Precautions & Contraindications

Now that you know what NMES is and the recommended parameters for its use, let’s talk about why we may not want to use NMES as a treatment modality. The list of contraindications and precautions (see Table below) for the use of NMES is extensive and covers a range of conditions, all of which could apply to any child presenting at your clinic.

Table 3: Contraindications and Precautions

Pacemakers/Inbuilt simulators

Peripheral Vascular Disease

Hypertension/Hypotension

Areas of excess adipose tissue

Neoplastic Tissue

Areas of Active tissue infection

Exacerbation of Existing Conditions

Sensory loss

Unable to communicate or co-operate

Unable to understand or provide feedback

NMES is contraindicated in patients with pacemakers and other inbuilt stimulators because there is a risk that the electrical stimulation coming from the NMES treatment could cause overstimulation of the heart (or other organ) or cause the pacemaker to switch off. This becomes very dangerous if the patient requires constant stimulation from the pacemaker. However, depending on how the pacemaker is utilised, this can be overridden with the consent of the relevant physician (Robertson, Chipchase, Laasko, Whelan, McKenna, 2001). 

NMES can cause movement of a thrombus in patients with peripheral vascular disease and can affect the autonomic responses of people with hyper- or hypo-tension (Kitchen & Bazin, 1998, Roberston et al, 2001). Obese subjects may require high levels of stimulation in order for the treatment to reach the target muscle. This high level of stimulus can cause autonomic changes (Kitchen & Bazin, 1998).

When neoplastic tissue or areas of active tissue infection are involved, there is the potential for NMES to cause dissemination of the neoplastic/infected tissue. This is considered a precaution only as when the neoplastic/infected tissue is in an area well outside the treatment area, electrical stimulation can be used safely (Kitchen & Bazin, 1998, Robertson et al, 2001). Electrotherapy can also be used safely in palliative care.

NMES and electrotherapy can cause exacerbation of existing conditions such as skin conditions, areas of increased fluid tension, areas recently treated with radiotherapy, haemorrhagic conditions and severe organ states (Robertson et al, 2001).

Sensory loss is a very important precaution (Robertson et al, 2001). The patient must be able distinguish hot from cold or sharp from blunt to know if the treatment is going well or causing them harm. However, if the patient does have some sensory loss, treatment can still be administered as long as the treatment area includes an area of normal sensation.

Even though the cohort we are talking about treating are children with CP or ABI’s and it would be unlikely that a child with these conditions would also have one of the contraindicated conditions above, it is possible. Therefore we must always take a detailed history to ensure NMES is a safe option for our clients, even more so because they are children.

The interesting thing about the use of NMES in children with CP is that it is contraindicated in patients who are unable to understand the nature of the intervention or provide feedback about the treatment (Kitchen & Bazin, 1998, Watson, 2008). Patients unable to comprehend instructions, cooperate or communicate are contraindicated for general electrotherapy treatment (Robertson et al, 2001, Watson, 2008). Both of these guidelines generally preclude children from benefiting from NMES and all other electrotherapy modalities. Studies have shown that with careful consideration, patience and the support of proactive carers, NMES can be used safely and effectively in children as young as 16 months old (Carmick, 1993, Carmick, 1997). NMES can be safely used on children with CP and other motor deficits caused by neurological disorders. It has been shown that if the child is given some level of control over the device, they are more cooperative and the treatment can then progress as normal (Carmick, 1993, Carmick, 1997).

Once we have ascertained that it is safe to use NMES on our client, we need to consider electrode placement. Electrodes should never be placed trans-abdominally or trans-thoracicly as well as over the carotid sinus and the phrenic nerve (Kitchen & Bazin, 1998, Robertson et al, 2001, Watson, 2008). This is because the electrical current used for the therapy has the potential to interfere with the normal rhythm of the heart, damage the viscera, and affect nerve conduction and the baroreceptors found in the carotid sinus. Electrodes should not be placed too far apart and they should be an appropriate size so the target muscle is isolated and there is minimal outflow to surrounding muscles.

By Sara Gibbs

References:

Kitchen, S., Bazin, S. (1998). Clayton's Electrotherapy (10 ed.). London, England: WB Saunders Company Ltd.

Watson, T. (2008). Physiotherapy Essentials : Electrotherapy : evidence-based practice (12 ed.). St Louis, MO, USA: Churchill Livingstone.

Carmick, J. (1997). Guidelines for the Clinical Application of Neuromuscular Electrical Stimulation (NMES) for Children with Cerebral Palsy. Pediatric Physical Therapy 128-136

Carmick, J. (1993). Clinical Use of Neuromuscular Electrical Stimulation for Children with Cerebral Palsy, Part 1: Lower Extremity. Phys Ther 73 505-513

Roberston, V. J., Chipchase, L. S., Laasko, E. L., Whelan, K. M., McKenna, L. J. (2001) Guidelines for the Clinical Use of Electrophysical Agents. Australian Physiotherapy Association