Patching for Corneal Abrasions?

Clinical Question

Is patching an effective treatment for simple corneal abrasions?

Evidence-Based Answer

Patching is not beneficial for the treatment of simple corneal abrasions as measured by time to healing, complete healing rates at 24 to 48 hours, or pain.

Practice Pointers

Corneal abrasions are superficial defects of the corneal epithelium that most commonly result from mechanical injuries to the cornea. Experts have long recommended patching (occlusion of the affected eye) for the treatment of simple abrasions; however, recent studies have questioned this traditional guidance.1

Eleven prospective randomized or quasi-randomized controlled trials were identified that studied the effectiveness of patching as measured by corneal healing in children and adults with corneal abrasion. All trials had two treatment groups with participants randomized to wear a patch for 24 hours or no patch; both treatment groups received variable dosing regimens of topical medications, including topical antibiotics, steroids, and cycloplegic eye drops.

Five trials measured the number of participants with complete healing (defined by no fluorescein staining) on each day of follow-up; two trials measured mean time to healing; and six trials measured percentage of healing or abrasion dimension sizes at each day of follow-up. Secondary outcomes measured in the trials included pain scores, analgesia use, treatment compliance, and ability to complete activities of daily living. Three trials mentioned short-term adverse events, and four trials reported long-term complications and follow-up two to seven months after the corneal abrasion. Overall, the studies were rated as being of poor quality because of uncertain adequacy of randomization, lack of intention-to-treat analyses, and high drop-out rates.

Meta-analysis of seven trials reporting complete healing rates on the first day of follow-up showed that more participants in the no-patch group had complete healing (risk ratio = 0.89; 95% confidence interval, 0.79 to 0.99). When the two quasi-randomized trials were excluded from the pooled analysis, the difference in complete healing rates between the groups was nonsignificant. Pooled analysis of studies reporting complete healing rates at day 2 and day 3 of follow-up showed no significant difference between the patch and no-patch groups. Analysis of six studies showed no significant difference between the patch and no-patch groups in the mean number of days to healing.

The nine trials measuring pain had conflicting results: two studies found less pain in the no-patch group, three studies found less pain in the patch group, and four studies found no significant difference. No differences were found in analgesia use, activities of daily living measures, patient compliance, presence of symptoms (e.g., photophobia, tearing, foreign-body sensation, blurred vision), use of mydriatic drops, or complications.

Adverse effects of patching include a loss of binocular vision while the patch is in place, which renders activities requiring depth perception (e.g., walking, driving) challenging. One study involving children showed that those in the patch group had significantly greater difficulty walking than those in the no-patch group.

This review addresses abrasions of less than 0.02 square inches (10 mm2); treatment of larger abrasions has not been adequately addressed.

Beta-Blocker Use in Patients with COPD

Clinical Question

Are beta blockers safe in patients with chronic obstructive pulmonary disease (COPD)?

Evidence-Based Answer

In 20 studies of cardioselective beta blockers in patients with COPD, participants had no adverse pulmonary or respiratory effects. Because of their salutary cardiovascular effects, cardioselective beta blockers should not be withheld from patients with COPD.

Practice Pointers

Beta blockers reduce mortality in patients with ischemic heart disease, heart failure, acute coronary syndrome, myocardial infarction, or hypertension.1,2 However, COPD often is cited as a contraindication to beta-blocker therapy.3,4 Concern about inciting acute bronchospasm with these agents often leads physicians to avoid using them in patients with COPD and life-threatening coronary artery disease.

In 2001, a systematic review reported that cardioselective beta blockers did not have any deleterious effects in patients with reversible airway disease.5 In 2005, the same researchers focused on patients with COPD because these patients are more likely than those with asthma to have underlying ischemic heart disease and therefore may benefit from beta-blockade.

The researchers found 20 trials evaluating the use of beta blockers in patients with COPD: 11 studies with a total of 131 patients evaluating single-dose treatment, and nine studies with a total of 147 patients evaluating treatment of a longer duration. Most of these studies were small, with averages of 12 and 16 patients in the single- and continued-treatment groups, respectively. Trials were included in the analysis if: (1) forced expiratory volume in 1 second (FEV1) was reported at rest; (2) the trials were randomized, controlled, and single- or double-blinded; and (3) participants met the American Thoracic Society definition of COPD or demonstrated a baseline FEV1 of less than 80 percent. The authors evaluated only cardioselective beta1 blockers (e.g., atenolol [Tenormin], metoprolol [Toprol], bisoprolol [Zebeta], acebutolol [Sectral]) because these were most often used in clinical practice.

There was no reduction in FEV1 or increase in respiratory symptoms in patients with COPD given cardioselective beta blockers in single or continued treatment. Four trials also demonstrated no adverse effects in the FEV1 treatment response to beta2 agonists in those patients given beta blockers.

This meta-analysis was limited by small study size, inclusion of only published literature, possible publication bias, and non-delineated randomization in many of the studies. In addition, 80 percent of the patients were men. However, in light of their proven mortality prevention, the benefit of cardio-selective beta blockers in patients with COPD who present with an acute coronary syndrome seems to outweigh the perceived risks.