Perineural Methylene Blue Infusion in Lower Limb Amputation Surgery

Tanta University

Status: Enrolling

Conditions: Lower Limb Amputation; Methylene Blue; Perineural

Treatments: Drug: bupivacaine saline; Drug: Bupivacaine methylene blue

Study type: Interventional

Funder types: Other

Identifiers

NCT05830630

36264PR174/4/23

Details and patient eligibility

About

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

Full 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.

Enrollment: 72 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

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.

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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72 participants in 2 patient groups

Bupivacaine methylene blue group

Experimental group

Description:

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

Treatment:

Drug: Bupivacaine methylene blue

Bupivacaine saline group

Active Comparator group

Description:

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

Treatment:

Drug: bupivacaine saline