Weakness: Difference between revisions
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==Background== | ==Background== | ||
Determine if patient has actual neuromuscular weakness (suggesting CNS | Determine if patient has actual neuromuscular weakness (suggesting CNS dysfunction) or non-neuromuscular weakness. | ||
== | ==Clinical Features== | ||
===History === | ===History=== | ||
*'''True motor weakness (neuromuscular weakness)? Bilateral or unilateral (distribution of weakness)?''' | *'''True motor weakness (neuromuscular weakness)? Bilateral or unilateral (distribution of weakness)?''' | ||
**Bilateral weakness: | **Bilateral weakness: | ||
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***Weakness involving both central and peripheral nervous system? Inflammatory/Autoimmune or toxic/metabolic | ***Weakness involving both central and peripheral nervous system? Inflammatory/Autoimmune or toxic/metabolic | ||
***Discrete sensory level and/or bladder dysfunction? [[Spinal Cord Lesion]] | ***Discrete sensory level and/or bladder dysfunction? [[Spinal Cord Lesion]] | ||
***Involvement of proximal | ***Involvement of proximal > distal musculature? Myopathy | ||
**Unilateral weakness: [[CVA]], [[TIA]] | **Unilateral weakness: [[CVA]], [[TIA]] | ||
*'''If non-neuromuscular weakness''' then BROAD differential, obtain: | *'''If non-neuromuscular weakness''' then BROAD differential, obtain: | ||
**ECG, CBC, Chem10, LFTs, blood cultures, UA/ | **[[ECG]], CBC, Chem10, [[LFTs]], blood cultures, [[UA]]/urine culture, drug levels, [[CXR]], Consider [[Head CT]] ([[focal deficit]], [[AMS|altered]], history of cancer, [[anticoagulation]] with minor trauma) | ||
*'''Onset of weakness sudden or gradual?''' | *'''Onset of weakness sudden or gradual?''' | ||
**Sudden suggests vaso-occlusive etiology [[CVA]]/[[TIA]] | **Sudden suggests vaso-occlusive etiology [[CVA]]/[[TIA]] | ||
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*'''Significant event surrounding onset of weakness?''' | *'''Significant event surrounding onset of weakness?''' | ||
**[[Seizure]] prior to weakness? Todd’s paralysis | **[[Seizure]] prior to weakness? Todd’s paralysis | ||
**Migraine headache? Complicated migraine | **Migraine headache? Complicated [[migraine]] | ||
**Sudden onset of severe headache? [[SAH]] | **Sudden onset of severe headache? [[SAH]] | ||
**Trauma? Epidural or [[Subdural Hematoma]] | **Trauma? Epidural or [[Subdural Hematoma]] | ||
**Severe migratory neck or chest pain? Arterial dissection syndromes | **Severe migratory neck or chest pain? [[vertebral and carotid artery dissection|Arterial dissection syndromes]] | ||
*'''Temporal pattern to weakness? Fluctuating or fixed weakness?''' | *'''Temporal pattern to weakness? Fluctuating or fixed weakness?''' | ||
**Weakness with repetitive motions? Neuromuscular junction pathology like [[Myasthenia Gravis]] | **Weakness with repetitive motions? Neuromuscular junction pathology like [[Myasthenia Gravis]] | ||
*'''Associated symptoms?''' | *'''Associated symptoms?''' | ||
**Headache: SAH, epidural/SDH, complicated migraines (young females), not usually stroke/TIA (unless high intracranial pressure) | **[[Headache]]: [[SAH]], epidural/[[SDH]], complicated migraines (young females), not usually stroke/TIA (unless high intracranial pressure) | ||
**Vision changes: Posterior circulation stroke, [[Myasthenia Gravis]] | **[[visual disturbances|Vision changes]]: Posterior circulation [[stroke]], [[Myasthenia Gravis]] | ||
**Shortness of breath: | **[[Shortness of breath]]: cardiovascular etiology | ||
**Chest pain or neck pain: Acute | **[[Chest pain]] or [[neck pain]]: Acute [[vertebral and carotid artery dissection|carotid/vertebral]]/[[aortic dissection]], [[AMI]] | ||
**Abdominal or back pain: | **[[abdominal pain|Abdominal]] or [[back pain]]: | ||
***with alteration of bowel habits? [[Botulism]], organophosphate poisoning, toxins, [[Guillain-Barre Syndrome]], [[Electrolyte Imbalance]]. | ***with alteration of bowel habits? [[Botulism]], organophosphate poisoning, toxins, [[Guillain-Barre Syndrome]], [[Electrolyte Imbalance]]. | ||
***with lower extremity weakness? [[AAA]] with spinal cord infarction | ***with lower extremity weakness? [[AAA]] with spinal cord infarction | ||
***Back pain with unilateral weakness? Herniated disk with nerve impingement | ***[[Back pain]] with unilateral weakness? Herniated disk with nerve impingement | ||
***Bilateral weakness with sensory level s/p trauma? SCI, [[Cauda Equina Syndrome]] | ***Bilateral weakness with sensory level s/p trauma? [[spinal cord injury|SCI]], [[Cauda Equina Syndrome]] | ||
**Nausea/vomiting: sign of ↑ ICP, can lead to electrolyte imbalances | **[[Nausea/vomiting]]: sign of [[elevated ICP|↑ ICP]], can lead to [[electrolyte imbalances]] | ||
**Rash: Dermatomyositis | **Rash: [[Dermatomyositis]] | ||
===Physical Exam === | ===Physical Exam=== | ||
Focus on clarifying if patient has true loss of strength and determining distribution of deficits. Check for trauma, carotid bruits, thyroid enlargement, irregular rhythm, unequal pulses, rashes or ticks. | Focus on clarifying if patient has true loss of strength and determining distribution of deficits. Check for trauma, carotid bruits, thyroid enlargement, irregular rhythm, unequal pulses, rashes or ticks. | ||
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| '''End-plate/muscle'''|||||||||| | | '''End-plate/muscle'''|||||||||| | ||
|- | |- | ||
| Motor end plate|| | | Motor end plate||Ocular, bulbar and descends, fatigable ||No||Nl/diminished||Nl/parethesias||No | ||
|- | |- | ||
| Muscle||Proximal > distal ||No||Nl/diminished||Normal||+/- | | Muscle||Proximal > distal ||No||Nl/diminished||Normal||+/- | ||
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==Evaluation== | ==Evaluation== | ||
===Workup === | ===Workup=== | ||
'''On all patients:''' | '''On all patients:''' | ||
*CBC (anemia) | *CBC (anemia) | ||
*Chem 10 ([[electrolyte disturbance]], [[hypoglycemia]], uremia) | *Chem 10 ([[electrolyte disturbance]], [[hypoglycemia]], uremia) | ||
*[[ECG]] (Ischemia,hypo/[[hyperkalemia]]) | *[[ECG]] ([[myocardial ischemia|Ischemia]], [[hypokalemia|hypo]]/[[hyperkalemia]]) | ||
'''Consider:''' | '''Consider:''' | ||
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*ESR | *ESR | ||
*[[CXR]] and [[UA]] (if infectious symptoms or elderly) | *[[CXR]] and [[UA]] (if infectious symptoms or elderly) | ||
*FVC (if evidence of | *FVC (if evidence of respiratory compromise, i.e. Myasthenia, GBS) | ||
*[[CT head]] (if focal findings, [[ | *[[CT head]] (if focal findings, [[altered mental status]], history of cancer, history of any trauma in patient on anticoagulation) | ||
*[[LP]] (CNS infection, GBS) | *[[LP]] (CNS infection, GBS) | ||
==Management== | ==Management== | ||
===Intubation Indications === | ===[[Intubation]] Indications=== | ||
*Severe fatigue | *Severe fatigue | ||
*Inability protect airway | *Inability protect airway | ||
*Rapidly increasing PaCO2 | *Rapidly increasing PaCO2 | ||
*Hypoxemia despite O2 | *[[Hypoxemia]] despite O2 | ||
*FVC <12 mL/kg | *FVC <12 mL/kg | ||
*Neg Insp Force <20 cm H2O | *Neg Insp Force <20 cm H2O | ||
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*Depends on process | *Depends on process | ||
**If normal initial workup, make sure has no respiratory compromise | **If normal initial workup, make sure has no respiratory compromise | ||
==See Also== | |||
==External Links== | |||
==References== | ==References== | ||
<references/> | |||
[[Category:Neurology]] | [[Category:Neurology]] | ||
[[Category:Symptoms]] |
Revision as of 16:08, 4 March 2020
Background
Determine if patient has actual neuromuscular weakness (suggesting CNS dysfunction) or non-neuromuscular weakness.
Clinical Features
History
- True motor weakness (neuromuscular weakness)? Bilateral or unilateral (distribution of weakness)?
- Bilateral weakness:
- Symmetric ascending paralysis? Guillain-Barre Syndrome
- Weakness involving both central and peripheral nervous system? Inflammatory/Autoimmune or toxic/metabolic
- Discrete sensory level and/or bladder dysfunction? Spinal Cord Lesion
- Involvement of proximal > distal musculature? Myopathy
- Unilateral weakness: CVA, TIA
- Bilateral weakness:
- If non-neuromuscular weakness then BROAD differential, obtain:
- ECG, CBC, Chem10, LFTs, blood cultures, UA/urine culture, drug levels, CXR, Consider Head CT (focal deficit, altered, history of cancer, anticoagulation with minor trauma)
- Onset of weakness sudden or gradual?
- Significant event surrounding onset of weakness?
- Seizure prior to weakness? Todd’s paralysis
- Migraine headache? Complicated migraine
- Sudden onset of severe headache? SAH
- Trauma? Epidural or Subdural Hematoma
- Severe migratory neck or chest pain? Arterial dissection syndromes
- Temporal pattern to weakness? Fluctuating or fixed weakness?
- Weakness with repetitive motions? Neuromuscular junction pathology like Myasthenia Gravis
- Associated symptoms?
- Headache: SAH, epidural/SDH, complicated migraines (young females), not usually stroke/TIA (unless high intracranial pressure)
- Vision changes: Posterior circulation stroke, Myasthenia Gravis
- Shortness of breath: cardiovascular etiology
- Chest pain or neck pain: Acute carotid/vertebral/aortic dissection, AMI
- Abdominal or back pain:
- with alteration of bowel habits? Botulism, organophosphate poisoning, toxins, Guillain-Barre Syndrome, Electrolyte Imbalance.
- with lower extremity weakness? AAA with spinal cord infarction
- Back pain with unilateral weakness? Herniated disk with nerve impingement
- Bilateral weakness with sensory level s/p trauma? SCI, Cauda Equina Syndrome
- Nausea/vomiting: sign of ↑ ICP, can lead to electrolyte imbalances
- Rash: Dermatomyositis
Physical Exam
Focus on clarifying if patient has true loss of strength and determining distribution of deficits. Check for trauma, carotid bruits, thyroid enlargement, irregular rhythm, unequal pulses, rashes or ticks.
Location | Weakness | Bowel/Bladder | Reflexes | Sensory | Pain |
Upper motor neuron | |||||
Brain | Variable | Increased | Diminished | No | |
Brainstem | "crossed" findings - ipsilateral cranial nerve weakness and contralateral hemiparesis | ||||
Cord | Fixed level | Yes | Increased | Diminished | +/- |
Lower motor neuron | |||||
Nerve | Distal > proximal and ascends | No | Diminished | Nl/parethesias | No |
End-plate/muscle | |||||
Motor end plate | Ocular, bulbar and descends, fatigable | No | Nl/diminished | Nl/parethesias | No |
Muscle | Proximal > distal | No | Nl/diminished | Normal | +/- |
Differential Diagnosis
Weakness
- Neuromuscular weakness
- Upper motor neuron:
- CVA
- Hemorrhagic stroke
- Multiple sclerosis
- Amyotrophic Lateral Sclerosis (ALS) (upper and lower motor neuron)
- Lower motor neuron:
- Spinal and bulbar muscular atrophy (Kennedy's syndrome)
- Spinal cord disease:
- Infection (Epidural abscess)
- Infarction/ischemia
- Trauma (Spinal Cord Syndromes)
- Inflammation (Transverse Myelitis)
- Degenerative (Spinal muscular atrophy)
- Tumor
- Peripheral nerve disease:
- Neuromuscular junction disease:
- Muscle disease:
- Rhabdomyolysis
- Dermatomyositis
- Polymyositis
- Alcoholic myopathy
- Upper motor neuron:
- Non-neuromuscular weakness
- Can't miss diagnoses:
- ACS
- Arrhythmia/Syncope
- Severe infection/Sepsis
- Hypoglycemia
- Periodic paralysis (electrolyte disturbance, K, Mg, Ca)
- Respiratory failure
- Emergent Diagnoses:
- Symptomatic Anemia
- Severe dehydration
- Hypothyroidism
- Polypharmacy
- Malignancy
- Aortic disease - occlusion, stenosis, dissection
- Other causes of weakness and paralysis
- Acute intermittent porphyria (ascending weakness)
- Can't miss diagnoses:
Evaluation
Workup
On all patients:
- CBC (anemia)
- Chem 10 (electrolyte disturbance, hypoglycemia, uremia)
- ECG (Ischemia, hypo/hyperkalemia)
Consider:
- CK (mypoathies)
- ESR
- CXR and UA (if infectious symptoms or elderly)
- FVC (if evidence of respiratory compromise, i.e. Myasthenia, GBS)
- CT head (if focal findings, altered mental status, history of cancer, history of any trauma in patient on anticoagulation)
- LP (CNS infection, GBS)
Management
Intubation Indications
- Severe fatigue
- Inability protect airway
- Rapidly increasing PaCO2
- Hypoxemia despite O2
- FVC <12 mL/kg
- Neg Insp Force <20 cm H2O
Disposition
- Depends on process
- If normal initial workup, make sure has no respiratory compromise