Neuromuscular Disorders Fa23 PDF

Neuromuscular Disorders Tracy Lewis, MSN, RN  The Axon and the Neuromuscular Junction -Most of these disorders are due to a breakdown in either the motor neuron (axon) itself, neurotransmitters being able to cross the neuromuscular junction or the muscle's ability to respond t...

Neuromuscular Disorders Tracy Lewis, MSN, RN  The Axon and the Neuromuscular Junction -Most of these disorders are due to a breakdown in either the motor neuron (axon) itself, neurotransmitters being able to cross the neuromuscular junction or the muscle's ability to respond to the neurotransmitters. -These are along the neurological pathway from our brain to our muscle tissue. It is what tells our muscles to contract. -The impulse or action potential receives the message from other cells via the dendrites, uses the myelin sheath to travel down the axon body to the axon terminal. This is where neurotransmitters cross the neuromuscular junction into the muscle fiber allowing it to contract. -The myelin sheath (in yellow) is what makes the impulse quickly and smoothly travel down the axon body, if there is no myelin sheath or if it is damaged, the impulse may be slowed or may not get to the neuromuscular junction at all. Myasthenia Gravis - Pathophysiology -Disorder of transmission at the neuromuscular junction -Affects communication between the motor neuron and the innervated muscle cell -Antibody mediated loss of acetylcholine (ACh neurotransmitter) receptors impair transmission of impulses Myasthenia gravis - Who is at risk? Most common in young women aged 20-30 years and men over 50 years old, but may occur in men or women at any age Autoimmune disorder Involves muscle weakness and fatigability Symptoms worsen with muscle activity and lessen with rest Most common areas affected are eye and periorbital muscles Progresses to respiratory muscle weakness Myasthenia Gravis – Clinical manifestations Diplopia (double vision) Ptosis (drooping of upper eyelid) Weakness of muscles in face and throat Facial expression may be flat Dysphonia (voice impairment) Increased risk of choking and aspiration Generalized weakness Affects extremities and intercostal muscles, resulting in respiratory failure Respiratory failure requires intubation and mechanical ventilation Myasthenia gravis - Diagnosis Serum AChR antibody levels Acetylcholine receptor (AChR) antibodies are autoantibodies produced by the immune system that mistakenly target proteins called acetylcholine receptors that are located on the skeletal muscle fibers. This test detects and measures AChR antibodies in the blood Electromyography (EMG) Recording of the electrical activity of muscle tissue using electrodes attached to the skin or inserted into the muscle. Myasthenia gravis – Exacerbating factors Infection Surgery Medications: aminoglycosides, quinine, magnesium sulfate, procainamide, calcium channel blockers Pregnancy High environmental temperature Emotional stress Vigorous physical activity Abnormal thymus Myasthenia gravis – medical management Pharmacological Management Anticholinesterase drugs use to relieve symptoms – First line pyridostigmine bromide (Mestinon) an anticholinesterase that stops the breakdown of acetylcholine Treatment of autoimmune reaction Corticosteroids: prednisone Immunosuppressant drugs: azathioprine Slows the disease course, but they do not relieve symptoms rapidly Myasthenia gravis – Medical management Surgical management Thymectomy: surgical removal of the thymus Medical Management Immunomodulating treatments IV immune globulin (IVIG) Plasmapheresis (plasma exchange) A procedure in which the patient's blood is passed through a pheresis machine, where the filtered plasma is removed and discarded. Red blood cells along with replacement fluid such as flash frozen plasma (FFP) or albumin, are then re-infused into the patient Myasthenia Gravis – nursing considerations Adherence to prescribed medication regimen is very important Take medications as scheduled Have a watch or phone alarm to remind you to take medications Post drug schedule so family/caregivers know when it is to be given Plan strenuous activities when drug peaks Maintain an extra supply of medications Ensure understanding of Mechanism of Action of medications Myasthenia Gravis – nursing considerations Energy conservation Handicapped license plate Schedule activities to coincide with peak energy and strength Risk of aspiration Soft foods in gravy or sauces (mechanical soft diet) If choking, pureed food and thickened liquids may be needed Have suction equipment on hand Provide supplemental feedings Coincide meals with peak of medications Myasthenia gravis – nursing considerations Impaired vision Artificial tears Eyeglass can have crutches attached to help lift eyelids Patching of one eye can help with double vision Health teaching Allow for rest – conserve energy Medical alert bracelet CPR instruction to caregivers & family Use of home health equipment Myasthenia Gravis Resources Osmosis - Link Nurse Sarah RN - Link Real patient with MG - Link Guillain Barre Syndrome - Pathophysiology - Damage and destruction to myelin sheath of peripheral nerves - Without myelin, the speed of nerve conduction is reduced - Schwann cell that builds the myelin sheath is not affected, so remyelination can occur Guillain Barre syndrome – Who's at risk? Most common acquired inflammatory neuropathy – symptoms begin 1-3 weeks after the causative event occurred Immune mediated Medical emergency because of rapid development of respiratory paralysis Progresses over hours to days – peaking by week 2 and no longer than 4 weeks. Most make a full recovery after regrowth of the myelin sheath Regain of strength may take up to a year or longer Guillain Barre Syndrome – Exacerbating factors Bacterial infection Campylobacter jejuni Viral infections (most common antecedent event) Enteric viruses Herpes viruses (including cytomegalovirus and Epstein-Barr virus) Surgery Vaccination (rare) Guillain barre syndrome – clinical manifestations Begins in lower extremities and ascends "Ground to Butt" Flaccid weakness Dyskinesia Symmetrical paresthesia progresses to paralysis Respiratory paralysis severe enough to require intubation and mechanical ventilation occurs in 5-10% of patients Guillain Barre syndrome – Medical management Medical Emergency ICU monitoring required IV fluids for hydration Turn schedule and physical therapy DVT prophylaxis Medical Management IV Immune globulin (IVIG) Plasmapheresis Guillain Barre syndrome – nursing considerations Maintain respiratory function Enhancing physical mobility Providing adequate nutrition Improving communication Decreasing anxiety Reducing fatigue Monitoring and managing potential complications Promoting home, community based and transitional care Guillain Barre Resources Nurse Sarah RN - Link Evelyn’s Story - Link Parkinson's Disease - Pathophysiology Destruction of dopaminergic neuronal cells in the basal ganglia leads to... Depletion of dopamine stores and... Degeneration of dopaminergic pathway causing... Imbalance of excitatory and inhibitory neurotransmitters resulting in... Impairment of extrapyramidal tracts resulting in... Motor manifestations (tremors, rigidity, etc). Clinical manifestations result from a depletion of available dopamine (inhibitory neurotransmitters) Results in more excitatory neurotransmitters than inhibitory, leading to an imbalance that affects voluntary movement. Parkinson's Disease – Who is at risk? Results from a depletion of available dopamine (inhibitory neurotransmitters) Results in more excitatory neurotransmitters than inhibitory leading to an imbalance that affects voluntary movement. Slowly progressive, degenerative disorder Usually appears in the 5th decade of life, but cases have been diagnosed as early as 30 years of age Michael J. Fox was diagnosed at the age of 29 Men are affected more often than women Caused by environmental and genetic factors, may also be idiopathic 80% of patients with long disease course develop dementia Parkinson's disease – clinical manifestations Resting tremor is usually first manifestation Slow and coarse Maximal at rest, lessens during movement, and absent during sleep Bradykinesia (slowed movement) Muscle rigidity Postural instability Difficulty starting to walk, turning and stopping Shuffling gait Parkinson's disease – Medical Management Pharmacological management Carbidopa-levodopa Levodopa crosses the blood-brain-barrier (BBB) where it is converted to dopamine; carbidopa inhibits the breakdown of levodopa thereby increases avilable levodopa at the BBB Pramipexole (Mirapex), ropinirole (Requip) Dopamine agonists Parkinson's disease – Nursing considerations Encourage use of assistive devices Improving mobility Improving communication Enhancing self-care activities Support coping abilities Improving bowel elimination Monitoring and managing potential complications Improving nutrition Promoting home, community-based Enhancing swallowing and transitional care Resources for Parkinson’s Disease Nurse Sarah RN - Link Simple Nursing Medications - Link Michael J Fox speaking to Congress regarding PD - Link Amyotrophic lateral sclerosis (ALS) - Pathophysiology Motor neuron disease Progressive, no cure Combined degeneration of upper and lower motor neurons found in the corticospinal tracts, anterior horn cells, and bulbar motor nuclei "Lou Gehrig's Disease" Stephen Hawking was diagnosed in 1963 at age of 21, died in 2018 at age 76. Surviving that long is incredibly rare. ALS – Who is at risk? Most common motor neuron disease Most common among men with disease onset between 40 and 60 years old Beginning in one area of the body, motor weakness and deterioration spread until the entire body is involved, including ability to walk, talk, swallow and breathe. The entire sensory system: control and coordination of movement remains intact ALS – Clinical manifestations Intermittent, asymmetrical muscle Deep tendon stretch reflexes become cramps brisk and overactive Progressive weakness and fatigue Atrophy of hands or feet Weakness in muscle supplied by Progresses to forearms, shoulders and cranial nerves lower limbs Fasciculation(muscle twitching) Hoarseness, slurred speech, and incoordination dysphagia Spasticity Aspiration risk Emotional instability ALS – Nursing considerations Diagnosis is based on signs and symptoms No clinical or laboratory tests specific to this disease End of life issues include pain management, dyspnea and delirium Respiratory support Address issue before respiratory crisis Nonjudgmental support for their decision Death usually caused by failure of the respiratory muscles 50% of patient die within 3 years of onset 20% live 5 years 10% live 10 years ALS – Nursing considerations Symptom management/supportive care Decrease spasticity Decrease saliva production Reduce muscle cramps Health teaching of supportive devices Motorized wheelchair Computer-assisted communication devices Sip and puff switch for control of devices ALS Resources Level up RN - ALS/MG & GB - Link Ice Bucket Challenge - Link Khan Academy - Link Systemic Lupus Erythematosus (SLE) - Pathophysiology The immune system mistakes component of the cell nucleus as foreign Formation of autoantibodies and large immune complexes B-cell overproduction of antibodies The autoantibodies can directly damage tissues or combine with corresponding antigens to form tissue-damaging immune complexes These autoantibodies and immune complexes get trapped in capillaries Begin to attack host cells in the capillaries. Direct attack on: Platelets Coagulation factors Red blood cell surface antigens SLE – Who is at risk? Chronic, multisystem, inflammatory autoimmune disorder Occurs predominantly in young women Estrogen may contribute to development of SLE More common in African American populations Environmental triggers UV light exposure Cigarette smoking Medications Viral infections Stress SLE – Clinical Manifestations Hematologic – anemia, leukopenia, thrombocytopenia Musculoskeletal – arthralgia, arthritis Dermatologic – butterfly rash, discoloration of skin, hair loss Cardiovascular – pericarditis, myocarditis, hypertension Pulmonary – pleural effusion Renal – lupus nephritis, proteinuria, hematuria Neuropsychiatric – psychosis, confusion, seizures Gastrointestinal – abdominal pain, nausea, vomiting SLE – Diagnosis and Management Diagnosis: ACR Criteria for Classifying Systemic Lupus Erythematosus: must meet 4 of 11 criteria (next slide) CBC: anemia, thrombocytopenia, leukopenia Antinuclear antibodies (ANA): positive in 95% of patients Pharmacological management: Antimalarial agent: hydroxychloroquine Monoclonal antibodies: belimumab (Benlysta) Corticosteroids: prednisone SLE – Diagnosis & Management – 2019 Criteria SLE – Nursing Considerations Impaired skin integrity Health promotion Frequent health screenings Increased risk for cardiovascular disease Cardiac diet Knowledge deficit Medication regimen Increased risk of infection due to corticosteroid therapy Renal complications Monitor for decreased urine output Change in urine characteristics SLE Resources Nurse Sarah RN - Link Patient story - Link Osmosis - Link Multiple Sclerosis - Pathophysiology Sensitized T-cells cross the blood- brain-barrier (BBB), stay in the CND and promote infiltration of other agents that cause damage resulting in.... Immune system attack, causing inflammation which leads to... Localized areas of demyelination (plaques) occur MS – Who is at risk? Immune mediated disorder Demyelinating disorder characterized by inflammation and destruction of CNS myelin Peripheral nervous system is spared Causes is unknown Effects three times as many women as men May occur at any age, by peak onset is between 20 and 50 years of age Lesions are hard sclerotic patches called plaques MS – Clinical Manifestations Fatigue is a major problem Paresthesias in one or more extremities, in the truck, or on one side of the face progressing to paralysis Weakness or clumsiness of a leg or hand Dysphagia Nystagmus and diplopia (blurred vision) Urinary retention and spasms Constipation Pain due to lesions on sensory pathways MS – Exacerbating Factors of Fatigue Heat Avoid hot temperatures Depression Anemia Deconditioning OT and PT Balance of rest and activities, good nutrition, healthy lifestyle Avoid alcohol and cigarette smoking Medication regimen MS – Medical Management No cure, treatment is based on symptoms relief, delay progression of disease, manage chronic conditions and treat acute exacerbations Pharmacological management Disease modifying therapies: reduce relapse, duration and number/size of plaques Interferons (interferon beta-1a and interferon beta-1b) Glatiramer acetate (Copaxone) Reduces the course of MS Decreases the number of plaques Increases time between relapses Methylprednisolone Decreases inflammation, reduces relapse MS – Medical management Pharmacological management (continued) Symptom management: reduce symptoms Baclofen Reduce muscle spasms Amantadine Treats fatigue Gabapentin Pain paresthesias (neuropathy) MS – Nursing considerations Promote Physical Mobility exercise minimizing spasticity and contractures activity and rest nutrition Preventing Falls Manage Fatigue Strengthening Coping Mechanisms Monitoring and Managing Potential Complications Promoting Home, Community-Based and Transitional Care Education MS Resources Mayo Clinic - Link Nurse Sarah RN - Link Khan Academy - Link Fibromyalgia – Pathophysiology & Who is at risk Most common in women Often associated with: Depression Anxiety Sleep disorders Stress Chronic pain syndrome may have viral and bacterial causes, may be autoimmune disorder and characterized by: Fatigue Stiffness Muscle aches Medical management Diagnosis: Generalized blood testing (CBC, chem profile, sed rate) No definitive test to diagnose Pharmacological management Lyrica (pregabalin) Anti-seizure medication used for neuropathic pain Can cause Steven-Johnsons syndrome, thrombocytopenia and suicidal ideations Do not suddenly stop taking this medication NSAIDs and tricyclic antidepressants also used Medical management Teach to reduce stress, healthy diet and exercise Degenerative Disc Disease – pathophysiology & who is at risk One of the most common complaints in primary care Acute or chronic pain usually accompanied with fatigue May complain of pain shooting down leg or low back pain Causes: Injury Obesity Posture and structure Disc disease, fractures DDD – Medical Management Diagnosis Xray of the spine MRI Myelogram IV dye injected around spinal cord for direct visualization Visualization of disc herniation or compression Pharmacological management Flexeril, Elavil NSAIDs, Tylenol DDD – Medical management Non-surgical management Heat therapy Spinal manipulation from a chiropractor Surgical management: Microdiscectomy - removal of herniated or extruded fragments of intervertebral disc material Laminectomy - Removal of bone to expose neural elements of the spinal canal to identify and remove pathologic tissue and relieve compression of the spinal cord Discectomy with fusion- Fusion of the vertebral spinous process with a bone graft (from donor or autograft from iliac crest), with the object of spinal fusion being to bridge over the defective disc to stabilize the spine and reduce rate of recurrence Other resources Simple Nursing - Neurological Disorders - Link