Perineural Methylene Blue Infusion in Lower Limb Amputation Surgery

Not Applicable

Recruiting

• Conditions: Perineural; Methylene Blue; Lower Limb Amputation
• Interventions: Drug: bupivacaine saline; Drug: Bupivacaine methylene blue

• Registration Number: NCT05830630
• Lead Sponsor: Tanta University

Brief Summary

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

Detailed Description

Post amputation pain remains an extremely challenging pain condition to treat, so the prevention of phantom pain is our goal to decrease its incidence.

Methylene blue, an inhibitor of nitric oxide synthase and guanylate cyclase, has been widely applied for a variety of pain-related diseases due to its characteristic abilities, such as the blocking of pain transmission, antioxidant, and anti-inflammatory effects. Methylene blue can maintain local anesthesia for approximately 20 days so it can be used as a nerve block to relieve pain, especially refractory neuropathic pain.

Study Timeline

• Study First Submitted: 2023-04-14
• Study First Submitted QC: 2023-04-14
• Study First Posted: 2023-04-26
• Study Start: 2023-05-01
• Status Verified: 2024-06
• Last Update Submitted: 2025-05-05
• Last Update Posted: 2025-05-06
• Primary Completion: 2026-08-01
• Study Completion: 2027-05-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 72

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.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Bupivacaine saline group	bupivacaine saline	Patients in this group will receive the following regimen through the perineural catheter: Bolus dose of 1 ml normal saline plus 19 ml bupivacaine 0.25% will be given intraoperatively before wound closure, and perineural infusion of bupivacaine 0.25% will be started in the recovery room at a rate of 2-5 ml/hour for 72 hours postoperatively
Bupivacaine methylene blue group	Bupivacaine methylene blue	Patients in this group will receive the following regimen through the perineural catheter: Bolus dose of 1 ml methylene blue 1% (10 mg) plus 19 ml bupivacaine 0.25% will be given intraoperatively before wound closure, and perineural infusion of methylene blue plus bupivacaine 0.25% (1 ml of methylene blue added to each 49 ml of bupivacaine 0.25%) will be started in the recovery room at a rate of 2-5 ml/hour for 72 hours postoperatively

Primary Outcome Measures

Name	Time	Method
Degree of postoperative pain	3 days after surgery	Degree of postoperative pain will be assessed using visual analogue scale which is a 10 cm scale ranging from (0 = no pain to 10 = worst possible pain)

Secondary Outcome Measures

Name	Time	Method
Incidence of phantom limb pain	9 months after surgery	Incidence of phantom limb pain at day 6 after surgery then at 1, 3, 6, 9 months after surgery

Trial Locations

Locations (1)

Tanta University; 🇪🇬 Tanta, Gharbiya, Egypt