When can eye irrigation be discontinued in a patient with chemical exposure?

Management of Eye Irrigation After Chemical Exposure

Eye irrigation should be continued until a healthcare professional evaluates the injury and determines that the pH of the eye has returned to normal. 1

Initial Management of Chemical Eye Exposure

• Decontamination by irrigation should be performed immediately after chemical exposure to the eyes to minimize tissue damage 1
• Use continuous, large volumes of clean water for irrigation of chemical eye injuries 1
• Unless otherwise recommended by local guidelines, irrigation with a copious amount of tap water for at least 15 minutes should be performed 1
• When providing first aid for chemical eye injury, avoid contaminating other individuals, areas, or the unaffected eye with the caustic substance 1

Irrigation Solutions and Technique

• Tap water is effective and readily available for emergency eye irrigation 1
• If immediately available, eye irrigation with normal saline, Ringer's lactate solution, or a commercial eye wash solution is reasonable 1
• Commercial eye irrigation solutions may result in less severe eye injury and be more comfortable than other irrigation fluids 1, 2
• Some patients may need assistance maintaining open eyelids during irrigation 1, 3

Determining When to Stop Irrigation

• The definitive endpoint for irrigation is when a healthcare professional evaluates the injury and determines that the pH of the eye has returned to normal 1
• The length of time the chemical remains in contact with the eye determines the severity of the injury, making immediate and thorough irrigation essential 1, 3
• Although 15 minutes of continuous irrigation appears effective in many cases, more severe exposures may require longer irrigation 1, 4
• For alkali injuries in particular, persistently high pH levels may be present even after substantial irrigation, requiring continued treatment 1, 4

Special Considerations

• For industrial chemical exposures, adhere to local guidelines or recommendations from a poison center 1
• Some chemicals such as hydrofluoric acid and phenol may require specialized decontamination approaches beyond water irrigation 1, 5
• Dry chemicals like sodium hydroxide should be brushed off before irrigation to prevent exothermic reactions with water 1, 6
• Consider using a control pH test (testing the examiner's eye) if there are concerns about the accuracy of pH measurements 4

Common Pitfalls to Avoid

• Delaying irrigation - immediate decontamination is critical to minimize tissue damage 1, 3
• Stopping irrigation too early before pH has normalized, especially with alkali injuries which can continue to penetrate tissues 1, 4
• Cross-contaminating the unaffected eye during treatment 1
• Relying solely on a specific irrigation duration rather than pH normalization as the endpoint 1, 4