Chemical Eye Injury

Clinical assessment

History of chemical splash/exposure to the eye. Identification of the chemical agent (acid vs. alkali, specific agent) is helpful but not essential for initial management (irrigation!). Examination findings (pain, redness, corneal clouding, conjunctival changes). Assess severity based on corneal clarity and extent of limbal ischemia (blanching around cornea).

Investigations

• Visual acuity testing (may be difficult due to pain/swelling).
• pH testing: Check conjunctival fornix pH using litmus paper AFTER initial irrigation. Continue irrigation until pH normalizes (pH 7.0-7.4).
• Slit lamp examination (Specialist): Assess depth/extent of corneal damage, anterior chamber reaction, limbal ischemia.
• Intraocular pressure measurement (tonometry).

Diagnostic criteria

History of chemical exposure with ocular symptoms/signs. Severity graded based on corneal clarity and limbal ischemia.

Non-pharmacological management

• IMMEDIATE Copious Irrigation (MOST IMPORTANT STEP):
• - Start irrigation IMMEDIATELY at the scene if possible, continue en route and at facility.
• - Use sterile Normal Saline, Ringer's Lactate, or clean tap water if sterile fluids unavailable.
• - Irrigate continuously for at least 15-30 minutes, or longer for alkali burns.
• - Volume: Use large volumes (liters).
• - Technique: Evert eyelids, use eyelid speculum or Morgan lens if available to ensure thorough flushing of conjunctival fornices. Direct stream away from unaffected eye.
• - Check pH after initial irrigation, continue irrigating until pH is neutral (7.0-7.4) and stable for 15-30 mins after stopping irrigation.
• Remove any visible particulate matter (e.g., lime, cement powder) with moistened cotton swab WHILE irrigating.
• Eye Examination: Perform thorough exam AFTER adequate irrigation.
• Protective measures: Avoid rubbing the eye.

Pharmacological treatment

• Topical Anesthetic: (e.g., Tetracaine) 1-2 drops initially to relieve pain and facilitate irrigation/examination.
• Antibiotic Ointment/Drops: Broad-spectrum topical antibiotic (e.g., Chloramphenicol, Tetracycline ointment - UCG rec, Ofloxacin, Moxifloxacin) QID to prevent secondary infection, especially if epithelial defect present.
• Cycloplegic Drops: (e.g., Atropine 1% or Homatropine 5%) BID-TID to relieve ciliary spasm, reduce pain, and prevent posterior synechiae.
• Topical Corticosteroids: (e.g., Prednisolone acetate 1%) Used short-term (7-10 days) in moderate-severe burns under specialist guidance to reduce inflammation. Prolonged use can impair healing and increase infection/melting risk.
• Lubrication: Preservative-free artificial tears frequently for epithelial healing and comfort.
• Oral Analgesia: Paracetamol or NSAIDs for pain.
• Intraocular Pressure (IOP) Lowering Agents: If IOP is elevated (e.g., topical beta-blockers, alpha-agonists, carbonic anhydrase inhibitors - specialist management).
• Other potential treatments (Specialist): Ascorbate (Vitamin C) drops/oral, Doxycycline oral (matrix metalloproteinase inhibitor), Amniotic membrane transplantation, Limbal stem cell transplantation.

Monitoring

Close follow-up with ophthalmologist is essential. Monitor visual acuity, corneal healing, intraocular pressure, signs of infection or melting. Frequency depends on severity.