Evaluation of reduced volume of local Anesthetic solutions in retrobulbar block: a safe and effective alternative

Introduction: Retrobulbar anesthesia is widely used in ophthalmic surgeries due to its ability to provide effective analgesia and ocular immobility. However, standard local anesthetic solution (LAS) volumes are associated with orbital and systemic complications, especially in patients with comorbidities. This study evaluated the efficacy and safety of reduced AL volume (3 mL) for retrobulbar block. Methods: A retrospective and descriptive study was conducted with 37 patients undergoing phacoemulsification and pars plana vitrectomy. The block was performed using 1% lidocaine, 0.375% bupivacaine, and hyaluronidase (3 mL), with assessments of hemodynamic parameters, anesthetic efficacy, and complications. Results: The effective block rate was 91.9%, with hemodynamic stability evidenced by reduced heart rate (66.84 bpm to 64.27 bpm) and blood pressure (145/085 mmHg to 130/078 mmHg). No major complications were recorded. Block failures (8.1%) were associated with systemic hypertension and diabetes mellitus. Conclusion: Using 3 mL of LAfor retrobulbar block proved effective and safe, maintaining comparable results to standard volumes while reducing the risk of complications. Future studies should explore the inclusion of adjuvants and intraocular pressure monitoring to further optimize the technique.