A New Two-Step Anesthesia for 23- or 25-Gauge Vitrectomy Surgery: A Prospective, Randomized Clinical Trial

To investigate the safety and efficacy of topical anesthesia combined with subconjunctival anesthesia (termed two-step anesthesia) for 23- or 25-gauge pars plana vitrectomy or other posterior segment surgery.

Patients (n = 90) requiring 23-/25-gauge vitrectomy or other posterior segment surgery were randomized into 3 groups. Group 1 received peribulbar anesthesia, group 2 received retrobulbar anesthesia and group 3 received two-step anesthesia. A 5-point visual analog pain scale (VAPS) was used to measure self-report of patient pain. Complications were recorded for subsequent analysis.

VAPS scores for overall intraoperative pain ranged from 0 to 3 (1.07 ± 1.07) in group 1, from 0 to 2 (0.69 ± 0.93) in group 2 and from 0 to 3 (1.06 ± 0.98) in group 3. Assessment of surgeon discomfort score ranged from 0 to 2 (0.31 ± 0.66) in group 1, from 0 to 3 (0.38 ± 0.82) in group 2 and from 0 to 2 (0.47 ± 0.62) in group 3. Both scores reveal no significant difference among the 3 groups. While there were no complications noted in group 1, there was an ocular perforation in group 2. Additionally, there were no complications in group 3 related to the anesthetic technique.

Results suggest that two-step anesthesia is a safe and effective anesthetic approach for selected patients undergoing 23- or 25-gauge pars plana vitrectomy or other posterior segment surgeries. It may offer a viable alternative to peribulbar anesthesia and retrobulbar anesthesia for carefully selected 23- or 25-gauge cannular-access ocular surgeries.