Postoperative pain control of subtenon bupivacaine injection in adult strabismus surgery: a double-masked randomized trial

Abstract

Background: Pain from intraoperative retraction of extraocular muscles is the main cause of ocular discomfort after strabismus surgery. Injection of the long-acting local anesthetics can reduce ocular pain after strabismus surgery under general anesthesia. Purpose: To evaluate the e cacy of subtenon bupivacaine injection on postoperative pain control Methods: A prospective double-masked randomized trial was conducted in 18 eyes of 9 patients (age range 20-67 years) who underwent binocular strabismus surgery under general anesthesia at Thammasat hospital. Both eyes of each patient were randomized to receive subtenon injection with 0.5% bupivacaine 0.1 ml in one eye and sterile saline injection in the fellow eye at the end of surgery. Primary outcome measures were visual rating pain scores at 30 minutes, 1 hour, 4 hours and 6 hours postoperatively. Secondary outcome measures were adverse e ects of bupivacaine injection. ral acetaminophen was added as per patient pain requirement. The doses of this adjunctive analgesia were recorded. Results: Average pain score between study group vs control group was 1.33 vs 2.66, 1.44 vs 2.77, 1 vs 1.66 and 0.3 vs 1.3 in the rst 30 minutes, 1 hour, 4 hours and 6 hours, respectively. Pain scores at the rst 6 hours postoperatively were signi cantly lower in the study group (P 0.001). Discussion: Adjunctive subtenon bupivacaine injection had e ects at the rst 6 hours postoperatively in adults undergoing strabismus surgery with general anesthesia technique. Conclusion: Subtenon injection of bupivacaine may reduce postoperative pain score in adult strabismus surgery.

Development and Optimization of Chitosan-Hydroxypropyl Methylcellulose In Situ Gelling Systems for Ophthalmic Delivery of Bupivacaine Hydrochloride

“…In the first phase, there is a rapid release, known in the literature as the "burst effect", followed by a prolonged release for 6 h. This two-stage process corresponds to a rapid initial onset of local anesthetic action of bupivacaine hydrochloride in ocular surgery, followed by a gradual analgesic action maintained for a longer period of time, a beneficial aspect in postoperative pain management [46,47].…”