Antagonism of Endogenous Opioids: Use in Interpretation of Injections
Middle Tennessee Research Institute
Summary
This study will study pain relief after spine injections that are used to guide care. Some improvements in pain from a procedure might be from placebo effect rather than the physiological effect of the procedure. The study will use naloxone to reverse the effect of the body's internal placebo system after a spine injection, so the placebo effect and the injection effect can be measured separately. This process may improve the understanding of spine injections and their ability to guide pain care.
Description
Nerve blocks are commonly used in pain medicine to diagnose painful conditions and predict response to invasive procedures and surgeries. Placebo responses may cripple clinicians' ability to interpret responses to nerve blocks and guide patient care, when reported pain relief is due to placebo rather than the nerve block. Existing methods to assess placebo response in clinical practice are limited and indirect. The area that is most explored is in the diagnosis of pain from the facet joints of the spine and relies on an indirect signal from repeated diagnostic injections. Lumbar medial branc…
Eligibility
- Age range
- 18+ years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * Capable of understanding and providing consent in English and capable of complying with the outcome instruments used * ≥3 months low back pain with persistent limiting symptoms despite conventional treatment (physical therapy and oral medications) * Low back pain NRS ≥ 4/10 in intensity on 7-day average and at time of lumbar medial branch block Exclusion Criteria: * Daily use of opioid medications or recreational drugs, or if using opioids PRN, report of opioid use within the 3 days prior to participating in the protocol * Positive urine drug screen for opioid medicati…
Interventions
- DrugNormal saline infusion
After assessment of response to lumbar medial branch block, 8 ml normal saline will be infused through IV over several minutes. 10 minutes will pass, and response to lumbar medial branch block procedure will be re-assessed. After this step, naloxone infusion will occur (see next intervention)
- DrugNaloxone infusion
After infusion of normal saline and re-assessment of response to lumbar medial branch block procedure, 8 milligrams of naloxone will be infused over several minutes. Then after 10 minutes, response to lumbar medial branch block procedure will be re-reassessed for the final time.
Location
- VA Tennessee Valley Healthcare SystemNashville, Tennessee