Clinical trial NCT04865185: Effect of Topical Lidocaine on Warm and Cold Sensation in Healthy Individuals
Official title: Effect of Topical Lidocaine on Warm and Cold Sensation in Healthy Individuals - a Randomized Crossover Trial
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Neuropathy;Peripheral
Thermal Hypesthesia
Keywords: Paradoxical Heat Sensations
Thermal Grill Illusion
Lidocaine
Lead sponsor: University of Aarhus
Sponsor class: OTHER
First posted: 2021-04-29
Enrollment: 60
Sex: ALL
Minimum age (years): 18
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: DIAGNOSTIC

Brief summary: The purpose of the present study is to systematically test the occurrence of paradoxical and illusory responses to cold and warm stimuli in healthy volunteers with artificial sensory loss.

Detailed description: Efficient thermal sensation is important for adequate behavioral response to cold or warm stimuli and early signs of neuropathy can be changes in the thermal sensation.

Alterations in thermal perception can results in paradoxical heat sensation (a warm perception when the skin is cooled) or a peculiar/burning sensation when the skin is stiumlated with simultaneous warm and cold (a "thermal grill").

Clarifying the occurrence of these paradoxical and illusory sensations, may help understanding early signs of peripheral neuropathy as well as thermal sensory perception.

The investigators plan to conduct a study on thermal sensory perception using a model of sensory loss in healthy volunteers and systematically test the occurrence of paradoxical heat sensations and responses to the thermal grill.

Eligibility criteria: Inclusion Criteria:

* Healthy subjects
* Age between 18 and 40 years
* Participant is able and willing to give informed consent.

Exclusion Criteria:

* Unable to understand and speak Danish
* Non-cooperative
* Chronic pain or acute pain the past week lasting more than 4 hours or pain on the day of investigation
* Pain medication within the last week
* Medication within the last week that can affect assessment
* Psychiatric or neurological disease and diseases that may affect the assessment
* Sensory disturbances
* History or symptoms of significant diseases (e.g. psychiatric or neurological disease, diseases that may affect the assessment, sensory disturbances, cancer, diabetes mellitus, liver diseases, kidney diseases, cardiovascular diseases)
* Pregnancy or lactation
* Jetlag or sleep deprivation
* Alcohol or drug abuse
* Consumption of cannabis the last 4 weeks and consumption of alcohol in the last 48 hours
* Any abnormality of the skin or of vascular origin at application site
* History of hypersensitivity to lidocaine, other amide-type anesthetics, or other contents of the lidocaine or vehicle

Primary outcomes:
measure: Paradoxical heat sensation (PHS)
timeFrame: 45 minutes
Secondary outcomes:
measure: Thermal Grill (TG)
timeFrame: 75 minutes
measure: Quality of the Thermal Grill (TG)
timeFrame: 75 minutes
measure: Pain intensity of the Thermal Grill (TG)
timeFrame: 90 minutes
measure: Intensity of unpleasantness of the Thermal Grill (TG)
timeFrame: 95 minutes
measure: Intensity of cold of the Thermal Grill (TG)
timeFrame: 95 minutes
measure: Intensity of warm of the Thermal Grill (TG)
timeFrame: 95 minutes
measure: Paradoxical heat sensation (PHS)
timeFrame: 30 minutes before drug application
measure: Thermal Grill (TG)
timeFrame: 20 minutes before drug application
Other outcomes:
measure: Thermal thresholds
timeFrame: 45 minutes
measure: Paradoxical heat sensation (PHS) using a modified protocol
timeFrame: 100 minutes
measure: Mechanical thresholds
timeFrame: 45 minutes
Locations:
city: Aarhus N
country: Denmark
facility: Danish Pain Research Center, Aarhus University, Aarhus University Hospital
Study officials:
affiliation: Danish Pain Research Center, Aarhus University
name: Ellen L Schaldemose, MD
role: PRINCIPAL_INVESTIGATOR
References: