Performing nerve conduction studies and electromyography in children shares the same fundamental principles with electrodiagnostic studies performed in adults. The nerves and muscles available for testing are mostly the same, electrode placement is similar, and data interpretation relies on the same basic physiology. However, there are nevertheless important differences that should be emphasized. Without sedation, younger children as well as those with developmental delay or cognitive impairment will often have difficulty tolerating the comprehensive nerve conduction studies involving as many as a dozen different motor and sensory nerves as well as extensive needle examination of multiple extremities that is more typical of adult studies. Older children and adolescents are more likely to tolerate the scale of testing that is familiar to adult neurophysiologists.

Do the limitations of the extent of testing that are typically present in a non-sedated study imply that pediatric electromyography is merely an abbreviated form of adult electromyography, or that all pediatric studies should be performed under sedation? The answer to both questions is no. The practical constraints happen to be compatible with the types of questions that are asked in different age groups. Infants and toddlers, in whom the technical challenges are most dramatic, often present for evaluation of generalized neuromuscular disorders rather than focal lesions such as mononeuropathies. This may include motor neuron disease and generalized myopathies. To address such questions requires not so much the examination of a set list of nerves and muscles but an accurate assessment of enough representative nerves and muscles in enough extremities to yield a conclusion with an acceptable level of diagnostic certainty. On the other hand, older children and adolescents are more likely to present with focal complaints that necessitate assessment for mononeuropathies. Exceptions do occur, an example being the evaluation of Erb’s palsy in infants.

In a child, it is almost always possible to obtain an electrodiagnostic study without sedation that is complete enough to answer the specific question at hand. For such a study to be successfully performed, the neurophysiologist must be patient, adaptable, and experienced in working with children. The assistance of other personnel, such as neurophysiology fellows and technologists, can be invaluable, but care must be taken not to fill the room with too many staff, as the introduction of numerous new faces simultaneously in an unfamiliar environment may increase the risk of frightening the child. When available, a child life specialist who is experienced with guiding children through medical procedures can also help soothe and calm the child during the study. Parents should generally be permitted and encouraged to be present to support and comfort the child, unless the child is being examined under sedation or general anesthesia in a procedure room where family members are prohibited from staying.

Knowledge of technical considerations will also help minimize discomfort and maximize the tolerance of the child for the study. When performing nerve conduction studies, the desire to use the lowest current needed should be balanced against the desirability of delivering as few stimulations as possible. Sensory studies should generally be performed prior to motor studies since smaller stimulation intensity is required. Gradually increasing the stimulation intensity by 1–2 milliampere (mA) at a time will likely result in the delivery of more stimulations than needed. Conversely, a rapid increase in intensity has the potential to startle and alarm the child. A reasonable compromise is to raise the current by about 5 mA increments until a reproducible, maximal sensory nerve action potential (SNAP) amplitude is obtained. For sensory nerve conduction studies in particular, it should be remembered that currents above 20–30 mA are rarely needed to obtain a supramaximal sensory nerve action potential. Supramaximal motor responses sometimes require higher currents, but often not. Except when specifically indicated to help answer the specific electrophysiologic question, F responses are usually not helpful and are uncomfortable for children, and should be elicited selectively. H reflexes are often exceedingly painful for young children and should only be obtained in rare circumstances in this age group. For the needle examination, the smallest concentric bipolar electrode commercially available is 25 mm in length and 0.3 mm in diameter (30 gauge) with a 0.03 mm² recording area. This thin needle electrode should be used in almost all circumstances for children and adolescents, unless a specific muscle is too deep to be sampled accurately by this electrode.

An informal poll conducted in 2015 by the author among a group of ten expert pediatric neurophysiologists yielded the following information about practice habits around the world. Local analgesia was used always by two neurophysiologists and sometimes by six others. Conscious sedation was used always by one neurophysiologist and sometimes by four others. General anesthesia was used sometimes by two neurophysiologists. These results suggest that in experienced hands, electromyography may be performed successfully in the majority of children either without any anesthesia or with the use of local analgesia only. A prospective, large-scale survey of children and their parents after electromyography found that the level of pain reported was equivalent or less than that of venipuncture by the majority of families [1].

Local analgesia is favored by some neurophysiologists and may be a practical and helpful option for some children in certain settings. Topically applied creams are most commonly used, while infiltrative drugs are rarely used, especially as the latter may introduce artifact. A popular topical cream used for many procedures is the eutectic mixture of local anesthetics (more commonly known as EMLA), which consists of lidocaine 2.5% and prilocaine 2.5%. EMLA has been documented to reduce pain for venipuncture in infants [2] and children [3], vaccinations in infants [4] and children [5, 6], and other intramuscular injections in infants and children [7]. The disadvantage of using EMLA is the prolonged lag time before onset of analgesia, which may be as long as an hour, though some children will experience pain reduction earlier [8].

Another popular cream delivers amethocaine, now known as tetracaine, with the brand name Ametop, which is favored by some neurophysiologists due to a shorter time to onset of analgesia, typically 30 min [9, 10]. Several studies have suggested greater potency of amethocaine compared to EMLA in children [11–13], while another study indicated equivalent efficacy [14], and another suggested that EMLA was more efficacious than amethocaine [15]. However, amethocaine has been more expensive than EMLA, at least in some markets [9].

There are two challenges to the use of such topical creams in the setting of a pediatric electromyography laboratory. First, the cream must be applied in advance of the needle examination, ideally at least an hour ahead of time for EMLA and 30 min ahead of time for amethocaine/tetracaine. If the cream is applied before the nerve conduction studies are performed, that may provide sufficient or nearly sufficient time for onset of analgesia. The second challenge is that the neurophysiologist must guess which muscles are most likely to require needle examination. In some situations the choice of muscles is predictable, but not in others. It is worth noting that distraction techniques have been found to be as effective as EMLA cream for children receiving venipuncture in one study [16].