Background: Intraoperative retrobulbar bupivacaine injection provides effective analgesia after scleral buckling procedures performed under general anesthesia, but is associated with significant risks.
Methods: The safety and analgesic efficacy of an extraconal technique using a blunt cannula was evaluated. Forty patients undergoing scleral buckling procedures with general anesthesia were randomized to intraoperative extraconal bupivacaine injection (bupivacaine group. n = 21) or to no such treatment (control group, n = 19). General anesthetic and postoperative analgesia regimens were standardized. Analgesia requirements, pain, nausea, and sedation levels were graded at four intervals the first 24 hours after surgery. Chemosis was assessed 1 day after surgery, and ocular motility was assessed at 1 day, 1 week, and subsequent review.
Results: Maximum, 0 to 2-hour, and 4 to 6-hour pain levels were lower in the bupivacaine group than the control group (Wilcoxon rank sum, P < 0.005, < 0.005, < 0.01, respectively). Postoperative analgesia was required within the first 24 hours of surgery by all patients in the control group, but by only 12 of 21 patients (57%) in the bupivacaine group (Fisher's exact test, P = 0.001). Ptosis with minimal supraduction defect was noted at first postoperative examination in two patients who had undergone extraconal bupivacaine injection but resolved within 1 week. No other complication was encountered.
Conclusion: Intraoperative extraconal bupivacaine injection appears to be a safe and effective method for reducing pain and analgesia requirements after scleral buckling procedures performed under general anesthesia.