Neuromuscular disorders

Question 1

What is hyperkalemic periodic paralysis (HyperPP)?

Answer 1

An autosomal dominant disorder characterized by flaccid paralysis and increased serum potassium, often precipitated by cold, hunger, or stress

Question 2

What are the anaesthetic considerations for HyperPP?

Answer 2

Avoid depolarizing neuromuscular blockers and potassium-containing fluids. Preoperative potassium depletion may be necessary. Continuous ECG monitoring and availability of calcium for emergency treatment.

Question 3

What is the cause of myasthenia gravis?

Answer 3

An autoimmune disease where antibodies target nicotinic acetylcholine receptors at the neuromuscular junction, leading to muscle weakness.

Question 4

What are the anaesthetic considerations for myasthenia gravis?

Answer 4

Use depolarizing agents with caution (patients may need a higher dose). Avoid cholinesterase inhibitors due to the risk of cholinergic crisis. Monitor for respiratory failure and be prepared for postoperative ventilation.

Question 5

What causes Eaton-Lambert syndrome?

Answer 5

Antibodies against presynaptic calcium channels leading to impaired acetylcholine release, causing weakness that improves with exercise.

Question 6

What are the anaesthetic considerations for Eaton-Lambert syndrome?

Answer 6

Sensitivity to both depolarizing and non-depolarizing neuromuscular blocking agents. Anti-cholinesterases can be used. Prepare for possible postoperative ventilation.

Question 7

What is critical illness polyneuropathy?

Answer 7

A condition acquired during critical illness, marked by muscle weakness, atrophy, and difficulty weaning from ventilators, typically due to axonal degeneration.

Question 8

What are the anaesthetic considerations for critical illness polyneuropathy?

Answer 8

Avoid prolonged use of non-depolarizing neuromuscular blockers, particularly with high-dose steroids. Avoid depolarizing agents to prevent hyperkalemia and cardiac arrest

Question 9

What is diabetic polyneuropathy?

Answer 9

A condition caused by damage to sensory, motor, and autonomic nerves in diabetes, often resulting in widespread or focal neuropathy.

Question 10

What are the anaesthetic considerations for diabetic polyneuropathy?

Answer 10

Be mindful of autonomic instability and gastroparesis. Ensure temperature control to prevent hypothermia, and consider invasive monitoring during surgery.

Question 11

What is Guillain-Barré syndrome?

Answer 11

An immune-mediated polyneuropathy, often triggered by a viral or bacterial infection, causing ascending weakness and respiratory compromise

Question 12

What are the anaesthetic considerations for Guillain-Barré syndrome?

Answer 12

Avoid depolarizing neuromuscular blockers. Prepare for rapid respiratory deterioration, intubation, and invasive monitoring. Epidural anaesthesia may be helpful for reducing opioid use postoperatively.

Question 13

What are common triggers for Guillain-Barré Syndrome?

Answer 13

GBS is often triggered by infections, particularly respiratory or gastrointestinal infections such as Campylobacter jejuni (bacterial), cytomegalovirus (CMV), Epstein-Barr virus (EBV), and Zika virus.

Question 14

What is the pathophysiology of Guillain-Barré Syndrome?

Answer 14

GBS is characterized by autoimmune-mediated demyelination of peripheral nerves, which results in ascending muscle weakness. Inflammatory attacks on the myelin sheath or sometimes the axons themselves cause dysfunction in nerve conduction.

Question 15

What are the typical clinical features of Guillain-Barré Syndrome?

Answer 15

The hallmark of GBS is ascending muscle weakness, starting in the lower limbs and progressing upward. Sensory disturbances (numbness, tingling) and autonomic dysfunction (e.g., BP fluctuations, tachycardia) can also occur. Respiratory failure is a common complication

Question 16

Phases of Guillain-Barré Syndrome

Answer 16

GBS typically progresses in three phases:

Acute phase: Rapid progression of muscle weakness (usually over 2-4 weeks).
Plateau phase: Stabilization of symptoms.
Recovery phase: Gradual recovery, which can take weeks to months.

Question 17

What is the most significant anaesthetic concern for patients with Guillain-Barré Syndrome?

Answer 17

Respiratory compromise is a major concern due to the potential for ascending paralysis of respiratory muscles, which may require intubation and mechanical ventilation. Respiratory function should be closely monitored.

Question 18

What type of monitoring is recommended for patients with Guillain-Barré Syndrome during surgery?

Answer 18

Invasive monitoring is recommended, especially for blood pressure and heart rate, due to the risk of autonomic instability. Neurological monitoring may also be required to track any changes in muscle strength.

Question 19

What are the anaesthetic considerations for neuromuscular blockers in Guillain-Barré Syndrome?

Answer 19

Avoid depolarizing neuromuscular blockers (e.g., suxamethonium), as GBS patients may be at risk for hyperkalemic cardiac arrest. Non-depolarizing neuromuscular blockers should be used with caution, as GBS may increase sensitivity to them

Question 20

How does temperature affect patients with Guillain-Barré Syndrome?

Answer 20

Temperature control is essential because temperature extremes can exacerbate the condition. Hyperthermia can worsen the demyelination process, while hypothermia may increase muscle stiffness and weakness.

Question 21

Is epidural anaesthesia recommended for patients with Guillain-Barré Syndrome?

Answer 21

Epidural anaesthesia can be beneficial to avoid opioid use, which may exacerbate respiratory and motor symptoms. However, caution is needed in patients with autonomic dysfunction due to the potential for hypotension.

Question 22

: What are some anaesthetic complications in Guillain-Barré Syndrome?

Answer 22

Complications may include aspiration risk due to bulbar weakness, autonomic instability (leading to sudden BP fluctuations or arrhythmias), and prolonged neuromuscular blockade due to altered sensitivity to muscle relaxants.

Question 23

Q: How do patients with Guillain-Barré Syndrome typically recover?

Answer 23

A: Recovery can take months to years, with most patients experiencing significant improvement. Some may have long-term residual weakness or autonomic dysfunction. Rehabilitation is crucial for regaining strength and function.

Question 24

What should be considered in postoperative care for Guillain-Barré Syndrome patients?

Answer 24

Postoperative care should include monitoring for respiratory function, neurological status, and cardiac stability. Ventilatory support may be necessary, and care should be taken to avoid hypothermia and excessive muscle stimulation.