Breathing Controlled Electrical Stimulation

Author Year


PEDro Score

Research Design

Total Sample Size

Methods Outcome
Karri et al. 2018





Population: SCI+NP (n=10): Mean age=48.2 yr; Gender: males=10, females=0; Time since injury=13.3; Level of injury: C=7, T=0, L=3; Severity of injury: AIS A=2, B=1, C=4, D=3.SCI-NP (n=11): Mean age=38.6 yr; Gender: males=8, females=3; Time since injury=11.4 yr; Level of injury= C=4, T=7, L=0; Severity of injury: AIS A=3, B=2, C=5, D=1; Type of pain=neuropathic.

Intervention: SCI+NP patients received a breathing-controlled electrical stimulation (BreEStim) or a fake BreEStim randomly on separate days with at least a 3 day break between, both SCI-NP and SCI+NP participants had their visual analog scale pain scores and heart rate variability taken for comparison. Note that only the SCI+NP group had the BreEStim (active and null).

Outcome Measures: VAS scores and HRV.

1.     Significant difference in VAS scores across time for the active treatment (p<0.01) but not for the null treatment group (p>0.01).

2.     At baseline both the HRV time domain (p=0.01) and the HRV frequency domain (p<0.05) were significantly lower in the SCI+NP group than in the SCI-NP group.

3.     Significant interaction between effects of time and treatment and HRV for both time parameters (p=0.04).

4.     Parasympathetic tone profoundly increased across time only for the active intervention (p<0.05).

5.     Significant increase across time with active treatment for both time parameters (p=0.02) but no differences for the null treatment (p>0.05).

6.     Frequency parameters showed o significant differences across time for the null or active treatments (p>0.05).

Li et al. 2018


RCT Crossover



Population: Mean age=43.4±11.7 yr; Gender: males=7, females=5; Time since injury=15.5±12.3 yr; Level of injury: C=10, T=2, L=0; Severity of injury: all incomplete; Type of pain=neuropathic.

Intervention: Participants completed both the real and sham transcranial direct cranial stimulation (tDCS) followed by active breathing-controlled electrical stimulation/conventional electrical stimulation (BreEStim and EStim respectively) and were randomized to which they would complete in the first session and three days later in the second session.

Outcome Measures: Visual analog scores (VAS) for pain and analgesic effects.

1.     10 of the 12 participants completed both conditions because of timing conflicts.

2.     Positive analgesic effects were seen in active tDCS, but only in 4 of 10 participants in the sham tDCS and in BreEStim all but one participant saw positive analgesic effects.

3.     No difference in active and sham tDCS seen at the group level.

4.     VAS decreased from 5.7-5.1 after active tDCS and from 6.0-5.4 after the sham tDCS.

5.     Significant decrease in VAS after BreEStim in the active and sham tDCS group (p<0.00001 for both).

6.     All 12 participants completed the active tDCS and BreEStim and a main effect of time was observed to be significant (p<0.00001).

7.     No significant change of VAS observed after active tDCS, but a significant change was seen after active BeEStim (p<0.05).

Li et al. 2016 (1)




Population: Mean age=48.5±12.3 yr; Gender: males=6, females=7; Time since injury=58.2±45.8 mo; Level of injury: C=7, T=4, L=2; Severity of injury: AIS A=2, B=6, C=1, D=4; Type of pain=neuropathic.

Intervention: In the first of two experiments in this study, each of the 13 participants received both breathing-controlled electrical stimulation (BreEStim) and conventional electrical stimulation (EStim) with at least 3 days between bouts and 120 electrical stimuli each.

Outcome Measures: Visual analog score (VAS) for pain and analgesic effects.

1.     VAS average scores decreased from 6.3-3.7 after BreEStim120 and from 5.2-4.4 after EStim120.

2.     Significant main effect of intervention (p<0.001) with no main effect if stim.

3.     Significant interaction between intervention and stim observed (p<0.001).

4.     Significantly greater reduction in VAS score after BreEStim120 than after EStim120 (p<0.001) and the duration of the analgesic effect was significantly longer after BreEStim120 compared to EStim120 (p=0.04).

5.     Significantly greater intensity of electrical current during EStim120 compared to BreEStim120 (p=0.0189).


Three studies examined the effectiveness of BreEstim on reducing pain post SCI. Karri et al. (2018) found BreEstim significantly reduced pain compared to sham treatment. Li and colleagues (2018) found participants receiving BreEStim demonstrated reduction in pain intensity regardless of receiving active or sham tDCS. In a pre-post trial, participants were provided both a BreEStim and a conventional eStim device. The study found that participants experienced a reduction in pain intensity when using the BreEStim compared to conventional stimulation.


There is Level 1b evidence (from one RCT: Karri et al. 2018) that breathing-controlled electrical stimulation may improve pain post SCI.

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