Effect of alpha-2-agonist premedication on intraocular pressure after selective laser trabeculoplasty

To determine the effect of alpha-2-agonist (AA) premedication (PM) on intraocular pressure (IOP) following selective laser trabeculoplasty (SLT).

Retrospective cohort study of all patients undergoing 360° SLT at an institution with two prevalent practice patterns consisting of SLT performed with PM and without premedication (NPM) with AA. The association between pre- and post-operative IOP was evaluated using a linear regression model in 49 (59%) PM and 34 (41%) NPM eyes.

The prevalence of IOP elevations up to 5 mmHg 1 h postoperatively was similar in both groups, occurring in 18% of PM and in 15% of NPM. Elevations above 5 mmHg were seen in 4% of PM and 8% of NPM (P = 0.732). After correcting for age, gender, diagnosis, number of medications, and preoperative IOP, the presence or absence of AA PM had no significant association with any postoperative IOP (P > 0.5).

The practice of using AAs before SLT and measuring IOP at 1 h has not been validated yet adds to expenses and workflow burden. Our retrospective study showed no significant correlation between PM and postoperative or longer-term IOP. IOP at 1 h should be measured in patients who cannot tolerate transient pressure elevations. Further studies are needed to elucidate this relationship.