Neuropathic Pain, Neuropathy;Peripheral, Painful Diabetic Neuropathy
Conditions
Brief summary
The purpose of the present study is to evaluate the role of peripheral afferent input for spontaneous pain in painful diabetic polyneuropathy
Detailed description
Both peripheral and central changes in the nervous system contribute to the development of painful diabetic neuropathy, but how these changes contribute to the pain generation remains yet to be fully understood. The purpose of this study is to evaluate if a peripheral regional nerve block relieves spontaneous pain in painful diabetic polyneuropathy.
Interventions
DIAGNOSTIC_TESTXylocaine 1%
Nerve block
DIAGNOSTIC_TESTNaCl 9mg/ml
Nerve block
Sponsors
University of Aarhus
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
DIAGNOSTIC
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Aged 18 years or older. * Probably diabetic neuropathy confirmed using the Toronto criteria in a conservative manner, i.e. three out of three symptoms/signs of neuropathy must be present (sensory neuropathy symptoms, distal reduced sensibility, reduced ankle reflexes) 7. * Definite or probable neuropathic pain for minimum the last 6 months * Mean pain intensity at \> 4 NRS the last week17. Since we expect a large effect of the block it is not necessary to discontinue pain medication.
Exclusion criteria
* Other causes of pain in the same area or other pain that cannot be distinguished from the neuropathic pain. * Unable to understand and speak Danish. * Non-cooperative. * Warfarin or other medication that contraindicate regional anesthesia. * Infection in the injection area. * Allergy to lidocaine. * Pregnancy or lactating (fertile women must to show negative pregnancy test or use anticonception). * Severe psychiatric disease e.g. severe depression during the last 6 months. * Alcohol or drug abuse.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Indication of pain relieved extremity | 30 minutes | Number of participants who indicated the leg with lidocaine as most pain relieved 30 minutes after block And number of participants who indicated the leg with saline as most pain relieved 30 minutes after block |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pain intensity | 90 minutes | Intensity of spontaneous pain (Numeric Rating Scale (NRS) 0-10, 0=no pain 10=worst pain imaginable) 30, 45, 60 and 90 minutes after block |
| Hyperalgesia and allodynia | 90 minutes | Intensity of hyperalgesia and allodynia from -5 to 5 (-5 = no sensation, 0=normal sensation, 5=extremely intense sensation) to brush, pinprick, cold and warm at baseline and if there is registered any signs of hyperexcitability at baseline then 35, 60 and 90 minutes after nerve block. |
| Pain relief | 45 minutes | Pain relief at 45 minutes after block assessed using a 6-point scale compared to pain intensity at baseline. (-1 = worse pain 0=no relief 1= little 2= moderate 3=good 4=complete) |
| Pain symptomps | 50 minutes | Intensity of neuropathic pain symptoms 50 minutes after nerve block Burning: NRS (0-10), 0=no burning 10=worst burning imaginable Squeezing: NRS (0-10), 0=no squeezing 10=worst squeezing imaginable Pressure: NRS (0-10), 0=no pressure 10=worst pressure imaginable Tingling: NRS (0-10), 0=no tingling 10=worst tingling imaginable |
| Distribution of evoked pain | 60 minutes | The distribution of any evoked pain to brush, pinprick, cold and warm before and 60 minutes after nerve block will be mapped using a filt pen and afterwards photographed. |
Countries
Denmark
Contacts
Primary ContactEllen L Schaldemose, MD
Outcome results
None listed