Duration of Peripheral Nerve Blocks in Opioid Tolerant Individuals - A Volunteer Blinded Matched … (NCT06488768) | Clinical Trial Compass
CompletedNot Applicable
Duration of Peripheral Nerve Blocks in Opioid Tolerant Individuals - A Volunteer Blinded Matched Case-control Study
Denmark40 participantsStarted 2024-06-17
Plain-language summary
Do peripheral nerve blocks work shorter if you are on opioids?
Background:
Peripheral nerve blocks effectively alleviate postoperative pain. Animal studies and human research indicate that opioid tolerance results in reduced effectiveness of local analgesics. This applies to both central nerve blockade and infiltration anaesthesia. The impact on peripheral nerve block in humans has not been evaluated. The aim of the study is to assess the onset time and duration of a radial nerve block in opioid tolerant individuals compared to opioid naive individuals. We hypothesise that peripheral nerve blocks cause shorter sensory and motor block in opioid-tolerant compared to opioid-naive counterparts.
Methods:
Twenty opioid-tolerant individuals will be matched by sex and age with opioid-naïve counterparts. Participants will undergo an ultrasound-guided radial nerve block. The onset time and duration of motor and sensory blockade will be tested and measured. The primary outcome is difference in duration of sensory nerve blockade between the two groups. The secondary outcomes include the onset time of sensory blockade, onset time of motor blockade, and difference in duration of motor nerve blockade.
Perspectives:
The data from this study will provide evidence for the duration of peripheral nerve block in opioid tolerant individuals and support if a specific postoperative protocol for opioid tolerant individuals is needed or it should be of special attention.
Who can participate
Age range
18 Years – 84 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria for opioid group
* Age \> 18 years old
* ASA 1-3
* Chronic pain, defined as persisting pain for more than three months
* Daily use of more than 60 mg of morphine equivalent in more than 7 days
* Legally competent and able to give informed consent
Inclusion criteria for the opioid naive control group
* Age \> 18 years old
* ASA 1-3
* No use of opioids within 30 days prior to participation
* Legally competent and able to give informed consent
Exclusion Criteria:
* Age \> 84 years old
* Volunteers who cannot cooperate with the study
* Volunteers who cannot understand or speak Danish
* Allergy to the lidocaine or the preservatives used in the study
* Alcohol or drug abuse other than opioids
* Peripheral neuropathy at the upper limb non-dominant arm
* Pathology or previous major surgery to the upper limb
* Active signs of infection in the cutaneous area of injection
* Pregnancy at the time of the trial
* Partial or complete 2nd or 3rd degree atrioventricular heart block without a pacemaker
* Severe liver disease
* Severe kidney disease and reduced kidney function (eGFR below 30 mL/min)
* Daily treatment with drugs that are structurally related to local analgesics or class IB antiarrhythmics, as the toxic effects are additive
* Daily treatment with class III antiarrhythmics e.g., amiodarone.
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
The difference in the duration of sensory block for a radial nerve block between opioid-tolerant and opioid-naive individuals.
Timeframe: Up to one hour after nerve block placement.