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 Pain Is Potentially Safe

Study objective To determine if the number of emergency department (ED) rechecks, persistent fluorescein uptake, ophthalmology referrals, or complications would be affected by the prescription of topical tetracaine for pain relief from simple corneal abrasions (SCAs). Methods This retrospective cohort study was conducted in an ED where policy change allowed physicians to use topical tetracaine hydrochloride 1% eye drops for 24 hours for pain treatment for patients with corneal abrasions. Outcomes were compared between patients who did or did not received tetracaine (adjusting for the propensity for treatment). Results Of 1,576 initial ED presentations, 532 were SCAs, with 1,044 deemed nonsimple corneal abrasions (NSCAs). Tetracaine was dispensed at the initial visit for 303 SCA presentations (57%) and inappropriately for 141 NSCA presentations (14%). There were no serious complications or uncommon adverse events attributed to tetracaine for all SCAs and NSCAs combined (0/459; upper 95% confidence interval [CI] 0.80%). The relative risks (RRs) of ED recheck and fluorescein staining were increased overall among patients who received tetracaine (RR 1.67, 95% CI 1.25 to 2.23; and RR 1.65, 95% CI 1.07 to 2.53 for recheck and staining, respectively). However, the relative risks for only SCAs receiving tetracaine was 1.16 (95% CI 0.69 to 1.93) and 0.77 (95% CI 0.37 to 1.62), respectively. Referrals to ophthalmology were significantly decreased for all patients (SCAs and NSCAs) dispensed tetracaine (relative risk 0.33; 95% CI 0.19 to 0.59). The number of complications was too small to permit modeling. Conclusion There was no evidence that up to 24-hour topical tetracaine for the treatment of pain caused by SCA was unsafe; however, CIs were wide and some increased risks were observed for NSCAs.