Musculoskeletal, Skin & HEENT · Topic 12 of 14

Acute Eye Emergencies

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HEENT · acute eye emergencies

Acute Eye Emergencies

Sudden vision loss or a painful red eye is an emergency: irrigate chemical burns first, measure pressure, and call ophthalmology.

01 · Chemical burnIrrigate at least 30 min, until pH 7.0–7.2

02 · Angle closureIOP 40–80 mmHg, fixed mid-dilated pupil

03 · Think CRAOSudden painless monocular loss: stroke center

What causes acute vision loss

Vision loss over seconds to days is itself a red flag

Opacification

Corneal ulcerVitreous hemorrhage

Retinal disease

Retinal detachmentRetinal artery occlusion

Optic nerve and pathway

Optic nerve lesionsVisual pathway lesions

What you'll see

Painful red eye or painless vision loss: both are emergencies

Angle closure: severe eye pain and redness, colored halos

Angle closure: decreased vision, headache, vomiting

Angle closure: hazy cornea, fixed mid-dilated pupil measure IOP

CRAO: sudden, painless, severe monocular vision loss stroke center

CRAO: afferent pupillary defect, pale retina with cherry-red fovea

Retinal detachment, painless: sudden increase in floaters, photopsias

Retinal detachment: curtain or veil across the visual field urgent ophthalmology

Orbital cellulitis: proptosis, painful or reduced eye movement

Orbital cellulitis: decreased vision

Globe perforation: positive Seidel sign, misshapen pupil

Diagnosis & exam

Measure IOP, and in a corneal injury evert the lids and stain

Angle closure: measure IOP, usually 40–80 mmHg

Corneal injury: topical anesthetic, evert the lids, fluorescein with cobalt blue

Multiple vertical linear abrasions: foreign body under the upper lid

Fluorescein streaming from a corneal wound is a positive Seidel sign

Suspected perforation: order CT for intraocular foreign body

Suspected orbital cellulitis: image the orbits with CT or MRI

Chemical burn: normal conjunctival pH is 7.0–7.2

Merck's red-eye table states IOP usually over 30–35 mmHg; its angle-closure chapter gives 40–80 mmHg as typical.

Red flags

Chemical exposure to the eye irrigate first

Acute vision loss, seconds to days call ophthalmology

Seidel sign, misshapen pupil or high-risk mechanism shield + CT

Proptosis, painful or reduced eye movement, or decreased vision admit

Retinal artery occlusion with new headache or jaw claudication suspect GCA, steroids

Retinal artery occlusion with temporal artery tenderness suspect GCA, steroids

Ophthalmic corticosteroids in corneal abrasion contraindicated

Patching a corneal abrasion: no help, may raise infection risk no patch

Topical timolol: bronchospasm, bradycardia, fatigue, confusion weigh systemic risk

Weigh timolol's systemic effects in reactive airway disease or conduction disease.

Treatment

The first move, by emergency

Chemical burn: irrigate nowany solution, at least 30 min, until pH 7.0–7.2

→

Angle closure: lower IOP nowtopical drops + acetazolamide, then iridotomy

→

CRAO: refer to a stroke center nowcerebrovascular risk is increased

→

Orbital cellulitis: hospitalizeCT or MRI, ophthalmology, IV antibiotics

Chemical burnirrigate before anything else

Erythromycin 0.5% ointment Cycloplegic if needed

Irrigate with any available solution, including tap water; do not delay

Avoid further topical anesthetic. Only ophthalmology prescribes topical steroids (perforation risk)

Angle closurelower IOP immediately

Timolol, pilocarpine, brimonidine drops Acetazolamide 500 mg PO or IV

Acetazolamide 500 mg, then 250 mg every 6 hours; consider an osmotic agent

Definitive: laser peripheral iridotomy by ophthalmology

Orbital cellulitishospitalize, meningitis-dose IV

Ceftriaxone or cefotaxime Piperacillin-tazobactam Imipenem

Image the orbits, consult ophthalmology, start IV antibiotics

Add vancomycin if MRSA is prevalent or after trauma; metronidazole for dental sources

Preseptal cellulitiseyelid only

Amoxicillin-clavulanate Ampicillin-sulbactam IV

Outpatient amoxicillin-clavulanate only if orbital cellulitis is definitively excluded

Inpatients get IV ampicillin-sulbactam

Corneal abrasionointment, no patch

Erythromycin ointment Bacitracin/polymyxin B ointment Ciprofloxacin 0.3% ointment

Contact lens wearers need antipseudomonal coverage such as ciprofloxacin

Topical anesthetics are controversial; oral analgesics are the alternative

Globe perforationprotect the eye

Apply an eye shield, order CT, get emergent ophthalmology

GCA featureswith retinal artery occlusion

High-dose systemic glucocorticoids

New headache, jaw claudication or temporal artery tenderness

Details are on the headache red flags sheet

Moderate or severe burnafter irrigation

Consult ophthalmology

Surgery, narrow angles, mimics, foreign bodies, topical anesthetic

Orbital drainage or decompression: compromised visionalso suspected suppuration or foreign body, orbital or large subperiosteal abscess, or failure on antibiotics

Pupil dilation can trigger angle closure in narrow anglescaution with mydriatics and systemic dilators: scopolamine, alpha-agonists, anticholinergics

Examine the eyes in sudden headache with vomiting

Iridotomy on both eyes: the other eye has an 80% chance of an acute attack

Miotics such as pilocarpine work poorly when IOP exceeds 40–50 mmHg

Cavernous sinus thrombosis can mimic orbital cellulitiscranial nerve palsies, bilateral eye involvement and mental status changes point to it (see ENT emergencies)

Steel or iron left on the cornea for hours: rust ring, ophthalmology removes it

Corneal foreign body: spud or 25–27-gauge needle, always approach from the side

Optic neuritis: mild pain with eye movement, early afferent pupillary defectcentral field loss and abnormal color vision; gadolinium MRI to look for multiple sclerosis

Corneal abrasion: older teaching forbids any topical anestheticACEP now supports it for simple corneal abrasions for the first 24 hours

CRAO: no proven treatment

Effective CRAO treatment is lacking: the stroke team decides on thrombolysis

Refer immediately to a stroke center: cerebrovascular risk is increased

Within 24 hours, try lowering IOP: timolol 0.5%, acetazolamide 500 mg

IV thrombolysis within 4.5 hours is an individualized stroke-team decision

Thrombolysis evidence in CRAO remains limited and conflicting

In a 2026 NEJM phase 3 trial, tenecteplase within 4.5 hours did not beat aspirin (vision recovery 20% vs 24%), with more adverse events including one fatal intracranial hemorrhage. A 2021 AHA statement and a 2026 meta-analysis favor early IV thrombolysis. Merck also lists ocular massage; a 2026 neuro-ophthalmology review says massage, paracentesis and vasodilators show no benefit and may harm.

Alkali or acid burn?

Alkali penetrates deeper, so it is usually worse

Alkali: liquefaction necrosis, penetrates deeper

Acid: coagulation necrosis

After irrigation: evert the lids, sweep the fornices for trapped particles

Preseptal or orbital cellulitis?

Preseptal is confined to the eyelid: vision and eye movement stay normal

	Preseptal cellulitis	Orbital cellulitis
Eye movement	Normal	Painful or reduced
Proptosis	None	Present
Vision	Normal	Decreased
Treatment	Oral amoxicillin-clavulanate only if orbital is definitively excluded	Hospitalize; meningitis-dose IV antibiotics

Pearl

Chemical in the eye: irrigate before anything else, then check that the pH is normal.