Coyne, P.J., Wan, W., Dodson, P., Swainey, C., & Smith, T.J. (2013). A trial of Scrambler therapy in the treatment of cancer pain syndromes and chronic chemotherapy-induced peripheral neuropathy. Journal of Pain and Palliative Care Pharmacotherapy, 27, 359–364.

To evaluate the effectiveness of Scrambler therapy on cancer pain, chemotherapy-induced peripheral neuropathy, neuropathic pain, and quality of life

Scrambler therapy is cutaneous electrostimulation that blocks the effect of pain information on the cutaneous nerves. In this study, all participants received the intervention to the affected area for 45 minutes daily for 10 consecutive days (Monday–Friday). Pain was measured before and after each intervention session.

• N = 39  
• MEAN AGE = 56.5 years
• MALES: 41%, FEMALES: 59%
• KEY DISEASE CHARACTERISTICS: The majority of the study participants had chemotherapy-induced peripheral neuropathy (n = 33), followed by post-mastectomy pain (n = 3), postherpetic neuralgia (n = 2), and radiation-related pain (n = 1).
• OTHER KEY SAMPLE CHARACTERISTICS: Participants had to have pain or symptoms of peripheral neuropathy for longer than one month with an average daily pain rating of greater than 5 out of 10, or numbness that bothered the participant at least “a little bit.” Additionally, participants had to be adults with a life expectancy of longer than three months and an Eastern Cooperative Oncology Group performance status score of 0–2.

• Setting was not described.

• PHASE OF CARE: Multiple phases of care
• APPLICATIONS: Palliative care

• A repeated measures design with no control group was used to evaluate the intervention.

• Numerical Rating Scale (0–10) for pain
• Brief Pain Inventory (questions 2–5 and 9)
• Eastern Cooperative Oncology Group Chemotherapy-Induced Peripheral Neuropathy 20 scale
• All measurements were performed pre- and post-intervention.
• Comparisons were made between baseline day 1 and days 14, 30, 60, and 90.

Improvement in pain was found at all secondary endpoints (days 14, 30, 60, 90), with a statistically significant difference in pain between baseline and day 30 (p = 0.0049) and change over time (p = 0.0002). Sensory and motor components of the chemotherapy-induced peripheral neuropathy scale also were found to improve with statistically significant sensory improvement between baseline and day 30 (adjusted p = 0.0007) and change over time (p < 0.0001). For the motor component, significant findings included improvement between baseline and days 14, 30, and 60 (adjusted p = 0.0143, 0.1035, 0.0094, respectively) and change over time (p = 0.0019). Improvements in all components of the Brief Pain Inventory were found (i.e., “interference with normal life,” which were maintained for mood, sleep, relationships, etc). Pain interference with walking was improved significantly between baseline and day 30 (p = 0.0003). Use of opioids did not change.

Scrambler therapy improved acute and chronic pain among patients with cancer. Additionally, it had a lasting effect three months post-treatment. Quality of life also was improved with this pain treatment. Further study is needed to determine generalizability of these findings to other patients with cancer.

• Small sample (less than 100)
• Risk of bias (no control group)
• Risk of bias (no blinding)
• Risk of bias (no random assignment)
• Risk of bias (no appropriate attentional control condition)
• Unintended interventions or applicable interventions not described that would influence results
• Findings not generalizable
• Intervention expensive, impractical, or training needs
• Other limitations/explanation: What opioids and dose the participants were taking during the study, who delivered the intervention, and the expense of the intervention or training needs were unclear. Additionally, findings are not generalizable to other patients with cancer because of the lack of a control group or attentional control condition and the small, heterogeneous sample.
• Questionable protocol fidelity

Scrambler therapy appears to be a promising intervention for cancer-related pain and has no adverse effects. Because who delivers this treatment and its expense are unclear from this article, the implications to nursing are unclear. However, nurses knowing about this treatment is important because it may become a common method for treating cancer-related pain in the future.