First-Day Intraocular Pressure Spikes after Phacoemulsification Cataract Surgery Among Patients Taking Tamsulosin

Abstract

Purpose : Transient intraocular pressure (IOP) spikes after cataract surgery are well documented; however, subgroups of patients predisposed to first-day IOP spikes need to be identified. Transient IOP spikes can cause intraocular pain, ischemic optic neuropathy and, in patients with glaucoma, progressive visual field loss. A retrospective, observational clinical study was performed to assess first-day intraocular pressure after phacoemulsification cataract surgery in patients taking tamsulosin hydrochloride at the time of surgery.

Methods : Using registry data from the University of Colorado Health Eye Center, data from patients who underwent phacoemulsification cataract surgery with intraocular lens implantation between January and August 2014 (n=630 patients) were analyzed. Patients taking tamsulosin at the time of surgery were included as cases, while patients with no history of Flomax use were used as controls. The primary outcome measure was a first-day postoperative IOP spike, defined as either 1) an IOP increase ≥ 10 mmHg compared to baseline or 2) a first-day postoperative IOP > 30 mmHg. A multivariable generalized linear model with repeated measures was used for analysis. Patients who underwent cataract surgery combined with another procedure, had a traumatic cataract or did not have IOP measured on postoperative day one were excluded. Analysis was performed in SAS 9.4.

Results : Of the 926 (n=630 patients) eyes included in the analysis, there were 52 eyes in the tamsulosin group and 874 control eyes. The mean ± standard deviation first-day postoperative IOP was 19.2 ± 9.4 mmHg in the tamsulosin group and 15.6 ± 4.8 mmHg in the control group (p<0.0001). An IOP increase ≥ 10 mmHg or IOP spike > 30 mmHg after cataract surgery occurred in 17.3% and 9.6% of eyes in the tamsulosin group versus 3.3% and 1.4% in the control group, respectively. After adjusting for a history of glaucoma and the use of a Malyugin Ring®, suture, and Iopidine® during surgery, patients on tamsulosin were 4.4 [95% CI: 1.5-12.7, p=0.007] and 5.7 [95% CI: 1.5-21.9, p=0.01] times more likely to have an IOP increase ≥10 mmHg or IOP spike > 30 mmHg, respectively.

Conclusions : Patients on tamsulosin have an increased risk of a first-day IOP spike after phacoemulsification cataract surgery. Future studies are needed to identify ways to mitigate this risk in order to prevent complications related to an increased IOP.

This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.