Discharge with topical corneal anaesthetic: Yes, you can

Topical proparacaine .05% (usual concentration is .5%) 2-4 drops to affected eye as often as needed for pain. Safe and effective in 15 patients.

God bless Dr. Ball et al, and god bless Canada, where medical decision-making is driven by concerns other than fear of litigation.

Now, we need a larger study. And how will I discharge a patient with dilute proparacaine?

CJEM 2010;12(5):389-94

Objective: Dogma discourages the provision of topical anesthetics to patients with corneal injuries discharged from the emergency department because of the toxicity of concentrated solutions. We compared the analgesic efficacy of dilute topical proparacaine with placebo in emergency department patients with acute corneal injuries.

Methods: We conducted a prospective randomized controlled trial of adults with corneal injuries presenting to one of 2 tertiary care emergency departments in London, Ont. Patients were randomly assigned to groups receiving either 0.05% proparacaine or placebo drops as outpatients and were followed up to heal- ing by a single ophthalmologist. Our primary outcome was pain reduction as measured on a 10-cm visual analog scale.

Results: Fifteen participants from the proparacaine group and 18 participants from the placebo group completed the study. The mean age of the patients was 38.7 (standard deviation 12.3) years and the majority were male (85%). Pain reduction was significantly better in the proparacaine group than in the placebo group, with a median improvement of 3.9 (interquar- tile range [IQR] 1.5-5.1) cm on the visual analog scale versus a median improvement of 0.6 (IQR 0.2-2.0) cm (p = 0.007). The proparacaine group was more satisfied (median level of satis- faction 8.0 [IQR 6.0-9.0] cm on a 10-cm visual analog scale v. 2.6 [IQR 1.0-8.0] cm, p = 0.027). There were no ocular compli- cations or signs of delayed wound healing in either group.

Conclusion: Dilute topical proparacaine is an efficacious analgesic for acute corneal injuries. Although no adverse events were observed in our study population, larger studies are required to evaluate safety.

Picture credit: Rakesh Rocky http://www.flickr.com/photos/22905496@N07/4259910413/