Reducing Intraoperative Discomfort And Medication Use During Cataract Surgery Through Lower Intraocular Pressure Fluidics

To compare patient comfort and intraoperative medication requirements during cataract surgery performed at lower versus higher intraocular pressure (IOP), using a dual-pump fluidic platform (Unity VCS) and a single-pump system (Centurion Active Sentry, CAS), respectively.

Single-center, outpatient cataract surgery practice in the United States (Iowa).

This prospective, randomized, paired-eye study included 85 patients (170 eyes) undergoing sequential bilateral cataract surgery. The first eye was randomized to lower IOP using a dual-pump system (Unity VCS, 28 mmHg) or higher IOP using a single-pump system (Centurion Active Sentry, ≥60 mmHg), with the fellow eye receiving the alternate setting. The primary outcome was the need for intervention for breakthrough intraoperative discomfort. Secondary outcomes included VAS-reported discomfort, physiologic pain responses (blood pressure and heart rate), postoperative day-1 experience and preference surveys, time to discharge, and surgeon-rated experience on a 3-point scale (1=poor, 3=best).

Forty-eight eyes of 24 patients were included in this preliminary analysis. Breakthrough discomfort requiring treatment occurred in two cases in the higher IOP group and in none in the lower IOP group. Mean VAS discomfort scores favored lower IOP. Surgeon rated patient cooperation and overall intraoperative experience were improved with lower IOP. Five patients (2 in lower IOP group, 3 in higher IOP group) experienced a physiologic response to pain.  Eleven of the 16 patients reported that the low IOP setting was more comfortable, 8 of whom had the low IOP setting second. Postoperative day1 patient reported outcomes were comparable between groups.

Early findings suggest that cataract surgery performed at lower IOP using a dual pump fluidic system may enhance intraoperative comfort and reduce the incidence of breakthrough pain. When breakthrough pain occurred, it was limited to fluidics stages in the higher IOP group. Pain scores during fluidics stages favored the lower IOP setting, Physiologic pain responses were infrequent in both groups. The reduced incidence of pupil block at lower IOP may contribute to improved patient experience, supporting the role of fluidics optimization during phacoemulsification.