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Back to Basics: Ocular Chemical Burns

If time allows, check an initial ocular pH. This is always done in the fornix, the space between the inferior lid and the conjunctiva. The Morgan Lens must first be flushed with saline or prepared with proparacaine drops – never insert the lens dry. Proparacaine can also be placed on the eye directly prior to Morgan Lens insertion (patient may also need systemic analgesia). Run saline wide-open for 30 minutes, wait 1-2 minutes, then recheck the pH. Normal ocular pH is 6.5 to 7.5, thus if not in this range irrigation must continue for another 30 minutes. Sometimes this process may take hours and require up to 10 liters of fluid. Severe alkaline burns should be irrigated for 2-3 hours after…

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 How to manage chemical eye injuries

Alkalis are responsible for the most severe chemical injuries. Because acids instantly precipitate tissue proteins, a barrier is formed which prevents further ocular penetration. For this reason, acid burns are often well-demarcated and superficial – this is called coagulative necrosis. Alkalis, on the other hand, can cause extensive and penetrating eye injuries due to their ability to saponify fatty acids

 Quickly Douse Chemical Burns

Alkali agents (pH of 10 or greater) such as ammonia (found in cleaning agents, fertilizers and refrigerants), lye (drain and oven cleaners, air bags), magnesium hydroxide (in firework sparklers, flares) and lime (in plaster, mortar, cement, white wash) are lipophilic and penetrate the corneal stroma through saponification of fatty acids in cellular membranes. Once stromal tissue is damaged, proteolytic enzymes are released that furthers tissue damage, also known as liquefactive necrosis.

 The Eye In Chemical

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.

 Tips for Tots: Ocular Chemical Burns

Intranasal versed or fentanyl are quick, non-invasive, and effective options for anxiolysis and analgesia. Intranasal versed is dosed at 0.3 to 0.5 mg/kg. Intranasal fentanyl, which can be as effective as IV morphine, is dosed at 1.5 mcg/kg, with repeat dosing of 0.5-1.5 mcg/kg every 15 minutes, and is best used in patients over 3 years of age

Articles of Interest

Riot Control Agents

Copious H20/saline irrigation with Morgan Lens or Nasal Cannula.

Super Glued Shut

The adhesive will attach itself to the eye protein and will disassociate from it over time, usually within several hours. Periods of weeping and double vision may be experienced until clearance is achieved. Use of water to wash eyes repeatedly may assist in aiding more rapid removal of the adhesive.

Acute management of ocular chemical burns: A review

Ocular chemical burns are true ophthalmic emergencies produced by chemical agents when they come into contact with the ocular surface.

Approach to Ocular Trauma

Alkaline agents cause severe injury as they lead to liquefactive necrosis, which allows for deep intraocular penetration. In contrast, acids cause coagulative necrosis which protects the eye from deeper chemical penetrations.

Chemical Burns

If the chemical composition of the insulting agent is unknown and cannot be identified poison control can be contacted for more information. Items commonly causing injury to eye are listed below.

Managing chemical eye injuries:

Chemical burns to the eyes are potentially devastating for the individuals concerned and are regarded as ophthalmic emergencies. It is estimated that between 7 and 10 per cent of eye injuries are caused by chemicals

Ocular chemical injuries and their management

Once history of chemical exposure is obtained chemical should be identified if possible, but this should but delay treatment. Immediate treatment should include copious irrigation prior to ophthalmic evaluation irrigation with isotonic saline or lactate ringer solution should be performed and sometimes irrigating volumes up to 20 L or more is required to change pH to physiological levels(pH testing should be done).

Resources

Morgan Lens Insertion

Management of chemical burn to the eye with Morgan Lens Insertion.

EyeWiki

Irrigation is the cornerstone of managing chemical burns and should be initiated by by bystanders and continued as transfer of care takes place between EMS, ED physicians, and the ophthalmologist. Early irrigation is critical in limiting the duration of chemical exposure. The goal of irrigation is to remove the offending substance and restore the physiologic pH. It may be necessary to irrigate as much as 20 liters to achieve this.

StatPearls

Burns of the eye and ocular adnexa can be divided into two general categories, thermal and chemical. There are important distinctions between these two categories in how the injury progresses immediately after the injury. Tissue damage from thermal burns quickly abates once the heat energy is no longer in contact with the patient or after the source loses its thermal energy.