Assessment, Identification, and Documentation of Neuromuscular Disorders

By Jean McCaslin, RN, IgCN, Clinical Nurse Educator

Regardless of the area of specialty any nurse is employed, we all have learned the importance of the holistic approach to patient care. We regularly assess cardiac and respiratory function through monitoring vital signs. We are trained to ask about a history of things like diabetes and high cholesterol. We adjust and adapt medications and work in concert with medical physicians to address these common medical conditions, thus improving our knowledge level in these areas.

It is however somewhat rare to be well versed in neuromuscular disorder (NMD) care. For nurses who have worked in an emergency room or intensive care unit, most neurology experience is achieved through treating trauma or stroke patients. In this blog, symptoms specific to NMD conditions will be explored.

The term neuromuscular disorder is used when describing disorders that primarily affect the nerves that control voluntary muscle movement and transmit sensory information to the brain. Testing for these disorders is very complex, as their causes have many origins. Some disorders are inherited, while others are acquired; some are primary conditions, while others are secondary to another disease process, toxin, infection, dietary deficiency or treatment modality. Regardless of the origin, most predominantly NMDs are known to wreak havoc on muscle movement and sensory function, yet some conditions may also affect autonomic function.

Muscle Weakness; Motor Nerves

One of the most easily recognizable and common symptoms of NMD is weakness. Unlike symptoms associated with excessive exercise which cause muscle fatigue, weakness persists despite rest in most NMDs. Weakness in NMD is the loss of strength due to the lack of electrical innervation to produce the muscle contraction(s) and resulting voluntary movement. Depending on the location of a "sick nerve" and the afflicted muscle group(s), it can make even the simplest ADLs seem impossible. Getting dressed, rising from a chair, combing one's hair, walking or eating could be problematic.

Change in Sensation; Dysesthesia, Paresthesia

The ability of our brain to perceive sensory stimuli may be affected by NMD. Dysesthesia is a general term to describe abnormal sensations that are not painful (e.g., bugs crawling, electrical sensation, tingling, itchiness or numbness). Paresthesia is specific to painful sensations (e.g., pins and needles, prickling, burning). These impairments may occur due to the brain receiving impulses from nerves that have been damaged by a NMD process; the signals may be partial, scattered, or blocked entirely.

Muscle pain; Myalgia

In NMD, even the simplest physical tasks can lead to significant pain, otherwise known as myalgia. Patients describe this pain as cramping of the muscles or sometimes pain in the joints. This is because the muscles, tendons, ligaments, bones, muscle fascia and ligaments can be involved. Patients may experience spasms or cramping sensations along one or more entire muscle(s).

Muscle Twitching; Fasciculation

A muscle twitch or fasciculation is an involuntary muscle contraction that is short and repetitive. The most commonly afflicted muscle groups in NMD are those in the arms, legs, shoulders, neck, face, hips and tongue. These muscle twitches can last minutes or hours at a time. These jumps or twitches occur when abnormal nerves produce ineffective, partial, or poorly synchronized nerve impulses.

Muscle Wasting; Atrophy

Muscles depend on innervation (electrical stimulation) from the brain to complete the process of muscle contraction. In NMD, individual muscles or entire muscle groups lack normal full nerve function which leads to weakness and muscle wasting. As the NMDs progress, the muscles in the affected body part(s) become increasingly weak and smaller in size. Muscle size, particularly unevenness of size, may be an overt sign of a NMD process.

Double Vision; Diplopia

Eyesight is dependent on the proper function of the involuntary muscles of the eyes. If these muscles are weak or experience spasms, vision may be affected. When both eyes are not synchronized with each other, this too leads to diplopia.

Droopy Eyelids; Ptosis

Oculomotor nerves are responsible for the movements of the eyes and eyelids. Specifically, the levator muscle moves the eyelid. Certain NMDs affect the nerves innervating these muscles causing ptosis or droopy eyelids.

Difficulty Swallowing; Dysphagia

The cricopharyngeal muscle is key in the swallowing process. Both contraction and relaxation of this muscle are necessary. When this muscle is unable to relax, food cannot be moved along into the esophagus. In fact, any disruption to any of the remaining swallowing/throat/esophagus muscles can diminish the ability to eat normally and prevent aspiration of food into the lungs. In addition to Myasthenia Gravis, peripheral neuropathies, motor neuron diseases and myopathy all can cause dysphagia.

Loss of Balance; Gait Ataxia

Many factors can contribute to an unsteady gait. Leg strength, eyesight, the inner ear, and tactile sensation are all necessary. In NMDs a number of these factors may be inadequate. Lower extremity neuropathies often affect proprioception, or the ability to sense the foots position in relation to the rest of the body.

Breathing Problems; Dyspnea

The breathing process requires synchronization between multiple muscle groups including the diaphragm, intercostal muscles and the accessory muscles. Many NMDs can interfere with the proper sequences needed to breathe properly.

Changes in Autonomic Function

Myasthenia Gravis has been seen to cause autonomic dysfunction involving multiple organ systems; these include gastrointestinal, orthostatic, pupillomotor, vasomotor or sudomotor processes. This is due to latent parasympathetic responsiveness.

Infusion nurses often administer Intravenous Immune Globulin (IVIG) to treat autoimmune-related neuromuscular diseases. We often bear witness to the significant improvements experienced by our patients receiving IVIG. We also are present to evaluate the worsening or relapse of symptoms in our patients. These gains or loses should be recorded in the Patient Assessment section of the Nufactor Nursing Note.

A nurse need not be a neuromuscular specialist to perform a basic neurological assessment. Our roles as historians are well understood. We need only to expand upon this skill by asking more pointed questions based on what we know about NMDs and the tolls they potentially take. Documentation should include the presence of ptosis of the eyes, dysphagia, gait ataxia, weakness of certain muscle groups or dyspnea on exertion.

Nurses in the home often see individual patients on a more frequent basis than neuromuscular physicians do. Recognizing and reporting gains or losses in neurological function can improve outcomes for the patients we care for, as changes to dosing or to treatment modalities may result from astute nursing communication.