A Non-invasive Intervention (BreEStim) for Management of Phantom Limb Pain (PLP) After Limb Amputation (Experiment 2)

Not Applicable

Completed

Brief Summary: The purpose of this study is to compare the effectiveness of innovative intervention of breathing controlled electrical stimulation (BreEStim) and conventional electrical stimulation (EStim) in management of neuropathic phantom limb pain in patients after limb amputation.

Recruitment & Eligibility

Inclusion Criteria

has phantom limb pain (PLP) after amputation of one limb, upper or lower limb;
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 PLP;
has pain, but not PLP (e.g., from inflammation at the incision wound of the residual limb);
has a pacemaker, or other metal and/or implanted devices;
has cognitive impairment from brain injury or are not able to follow commands, or to give consent;
has amputation in multiple limbs;
have asthma or other pulmonary diseases;
are not medically stable;
have preexisting psychiatric disorders;
alcohol or drug abuse;
have a history of seizures/Epilepsy, or taking benzodiazepines, anticonvulsants, and antidepressants.

Arm && Interventions

Group	Intervention	Description
BreEStim 120, then BreEStim 240	BreEStim 120	BreEStim is voluntary breathing controlled transcutaneous electrical nerve stimulation. 120 vs 240 BreEStim electrical stimuli will be compared to examine the impact of different stimuli "dose" on pain reduction in this experiment.
BreEStim 120, then BreEStim 240	BreEStim 240	BreEStim is voluntary breathing controlled transcutaneous electrical nerve stimulation. 120 vs 240 BreEStim electrical stimuli will be compared to examine the impact of different stimuli "dose" on pain reduction in this experiment.
BreEStim 240, then BreEStim 120	BreEStim 120	BreEStim is voluntary breathing controlled transcutaneous electrical nerve stimulation. 120 vs 240 BreEStim electrical stimuli will be compared to examine the impact of different stimuli "dose" on pain reduction in this experiment.
BreEStim 240, then BreEStim 120	BreEStim 240	BreEStim is voluntary breathing controlled transcutaneous electrical nerve stimulation. 120 vs 240 BreEStim electrical stimuli will be compared to examine the impact of different stimuli "dose" on pain reduction in this experiment.

Primary Outcome Measures

Name	Time	Method
Change in Pain Level as Measured by the Visual Analog Scale (VAS).	Baseline, 10 minutes after intervention	VAS Scores are recorded from 0 to 10 with 0 being "no pain" and 10 being "worst pain", a higher score indicating a higher level of pain. Change is reported as \[(VAS score at baseline) - (VAS Score 10 minutes after intervention)\] - a positive value indicates that the score (and pain level) decreased

Secondary Outcome Measures

Name	Time	Method
Change in Sensation Threshold on Amputated Limb Measured by Electrical Sensation Threshold (EST)	Baseline, 5 minutes after intervention	Electrical Sensation Threshold (EST) is the minimum electrical current intensity that a person can reliably perceive as a sensation on their skin. This threshold is self-reported by the subjects, and electrical intensity values are recorded when participants first detect the electrical stimulation. Change is reported as \[(EST at 5 minutes after intervention) - (EST at baseline)\] - a positive value indicates a decrease in sensation perception.
Change in Pain Threshold on Amputated Limb Measured by Electrical Pain Detection Threshold (EPT)	Baseline, 5 minutes after intervention	An Electrical Pain Threshold (EPT) refers to the minimum intensity of electrical stimulation required to produce a perceptible pain sensation on a person's skin, essentially measuring the point at which an electrical current becomes painful. The EPT is self-reported by subjects when they feel the electrical intensity begins to cause pain. Change is reported as \[(EPT at 5 minutes after intervention) - (EPT at baseline)\] - a positive value indicates an increase in pain threshold.