The Role of Peripheral Afferents in Modulating Post-stroke Central Pain

Launched by INSTITUT NATIONAL DE LA SANTÉ ET DE LA RECHERCHE MÉDICALE, FRANCE · Jun 5, 2024

Keywords

ClinConnect Summary

This clinical trial is investigating a new approach to help manage pain that can occur after a stroke, known as central post-stroke pain (CPP). This type of pain can be very challenging to treat with standard pain medications. Researchers want to see if two special nerve blocks, given 14 days apart, can help relieve this pain. Participants will receive either a local anesthetic called lidocaine, another called levobupivacaine, or a placebo (a harmless saline solution) to compare their effectiveness.

To be eligible for this trial, participants need to be at least 18 years old and have experienced chronic pain in their arms or legs for at least six months after having a stroke. They should have pain that is strong enough (rated at least a 4 out of 10) and have been on stable pain medication for two weeks prior to joining the study. The trial is currently recruiting participants, and those who take part can expect to receive either one of the treatments or the placebo while being monitored for any changes in their pain. It's important to note that some individuals, such as those with certain medical conditions or who are pregnant, may not be able to participate.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • 1. Patients aged 18 years and over with no maximum age (blocks are generally very well tolerated in the very elderly)
• • 2. Pain in the upper or lower limb distal enough to be completely covered by a peripheral nerve block
• • 3. Chronic pain for at least 6 months
• • 4. Ischaemic or haemorrhagic stroke for at least 6 months documented clinically and by appropriate imaging (MRI)
• • 5. Post-stroke central neuropathic pain defined as pain occurring in the aftermath of stroke meeting the criteria for probable or defined neuropathic pain according to the NeuPSIG algorithm and with a DN4 screening questionnaire score of at least 4 out of 10.
• • 6. Spontaneous pain intensity greater than or equal to 4 out of 10 on an 11-point numerical scale (EN) at inclusion and randomisation (i.e. just before each block)
• • 7. Patients affiliated to a social security scheme or beneficiaries of such a scheme
• • 8. Stable oral analgesic pharmacological treatment for at least 2 weeks prior to inclusion
• • 9. Acceptance and signing of the informed consent
• Exclusion Criteria:
• • 1. Inability or unwillingness to sign an informed consent
• • 2. Person subject to a legal protection measure (safeguard of justice, curatorship, guardianship)
• • 3. Patients with ongoing psychiatric pathology (major depression, psychosis) or cognitive disorders that prevent a good understanding of the protocol and questionnaires
• • 4. Pain that is too widespread in one hemicycle or limb and cannot be adequately covered by blocks
• • 5. Ongoing drug or substance abuse
• • 6. Language (aphasia) or comprehension disorders, illiteracy
• • 7. Moderate to severe renal or hepatic impairment
• • 8. Contraindication to local anaesthetics for use in perineural blocks (infection or acute inflammation in the injection area, known allergy).
• • 9. Pregnancy or breastfeeding
• • 10. Known hypersensitivity to lidocaine, levobupivacaine, amide-linked local anaesthetics or to any of the excipients contained in the specialities used in the study.
• • 11. Patients with recurrent porphyria or severe hypotension contraindicating treatment with lidocaine and/or levobupivacaine
• • 12. Current treatment with antiarrhythmic drugs causing torsades de pointes (amiodarone, disopyramide, quinidinics, sotalol...) or with antiarrhythmic drugs with local anaesthetic activity (mexiletine or class III antiarrhythmic drugs) and cannot be discontinued.
• • 13. Too little pain at the time of the blocks (\< 4 out of 10)
• • 14. Need to modify analgesic pharmacological treatment at the beginning or during the study