TENS, which stands for transcutaneous electrical nerve stimulation, is frequently performed by physical therapists to decrease pain, and may be used at home as well. During TENS, a current is run through electrodes placed on the skin, creating a pins-and-needles sensation. While it can be a useful pain treatment, several groups of patients should not use TENS.
Decreased Sensation
The intensity of impulses is controlled by an adjustable TENS unit. Some people can tolerate only a low intensity while others prefer the device to be turned up quite high. A person without good sensation, however, may not feel discomfort regardless of the intensity of the TENS. Because of this, such patients are at a higher risk for burns from a high-intensity TENS session. Additionally, some people’s skin may become irritated by the pulses or the electrodes themselves. These small burns and/or irritation may not be noticeable until the electrodes are removed, and the damage has been done.
Certain Medical Conditions
There are a few medical conditions for which TENS is either contraindicated or used only with caution under careful supervision. These include cancer, pregnancy, epilepsy and people with heart pacers. Some physicians approve of TENS for patients with cancer or pregnant women, provided it is away from the tumor site or the uterus; however, many therapists are still cautious in these cases, because of the potential for cancer cells to spread or for a woman to go into premature labor. People with epilepsy should not have TENS treatment near their head or neck as there is a risk of seizure. Finally, TENS is not recommended at all for anyone with a heart pacer such as a pacemaker or a defibrillator, as it can interfere with the device.
Wounds or Irritated Skin
In general, it is not a good idea to place a sticky electrode over open or irritated skin. TENS can also further irritate compromised skin, potentially making a wound or skin condition worse. TENS can be applied further away from the wound site, provided the skin in that area is intact.
Certain Body Tissues
TENS should be applied to skin over muscle tissue only. It should not be used over or near the testicles, breast tissue, or facial structures. Additionally, TENS applied to the neck can cause problems with arteries close to the skin’s surface, such as the carotid.
Cognitive Impairments
TENS should be used only on people who can relate what they are feeling. If the unit's settings cause discomfort or irritation, the patient must be able to notify the therapist immediately. Like those with impaired sensation, a cognitively impaired individual is at a higher risk for irritation and burns, as they may not be noticed by the therapist until the device is removed. Additionally, when using TENS with a person who speaks a different language, an interpreter should be present to avoid any potential complications.
References
- Evidence-Based Guide to Therapeutic Physical Agents; Belanger, Alain-Yvan; 2003
- Guide to Physical Therapist Practice; American Physical Therapy Association, 2nd Ed.; 2001
