Emergency management of pain caused by a corneal abrasion from a foreign body can be a challenge, particularly given the time constraints of treatment in the emergency department. Treatment strategies range from use of a standard opioid regimen to instillation of ophthalmic nonsteroidal anti-inflammatory drugs (NSAIDs) for pain control. Brown and associates outline an evidence-based medicine (EBM) approach to evaluate the effectiveness of ophthalmic NSAIDs in treating corneal abrasions. The exercise consists of four steps: (1) formulating the question, (2) searching for and selecting the best evidence, (3) analyzing the evidence and (4) applying the evidence.

A well-constructed clinical question is based on the acronym “PICO,” for which P represents stating the problem, I the intervention, C the comparison intervention (if necessary) and O the outcome(s) of interest. For a detailed listing of PICO elements applied to a patient with a corneal abrasion, see the accompanying table on page 2522. Given the construct of PICO, the final question in this situation is: “In patients with acute corneal abrasions treated in the acute care setting, will ophthalmic NSAIDs decrease pain as well as or better than placebo, oral analgesics or standard therapy without delaying healing?” Evidence was gathered using a MEDLINE database search combining the terms “corneal injuries” and “NSAIDs.” The initial search resulted in 29 articles, and this number was subsequently narrowed by a further requirement that the clinical trials be written in English. Of the five articles that resulted, only three actually addressed the problem. These studies were then evaluated for validity, size of treatment effect and other aspects that helped determine the usefulness of the results, such as adverse effects, cost and availability.

Ophthalmic NSAIDs offer a number of advantages and disadvantages in treating corneal abrasions. Among the advantages are good pain relief and lack of sedation when compared with opioids. Disadvantages include cost and burning on instillation. The advantages and disadvantages should be reconciled by involving the patient in the decision-making process.

The authors conclude that EBM involves practicing medicine by evidence and then combining the best evidence with the clinician's experience and the patient's rights, values and preferences. EBM exercises such as this one often create more questions than they answer.