Incorrect solution causes chemical burn

Issue: October 2004

ByMarlane J. Brown, OD, FAAO

Marlane J. Brown, OD, FAAO [photo] Marlane J. Brown, OD, FAAO, is on staff in the Ophthalmology Department at the Regions Hospital Eye Clinic. She can be reached at Minnesota Eye Consultants, 710 East 24th Street, #106, Minneapolis, MN 55404; (612) 813-3621; fax: (612) 813-3636; e-mail: mjbrown@mneye.com. Dr. Brown has no direct financial interest in the products mentioned in this article, nor is she a paid consultant for any companies mentioned.

A patient called our clinic from Italy stating that he had instilled a drop of solution in his eye and it was burning badly. As our office is in Minneapolis, it was suggested that he seek medical care in Italy rather than travel home to see us for care.

He had been traveling overnight on a train. In the early morning, he went to the cramped bathroom, opened his toiletries bag and took out what he thought was Boston contact lens wetting solution (Bausch & Lomb, Rochester, N.Y.). He put one drop onto the contact lens and then placed the contact lens on his left eye. It began burning immediately, and he removed the contact lens. To attempt to soothe the burning, he instilled another drop of the solution directly onto the eye.

It was then that he noticed he was using Mycocide NS (Woodward Laboratories, Aliso Viejo, Calif.), a liquid nail fungicide, instead of Boston contact lens wetting solution. The bottles looked very similar.

Corneal, conjunctival abrasion

The patient traveled to a nearby emergency room and was treated with what he described as “steroid injections.” He was sent home with neomycin ointment to apply to the eye. He spent 2 days in a hotel room with a patch over the eye and then flew home.

The patient had developed a large corneal and conjunctival abrasion due to chemical burn. He was seen in our office 5 days after the incident.

At this first visit, his uncorrected vision was 20/200 at 3 feet. He was still photophobic and in pain. Normally, he wears a GP contact lens but had not tried to wear the lens for several days since the accident.

On slit-lamp examination, his cornea showed a superficial epithelial defect about 5 to 6 mm in diameter, surrounded by patchy areas of heaped up epithelium and diffuse punctate epithelial keratitis. Fluorescein staining was seen on the conjunctiva as well. The eyelids were hyperemic and edematous. The anterior chamber appeared clear.

The patient was asked to discontinue the neomycin ointment, because neomycin can cause a toxicity reaction. In addition, ophthalmic ointment can cause a dragging effect on healing epithelium and slow the healing. Ocuflox (ofloxacin, Allergan) was prescribed four times per day along with non-preserved artificial tears to be instilled every 30 to 60 minutes while awake.

Ocular history complications

The next day, slit-lamp exam showed significant improvement in the cornea, although his comfort and vision remained poor. The patient’s ocular history complicates the healing, as he is a post-radial keratotomy patient, with a history of poor epithelial healing. His best spectacle-corrected vision was normally 20/80, and he depended on a GP contact lens for best vision, due to irregular astigmatism.

At the 1-week visit to our office, his cornea appeared nearly clear with a few punctate epithelial stains remaining. By the 2-week visit, his cornea was as clear as it was prior to the trauma, and he was able to return to his post-RK contact lens wear.

The offending bottle of fungicide stated the only active ingredient was benzalkonium chloride. No other ingredients were listed on the bottle, although research indicated the solution also contains allantoin, described as a skin softener. Attempts to contact the Poison Control Center yielded no information on the solution. Later attempts to contact the company that makes the solution also yielded no response.

Similar incidents

Mycocide NS and Boston solution: The patient mistook a bottle of nail fungicide for his contact lens solution, resulting in a chemical burn.

Other incidents of inadvertently instilling the wrong solution into the eye are documented. Two cases of hospital staffers putting hemoccult developer into patients’ eyes, once instead of artificial tears and once instead of Timoptic (timolol maleate, Merck) were reported in the August 1988 issue of Archives of Ophthalmology (Tak Kam Ling R, Villalobos R, Latina M. Case reports: Inadvertent instillation of hemoccult developer in the eye. Arch Ophthalmol. 1998;106:1033-1034).

Another incident included an 85-year-old man with glaucoma and a colostomy. During a hospital stay, his stoma deodorant drops were inadvertently instilled into both eyes instead of topical glaucoma treatment. Despite immediate and intensive ocular irrigation, the deodorant drops, which had a pH of 5, caused severe chemical injury to both eyes, including loss of both corneal epithelia and 180° of limbal ischemia. Fortunately, he eventually made a full recovery (Wheeler J, Shah P. Minerva picture. BMJ. 2001;322:182).

Eye drops are often identifiable to patients by the color of their tops. We all know that red tops have some sort of dilating effect. Discussing treatment with patients on Timoptic becomes easier when we are able to tell them that the bottle has a yellow cap. But, this can be confounded when similar looking bottles contain very different solutions. The labels of these topical medications are small, which makes their identification more difficult, especially for many of our patients who have poor uncorrected vision.

Education is key, and providing a way for patients to identify their eye drops, whether it be contact lens solutions or postoperative medications, is challenging. Our clinic will use colored tape around the labels or caps to identify the correct bottle in poorly seeing patients. Perhaps we should do this for contact lens solutions as well.

Industry standards

Making eye drops look like eye drops and letting nothing else take the same shape would be ideal. Creating industry standards would be a tedious but definitive way to solve this dilemma. One editorial recommended that any non-ophthalmic preparations that could be mistaken for an eye drop have a black cap (Frenkel RE, Hong YJ, Shin DH. Misuse of eye drops due to interchangeable caps. Arch Ophthalmol. 1988;106:17).

Some of the known offending solutions include the above-mentioned hemoccult, this patient’s Mycocide and some otic preparations.

Now, I ask each patient what other medicines they take that might look like they are in an eye drop bottle. Sometimes, they have to go home and look in their medicine cabinets or their toiletries bag and call me back. This alerts them to the similarities and the possibilities of errors. Keeping the eye drops in a separate location or different bag may help. Instruct the patient to carry irrigating solution or artificial tears to flush their eye as soon as a mistake occurs.

As for my patient who used the foot fungicide instead of the contact lens wetting solution in his eye, he still carries both bottles in his toiletries bag.