Less Discomfort And Less Pharmacology: Cataract Surgery At Physiologic Intraocular Pressure - Breakthrough Discomfort And Surgeon Experience

To investigate whether phacoemulsification at physiologic (low) intraocular pressure (IOP) vs high IOP impacts patient discomfort, the incidence of breakthrough pain and the surgeon experience.

Wolfe Surgery Center. West Des Moines, Iowa. United States.

Prospective, randomized, paired-eye design of 130 eyes in 65 patients undergoing cataract surgery. First eye randomized to high (65mmHg) or low (24 mmHg) intraoperative IOP setting, contralateral eye received other IOP setting. Patient, surgeon, anesthesiologist and post-operative technicians blinded to study group. Primary outcome was the proportion of patients requiring treatment for breakthrough discomfort and additional cost. Secondary endpoints included physiologic (BP, heart rate) responses to pain, incidence of reverse pupillary block, and surgeon assessment of experience on a scale of 1 (poor) to 3 (best). Long axial length sub-analysis was also performed.

No patients in the low IOP group required breakthrough pain medication (0% v 15%, p=0.001) and had a lower incidence of reverse pupillary block (12% vs 32%, p=0.007) when compared to the high IOP group. The average cost of additional anesthesia per patient was lower in the low IOP group ($0 v $3.46, p=0.003). No differences in physiologic pain responses with heart rate and blood pressure were detected. Surgeon experience (2.98 v 2.62, p<0.001) was better in the low IOP group compared to the high IOP group. In the 47 eyes >24.5mm, differences in patient cooperation (p=0.005) and surgeon experience (p=0.002) persisted, but only 2 patients required breakthrough medication, making comparison difficult.

Low IOP settings during phacoemulsification did not require additional medication for breakthrough discomfort and resulted in less reverse pupillary block, less cost, and better experience for the surgeon.