Adding low dose rocuronium to local anesthetic mixture: Effect on quality of peribulbar blockade for vitreoretinal surgery

BackgroundThe purpose of this study was to assess the effect of adding low dose rocuronium to local anesthetic solution on the quality of peribulbar blockade for vitreoretinal (VR) surgery.Methods80 consecutive adult patients scheduled for VR surgery were enrolled in this double-blind randomized clinical trial. Patients were categorized randomly into 2 equal groups: group C (control group) received local anesthetic mixture (4 ml lidocaine 2%, 4 ml bupivacaine 0.5%, and hyaluronidase “30 U/ml”) plus 0.5 ml normal saline, and group S (study group) received the same local anesthetic mixture plus 5 mg (0.5 ml) rocuronium. Globe and lid akinesia were assessed 15 min after injection, and supplemental peribulbar blockade was done in case of inadequate analgesia and or akinesia. Intraoperatively, supplementary sub-Tenon infiltration was performed in case of inadequate analgesia and/or akinesia. Measurement data included rate of supplementation, analgesic efficacy, time to first sub-Tenon infiltration, and total anesthetic volume. Major complications, and patient’s and surgeon’s satisfaction were also recorded.ResultsThe adequacy of peribulbar blockade 15 min after injection was comparable in both groups. Rate of supplementary sub-Tenon infiltration was lower in the rocuronium group which is statistically significant (15 injections versus 53 injections in the control group). Time to first sub-Tenon infiltration was significantly prolonged in the rocuronium group (90.4 + 11.8 versus 60.2 + 9.2 in the control group). The total anesthetic volume injected was significantly lower in the rocuronium group (13.2 + 0.6 versus 20.6 + 0.8 in the control group). There were no major systemic or local complications in both groups. Patient’s and surgeon’s satisfaction was significantly higher in the rocuronium group.ConclusionAdding low dose rocuronium to local anesthetics prolongs duration of peribulbar anesthesia and offers an optimal surgical condition without serious adverse effects for patients undergoing VR surgery.