCL
7
Q
What is the mechanism by which sodium fluorescein stains the cornea?
A
- normal corneal epithelium is impermeable to tears and polar compounds like fluorescein
- corneal epithelial defects allow the tears (stained with fluorescein) to access deeper layers, and eventually can diffuse through hydrophilic stroma and into the AC
- epithelial defects “stain” bright green
- fluorescein will not stain devitalized (sick) cells
- can produce pseudo-flare, Fischer Schweitzer mosaic, when you put pressure on the closed lid to give the pattern
8
Q
Composition of fluorescein sodium
A
2%; 1, 2, 15 ml
9
Q
Composition of Fluress, which we don’t typically use if really assessing corneal health
A
0.25% with 0.4% benoxinate Hcl boric acid povidine 1% chlorobutonal; 5mL
10
Q
Composition of fluorocaine
A
0.25% with 0.5% proparacaine Hcl with thimerosal
11
Q
Composition of Proparacaine Fluorescein (B&L)
A
0.25% with 0.5% proparacaine Hcl
12
Q
Composition of Ful-Glo strips
A
0.6 mg sterile
13
Q
Composition of Fluor-I strip
A
9mg with buffers; 0.5% chlorobutonal polysorbate
14
Q
Composition of Fluor-I-strip-A.T.
A
1 mg with buffers; 0.5% chlorobutonal polysorbate
15
Q
Composition of Fluorets strips
A
1 mg
16
Q
Composition of Fluoresoft strips
A
0.35% in 0.5 mL pipettes
17
Q
Is sodium fluorescein at a greater risk of contamination than majority of other eye drops?
A
Yes, but not the case with combo anesthetic fluorescein
18
Q
Why is sodium fluorescein at serious risk of contamination?
A
It’s typically used in situations in which tissue is damaged
19
Q
What is the most dangerous and common contaminant in sodium fluorescein?
A
Pseudomonas aeruginosa
20
Q
What is the best preservative for NaFl?
A
Thimerosol
21
Q
What is the safest form of using sodium fluorescein?
A
sterile, single-dose units of solution OR sterile fluorescein-impregnated paper strips
22
Q
Clinical uses of topical fluoresceine dye (5)
A
- assessment of ocular surface integrity: detect defects in corneal epithelium
- fitting/assessment of rigid contact lenses
- applanation tonometry
- Seidel’s test (detection of globe perforation)
- testing the lacrimal system (tear film integrity, nasolacrimal system function)
23
Q
Does fluorescein penetrate an intact corneal epithelium?
A
No
24
Q
How does fluorescein staining take place with a break in the corneal epithelium?
A
- penetration of fluorescein in adjoining bowman’s and stromal layer
- dye makes contact with an alkaline interstitial fluid (stroma has higher pH)
- fluid turns bright green owing to its pH indicator properties and depending to extent of lesion
25
What other two purposes does fluorescein stain serve in optometry?
rigid contact lens assessment/fitting and Goldmann tonometry
26
What is Seidel's test/sign?
the aqueous coming out of a penetrating corneal laceration that appears dark in an overall green system
27
Can you use fluorescein for corneal and conjunctiva staining?
Yes
28
definition of epiphora
overflow of tears onto face
29
Where can tear drainage problems/obstructions occur?
- puncta
- canaliculus
- nasolacrimal duct
30
How to perform and grade Jones Test 1
- instill fluorescein; swab inside nose
- positive = presence of dye (no obstruction)
- negative = no presence of dye (partial or absolute obstruction OR poor tear pump)
31
How to perform and grade Jones Test 2
- done after negative Jones 1 test
- use syringe to flush residual fluorescein from lacrimal sac
- positive = dye recovered (partial obstruction aka functional obstruction)
- negative = no dye recovered (complete obstruction)
32
What is fluorescein angiography and why do we use it?
- invasive procedure in which sodium fluorescein is injected IV followed by serial fundus photography
- used to document retinal blood flow and integrity of blood vessels
- diagnostic tool in choroidal and retinal disease
33
Adverse reactions to FA
- nausea
- emesis
- urticaria
- syncope
- extravasation of dye
- anaphylaxis (1 in 300,000)
34
Procedure of FA
- take red-free pictures
- replace red-free filter with barrier filter
- inject fluorescein dye as a bolus
- start timer
- insert exciter filter
- begin shooting at first sign of choroidal flush
- shoot every 1-2 seconds during transition
- late photos as needed
35
Normal FA time frame
- choroidal phase (8-12 sec)
- retinal circulation - arterial, capillary, venous, recirculation phases
- elimination phase
36
What do you see during choroidal phase of FA?
"choroidal flush" with choroid beginning to fill - patchy dark retinal vessels
37
What do you see during retinal arterial phase (10-13 sec)?
fluorescein begins to fill the arteries, veins appear dark
38
What do you see during retinal capillary phase (12-15 sec)?
- arterioles are filled and beginning to see veins fill - bright sides and then fill
39
What do you see during retinal venous phase (13-17 sec)?
sometimes it's hard to tell because veins have slightly more brightness than arteries, but all blood vessels appear white
40
What do you see during retinal recirculation phase?
overall glow starts to diminish
41
What do you see during elimination phase of FA?
all sodium fluorescein out of retinal vessels but will see NaFl if blood vessels are broken
42
What is the yellow pigment that limits the amount of blue light that enters the macula?
Xanthophyll
43
What could cause pre-injection fluorescence? (Why we take pictures before injection)
optic disc drusen fluoresce with filter
44
What are some pathological reasons we would see hyper-fluorescence in FA?
- abnormal vessels from diabetes, choroidal neovascularization, and squiggly vessels from RVO
45
What are some reasons we would see hypofluorescence?
- blocking defect - there's fluorescein there, but we can't see it
- filling defect - blood vessels have issues with blood flowing through
46
Strategies for interpretation of FA
- look for pre-injection fluorescence to ensure no auto-/pseudo-fluorescence
- determine areas of hypo- and hyper- fluorescence
- if hypo-, is it due to blocking or delayed/absent filling?
- if hyper-, is it transmission defect, abnormal vessel, or leakage?
- match findings to specific disease process
47
Properties of rose bengal stain
- red/rose colored derivative of fluorescein but DOES NOT FLUORESCE
- water soluble red powder
- will stain cell membrane of dead (devitalized) cells - different from fluorescein
- TRUE histological stain that binds to selective cellular components
- also stains mucous and corneal filaments
48
Should you use anesthetic when using rose bengal?
Yes it stings and irritates the cornea
49
Indications to stain with rose bengal (3)
- toxic keratitis
- dry eye - classic conjunctiva and cornea staining
- herpes simplex dendritic keratitis
50
Properties of lissamine green stain
- vital stain very similar to rose bengal
- much more comfortable on instillation
- similar uses to rose bengal
51
When is trypan blue stain used?
- testing the health of endothelium in corneal grafts
| - used to stain the anterior lens capsule in certain cataract surgery cases
52
What is Indocyanine green stain and what can it be used for?
- water soluble tricarbocyanine dye
- rapidly and completely bound to plasma proteins after IV injection
- fluoresces in the infrared spectrum
- in eye care, can be used in fundus angiography
- can be used in retinal surgeries to identify the inner limiting membrane
contraindication: Iodine allergy
53
Is inflammation good in the cornea?
Not really, it can cause opacities with scarring
54
What does inflammation do in the body?
- destroys invading pathogen
- removes dead tissue
- replaces damaged tissue with scar tissue (fibrosis)
55
What do steroids do in eye care?
- control inflammation of anterior and posterior segments of the eye
- help prevent sequelae of inflammation on ocular structure
- typically used in ACUTE conditions
56
Pharmacology of corticosteroids: (how they affect the immune system)
Affect almost every aspect of the immune response
- inhibit neutrophil migration
- inhibit MQ access to inflammation site
- interfere with lymphocyte activity
- reduce number of T- and B- lymphocytes
- block histamine synthesis
- stabilize mast cells
- block arachidonic acid release
- influence tissue repair (decrease cap proliferation and decrease collagen deposition)
57
Indications for steroids in eye care
severe infections ONCE THE INFECTION HAS BEGUN TO RESOLVE and under carefully controlled situation
58
Can we use steroids in adenovirus eye disease?
Yes, it may prolong the infection, but the patient feels better
59
Can we use steroids in HSK epithelial disease?
NOOOOO!!!!!!!!
60
Can we use steroids in HSK stromal/disciform disease?
Yes, but with concurrent antiviral and they must be tapered VERY slowly
61
Can we use steroids with HZV?
Yes
62
Can we use steroids while treating bacterial eye disease?
Yes, staph organisms can produce secondary inflammation with exotoxins that can cause marginal ulcers and phlyctenules; must also address the underlying problem (can use combo gtts)
63
Can we use steroids to treat bacterial corneal ulcers?
- it depends
- for those with VA of CF or worse and those with central ulcers, adding a steroid to the Ab regimen showed a statistically significant improvement in prognosis
- otherwise may not be necessary
- no safety concerns
64
Can we use steroids in acanthamoeba and fungal keratitis?
NOOO!!!
65
What is the hallmark sign of acanthamoeba?
ring infiltrate
66
How to treat dermatologic manifestation of allergies around the eyes?
- triamcinolone 0.1% cream
- tell the patient to keep out of their eyes
- long-term steroid creams can thin the skin so be cognizant
67
What do corticosteroids do in uveitis treatment? (3)
- reduce inflammation
- help relieve pain (with cycloplegics)
- help prevent posterior synechiae
68
What type of steroid would we use to treat episcleritis (mild, moderate, heavy)?
Mild
69
What type of steroid would we use to treat scleritis?
- doesn't respond well to steroids
| - NSAID may be better
70
What other "-itis" conditions can we treat with steroids?
- pingueculitis
| - inflamed pterygium
71
How are steroids used in post-op care for cataract surgery?
- decreases risk of post-op cystoid macular degeneration (NSAIDs may be better)
- reduces inflammation and pain
- decreases corneal edema
72
How are steroids used in post-op care for refractive corneal surgery?
- reduces myopic regression and corneal haze (PRK)
73
ocular side effects of topical steroid therapy
- cataract
- ocular hypertension/glaucoma
- infection
- delayed corneal epithelial healing
74
Do posterior subcapsular cataracts occur more frequently with systemic or topical steroid use?
Systemic
75
Why are posterior subcapsular cataracts so visually debilitating?
they are near the nodal point and on the visual axis
76
How long does an adult have to be on a steroid before a PSC appears?
at least 1 year
77
Does steroid-induced glaucoma occur more frequently with topical or systemic steroid use?
Topical, but also common with nasally administered steroid
78
When does increased IOP occur after using a steroid?
usually occurs within 2-8 weeks of initiation of therapy
79
Is increased IOP secondary to steroid use reversible with drug cessation?
Yes, typically
80
Armaly and Becker study found what regarding steroid-induced glaucoma?
- steroid response is likely genetically determined
| - different steroids are more/less likely to cause elevated IOP
81
What steroid drops are more likely to cause elevated IOP?
- dexamethasone
- difluprednate
- prednisolone
82
What steroid drops are less likely to cause elevated IOP?
- loteprednol
- rimexolone
- fluorometholone
83
What is the mechanism that causes decreased IOP in uveitis?
ciliary body shuts down so less aqueous is produced
84
What is the mechanism that causes increased IOP in uveitis?
- trabeculitis (resistance to outflow)
- cellular debris clogs the TM
- posterior or anterior synechiae
85
Clinical pearls for prescribing steroids
- NEVER prescribe a steroid without measuring IOP first
- ALWAYS measure IOP on follow-up for patients on steroid
- NEVER allow refills of steroids unless IOP is routinely checked
86
Do patients with glaucoma tend to be steroid responders?
Yes
87
What are complications of steroid use with infection? (4)
- they lower patient resistance to infection
- masks symptoms of disease
- prolongs course of HSV
- enhances ocular susceptibility to fungal infection
88
Principles of corticosteroid therapy
- the type/location of inflammation determine the route of administration
- dosage must be appropriate, reviewed, and modified during therapy according to the response
- LONG TERM, HIGH DOSE therapy should be tapered rather than discontinued abruptly to avoid rebound inflammation
89
What ophthalmic preparations of steroids are best when corneal epithelium is intact?
acetate and alcohol
90
What ophthalmic preparation of a steroid is better to use if the corneal epithelium is damaged?
Phosphate
91
In general, which preparation(s) is/are better for topical corticosteroids?
acetates and alcohols
92
What are the topical ophthalmic corticosteroid agents?
- prednisolone
- dexamethasone
- difluprednate
- fluorometholone
- loteprednol etabonate
- rimexolone
93
What is the gold standard topical steroid?
- Prednisolone acetate 1% (PredForte)
| - have to shake because it's a suspension - tell the patient to shake 100X
94
Properties of dexamethasone (3)
- not well-metabolized once in AC
- very good anti-inflammatory properties - very strong steroid
- HIGHER INCIDENCE OF ELEVATED IOP compared to prednisolone acetate
95
What combo drops include dexamethasone?
- Maxitrol (polymyxin B, neomycin) - ointment AND solution AND generic; Dr. Marrelli doesn't like because patient can have high IOP and contact dermatitis with neomycin
- Tobradex (tobramycin) - ointment (brand) AND solution (brand/generic) - is the #1 Ab/steroid combo drop, these become problematic when considering tapering
96
Properties of difluprednate (5)
- newest ophthalmic steroid
- VERY POTENT ketone steroid (more likely to increase IOP than ester steroid), formulated in emulsion
- HIGHER INCIDENCE OF IOP ELEVATION than prednisolone acetate
- Durezol 0.5% emulsion
- can be dosed less often than prednisolone acetate 1%
97
Properties of fluorometholone (FML) (3)
- structurally unrelated to prednisolone or dexamethasone
- available as alcohol 0.1% suspension or ointment, 0.25% suspension (FML Forte), acetate 0.1% suspension (Flarex)
- generally considered a "weaker" steroid; reasonable for external inflammation (lids, conj, episcleral, etc.)
98
Properties of loteprednol etabonate (4)
- ester-based
- site-specific steroid aka "soft" steroid = rapid metabolism
- originally considered to be equivalent in anti-inflammatory properties to prednisolone acetate, now thought to be somewhat less effective but still good efficacy
- SIGNIFICANTLY REDUCED POTENTIAL to cause elevated IOP than prednisolone acetate 1%
99
Brand names and formulations for Loteprednol Etabonate (6)
- Lotemax 0.5% ointment, and generic suspension
- Lotemax 0.5% gel drops (brand only)
- Lotemax SM 0.38% gel drops (brand only)
- Inveltys 1% suspension (brand only)
- Alrex 0.2% suspension for allergies
- Zylet 0.5% combination with tobramycin
100
What is Lotemax FDA approved for and dosing?
TID dosing for post-surgical inflammation
101
What is Inveltys used for and its dosing?
BID dosing for post-op inflammation
102
Is Rimexolone (Vexol 1%) still available?
No
103
List the topical steroids from highest chance of increasing IOP to lowest chance of increasing IOP
Dexamethasone, difluprednate, prednisolone, loteprednol, fluorometholone
104
What is the mechanism that causes decreased IOP in uveitis?
ciliary body shuts down, which leads to less aqueous being produced
105
What are the mechanisms that cause an increased IOP in uveitis?
- trabeculitis, leading to resistance to outflow
- cellular debris clogging trabecular meshwork
- posterior or anterior synechiae
106
What are some of the golden rules to keep in mind when prescribing a steroid? (3)
- NEVER prescribe a steroid without measuring IOP first
- ALWAYS measure IOP on follow-up for patients on steroid
- NEVER allow refills of steroids, unless IOP is routinely checked
107
What should you do if patient has elevated IOP that is intolerable?
Add IOP-lowering therapy
108
How do steroids affect infections? (4)
- masks symptoms of disease
- prolongs the course of HSV
- enhances ocular susceptibility to fungal infection
- may reduce scarring in the cornea
109
When should a steroid be tapered?
When it's been used at high doses long-term
110
Which steroid bases have better penetration if the corneal epithelium is intact?
Alcohols and acetates
111
Which steroid bases have better penetration if the corneal epithelium is compromised?
phosphates
112
Which bases of steroids have better efficacy?
Acetates and alcohols
113
What formulations are phosphate-based steroids?
Solutions
114
What formulations are acetate-based steroids?
Suspensions
115
What formulations are alcohol-based steroids?
Either suspensions or solutions
116
Which steroid probably has the most flexibility according to Dr. Marrelli?
Prednisolone (she loves this drug)
117
What are some characteristics of prednisolone? (2)
- synthetic analog of hydrocortisone
| - available in acetate (suspension) and phosphate (solution) formulations
118
What are the formulations of prednisolone that we can prescribe? (3)
- prednisolone acetate 1% suspension (PredForte): brand is better than generic because it has smaller, more uniform, particle size
- prednisolone acetate 0.125% suspension (PredMild): no generic available
- prednisolone phosphate 1% solution: generic only, but not used very often
119
What are some characteristics of dexamethasone? (3)
- not well-metabolized once it enters the anterior chamber
- very good anti-inflammatory properties - very strong steroid
- HIGHER INCIDENCE OF ELEVATED IOP compared to prednisolone acetate
120
What are some formulations that we can prescribe of dexamethasone? (3)
- dexamethasone 0.1% alcohol suspension (Maxidex): available as a generic
- Maxitrol (with polymyxin B and neomycin): ointment and solution, brand and generic (Dr. Marrelli doesn't like high chance of IOP increase with chance of contact dermatitis with Neo)
- Tobradex (with tobramycin): ointment (brand) and solution (brand/generic)
121
What are some characteristics of difluprednate? (4)
- newest ophthalmic steroid
- VERY potent ketone steroid, formulated in emulsion, so no shaking required
- HIGHER INCIDENCE OF IOP ELEVATION than prednisolone acetate
- can be dosed less often than prednisolone acetate 1% by about half
122
What is the formulation we can prescribe of difluprednate?
Durezol 0.5% emulsion
123
What are some characteristics of fluorometholone? (2)
- structurally unrelated to prednisolone or dexamethasone
| - generally considered a "weaker' steroid; reasonable for external inflammation (lids, conj, episcleral, etc.)
124
What formulations of fluorometholone can we prescribe? (3)
- FML 0.1% alcohol (FML and generic, suspension or oinment)
- FML 0.25% suspension (FML Forte): clinically not more anti-inflammatory effect, just more potential to raise IOP
- FML 0.1% acetate suspension (Flarex): has better corneal penetration to reach AC
125
What are some characteristics of loteprednol etabonate? (3)
- ester-based steroid
- "site-specific" steroid aka "soft" steroid = rapid metabolism
- originally considered to be equivalent in anti-inflammatory properties to prednisolone acetate, now thought to be somewhat less effective (but still good)
126
What formulations of Loteprednol etabonate can we prescribe? (6)
- Lotemax 0.5% ointment, and generic suspension
- Lotemax 0.5% gel drops (brand only)
- Lotemax SM 0.38% gel drops (brand only): TID dosing for post-op inflammation
- Inveltys 1% suspension (brand only): BID dosing for post-op inflammation; nanoparticles with mucus-penetrating attributes for enhanced penetration through mucus barriers
- Alrex 0.2% suspension: allergies
- Zylet (0.5% loteprednol with tobramycin)
127
Reminder to go through the slides to find
Her list of steroid drugs that will probably be used on a prescription writing question
128
What side effect is most common with topical steroids?
increased IOP
129
What ocular side effect is more common with systemic steroids?
cataracts
130
What are some examples of local steroid injections? (3)
- periocular injections for chronic uveitis, cystoid macular edema
- intralesional injection of chalazion
- intravitreal injections and implants for macular edema, posterior noninfectious uveitis
131
What are some side effects of systemic steroid therapy? (8)
- adrenal insufficiency (Addison's)
- cushings syndrome
- peptic ulcer disease
- osteoporosis
- systemic hypertension
- diabetes/hyperglycemia
- infection (opportunistic pathogens)
- psychiatric changes: can be pretty severe, insomnia
132
Symptoms of Cushing's disease (5)
- weight gain (especially in the trunk)
- HTN
- "moon face"
- hyperglycemia
- a fat pad on the back
133
Symptoms of Addison's disease (5)
- weight loss
- low blood pressure
- hypoglycemia
- fatigue
- skin hyperpigmentation
134
What are the benefits to alternate day therapy for steroid use?
avoids adrenal suppression and steroid dependence (Addisons)
135
Oral steroids are safe for SHORT term use IF (4)
- NO GI disease (peptic ulcer disease: NO!)
- no psychiatric illness
- no hypertension
- no diabetes
136
What are some characteristics of oral methylprednisolone? (4)
- high potency
- convenient: automatically tapers over 6 days of therapy
- inexpensive
- relatively safe
137
What are some precautions when taking oral methylprednisolone?
- take with food or milk to avoid GI upset
| - avoid in diabetes, gastric ulcer patients, hypertension, psychiatric patients
138
When and why would we use systemic steroids?
- severe inflammation of posterior segment, orbit, and optic nerve: scleritis, uveitis, inflammatory orbital pseudotumor, GCA (can cause CRAO), optic neuritis, thyroid eye disease
- severe dermatologic manifestations: periocular insect bite, acute allergic blepharodermatoconjunctivitis
- Bell's palsy: CN VII pass through canal in temporal bone, where inflammation produces a compressed neuropathy
139
Differentials of Bell's palsy (4)
- infectious (lyme, HZV)
- autoimmune (Guillain-Barre, sarcoidosis)
- tumor
- stroke
140
How to diagnose Bell's palsy
- often preceded by postauricular pain, dysgeusia, and hyperacusis
- acute onset that progresses to complete facial hemispheres within 72 hours (slower progression than stroke)
- involves whole half of face, stroke involves lower quadrant often
141
How to treat Bell's palsy
- oral prednisone 50-60mg/day for 10 days, followed by taper for 5 days (taper by 10mg/day)
- oral antivirals, not sure if really effective
- PROTECT ocular surface with lubricants, patch, tape, etc. while waiting for recovery
142
What do mast cells release when they degranulate? (8)
- histamine
- tryptase
- prostaglandin D2
- leukotrienes
- eosinophilic chemotactic factors
- platelet-activating factors
- proteases
- cytokines
143
Type I (humoral) hypersensitivity
- allergen activates B-lymphocyte; IgE binds to mast cells and basophils (sensitization)
- cell membrane now more permeable to calcium ions; calcium influx triggers phospholipase A2 in mast cells
- mast cell degranulates
144
What are the components of allergic response? (6)
- itching - hallmark
- tearing
- mucus production
- conjunctival vasodilation
- increased vascular permeability
- papillary hypertrophy
145
Type 1 Reaction (SAC, PAC)
- occurs minutes to hours after exposure with immediate phase (5-30 min) and late phase (4-6 hours, lasts 2 days)
- histamine release: benign - rhinitis/itching/sneezing/tearing or life-threatening - anaphylaxis
146
Type 4 (delayed, cell-mediated) reaction
- delayed onset of 12-72 hours after exposure mediated by activated T-cells
- cytokines, IL, and interferon activate macrophages - cytotoxic, phagocytic, and lytic
147
What is the primary chemical mediator in SAC/PAC?
histamine
148
What is the most common form of ocular allergy?
seasonal allergic conjunctivitis
149
SAC is often associated with
rhinitis and itchy throat
150
Is there permanent tissue damage with histamine release in SAC?
No
151
Signs of SAC
- lid swelling (ptosis)
- conjunctival hyperemia
- conjunctival chemosis
- papillary reaction
- diagnosis is usually clinical
152
VKC
- a combo of Type 1 and Type 4 hypersensitivities
- in addition to histamine, mediated by eosinophils (permanent tissue changes)
- rare in patients <3 or >25 yo
- males : females, 2:1
- last 4-10 years, then resolves
- more common in Mediterranean, central Africa, South America areas
- associated with atopy history in 15-60%
153
What are the 3 types of VKC?
- limbal
- tarsal (similar to GPC presentation)
- mixed
154
Is VKC usually bilateral and is it seasonal
- usually bilateral
| - most cases are seasonal or with seasonal exacerbations
155
Symptoms of VKC (7)
- itching
- tearing
- mucus production - lots of strands
- photophobia
- burning
- blepharospasm
- blurred vision (corneal molding)
156
signs of VKC (7)
- papillary reaction (inc GPC)
- conjunctival hyperemia/edema
- limbal gelatinous nodules
- Trantas dots at the limbus
- mucus discharge
- conjunctival fibrosis
- cornea: SPK, pannus, filaments, shield ulcer, keratoconus
157
AKC (5)
- combo response of Types 1 and 4 hypersensitivities
- most severe form of ocular allergy
- develops in up to 25% patients with allergic dermatitis
- often have history of food allergies, hayfever, hives (atopy)
- begins late teens/early 20s
158
AKC symptoms
- itching
- tearing
- watery discharge
- burning
- photophobia
- blurred vision
159
AKC signs (8)
- tylosis
- eyelid edema - permanent
- derm signs (scaly, wrinkled skin)
- Dennie-Morgan folds
- upper lid ptosis
- fissures @ lateral canthus
- Hertoghe's sign
- marginal blepharitis
160
Dennie- Morgan lines
the premature wrinkles under the eyes that patients with atopy get from their allergies
161
Hertoghe's sign
outer 1/3 of eyebrows are thin/gone
162
Corneal signs of AKC
- SPK, PEE
- microcystic edema
- corneal ulcer
- pannus/neo extending to central cornea
- keratoconus in 15-20% of AKC patients
163
Lens signs of AKC
- anterior subcapsular cataract
| - posterior subcapsular cataract
164
etiology of GPC
- EW of contact lenses beyond FDA approval
- exposed sutures
- prosthesis
- glaucoma surgery bleb
- scleral buckle
165
GPC symptoms
- itching
- FB sensation
- lots and lots of mucus production
- CL intolerance
166
non-pharmacological recommendations for allergies
- **keep hands away from eyes, so not to disturb/burst open mast cells to release more histamine**
- keep windows closed in peak season
- shampoo hair before bed
- undress in room other than bedroom
- use bed/mattress covers/frequent cleaning of bed and carpets for mites and dander
- run AC if mold is a problem
- high performance AC filters?
- artificial tears to wash away antigen and histamine/mediators
- saline rinse
- cold compresses
- avoid allergen
167
Order of stepped approach for topical therapy for allergies
- decongestants
- antihistamines
- mast cell stabilizers
- NSAIDs
- corticosteroids
- immune therapy
168
Order of stepped approach for oral therapy for allergies
- antihistamines (may cause dry eyes)
| - corticosteroids
169
Characteristics of decongestants "vasoconstrictors" (8)
- adrenergic agonists
- available with or without an antihistamine
- available OTC, inexpensive
- typically only slightly effective
- palliative only (doesn't improve the allergic response)
- tachyphylaxis - loses effect very quickly, so having to use more frequently
- rebound hyperemia/inflammation
- dosed BID - QID
170
Available topical decongestants (4)
- phenylephrine
- naphazoline
- oxymetazoline
- tetrahydrazoline
171
Side effects of topical decongestants (6)
- stinging
- pupillary dilation (primarily phenyl): not good for pts that are predisposed to angle closure
- epithelial erosion
- rebound congestion
- follicular conjunctivitis
- can affect cardiovascular system (sympathetic agonists)
172
Contraindications of decongestants
- narrow angles
| - uncontrolled cardiovascular disease
173
What is Upneeq?
- oxymetazoline that has an affinity for Mueller's muscle
| - used to treat acquired ptosis
174
Use of topical antihistamines (4)
- decrease itching, decrease capillary dilation and permeability, decrease mucus production
- may or may not decrease other symptoms (burning, pain)
- can be very effective in acute reaction (unlike mast cell stabilizer)
- not fast-acting enough to be useful in anaphylaxis
175
First generation topical antihistamines
- pheniramine maleate (Naphcon-A, Visine-A, Opcon-A)
- antazoline phosphate (Vasocon-A)
- both available only in combo with naphazoline; are OTC
- dosed QID
176
Second generation topical antihistamine and its characteristics
- emedastine (Emadine 0.05% sol): significant decrease in itching and redness in 10 minutes, duration of 4-6 hours, dosed QID
- selective H1-blockers, may also inhibit release of histamine and other mediators from mast cells
- cost $130-150
177
mast cell-stabilizing antihistamines (dual action) (6)
- olopatadine (Patanol 0.1%, Pataday 0.2%, Pazeo 0.7%)
- ketotifen (Zaditor 0.025%, Alaway, Claritin, Zyrtec)
- azelastine (Optivar 0.05% sol, generic)
- epinastine HCL (Elestat, and generic)
- bepotastine (Bepreve)
- alcaftadine (Lastacaft)
178
Dosing of Patanol 0.1%
- bid dosing, now called "Pataday Twice Daily Relief" (OTC)
179
Dosing of Pataday 0.2%
- once daily dosing
- for severe symptoms, may need 2nd dose
- now called "Pataday Once Daily Relief" (OTC)
180
Dosing of Pazeo 0.7%
- once daily dosing
- RX ONLY
- 4 mL = $200-300
181
Characteristics of Ketotifen (Zaditor 0.025%, Alaway, Claritin, Zyrtec) (6)
- definite mast cell stabilization
- may decrease chemotaxis and action of eosinophils
- rapid onset
- BID dosing
- OTC
- cost ~ $10-15
182
characteristics of azelastine (4)
- very rapid relief
- generic ~ $15
- terrible taste in mouth
- dosed bid
183
Characteristics of epinastine hcl (Eleastat, and generic) (3)
- dosed bid
- $250 brand, $30 generic
- less drying
184
Characteristics of bepotastine (Bepreve) (2)
- dosed bid
| - $250
185
Characteristics of alcaftadine (Lastacaft)
- dosed ONCE daily
| - $250
186
Characteristics of Cetirizine (Zerviate) (6)
- new topical antihistamine
- same medication as in Zyrtec oral antihistamine
- H1 antagonist
- used bid (approx 8 hrs apart)
- PRESCRIPTION ONLY
- 30 single-use vials $200
187
side effects of topical antihistamines
burning and stinging
188
contraindications of topical antihistamines
- possible to produce some mydriasis, so contraindicated in narrow angle patients (however very low risk)
189
characteristics of mast cell stabilizers (7)
- stabilize the mast cell from degranulation
- may have other mechanisms
- do not have an effect on histamine already released**
- lag time of 1-3 weeks (not so with newer ones)
- frequent dosing (qid+, except for newer ones)
- typically well-tolerated
- variable efficacy
190
mast cell stabilizer drugs
- cromolyn sodium (Crolom, Opticrom)
- lodoxamid (Alomide)
- nedocromil (Alocril)**
191
dosing/cost of cromolyn sodium (Crolom, Opticrom)
- qid
| - only generics now $10
192
lodoxamide (Alomide) cost, potency and dosing
- $175
- 2500X more potent!
- qid
193
nedocromil (Alocril)** cost, dosing, characteristics
- $225
- bid
- multicellular action
- quick decrease in symptoms
- yellow color
194
use/indications for NSAIDs
- block prostaglandin synthesis
- may have slight anesthetic effect
- may decrease symptoms associated with inflammation
- may rise "itch threshold"
195
uses of corticosteroids in regards to allergies
- typically reserved for severe cases (VKC, AKC, GPC)
- may be of benefit in conjunction with other agents
- loteprednol etabonate 0.2% (Alrex) is the only topical corticosteroid with FDA approval for ocular allergy; others may be used off-label
- NOT ok for extended dosing
196
Cyclosporine characteristics (4)
- Cequa, Restasis
- T-cell modulator that may have some value in allergies
- primarily in AKC, VKC
- NO FDA indication for allergic eye disease
197
things to consider with oral antihistamines (3)
- topical therapy is safer and more effective in most cases of ocular allergy
- may be appropriate when other signs and symptoms are present (lid swelling, itchy throat, runny nose)
- may actually exacerbate ocular symptoms (especially the more sedating ones)
198
first generation antihistamines (2)
- CNS depression/stimulation
| - anticholinergic effects
199
second generation antihistamines (2)
- less dry mouth/blurred vision
| - longer elimination time (less frequent dosing)
200
clinical uses of systemic antihistamines
- nasal and conjunctival itching, sneezing, coughing
- rhinitis
- eyelid edema
- urticaria
201
benefit of using topical antihistamine for ocular allergies
more direct and rapid effect on ocular surface
202
side effects of oral antihistamines (9)
- sedation
- dizziness
- tinnitus
- blurred vision
- anxiety
- insomnia
- tremor
- dry mouth
- GI upset
203
First generation oral antihistamines in order from least to most sedating
- chlorpheniramine
- clemastine
- diphenhydramine, promethazine
204
fexofenadine (Allegra) OTC dosing for children aged 12 and over
180 mg qd
205
fexofenadine (Allegra) OTC dosing for children aged 2-11
- 30 mg bid
- 30 mg rapid dissolve tab and regular tabs for aged 6-11;
- 30 mg/5mL oral suspension for 2-11 years
206
fexofenadine (Allegra) dosing for 6 months - under 2 years
- 15 mg bid
| - unsure if this is OTC
207
Allegra-D
fexofenadine with pseudoephedrine
208
Cetirizine (Zyrtec) dosing for adults and children 6 years and older
- 10 mg/day
209
Cetirizine (Zyrtec) dosing for children aged 2-5
- 2.5 mg/day
| - MAXIMUM 5 mg/day (single or divided)
210
Cetirizine (Zyrtec) dosing for children 6 months - under 2 years
- 2.5 mg/day
| - MAXIMUM 5 mg/day DIVIDED
211
Available forms of Cetirizine (Zyrtec)
- 5 mg, 10 mg tablets
- 5 mg, 10 mg chewable tablets
- 1 mg/mL oral syrup
212
What is the minimum age Zyrtec-D should be given?
12 years
213
What is the dosing for Desloratadine (Clarinex) for adults and children 12 years and older?
5 mg QD
214
Desloratadine (Clarinex) dosing for children 6-11 years
- 2.5 mg per day
215
Desloratadine (Clarinex) dosing for children 12 months to 5 years
1.25 mg per day
216
Desloratadine (Clarinex) dosing 6-11 months
1 mg per day
217
Available forms of Desloratadine (Clarinex)
- 5 mg tabs
- 5 mg, 2.5 mg redi-tabs (oral dissolving)
- syrup 2.5mg/5mL
- Clarinex-D: with pseudoephedrine
218
Loratadine (Claritin) minimum age to take
2 years
219
Available forms of Loratadine (Claritin)
- 10 mg tabs
- 10 mg liquigels
- syrup 5mg/5mL
- adult and children red-tabs - 10 mg once daily or 5 mg twice daily
- children chewable tabs 5 mg once daily
- claritin-D: with pseudoephedrine
220
Side effects of oral antihistamines
- sedation (worse with alcohol)
- palpitations
- drying of secretions
- GI disturbance
- dry eye
- mydriasis
- decreased accommodation
221
Contraindications of oral antihistamines
- 1st and 3rd trimester pregnancy
- nursing mother
- strong anticholinergic H-1 blockers: peptic ulcer disease, prostate hypertrophy, bladder obstruction, narrow angles
222
Different types of pain
- acute
- chronic
- neuropathic: from diseases of the nerves or injury to nerves
- syndrome pain
223
Most ocular pain is ____
Acute
224
physiological effects of pain
- tachycardia
- systemic hypertension
- tachypnea
- exacerbation of pre-existing cardiovascular disease
225
psychological effects of pain
- poor sleep patterns
- anxiety/depression
- uncooperativeness
226
What do neurons release upon pain?
Substance P
227
What does substance P stimulate?
mast cells and blood vessels
228
What is the ascending pathway of pain?
- nociceptors on afferent nerve endings send AP to dorsal horn of SC
- alpha-delta fibers: sharp localized pain (somatic pain); activated by chemical, thermal or mechanical stimuli (most eye pain)
- C-fibers: dull, diffuse, aching pain (visceral pain); stimulated by bradykinin and prostaglandins
- alpha-delta and C-fibers release substances in dorsal horn of SC that activate secondary neurons (from ascending spinothalamic pathway) --> thalamus --> third order neuron to somatosensory cortex
229
Descending pathway of pain
- starts in midbrain/medulla --> dorsal horn
| - release NE, 5-HT, and endogenous opioid NTs; inhibit ascending pathway activity
230
Reminder to look at slides
For the pain pathway picture
231
Three categories of analgesics
- opioid
- non-opioid
- analgesics used to treat specific pain syndromes
232
opioid terminology (3)
- narcotic: term that refers to opioids; a drug that produces a stuporous, sleeplike state (may or may not relieve pain)
- opiates: refers to drugs specifically isolated from poppy (morphine and codein)
- opioids: compounds of any type that interact with opioid receptors (3 types of receptors)
233
non-opioid analgesic characteristics (3)
- work on nociceptor pain (peripheral part of pain response)
- includes NSAIDs which have analgesic, antipyretic, and anti-inflammatory properties
- also includes acetaminophen (no anti-inflammatory properties)
234
analgesics used to treat specific pain syndromes
treat neuropathic pain, migraine, gout, etc.
235
peripheral agents: NSAIDs properties (3)
- act on peripheral pain receptors and prevent sensitization/discharge of nociceptors
- do not produce tolerance/dependence
- good for mild to moderate pain
236
what is the mechanism of acetaminophen?
- not really known but similar to NSAIDs but may only work in the CNS
237
characteristics of central agents/opioids
interact with specific receptors in the CNS - interrupt pain message and its emotional response
238
peripherally acting agents characteristics (2)
- prevent sensitization and discharge of nociceptors
- NSAIDs (including aspirin) block the formation of inflammatory and pain mediation (prostaglandins) at the cyclooxygenase pathway
NSAID shave analgesic, anti-inflammatory and anti-pyretic properties
239
reminder to look at the slides for
the inflammatory cascade and where NSAIDs work
240
What do both COX enzymes produce?
prostaglandins that contribute to pain, fever and inflammation
241
What does COX-1 enzyme produce and what type of enzyme is it?
- prostaglandins that activate platelets and that protect the stomach and intestinal lining
- constitutive enzyme
242
What does COX-2 enzyme produce and what type of enzyme is it?
- responsible for production of prostanoid mediators of inflammation (prostaglandins, prostacyclins, thromboxane)
- inducible enzyme
243
salicylate characteristics (3)
- non-specific cyclooxygenase blocker
- clot prevention vs analgesic vs anti-inflammatory doses
- acetylated vs non-acetylated
244
Why was non-acetylated salicylic acid developed?
to reduce GI upset and GI bleeding
245
ASA (aspirin) characteristics (5)
- irreversibly block platelets (75 mg qd)
- best for use as an anti-coagulant
- none are safe in potential "bleeders"
- adult dose is 325-650 mg every 4 hours (not more than 4 g/d) for pain/inflammation
- take with food, full glass of water
246
non-selective NSAIDs other than ASA characteristics (5)
- less bleeding potential
- less GI upset
- greater efficacy compared to ASA
- all have same efficacy in comparable doses
- all have similar side effects
247
comparable doses of non-selective NSAIDs
- diclofenac 50mg qid
- ibuprofen 800mg qid
- naproxen sodium 220mg bid-tid
- ketoprofen 300mg/day
248
comparable doses of cox-2 inhibitors
- celecoxib/celebrex 200mg bid
249
NSAID side effects/adverse effects
- inhibit platelets (only ASA is irreversible)
- GI upset
- GI bleeding/ulcer/perforation
- increased risk of serious cardiovascular thrombotic events (heart attack/stroke) - FDA increased warnings in 2015
250
Use NSAIDs with caution in patients with which pre-existing conditions? (7)
- asthmatics/nasal polyps: aspirin-induced respiratory disease or aspirin-induced asthma
- hypersensitivity (allergic to whole class)
- diabetics: risk of increased protein binding in Type 2 and risk of renal insufficiency
- children with fever, chicken pox, flu-like symptoms: NO ASA
- avoid in pregnant/nursing mother
- avoid in patients with GI problems
- avoid in bleeding disorders, vitamin K deficiency, anticoagulant therapy
251
max dosing for ibuprofen
800mg qid (3200mg/day)
252
ophthalmic NSAIDs
- ketorolac tromethamine
- nepafenac
- diclofenac
- bromfenac
- flurbiprofen
253
ketorolac tromethamine uses
- 0.5% (Acular, generic): itching associated with SAC: 1 gtt qid,
post-op pain and inflammation: begin 24 hours pre-op, continue x 2 weeks
- 0.4% (Acular LS, generic): up to 4x daily for post-refractive surgery pain
254
nepafenac uses
- post-op inflammation and pain but both forms are expensive
- 0.1% (Nevanac): tid following cataract surgery
- 0.3% (Ilevro): once daily dosing
255
diclofenac uses
- pain and inflammation after surgery
- 0.1% (Voltaren, generic)
- cataract and refractive surgery - qid dosing
- report of rare corneal decompensation - mostly with generic formulation issue
256
bromfenac uses
- pain and inflammation after cataract surgery
- once daily dosing
- 0.07% (Prolensa)
- 0.09% (generic)
257
flurbiprofen uses
- older, potentialy less effective
- 0.03% (generic)
- used by surgery DURING surgery (provides miosis)
258
notes about topical NSAIDs (3)
- any use other than post-cataract or refractive surgery pain and inflammation is OFF-LABEL (other than ketorolac for allergies)
- can help with ocular pain from other causes
- some are used for post-cataract surgery CME
259
ways to manage corneal pain (5)
- lubricants
- bandage CL
- pressure patch
- cycloplegia
- topical NSAIDs (OFF-LABEL)
260
what conditions is cycloplegia useful for?
- corneal abrasion
- corneal FB
- infectious keratitis
- anterior uveitis
261
what other analgesic besides NSAIDs?
- acetaminophen = APAP (Tylenol)
- unknown central mechanism
- antipyretic - works on hypothalamus - good for aches/fever
- NO ANTI-INFLAMMATORY EFFECT - not good for swelling
- NO INHIBITION OF PLATELETS
262
acetaminophen is the DOC for?
- children
- viral-induced fever
- pregnancy
- nursing mothers
- patients with GI disorders
- patients with bleeding/clotting disorders
- overall safer drug and can be given after surgery
263
acetaminophen max dosing
- now recommend 3200mg/d but can use 4g/d for short periods of time
264
acetaminophen dosing
- regular strength: 325 mg tab or cap: 1-2 pills every 4-6 hours, not to exceed 10 tabs in 24 hours
- extra strength: 500 mg tab or cap: 1-2 pills every 4-6 hours not to exceed 6 pills in 24 hours
265
pediatric availability of APAP
- oral suspension 160mg/5mL
- chewable tablet 160mg tab (choking hazard until 3-4 years old)
- dissolvable powder 160mg/powder pack
266
acetaminophen and the liver
- APAP is associated with liver failure in alcoholics/people who consume >3 drinks/day bc of how it's metabolized
- liver failure = decreased drug metabolism = overdose
- major pathway: majority of drug is metabolized to produce non-toxic metabolite
- minor pathway: small amount of drug produces highly reactive intermediate that conjugates with glutathione and is inactivated
- at TOXIC APAP levels, the minor pathway can't keep up (liver's glutathione is limited), causing an increase in the reactive intermediate which is hepatotoxic
267
centrally acting agents characteristics (4)
- react with opioid receptors in the CNS
- interrupt the ascending pain message AND the emotional response
- opioids (morphine, oxycodone, codeine) MOA poorly understood
- endorphins - naturally manufactured by the brain, they may block peripheral transmitters or hyperpolarize neurons (opioids mimic endorphins)
268
MU opioid receptors
- classic morphine receptor and most common endogenous opioid receptor
- located in brain and spinal cord
- stimulated by endogenous endorphins
- drug ligands: morphine, methadone, fentanyl
- effects decline as tolerance develops
269
binding of mu receptors produces
- analgesia
- sedation
- decreased BP
- itching (not allergy)
- nausea/GI upset/constipation
- euphoria (potential for abuse)
- decreased respiration
270
kappa opioid receptors
- stimulation relieves pain
- stimulation produces nausea, sweating
- endogenous transmitters are dynorphins
- located in the periphery by pain neurons
- NOT associated with euphoria response
271
delta opioid receptors
- stimulated by endogenous enkephalins
- produces "ischemic preconditioning" - effect they have on tissue after stroke to reduce its effect
- stimulation induces protective increase in blood flow to tissues surrounding an ischemic area
- may have cardioprotective effect
272
opiate analgesics
- block central pain receptors, reduce perception of pain
- inhibits descending pain pathways
- allergic to one opiate, allergic to all**
- schedule II (high abuse potential) to V (low)
273
narcotics
- morphine
- codeine
- heroin
- fentanyl
- methadone
- hydrocodone
- thebaine
- oxycodone
- meperidine
- tramadol
274
side effects of opiates
- respiration: sleep apnea/COPD
- urinary tract: enlarged prostate
- GI tract: slows motility/constipation warning
- interaction with other anticholinergics (dry/drowsy)
275
withdrawal reactions
- pain/irritability
- hyperventilation
- dysphoria and depression
- restlessness and insomnia
- fearfulness and hostility
- increased blood pressure
- nausea/vomiting/diarrhea
- pupillary dilation
- hyperthermia
- lacrimation/runny nose
- chills/goosebumps
276
Tylenol 1, 2, 3, 4 combination
- codeine with APAP
277
Vicodin combination
- hydrocodone and APAP
278
Percodan combination
oxycodone and ASA
279
Percocet combination
oxycodone and APAP
280
ultracet combination
tramadol and APAP
281
how much codeine is in tylenol 4?
60 mg
282
how much codeine is in tylenol 3?
30 mg
283
how much codeine is in tylenol 2?
15 mg
284
how much codeine is in tylenol 1?
7.5 mg
285
how many days' worth of scheduled drugs can we prescribe as ODs?
three (which is plenty for eye pain)
286
what combination of tylenol and ibuprofen can give the equivalent pain relief as opioids without the unwanted side effects?
500-1000mg Tylenol + 400-600mg ibuprofen taken simultaneously
287
herpes zoster post-herpetic neuralgia
- pain that lasts 3 months or longer after shingles rash has cleared
- burning, stabbing, deep, aching pain
- sensitive to touch
- itching and numbness
- a leading cause of suicide in older patients
288
who's at risk of getting PHN?
- older than 50
- severe rash and pain (worse case)
- other chronic conditions (diabetes)
- face/torso location of rash
- delayed antiviral therapy
289
how to manage post-herpetic neuralgia?
- prevent: recognize HZ and prescribe oral antivirals ASAP
- treat:
- oral antivirals during acute phase
- Zostrix cream to area 3-4 times per day (capsaisin)
- low dose tricyclic antidepressants (amitriptyline 25mg/d)
- gabapentin (Neurontin) - huge dose range
- 5HT agonists ("triptan" drugs)
- involve the PCP for treatments
290
local anesthetics definition
drugs which produce reversible (transient) loss of sensory perception without producing loss of consciousness
291
characteristics of local anesthetics
- used in diagnostic and therapeutic procedures to numb a small part of the body
- prevent the generation and conduction of a nerve impulse
292
how do local anesthetics work?
- unionized form penetrates the cell membrane
- inside of neuron is slightly more acidic so anesthetic becomes ionized and has a high affinity for sodium channel - prevents influx of sodium into cell
293
chemical structure of local anesthetics (3 main parts)
- lipophilic group: aromatic structure (usually benzene) - as lipophilicity increases, potency, duration of action and toxicity increases
- intermediate linkage group: either ester ( -CO) or amide ( -HNC) - determines properties such as metabolism: ester is unstabilized compared to amide
- hydrophilic group: usually a tertiary amine/proton acceptor
294
esters vs amides
esters - unstable, quickly hydrolyzed by pseudocholinesterases
amides - stable, metabolized by the liver and last longer
295
between esters and amides, which are more likely to produce allergic reactions?
esters, but allergies to anesthetics are not very common
296
examples of ester local anesthetics
- cocaine
- tetracaine
- proparacaine
- benoxinate
297
examples of amide local anesthetics
- bupivacaine**
- lidocaine**
- ropivacaine
- etidocaine
- mepivacaine
298
general concepts of local anesthetics
- affect every nerve, not just pain: autonomic, pain, temperature, touch, proprioception, motor fibers (although need lots to paralyze)
- preferentially affect: smaller nerves, myelinated nerves, nerves that fire frequently
299
factors that affect POTENCY of local anesthetics
- hydrophobicity
- hydrogen ion balance
- vasoconstrictor/dilator properties
- fiber size, type, myelination
- frequency of nerve firing
- pH (acidic environment antagonizes the block)
300
duration of action of LA
- anesthetics have some inherent vasodilation activity which can impact potency/doa
- vasoconstrictors may be added to INJECTABLE local anesthetics to prolong time in tissue (typically epinephrine 1:100,000 concentration)
- vasoconstrictors decrease potential for systemic toxicity but may cause local tissue hypoxia
- protein binding can increase duration of action
301
examples of short-acting LAs
- procaine
| - chloroprocaine
302
examples of intermediate acting LAs
- lidocaine
- mepivicaine
- prilocaine
303
examples of long acting LAs
- tetracaine
- bupivacaine
- etidocaine
- ropivacaine
- lovebupivacaine
304
side effects of TOPICAL anesthetics
- severe SE are extremely uncommon
- minor toxic or allergic events involving eyelids, conjunctiva, cornea
- toxicity: desquamation of epithelial cells of cornea (more common in elderly, can decrease vision temporarily)
- systemic reactions are even more rare
- max 7 drops/eye tetracaine; 14 drops/eye proparacaine
305
prolonged topical anesthetic syndrome
- occurs after 6 days to 6 weeks of use
- severe corneal lesions with decreased epithelium
- after just a few days: loss of epithelium, delayed/retarded healing of epithelial defect
treat: d/c anesthesia, cycloplegia, antibiotic, bandage CL, systemic analgesic
306
reminder to
read articles on teams regarding prolonged topical anesthetic use
307
allergies to local anesthetics
- true allergy to amides is EXTREMELY rare; need to know what type of anesthetic and situation
- true allergy to esters is uncommon, except common dermatitis hypersensitivity to benzocaine
308
acute toxicity to local anesthetics
- typical order: CNS, cardiovascular, respiratory
309
CNS acute toxicity to local anesthetics
- stimulation followed by depression
- paresthesia, tinnitus, dizziness, lightheadedness
- anxiety --> disorientation --> loss of consciousness --> seizure --> respiratory arrest
310
cardiovascular acute toxicity to local anesthetics
- early: hypertension, tachycardia, arrhythmia
| - late: hypotension, bradycardia, absent pulse (all are negative inotropes)
311
psychomotor acute toxicity of local anesthetics
anxiety-related, NOT drug-related
312
characteristics of topical anesthetics in OD practice
- allow us to perform diagnostic and minor surgical procedures in office while keeping patient comfortable
- drugs applied to conjunctiva/cornea
- most topical anesthetics are similar in their onset/doa
- do not provide anesthesia to skin surface (cannot use in eyelid lesion removal)
- vary in ability to provide anesthesia to conjunctiva/limbus, but ALL do well on the cornea**
313
topical anesthetics that are derivatives of PABA
- tetracaine 0.5%
| - benoxinate 0.4%
314
forms of proparacaine
- 0.5% solution
- 0.5% with fluorescein sodium (Fluoracaine and Flucaine)
- a little more tolerable than tetracaine
315
forms of lidocaine
- 3.5% gel (Akten) - AMIDE
| - rarely used because it's inconvenient and rough on cornea
316
characteristics of proparacaine
- low incidence of hypersensitivity
- more comfortable than tetracaine, so generally considered DOC
- however, has less conjunctival anesthesia than tetracaine
317
characteristics of tetracaine
- similar to proparacaine but has more stinging and more impact on corneal epithelium
- some cross-reaction hypersensitivity with proparacaine
318
characteristics of Benoxinate 0.4% topical anesthetic
- stinging level between tetracaine and proparacaine
319
characteristics of lidocaine 3.5% gel (AMIDE)
- much better anesthesia for deeper conjunctiva
- occasional use in optometry
- no cross-sensitivity with other topicals (esters)
- efficacious on vascular tissue
- no local metabolism = long lasting
320
side effects of topical anesthetics
- conjunctival hyperemia
- tearing
- eyelid heaviness
- increased corneal epithelial permeability
- corneal epithelial desquamation
- blink reflex diminished
- delay contact lens use for 30-60 minutes post-use
321
uses of topical anesthetics in optometry
- tonometry
- gonioscopy
- culturing of ocular tissues
- forced ductions (lidocaine)
- pachymetry
- lacrimal dilation and irrigation
- pre-drug instillation
- superficial foreign body removal
- minor surgery of conjunctiva
- prior to injected anesthesia
322
optometric uses of injectable anesthetics
- eyelid lesion removal
- chalazion incision and drainage
- repair of eyelid laceration
323
different methods of injectable anesthetics
- local infiltrative - provide excellent anesthesia to anterior lamellae, but distort tissue, used with epi
- regional nerve block - excellent anesthesia without tissue distortion, no epi, must know anatomy extremely well*
324
injectable local anesthetics
- lidocaine 0.5 to 2% with or without epi: onset 4-6 minutes, lasts 40 min - 1 hour
- bupivacaine 0.5% usually without epi: onset 5-10 minutes, lasts 4-12 hours, often combined with lidocaine
325
pre-injection evaluation
- age (has to be cooperative if child)
- systemic health
- medications
- allergies (RARE to have amide anesthetic allergy)
- level of anxiety (may need to administer diazepam if patient has a driver)
326
procedure of injecting anesthetics
- informed consent prior to injection
- clean area to be injected with disinfectant
- mark skin if needed
- jaeger plate if desired
- 25-27 gauge needle in tuberculin syringe
- bevel up and skin pulled taut, very shallow angle to inject, withdraw plunger to ensure no IV penetration
- inject 0.2 to 0.6 cc while withdrawing syringe
- SLOW and steady injection to decrease pain
- WATCH for diffuse rather than linear infiltration
- 2-3 injection sites may be needed
- pressure/massage to disperse bolus, restore anatomy and decrease hematoma risk
- after 5 minutes: pinch to skin to see if anesthetized
