Anesthesia for ophthalmic surgeries

Dr. Mohamed Ibrahem El saidM.D.

ContentIOP = intraocular pressureGeneral anesthesia Regional anesthesiaExtra ocular surgeries

IOP = normal 10 - 20

Factors affecting IOP• Increase IOP external pressre

( local anesthesia – face mask – retrbulber hemorrhage) – elevated CVP ( valsalve – MV – trendlenberg position ) increase arterial blood pressure ( valsalva – laryngioscope – straining ) PaCO2 & PaO2 (hypoxia – hypercarbia )

• Anesthetics and IOP inhalational – intavenous all decrease IOP except ketamine

• Sk.ms relaxant no effect except succinyle slight increase

• Anticholinergics = atropine slight increase

Oculo-medullary reflexesOculo-cardiac + respiratory + metric

reflexes• traction on extraocular muscles

med.rectus or pressure on eye ball• trigeminal and vagus • arrhythmia brady.VF .ectopy – resp.

arrest – nausea• Atropine + stop the surgon

General anesthesia in ophth.surg

Aim Slight decrease in IOP Patient refusal for local Eye liable for

complication High myope axial

length > 26 mm Open eye injury Children and young age

Mental disability Lengthy surgeries Coagulopathy

Anesthetic problems Type of patient young pediatric or

geriatric IOP control = optimize bl.pr prevent

straining – optimize CO2 ..... Patient covered and away from

anesthetist Occulo (cardiac - respiratory - metric)

reflexses Postoperative nausea Postoperative analgesia

Preoperative • Pediatric ( cong. heart .

Chest inf...) or geriatric ( syst. Dis. HPT.DM ..)

• Sedative • Anticholinergics &

Antiemetics Intraoperative

• Smooth induction propofol . Fentanyl . Sux or dep.ms.relax

• Tube or LMA + • avoid stress response • Ketamine avoided • Controlled ventilation• Smooth extubation

Postoperative • Analgesia • Nausea and vomiting

Open eye injury• Full stomach • Rapid sequence

induction • Aspiration

prophylaxis • Avoid injury of eye

by mask• Awake extubation Retinal surgery• Lenthy surg• GA preferred• Dark room • Don't use N2O

Regional anesthesia in ophth.surg

Patient selection Concent Examination of fascial n. Andextraocular ms. Preperation for GA Axial length <26 Full investigation Cardiopulmonary resuscitation Full monitors Sedation Sterilization Presence of anesthetist is essential

Types of regional Topical = drops Subconjunctival injection Intracameral = topical +injection in

anterior chamber Subtenon Extraconal = peribulbar Intraconsal = retrobulbar

• Primary gaze position safest • 2.5 ml needle + 2.5 ml solution• lateral 1/3 of lower balberal fissure infro-

temporal quadrent• Iside cone = rapid onset = spinal• Extraconal = slower onset = epidural • You cannot differentiate between both types• Direction of needle superior-medially• Both ways slight movement of needle to

confirm position + needle not attached to globe • After injection needle withdrawal + slight

pressure over globe • Additional fascial nerve may be needed with

intaconal

• Additional fascial nerve may be needed

• Different techniques • A- Van lint subcutanous

around outer canthus • B-O Brien midway

between tragus and lat orbital margin

• C- Nad Bahth injection near mastoid

Complication of local • Occulocardiac reflex • Chemosis, bruising• Retrobulbar hemorrhage• Globe penetration and perforation• Optic nerve damage and atrophy• Extraocular muscle malfunction and injury• Globe ischemia• Central spread Central Nervous System Spread

of Anesthesia = Brain stem anesthesia Loss of conc. Cardiovascular instability Cardiac arrest Vomiting

Hemiplegia Aphasia Convulsions Contralateral

extraocular ms. Palsy

Hemorrhage • Venous

Most common are venous, and bleeding is slowVenous hemo.do not ordinarily threaten vision, the consequences are less severe than arterial hem.and they require no intervention

• Arterialcan be more serious. within a few minutesproptosis and tight eyelids, ecchymosis, chemosis (i.e., conjunctival blood vessel engorgement), blood staining of periorbital tissues, lid swelling, and a dramatic increase in intraocular pressure.Late optic atrophy microvasculature of the optic nerve becomes occluded. A compressive retrobulbar hematoma may threaten retinal perfusion2 by causing central retinal artery occlusion.1