Opthalmic

Question 1

Intraocular pressure normal

Answer 1

16 +/-5 mmHg

Question 2

Intraocular pressure is determined by?

Answer 2

Mainly aqueous humour in anterior chamber, vitreous humor and blood within eye, scleral compliance and extraocular muscle tone

Question 3

How anesthesia increased IOP

Answer 3

Venous congestion, coughing/bucking, pressure on eye by face mask, extraocular muscle contraction by succ, HTN, hypoxemia, hypoventilation, ketamine, sympathetic stimulation (dilates eye)

Question 4

Oculocardiac reflex defined

Answer 4

“five and dime” Decrease in heart rate and blood pressure due to afferent limb of trigeminal nerve to cardio inhibitory vagal center efferent to vagus

Question 5

Oculocardiac reflex management

Answer 5

Notify the surgeon to stop, optimize oxygenation and ventilation, possibly atropine 20 mcg/kg or glycopyrrolate

Question 6

Echothiophate

Answer 6

Prolong succ and mivacurium

Question 7

Scopolamine

Answer 7

Central anticholinergic

Question 8

Cataract surgery and anesthesia

Answer 8

phacoemulsification with IOL (intraocular lens placement), sometimes retrobulbar block with short acting sedative/narcotic and then MAC

Question 9

Retrobulbar block gets which nerves?

Answer 9

Trigeminal, Trochlear, Abducens, Oculomotor

Question 10

Retrobulbar block complications

Answer 10

Oculocardiac reflex, hemorrhage, globe puncture, intradular/vascular injection

Question 11

Brainstem anesthesia

Answer 11

Get loss of consciousness, apnea and cardiac instability, possibly mydriasis and contralateral eye block

Question 12

Peribulbar block

Answer 12

Needle outside cone- decreases complications but get less motor block and need to use more volume of local

Question 13

Sub-Tenon’s block

Answer 13

Instilling local by blunt cannula into space between globes sclera and sub-Tenon’s capsule

Question 14

when is Facial nerve block used

Answer 14

If surgeon does not want blinking

Question 15

Trabeculectomy

Answer 15

creates a new drainage system for eye - usually with glaucoma surgery

Question 16

Glaucoma anesthesia

Answer 16

Sedation with block, if GA use smooth induction to minimize increase in IOP

Question 17

Squints surgery anesthesia

Answer 17

strabismus surgery - done under GA, high incidence of OCR and PONV, possibly increased risk of MH, avoid ketamine due to nystagmus

Question 18

Keratoplasty

Answer 18

corneal surgery from penetrating to full thickness- can be done under MAC or GA

Question 19

Blepharoplasty

Answer 19

Eyelid surgery to remove excessive tissue

Question 20

Ptosis repair

Answer 20

Corrects dropping

Question 21

Dacrocystorhinostomy

Answer 21

Repair of lacrimal sac communication to nasal passage (cocaine works well except with old bad hearts)