Learning Objectives
By the end of this section, you will be able to:
- Discuss the pathophysiology, risk factors, and clinical manifestations for polyneuropathy
- Describe the diagnostics and laboratory values of polyneuropathy
- Apply nursing concepts and plan associated nursing care for the patient with polyneuropathy
- Evaluate the efficacy of nursing care for the patient with polyneuropathy
- Describe the medical therapies that apply to the care of polyneuropathy
A peripheral nerve disorder called polyneuropathy occurs when multiple peripheral nerves all over the body are damaged and malfunction simultaneously. As noted previously, the peripheral nervous system is the division of the nervous system containing the nerves that travel from the brain and spinal cord to carry signals to the rest of the body. The peripheral nervous system enables somatic functions and autonomic functions. A somatic function is a conscious movement that an individual controls, such as moving the arms and legs. An autonomic function is an automatic movement, such as heart beating, that individuals do not control.
Polyneuropathy can disrupt nerve communication in several ways. For example, lost nerve signals should occur but do not, whereas other nerve signals occur at inappropriate times. And, still other signals occur when they should but deliver an error message. Although the symptoms of polyneuropathy can be severe, even disabling some patients, the condition is rarely life-threatening.
Pathophysiology
Polyneuropathy may be caused by health conditions, such as infections, tumors, bone marrow disorders, kidney failure, cancer, autoimmune diseases such as lupus or rheumatoid arthritis, and other diseases such as hypothyroidism or liver disease. Other causes include alcoholism, vitamin deficiencies, exposure to toxins, and injuries that damage the peripheral nerves. Some medications, particularly those used in chemotherapy, may cause polyneuropathy. Finally, the most common cause is diabetes, with more than 50 percent of people who have diabetes also developing a type of neuropathy, including polyneuropathy (Mayo Clinic, 2023g).
Clinical Manifestations
Polyneuropathy develops slowly in some patients, becoming a chronic case, whereas other patients have an acute case, with a sudden appearance of polyneuropathy. The symptoms vary depending on which type of nerves are damaged. Polyneuropathy can affect the following nerves:
- A motor nerve controls muscles that require voluntary control, such as those used to talk and walk. Symptoms include muscle weakness and/or shrinking, cramps, inability to move body parts under voluntary control such as the hands and feet, and fasciculation, which is an uncontrolled twitching in the muscles.
- A sensory nerve transmits messages about pain, temperature, feelings, and other information gathered by the senses. Symptoms include loss of reflexes; lack of coordination and/or balance; numbness, particularly in the hands and feet; feelings of sensitivity and pain from things that should not hurt, such as clothing; feeling like pins and needles are sticking in the skin; and burning sensations.
- An autonomic nerve controls muscles and organs regulating bodily functions that patients cannot control consciously, such as the heart, lungs, and digestive system. Symptoms include heat intolerance, gastrointestinal issues, loss of bowel and/or bladder control, sweating excessively, lack of expansion and contraction in the small blood vessels, dizziness from drops in blood pressure, and breathing difficulties if the muscles that control the lungs are affected.
Assessment and Diagnostics
To assess a patient for polyneuropathy, nurses should conduct a physical examination focused on patients’ movements, sense of touch, and pain. Patients may exhibit difficulty moving their hands, arms, legs, and/or feet. This may affect their ability to stand and walk, as well as the ability to do routine tasks such as writing or buttoning a shirt. Patients with polyneuropathy may also experience a loss of their sense of touch and no longer be able to feel cold or heat. They may also have numbness or a sensation that feels like they have pins and needles in their skin. Nurses should also be alert for pain, which patients with polyneuropathy may describe as throbbing and/or sharp, and the pain may occur in any part of the body.
Other ways to assess and diagnose polyneuropathy include blood and urine tests, lumbar puncture, imaging tests, spirometry, EMG, and nerve conduction studies. In some cases, skin and/or nerve biopsies may be useful. Often, polyneuropathy can be diagnosed based on the symptoms noted previously that can affect a patient’s motor, sensory, and/or autonomic nerves. Testing confirms the diagnosis and helps to identify the cause.
Diagnostics and Laboratory Values
An examination of patients with polyneuropathy may reveal the following diagnostics and laboratory results:
- Blood and urine tests may identify problems such as diabetes, kidney dysfunction, liver issues, vitamin deficiencies, and infections that can cause polyneuropathy.
- Lumbar punctures may find high protein levels in CSF and/or a low white blood cell count. These findings indicate that the patient may have a condition or disease, such as an autoimmune disorder, that can cause polyneuropathy.
- Imaging such as an MRI or CT scan may find that the patient has pinched nerves, a herniated disk, growths, or other problems that affect the nerves, causing polyneuropathy.
- EMG records the muscles’ electrical activity when contracted as well as during rest. This identifies abnormal muscular activity and helps determine if the patient’s problem is a muscle or nerve disorder. For patients with polyneuropathy, the EMG will find a nerve disorder.
- Nerve conduction studies measure the speed and strength of signals in the motor and sensory nerves and whether the myelin sheath or axons have been damaged. This information helps determine the severity of nerve damage experienced by patients with polyneuropathy.
- Spirometry can determine if the muscles involved in breathing have been affected. Spirometry is a pulmonary function test that measures the amount of air a patient can inhale and exhale, including how quickly the patient can exhale. During the test, the patient’s nostrils are closed with a clip, and their mouth is covered with a breathing mask. The patient is asked to breathe in deeply and hold the breath for a few seconds. Then they exhale, pushing the breath into the mask with as much force as possible.
- Nerve biopsies provide details about the nerve cells that are damaged and causing polyneuropathy. Nerve biopsies have the risk of further damaging nerve cells, however, so they typically are used in more severe cases when additional information is needed to understand the patient’s polyneuropathy.
- Skin biopsies provide information about the number of nerve endings patients have in their skin. For some patients with polyneuropathy, their condition is caused by damage to the nerve endings in the skin rather than damage in the nerves. A skin biopsy can determine this.
Nursing Care of the Patient with Polyneuropathy
When a patient’s polyneuropathy is caused by a health issue that can be treated and cured, nursing care should focus on helping the patient overcome the condition. For example, if a curable infection is the cause of a patient’s polyneuropathy, nurses should provide patients with the medications needed to eradicate the infection. If the patient’s polyneuropathy is caused by a vitamin deficiency, nursing care should focus on helping the patient develop a healthy diet, which may include appropriate dietary supplements, to overcome the vitamin deficiency.
If the patient’s polyneuropathy is caused by a condition or disease that cannot be cured, such as type I diabetes, nursing care should focus on education. Nurses should help patients with incurable polyneuropathy understand the disease and learn how to manage the symptoms. This may include medications, as well as teaching patients with polyneuropathy about lifestyle changes that can help them deal with the symptoms. For example, patients may need guidance to help them develop an exercise regimen and understand the need to make changes such as wearing loose-fitting clothes.
Recognizing Cues and Analyzing Cues
The cues of polyneuropathy will be found in the patient’s physical examination and test results. The cues from the physical examination may include a family history of neurological issues, as well as problems experienced by the patient, such as diabetes and alcoholism. The patient will also exhibit symptoms of polyneuropathy, which may include muscle weakness, loss of reflexes, coordination and balance issues, numbness, and low blood pressure.
Prioritizing Hypotheses, Generating Solutions, and Taking Action
Polyneuropathy should be prioritized based on the severity of symptoms, with priority given to more severe symptoms. For example, symptoms such as pain and the loss of bladder control should be prioritized over mild numbness. Nurses should work with other members of the patient’s health-care team to generate solutions. For example, a physical therapist can help a patient with polyneuropathy develop an exercise regimen to address problems such as muscle control. The nursing interventions appropriate for patients with polyneuropathy may include those in Table 17.16.
| Nursing Care | Rationale |
|---|---|
| Complete focused neurological assessments. | The patient’s ability to move different body parts, and issues such as muscle weakness, twitching, loss of reflexes, loss of bowel or bladder control, excessive sweating, heat intolerance, balance or coordination issues, numbness, burning sensations, and feelings of pins and needles may indicate polyneuropathy. |
| Monitor vital signs. | Changes in the patient’s vital signs, particularly blood pressure and breathing, may indicate health issues. |
| Administer medications. | Patients who have a condition that is causing polyneuropathy, such as an infection, should be treated with medications that can cure the condition and thereby relieve the polyneuropathy. For other patients, such as patients with diabetes, medications that can provide better control of diabetes or other conditions causing polyneuropathy can also improve the polyneuropathy. Patients with chronic polyneuropathy can be given medications that relieve the symptoms, such as pain relievers and topical treatments such as lidocaine cream. Some patients may benefit by taking antiseizure medicines, such as gabapentin and pregabalin, which can also relieve pain. Drugs used to treat depression, such as nortriptyline and duloxetine hydrochloride, can also treat pain by making the brain more capable of inhibiting pain signals. Particularly for patients with polyneuropathy who have a chronic condition and also experience depression, these drugs may be an effective treatment. |
| Provide breathing support. | Provide mechanical ventilation assistance to patients with polyneuropathy who struggle to breathe. |
| Coordinate with physical therapist. | Physical therapy can help patients with polyneuropathy learn exercises and techniques to strengthen their muscles and maintain a greater range of motion. For patients who have a disability as a result of polyneuropathy, physical therapy can help them learn to use assistive devices, such as a brace for their hand and/or foot, as well as a walker, cane, or wheelchair if needed. |
Evaluation of Nursing Care for the Patient with Polyneuropathy
The desired outcome for patients with polyneuropathy is relief from their symptoms. Nurses can evaluate whether symptoms of a patient with polyneuropathy have improved by checking their reflexes, lightly touching them and gauging their reaction, and monitoring their level of sensation to a pinprick. The steadiness of a patient’s gait can also indicate if they still have symptoms. If patients with polyneuropathy cannot be cured, their symptoms should be managed to improve quality of life.
Medical Therapies and Related Care
In some cases, polyneuropathy can be cured, and even if it isn’t curable, medical treatment can usually help patients with polyneuropathy. The medical therapies used to treat patients with polyneuropathy may include those in Table 17.17.
| Medical Therapy | Explanation of Care |
|---|---|
| Medications | May include medications that
|
| Provide breathing support | May include mechanical ventilation assistance. |
| Physical therapy | May include exercises and techniques to accomplish goals such as strengthen patients’ muscles and maintain a greater range of motion. For patients with polyneuropathy who have a disability, physical therapy can help them learn to use assistive devices, such as braces, walkers, canes, or wheelchairs. |
| Surgery | May include surgical procedures to remove tumors and treat other conditions that can be relieved with surgery. For patients who have surgery, help them prepare for surgery. After surgery, provide wound care, suture incisions, empty drains, change dressings and bandages, and apply heat/cold packs to assist with any swelling. |
| Scrambler therapy | This procedure uses electrodes to administer electrical stimulation through the patient’s skin to block the nerve endings from sending pain signals to the brain. |
| Spinal cord stimulation | This procedure implants neurostimulators into the patient’s body to emit low levels of electricity into the patient’s spinal cord, blocking pain signals to the brain. |
| Plasma exchange | This procedure purifies blood to help with conditions such as inflammation or an autoimmune condition. |
| Intravenous immune globulin | This therapy can strengthen the immune system. |
| Mental health support | Support can help patients who have a chronic, ongoing condition cope with the challenges of living with polyneuropathy. It may include medications to help with issues such as anxiety and depression. |