Perineural Methylene Blue Infusion in Lower Limb Amputation Surgery

This prospective randomized controlled study will be conducted to evaluate the analgesic effect of continuous perineural infusion of methylene blue with bupivacaine on acute postoperative pain and to evaluate its preventive role against chronic phantom pain in patients undergoing lower limb amputation surgery

Inclusion Criteria: * Patients of both genders, suffering from vascular insufficiency of one or both lower limbs and scheduled for above or below knee amputation under general anesthesia. Exclusion Criteria: * Patients with a history of allergy to local anesthetics. * Patients with allergy to methylene blue. * Anticoagulant use or coagulopathy.