Finally, this year Waldman published a study larger than the prior work in 2014.4 This was a well-done study of 1,576 patients with corneal abrasions, of which 532 were determined to be “simple” as opposed to “complicated.” The relative risks for ED return visit and fluorescein staining (both indications of persistent symptoms) were 1.67 and 2.53, respectively. However, when considering only simple corneal abrasions, the numbers neutralized to 1.16 and 0.77. Most important, the complications were too rare to model, and thus there was no evidence that the short-term use (24 hours) of non-dilute tetracaine was unsafe. Will our ophthalmology colleagues be satisfied? Past experience predicts future expectations.
Explore This IssueACEP Now: Vol 37 – No 09 – September 2018
A Change in Practice?
These data should suffice to put this question to rest. Unfortunately, dogma may create an irrational conviction to unfounded “facts.” For example, three ophthalmologists wrote a very critical rebuttal to Waldman’s 2014 study.5 “While tetracaine temporarily anesthetizes pain, its routine usage to treat traumatic corneal abrasions in an emergency department is dangerous and can lead to blinding ocular complications.”
What evidence did they offer to support this hysteria? None, except for one study about chloramphenicol ointment, which was used to establish a low rate of corneal ulcer (0.26 percent) from corneal abrasions in Nepal, reporting more complications in Waldman’s tetracaine group.6 However, none of Waldman’s patients ever developed corneal ulcers. The ophthalmologists also cited a case report of eight patients who developed corneal defects, stromal opacity, or ring-shaped infiltrates. However, only one patient was treated for a corneal abrasion while the others had more severe pathology and the mean duration of topical anesthetic use was 14.8 days ± 7.78 days.7
Their final evidence was from a 1990 article titled, “Topical Anesthetic Abuse.” Really? Is tetracaine a drug of abuse? This was a case report of six patients with complications, reportedly secondary to prolonged anesthetic use.8 Finally, perhaps their greatest criticism reflects a negative bias about emergency physicians. “The methodology used to diagnose corneal abrasions is ambiguous. None of the corneal evaluations were performed by an ophthalmologist, and some of the evaluations were not even done by a physician.”5 It is maddening to consider that in 2014, some ophthalmologists didn’t feel emergency physicians were qualified to diagnose corneal abrasions. Clearly, the evidence they were challenging was far superior to anything they presented.
With dogma as thick as fog, the only answer must be that the duration and volume of “evidence” must have shaped generations of ophthalmologists, resulting in the indiscriminate and irrational challenge of alternative perspectives, despite evidence supporting new thinking.