Ocular Anesthetics- For Exam 2 Flashcards
(broad) drugs causing reversible blockage of the conduction of a nerve fiber, by limiting sodium ion permeability by closing pores through which the ions migrate in the lipid layer of the nerve cell membrane
topical anesthetics
Anesthetic drug that is not synthetic - natural
cocaine
Deriviatives from PABA, metabolized by hydrolysis
Esters - cocaine, proparacaine (sx), chloroprocaine (sx), tetracaine, benoxinate, procaine
Derivative from aniline, metabolized by liver and excreted in urine, highly water soluble
Amines (usually injections)- lidocaine (sx), mepivacaine (sx), bupivacaine (sx)
anesthetic used for minor ANTERIOR SEGMENT procedures
Lidocaine
pH for anesthetics
8-9, contributes to stability and shelf life
Used by surgeons to cause vasoconstriction during surgery to enhance action of anesthetics
Epinephrine
affinity, concentration, quantity, mode, speed
factors affecting anesthetic potential
Mode used for facial nerve block, retrobulbar or peribulbar anesthesia, eyelid infiltration
Injectable
Mode used for Gonio, Tono, and pretty much everything else in clinic requiring prolonged contact
Topical
renal impairment is a warning for which anesthetic
Mepivacaine
Hepatic function is a warning in which group of anesthetics
amines
Anesthetic Drug contraindicated in children due to its strength
Bupivacaine
Ester of MABA, 0.5% solution, works fast, lasts 20 min. most commonly used in clinic- tono, SE transient irritation, stinging, delayed tissue healing, erosion of eye is dry - Take IOP after refraction, allergic reactions- exacerbate conjunctiva bullae in Steven’s Johnson Syndrome
Proparacaine HCL
Ester of PABA, 0.5% solution, no anesthetic effect on sclera and can cause more allergic rxn than proparacaine SE: severe keratitis and erosion
Tetracaine HCL
Ester of PABA, similiar to propa and tetra, .4%, 0.35%- RGP fitting, slight risk of pseudomonas infection, SE transient burning, less toxic than propa, less allergic rxn
Benoxinate
Amino amide, 3.5% viscous topical ocular anesthetic gel, 20-60 sec, lasts 5 to 30 min, 2 drops, used for all diagnostic and minor invasive therapeutic procedures where enhanced anesthesia is desired
Lidocaine
Indirect sympathomimetic natural alkaloid, vasoconstrictor, force duction test, epithelial debridement (viral removal), nasal spray for dacryocystorhinostomy, causes pupil dilation
Cocaine
Retrobulbar Injectable amino amide, most common for extensive retinal/cataract ocular surgeries, kidney function monitored, lasts 4 to 12 hours without epinephrine, high toxicity, better on all ocular tissues, Topical uses: superficial conj. lesions, FB removal, Suture removal, pterygium removal, SE erosions, keratitis, permanent corneal opacification
Bupivacaine
