BLUE DYE MIX-UP It's easy to mix up look-alike, sound-alike drugs such as methylene blue and trypan blue.

Of the many look-alike, sound-alike drugs in surgery, trypan blue and methylene blue might be the easiest to confuse. The result of such a mix-up can blind patients.

• Trypan blue. In cataract surgery, trypan blue is used to visualize the capsulorhexis during phacoemulsification in the absence of a red fundus reflex.
• Methylene blue. Some use this long-lasting tissue-staining dye to mark the location of the incision.

Methylene blue is, however, highly toxic to the eyes. As these 2 cases illustrate, accidentally injecting methylene blue into the eye instead of trypan blue can have disastrous consequences.

The cases
Last year in California, a 71-year-old man was undergoing cataract removal and insertion of an intraocular lens. The surgeon requested VisionBlue (trypan blue) to stain the lens capsule. The surgical tech handed her a syringe, which the surgeon injected into the eye. When the surgeon looked at the eye in the operating scope, she found that the entire area was stained an opaque, dense blue.

Instead of VisionBlue, the tech had handed her methylene blue. Despite multiple irrigations with saline, the eye remained opaque. The patient was transferred to another facility for a possible corneal transplant, but the outcome is unknown.

The nurse who handed the syringe to the surgical tech reportedly thought the surgeon asked for methylene blue. Since the nurse couldn't find the right receptacle on the table for methylene blue, she drew it up into a syringe and handed it to the surgical tech, noting that all "you need is a few drops" — which is true when you use methylene blue to mark the location of the incision. The surgical tech incorrectly labeled the syringe as VisionBlue before handing it to the surgeon.

This isn't the first time this has happened. An almost identical case in North Carolina from almost 6 years ago just resulted in a $1.5 million malpractice award. The patient was undergoing cataract surgery when the ophthalmologist ordered VisionBlue to stain the capsule so the cataract could be removed, and instead was given methylene blue. Both the nurse and surgical tech testified that they announced methylene blue, but the surgeon apparently never heard that. The patient became permanently blind and developed glaucoma in that eye.

Prevent the problem
So how do you stop such a mix-up from happening at your facility? While it's important to have verification of the dye and labeling of the syringe by 2 qualified personnel, this is about more than miscommunication. It's clear there is a system issue here.

The blues are a LASA (look-alike, sound-alike) drug pair. If your center stocks both of these drugs, it's important to include these on your LASA list and discuss them during staff orientations, annual competencies and departmental meetings.

If your center only does eye cases, you probably don't even need to carry methylene blue, eliminating the risk. But if you do carry both, there are steps to take to make sure these mix-ups don't happen at your facility. If you have a legitimate need to carry methylene blue — which can be used as a staining agent or dye in a variety of procedures, among other things — clearly differentiate the two. Put "not for eye cases" on methylene blue, and consider "Tall man" lettering for both, for example methylene blue and trypan blue (make sure this doesn't interfere with other drugs you stock).

Also, be sure to store them separately. Even better, have an "eye room" or automated dispensing cabinet to store all medications and materials for eye surgeries, being sure methylene blue is not included in those areas.

Many ophthalmologists call the dye by its brand name, VisionBlue, which could be confusing to a circulating nurse who's unfamiliar with cataract surgeries and not told about the differences between the drugs beforehand. Hold a pre-op briefing, no matter how "routine" the surgery, where the surgeon can discuss VisionBlue and whether he expects to use it. VisionBlue isn't used in all cataract cases, so when a surgery is going along smoothly and the dye is needed suddenly, it can put stress on an unprepared staff.

5 practical pearls
Other ways to prevent a mix-up:

• Clearly label syringes. Remind staff that all filled syringes in the OR must be clearly labeled with their contents.
• Audit drug stocks. Periodically audit drug stocks in the OR to make sure that methylene blue hasn't snuck back to where it doesn't belong.
• Follow a "hear-back" system. When a nurse hands the surgeon the drug, he should repeat its name back to the nurse (Nurse: "This is the VisionBlue." Doctor: "Okay, this is the VisionBlue.").
• Be aware. This isn't the only blue-dye confusion. Retinal surgeons sometimes use a dye called MembraneBlue during vitrectomy surgery to visualize membranes and the vitreous. If accidently used during cataract surgery, it could damage the cornea.
• Educate your staff. Discuss these 2 cases with your staff. There's nothing like an employee hearing about a case and thinking Wow, that could happen here to make her follow proper procedure.