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.

Topical tetracaine used for 24 hours is safe and rated highly effective by patients for the treatment of pain caused by corneal abrasions: a double-blind, randomized clinical trial.

OBJECTIVES: The objective of this study was to test the hypothesis that topical tetracaine would be safe to use for 24 hours and would not affect corneal healing, that patients would experience more pain relief, and that patients would perceive tetracaine to be more effective than saline eye drops for the treatment of pain caused by corneal abrasions. METHODS: The study was a 12-month, prospective, double-blind, randomized trial of tetracaine versus saline set in the emergency department (ED) of a regional tertiary care teaching hospital. A total of 116 patients presenting with uncomplicated corneal abrasions were included in this study. The intervention was either undiluted, preservative-free, topical tetracaine hydrochloride 1% or saline, applied up to every 30 minutes while awake for 24 hours. Main safety outcome measures were repeat ED examinations at 48 hours with fluorescein staining and slit-lamp examination, 1-week and 1-month telephone interviews with additional examinations as needed, and monitoring of charts for complications. Secondary outcome measures were 100-mm visual analogue scale (VAS) pain scores recorded every 2 hours while awake for 48 hours and patient-perceived overall effectiveness using a numeric rating scale (NRS) of 0 to 10 obtained during telephone interviews. RESULTS: At least one follow-up encounter was completed on each of the 116 patients. No complications specifically attributed to topical anesthetic use occurred in the 59 patients in the tetracaine group, and the binomial probability confidence interval (CI) of this occurring is 0 to 6.1. There was no significant difference in corneal healing as measured by the percentage of patients with persistent fluorescein uptake at 48 hours between the two groups (23.9% vs. 21.3%, difference=2.6%, 95% CI=-14% to 20%, p=0.761) or persistent symptoms at 48 hours (21.7% vs. 21.3%, difference=0.4%, 95% CI=-16% to 17%, p=0.957). There was no clinical difference in VAS pain scores between the groups. Patients in the tetracaine group rated the study drugs' overall effectiveness significantly higher on the NRS (7.7 vs. 3.9) compared to patients in the saline group (difference=3.9, 95% CI=2.4 to 5.3, p<0.0005). CONCLUSIONS: Topical tetracaine used for 24 hours is safe, and while there was no significant difference in patient VAS pain ratings over time, patient surveys on overall effectiveness showed that patients perceived tetracaine to be significantly more effective than saline.

Seizure caused by dermal application of over-the-counter eucalyptus oil head lice preparation.

Natural plant oils such as eucalyptus are common worldwide in non-prescription natural health products. Oral ingestion of eucalyptus oil is well known to produce neurological symptoms and seizures; however, its dermal use is presumed to be safe. We describe a brief, self-limited, tonic-clonic seizure in a healthy 4-year-old girl following dermal exposure to eucalyptus oil as directed for treatment of head lice. Initial symptoms were vomiting, lethargy, and ataxia followed by a grand mal seizure. Recovery occurred rapidly after the skin was washed. Health care providers should be aware that eucalyptus oil toxicity may occur with dermal exposure and should report additional cases.