Is it safe to routinely send patients home with topical tetracaine from the ED after corneal abrasion? A retrospective chart review

Simple corneal abrasions heal quickly but can be quite painful and irritating. Topical anaesthetics work like magic at relieving the pain. But tradition has told us sending patients home with this medication is a no-no. Your eyeballs will rot and fall out…

But recent literature has suggested this is probably all a myth. A New Zealand RCT performed by Waldman et al. in 2014 supported the safety of topical tetracaine.

Waldman et al. has been on a roll down in Invercargill. Their RCT changed local practice in the ED and they started discharging patients with simple corneal abrasions with a take home pack of tetracaine (3 plastic 0.5ml commercially available vials or approximately 50 drops. They could use it as often as every 30 minutes for 24 hours)

They did a retrospective medical records review to see if this practice was safe.

During the study period, tetracaine was used 459 times for corneal abrasion. How many serious complications did they find?

None.

Sounds like a slam dunk. Send home patients with topical anaesthetic. Boy… that was easy.

Or maybe not…

To be fair, this is poor quality evidence. Retrospective record reviews suffer from poor quality data that was never collected with the intention to be included in a study. Much may be incomplete, missing or wrong.

In addition, the surrogate measures for “safety” are problematic. ED rechecks and ophthalmology clinic referrals were thought to suggest complications. But were they? We don’t know.

The authors conclusions and editors capsule summary are appropriately cautious. They mention wide confidence intervals, some increased risk for complicated corneal abrasions and large prospective studies are needed to confirm safety. Sure…

But it is probably true that no eyeballs went rotten or fell out… so I’m tempted to believe it. This may be poor quality evidence but it has face validity anyway. It also adds to an evolving body of literature that is pretty much telling us the same thing.

Send them home with topical anaesthetic… it’s ok.

Covering:

Waldman N, Winrow B, Densie I, et al. An Observational Study to Determine Whether Routinely Sending Patients Home with a 24-hour Supply of Topical Tetracaine from the Emergency Department for Simple Corneal Abrasion Is Potentially Safe. Ann Emerg Med 2017; article in press.