The Eye in Chemical

aka Ophthalmology Befuddler 019

A 45 year-old is rushed into the emergency department by the triage nurse. He was working at a building site and got cement into his eyes.

Questions

Q1. What is the likely diagnosis?

Chemical injury to the eye — cement contains lime, so this is a potential alkali injury.

Q2. What is the first thing that should be done in this setting?

Suspected chemical injury to the eyes is a true ocular emergency.

Start irrigation of the affected eyes with water even before examining the eyes (unless perforation is suspected).

Q3. What are the features to look for on history and examination?

History

  • What chemical was involved?
    (alkaline chemicals are particularly dangerous)
  • When did the exposure occur?
  • Was any first aid administered and when?
  • Symptoms? e.g loss of vision, pain, redness, tearing.
  • Associated injuries? e.g. skin exposure

Examination

  • Measure the pH — stop irrigation for 1 minute to use litmus paper to sample fluid from the forniceal space.
  • Visual acuity — may be decreased
  • Slit lamp
    Cornea
    — Look for corneal clouding.
    Corneal epithelial defects range from scattered superficial punctate keratopathy (SPK), to focal epithelial loss, to sloughing of the entire epithelium.
    Other features
    may be present —
    hyperemia, chemosis, eyelid edema, hemorrhages, skin burns and an anterior chamber reaction.
    Assess the degree of vascular blanching, particularly at the limbus, this correlates with severe chemical injury.
  • Funduscopy — If alkali has penetrated the sclera there may be retinal necrosis.
  • Tonometry — secondary glaucoma may occur

Sometimes epithelial defects from chemical burns are slow to take up fluorescein and repeated application may be necessary. If the epithelium has sloughed off leaving a denuded Bowman’s membrane fluorescein uptake may be very limited.

Q4. List examples of chemicals that may cause chemical injury to the eye? Which are more harmful?

Alkaline chemicals are particularly harmful to the eye as they cause coliquative necrosis.

Alkalis include:

    • lime, mortar and plaster, drain cleaner, oven cleaner, ammonia

Acids (which cause coagulative necrosis) include:

    • toilet cleaners, battery fluid, pool cleaners.

Neutral chemicals are treated similarly in the first instance and include:

    • solvents, detergents, aerosols and irritants, e.g. mace, pepper spray.

Q5. What is the management of this man’s condition?

Copious irrigation — for at least 30 minutes, usually about 3L of normal saline or other neutral fluid. Topical anesthesia is often required and should be administered early.

Ideally this should be started as soon as possible following the injury, i.e. prehospital. Contact the poisons centre for advice if further information on the chemical is needed.

Further management includes:

  • analgesia (usually oral) and cycloplegics
  • frequent use of preservative-free artifical tears
  • treatment of secondary glaucoma
  • daily review until the corneal defect has healed, after which steroids may be used by an ophthalmologist to reduce inflammation.
  • Severe chemical burns may require more specialised therapies (e.g. debridement, collagenase inhibitors, ascorbate or citrate for alkali burns, even stem cell transplantation from the contralateral eye) and hospitalisation may be required.

Q6. What is the end-point for irrigation in this setting?

Use litmus paper to check that the pH of the tears have returned to normal (about pH 7.5) after each litre of fluid. Check the other eye or your own for comparison if in doubt. Following (or during) irrigation consult an ophthalmologist urgently.

As soon as you’ve got your cemented eye out of the department you check the triage note of the next patient to be seen: “Eye glued shut with superglue”.

Q7. How will you manage your new patient?

  • If the eyelids are glued together, separate them gentle traction. If necessary trim the lashes.
  • Carefully remove the following with fine forceps to reduce the risk of corneal injury:
    • misdirected lashes
    • hardened glue that may rub on the cornea
    • glue stuck to the cornea
    • Treat epithelial defects as corneal abrasions.
  • If there is glue stuck to the lids or lashes that does not require urgent removal warm compresses qid can be applied to loosen the glue.
  • Arrange ophthalmology follow up for the next day.

References

  • Ehlers JP, Shah CP, Fenton GL, and Hoskins EN. The Wills Eye Manual: Office and Emergency Room Diagnosis and Treatment of Eye Disease (5th edition). Lippincott Williams & Wilkins, 2008.
  • Marx JA, Hockberger R, Walls RM. Rosen’s Emergency Medicine: Concepts and Clinical Practice, 7th edition (2009) Mosby, Inc. [mdconsult.com]
  • NSW Statewide Opthalmology Service. Eye Emergency Manual — An illustrated Guide, 2007. [link to free pdf]
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Comments

  1. merle says

    our friendly opthalmology people tell me in cases of superglue (or dermabond) in lashes, applying chlorsig ointment to lashes does a good job of loosening glue. Apparently chlorsig in various forms fixes everything opthalmological.

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