Combined Peripheral (BreEStim) and Central Electrical Stimulation (tDCS) for Neuropathic Pain Management - Spinal Cord Injury

Not Applicable

Completed

Conditions: Pain Management

Interventions: Device: BreEStim
Device: tDCS
Device: tDCS sham

Registration Number: NCT03302793

Lead Sponsor: The University of Texas Health Science Center, Houston

Brief Summary: This study looks at the effect of combined breathing-controlled electrical stimulation (BreEStim) and transcranial direct current stimulation (tDCS) on neuropathic pain after spinal cord injury, amputation, or brain injury. The hypothesis is that a single session of combined BreEStim and tDCS will produce an additive analgesic effect. This record covers the study in a population of spinal cord injury patients. Note that this study will also enroll healthy volunteers, brain injury patients, and amputation patients and that this study as applied to these other populations will be covered in separate ClinicalTrials.gov records.

Detailed Description: Not available

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 12

Inclusion Criteria

between 18 and 75 years
male and female subjects
has neuropathic pain after traumatic spinal cord injury
has chronic pain, >3 months
is stable on oral pain medications at least two weeks. (patients are allowed to continue their pain medications, i.e., no change in pain medications.)

Exclusion Criteria

currently adjusting oral pain medications for their neuropathic pain
have pain, but not neuropathic (e.g., from inflammation at the incision wound of the residual limb or neuroma)
have a pacemaker, or other metal and/or implanted devices
have amputation in their arm(s)
have spinal cord injury (SCI) involving impairment of arms
have cognitive impairment from brain injury or are not able to follow commands, or to give consent
have asthma or other pulmonary disease
are not medically stable
have preexisting psychiatric disorders
alcohol or drug abuse
have a history of seizures/Epilepsy, or taking benzodiazepines, anticonvulsants, and antidepressants.
Mini-mental state examination (MMSE), a brief 30-point questionnaire test that is commonly used in the literature, will be used to screen for cognitive impairment. A brain injury patient with a score of 24 or lower on MMSE will be excluded.

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Combined BreEStim and tDCS, then BreEStim and tDCS sham	tDCS sham	BreEStim is voluntary breathing controlled electrical stimulation. tDCS is transcranial direct current stimulation.
BreEStim and tDCS sham, then combined BreEStim and tDCS	tDCS sham	BreEStim is voluntary breathing controlled electrical stimulation.
BreEStim and tDCS sham, then combined BreEStim and tDCS	BreEStim	BreEStim is voluntary breathing controlled electrical stimulation.
BreEStim and tDCS sham, then combined BreEStim and tDCS	tDCS	BreEStim is voluntary breathing controlled electrical stimulation.
Combined BreEStim and tDCS, then BreEStim and tDCS sham	tDCS	BreEStim is voluntary breathing controlled electrical stimulation. tDCS is transcranial direct current stimulation.
Combined BreEStim and tDCS, then BreEStim and tDCS sham	BreEStim	BreEStim is voluntary breathing controlled electrical stimulation. tDCS is transcranial direct current stimulation.

Primary Outcome Measures

Name	Time	Method
Pain as Assessed by Visual Analogue Scale (VAS)	baseline, 10 minutes after tDCS, 10 minutes after BreEstim	A Visual Analogue Scale (VAS) is a measurement instrument that tries to measure a characteristic or attitude that is believed to range across a continuum of values and cannot easily be directly measured. It is often used in epidemiologic and clinical research to measure the intensity or frequency of various symptoms. To allow a continuous assessment of pain, VAS uses a 10 cm line labelled at '0' with 'no pain' and '10' with 'worst pain'. The line is marked at a point corresponding to the assessment of the pain.

Secondary Outcome Measures

Name	Time	Method
Electrical Pain Threshold	baseline, 10 minutes after tDCS, 10 minutes after BreEstim	Trimmed surface electrodes (1 inch by 1 inch) were used to examine electrical pain thresholds upon application of electrical stimulation (electrical stimulator 7SA, Digitimer). To measure electrical pain threshold, a pair of electrodes was placed next to each other centered on the thenar eminence (which is a group of muscles on the palm of the human hand at the base of the thumb); the intensity of electrical stimulation was started from the sensation threshold level (determined in outcome measure 3) and increased in steps of 1 mA; and subjects were instructed to close their eyes and to say ''yes'' when they first felt electrical stimulation painful. The electrical pain threshold is the mA level at which a participant first felt electrical stimulation painful. To improve consistency among subjects, they were advised that the pain threshold level was equivalent to 1 on the 0-10 VAS scale. Three repetitions were made and the average was used as the electrical pain threshold.
Electrical Sensation Threshold	baseline, 10 minutes after tDCS, 10 minutes after BreEstim	Trimmed surface electrodes (1 inch by 1 inch) were used to examine electrical sensation threshold upon application of electrical stimulation (electrical stimulator 7SA, Digitimer). To measure electrical sensation threshold, a pair of electrodes was placed next to each other centered on the thenar eminence (which is a group of muscles on the palm of the human hand at the base of the thumb); the intensity of electrical stimulation was started from zero and gradually increased in steps of 0.1 mA; and subjects were instructed to close their eyes and to say ''yes'' when they explicitly felt electrical stimulation. The electrical sensation threshold is the mA level at which a participant explicitly felt electrical stimulation. Three repetitions were made and the average was used as the electrical sensation threshold.