Biodegradable poly([D,L]-lactide-co-glycolide) nanofibers for the sustainable delivery of lidocaine into the epidural space after laminectomy

Aim: We developed biodegradable, lidocaine-embedded poly([D,L]-lactide-co- glycolide) nanofibers for epidural analgesia to reduce the severe pain in rats after laminectomies. Materials & methods: Nanofibers were prepared by an electrospinning process and were introduced into the epidural space of rats after laminectomy. The lidocaine concentration, postoperative bodyweight change and amount of food/water intake were monitored to evaluate the analgesic effectiveness of the drug-eluting nanofibers. Results: It was demonstrated that the nanofibers provided a sustained release of lidocaine for more than 2 weeks, and the local pharmaceutical concentration was much higher than the concentration in plasma. Rats that received laminectomies without nanofibers exhibited the greatest bodyweight reduction. The food/water intake and activity performance were significantly higher in rats receiving laminectomies with nanofibers than in rats without nanofibers. Conclusion: The results of this study suggest that the lidocaine-loaded nanofibers can provide an easy, practical and safe means of achieving effective postlaminectomy analgesia. Original submitted 23 April 2012; Revised submitted 25 October 2012; Published online 26 June 201.