Treatment of Ocular Chemical Trauma
Immediate Decontamination: The Critical First Step
Begin irrigation immediately at the scene of injury—before any examination or history-taking—as rapid removal of the caustic agent is the single most important determinant of visual outcome. 1
Irrigation Protocol
- Start irrigation within seconds of exposure using copious amounts of tap water for a minimum of 15 minutes continuously 1, 2
- Tap water is the preferred initial agent because it is readily available and has been demonstrated to be effective for decontamination 1
- If immediately available, normal saline, Ringer's lactate solution, or commercial eye wash solutions are reasonable alternatives 1, 2
- Continue irrigation until a healthcare professional can measure the tear film pH and confirm it has returned to normal (pH 7.0-7.5) 2
Critical Safety Measures During Irrigation
- Avoid cross-contamination of the unaffected eye, other individuals, or surrounding areas with the caustic substance 1, 2
- Remove all contaminated clothing and jewelry to prevent trapping chemicals against the skin 1
- Wear personal protective equipment when exposure to the caustic agent is possible 1
- Assist patients in keeping their eyelids open during irrigation if needed 3
Special Chemical Considerations
Dry Chemical Exposures
- For dry chemicals such as sodium hydroxide, elemental sodium, or elemental potassium that react with water, first brush off as much powder as possible (dry decontamination) before beginning water irrigation 1
- This prevents exothermic reactions that could cause additional thermal injury 1
Specialized Chemical Agents
- Hydrofluoric acid and phenol require specialized decontamination approaches beyond water irrigation 1, 2
- For industrial chemical exposures, adhere to local guidelines or contact a regional poison center for chemical-specific treatment recommendations 1, 2
- Safety Data Sheets provide chemical-specific decontamination protocols 1
Determining When to Stop Irrigation
The definitive endpoint for irrigation is when the tear film pH returns to normal (7.0-7.5) as measured by a healthcare professional. 2
Common Pitfall: pH Measurement Errors
- Delays in obtaining tear fluid pH measurements can artificially increase the measured pH value 2
- Samples measured too quickly after irrigation can result in falsely neutral pH readings 4
- Perform a control litmus pH test on the examiner's own eye to verify the accuracy of testing materials and technique 4
- Errors can occur from difficulty matching paper with scale colors, drying of the paper, inadequate tear film samples, or faulty materials 4
Advanced Medical Care
All patients with ocular chemical injuries require immediate ophthalmologic evaluation after initial irrigation, as even with immediate treatment, concentrated or potent chemicals can cause significant injury requiring advanced medical care. 1
Immediate Referral Indications
- Any chemical eye injury after completing initial 15-minute irrigation 1, 5
- Industrial chemical exposures 2
- Persistent symptoms after irrigation 5
- Vision loss, irregular pupils, or eye bleeding 5
Contact Resources
- Regional poison control centers for expert guidance on severe cases and chemical-specific protocols 1, 3
- Local hazardous materials protocols for workplace exposures 1
Mechanism of Injury
The extent of ocular damage depends on: 1
- The mechanism and concentration of the chemical
- Depth of penetration into ocular tissues
- Volume of chemical exposure
- Duration of contact before irrigation begins
Alkali injuries are more common and typically more severe than acid injuries because alkalis penetrate deeper into ocular tissues. 6