Symptomatic ocular exposures involve either immediate or delayed onset of eye discomfort accompanied by itching, tearing, redness, photophobia, blurred vision, and/or FB sensation. Conjunctival injection or chemosis may be seen. Exposure to defensive sprays or riot-control agents (eg, Mace or tear gas) causes immediate onset of severe burning, intense tearing, blepharospasm, and nasal and oropharynx irritation.
Management and Disposition
Begin copious irrigation immediately at the scene. Ubiquitously available, tap water is appropriate initially; switch to lactated Ringer’s or normal saline when available to limit corneal edema from hypotonic water. Acute caustic exposures are triaged to immediate treatment. Determine the conjunctival sac pH with a broad-range pH paper without delaying treatment. Continue irrigation until achieving a tear film pH of 7.4. Topical anesthetic drops permit examination and facilitate irrigation. Evert upper lid conjunctiva to examine for concretions. Alkali exposures penetrate deeper into tissues, causing more severe injury (liquefaction necrosis). Acids are less damaging (coagulation necrosis), which creates a barrier to further penetration. The exception is hydrofluoric acid, which acts as an alkali exposure.
Irrigate liberally after all exposures. Many chemicals merely cause irritative symptoms; however, some may also denude the corneal epithelium and inflame the anterior chamber. Perform slit-lamp examination to document corneal epithelial defects or anterior chamber inflammation. Cycloplegics may reduce ciliary spasm and pain. Address tetanus status.
Alkali Burn. Diffuse opacification of the cornea occurred from a “lye” burn to the face. (Photo contributor: Stephen W. Corbett, MD.)
Immediate onset of severe symptoms calls for immediate treatment and should prompt consideration of alkali or acid exposure.
Prolonged (up to 24 hours) irrigation may be needed for alkaline exposures.
Concretions from the exposure agent may form deep in the conjunctival fornices. Removal is critical to prevent ongoing injury.
A Morgan lens or other eye irrigation system is ideal for effective treatment as blepharospasm severely limits effectiveness of intravenous tubing alone.
Alkali Burn. Diffuse fluorescein uptake of the entire cornea is seen from an alkali exposure. (Photo contributor: Sarah M. Escott, MD.)
Caustic Burn Adhesions (Symblepharon). Scarring of both palpebral and bulbar conjunctivae results in severe adhesions between the lids and the globe. (Photo contributor: Arden H. Wander, MD.)