Aim: To evaluate the effect of fractionated peribulbar anaesthesia and varying digital ocular compression time on intraocular pressure.
Methods: Forty non-glaucomatous patients aged 40 years and older planned for cataract surgery were randomly divided into 2 groups based on the duration for which the globe was compressed digitally following each injection. Patients with a history of glaucoma or those who had had previous ocular surgery were excluded. Group 1 underwent 1 minute of compression and group 2 underwent 2 minutes of compression. Local anaesthetic (2% lidocaine 5 mL, 0.5% bupivacaine 5 mL, and hyaluronidase 25 IU/mL) was injected into the inferotemporal and superomedial quadrants. Intraocular pressure was measured (3 readings with <5% SD) before peribulbar block, after inferotemporal injection, following digital compression, after superomedial injection, following digital compression again, and at 1-minute intervals without compression until the globe attained normotension.
Results: The mean (SD) intraocular pressure in group 1 was significantly elevated compared with the baseline mean intraocular pressure of 19.21 mm Hg (SD, 2.82 mm Hg) throughout the procedure (p < 0.0001). In group 2, the mean intraocular pressure was not significantly elevated from the baseline mean intraocular pressure of 19.13 mm Hg (SD, 3.27 mm Hg) following compression after each injection.
Conclusions: Intraocular pressure rises significantly following each 5 mL of local anaesthetic injected into the peribulbar space at both the inferotemporal and superomedial sites. Digital ocular compression given for 2 minutes after each injection makes the globe normotensive.