Peribulbar Anesthesia Can Damage Retinas of Patients With Glaucoma

Peribulbar anesthesia used for cataract surgery appears to have a detrimental ischemic effect on the retinal vasculature of patients with primary open-angle glaucoma (POAG), according to research published in Clinical Ophthalmology.

The study used optical coherence tomography angiography (OCT-A) images to assess the effect of the anesthesia on patients with glaucoma between August 2021 and February 2022.

All patients underwent cataract surgery using local peribulbar anesthesia (6 mL of peribulbar anesthetic injection of 4 mL lidocaine 2% containing 150 IU hyaluronidase and 2 mL bupivacaine 0.5%) and were scanned with OCT-A 10 minutes before and 10 minutes after anesthetic injection. OCT-A measurements included foveal deep (DCP), superficial (SCP) capillary plexuses density and total vessel density, foveal avascular zone (FAZ) diameter, optic disc total vessel density, and radial peripapillary capillary (RPC) network density. IOP was assessed before and 10 minutes after injection.

The study included 49 patients undergoing cataract surgery. Patients were divided into 2 groups, patients with no history of glaucoma (n=26; mean age, 58 years) and those with previously diagnosed POAG with controlled intraocular pressure (IOP; n=23; mean age, 56 years). The researchers observed no significant differences between the groups in pre and post-injection IOP (without POAG, 14 vs 15; P = .093; with POAG, 15 vs 17; P = .071, respectively).

The team found significantly greater median percent changes in the patients with POAG than those without POAG for post-injection DCP (-43% vs -2.5%; P <.001), DCP total density (-21% vs -0.9%; P <.001), foveal SCP vessel density (-62.6% vs -2.6%; P <.001), total vessel density (-16.2% vs -1.1%; P < .001); FAZ diameter (40.6% vs 2.5%; P <.001); optic disc total vessel density (-13.6% vs -1.1%; P <.001), and RPC network density (-13.1% vs -1.25%; P <.001).

“Peribulbar anesthesia harbors a deleterious ischemic effect on the retinal vascular tree of glaucoma patients, which could harmfully affect the vision and the visual field in those vulnerable patients,” according to the researchers.

The primary limitations were the relatively small sample size and the single-center setting of the study.

Reference

Awwad MA, Masoud M, Elhadad MA. Quantitative OCT angiography assessment of the effect of peribulbar anesthesia on retinal microvasculature in primary open-angle glaucoma patients undergoing cataract surgery. Clin Ophthalmol. Published online June 20, 2022. doi:10.2147/OPTH.S369969