Sun21November0735PM 2

Is it true that suxamethonium is associated with hyperkalaemia in the following?

True / False

Tetanus Correct

Liver failure Correct

Immediately following burns Correct

Prolonged immobilisation Correct

Myopathy Correct

Explanation

Suxamethonium is a short-acting depolarising muscle relaxant. It is usually used to allow rapid intubation of the trachea or to provide short periods of neuromuscular blockade.

Hyperkalemic responses to suxamethonium have been associated with:

Burns

Certain neuromuscular diseases (including spinal cord injury, upper motor lesions, peripheral nerve injury, tetanus, and muscular dystrophy, myopathy)

Closed-head injury

Malignancy

Abdominal sepsis

Hypovolaemic shock

Long term neuromuscular blockade, and

Prolonged immobilisation.

The mechanism is thought to involve up-regulation of acetylcholine receptors. This does not occur immediately after burns, but suxamethonium should be avoided after 12-24 hours. A normal increase of potassium serum concentration on administration of suxamethonium is 0.5 mmol/L, this can be exaggerated in renal failure.