Hyper/Hypomagnasemia

Question 1

What can cause hypomagnasemia?

Answer 1

Mg is secreted in the GI tract, so excess losses in diarhhoea, stoma or fistula will cause low K.
Alcoholism
Undernutrition

Drugs: chronic PPIs and diuretics

Secondary to hypocalcaemia and hypokalaemia.

Question 2

What is Trousseau sign?

Answer 2

Carpopedal spasm of hand and wrist occuring after wearing inflated BP cuff.
Suggests hypocalcaemia

Question 3

What is Chvostek sign?

Answer 3

Twitch of facial muscle when tap on cheek in front of ear.

Assoc with hypocalcaemia.

Question 4

How to manage hypomagnasemia?

Answer 4

Severe: iv or im magnesium sulphate

Mild:oral megnesium glycerolphosphate

Question 5

ECG changes assoc with hypomagnesemia?

Answer 5

Prolonged PR interval
Prolonged QT interval
Atrial and ventricle ectopy
Predisposition to V and torsades de pointes

Question 6

ECG changes assoc with hypermagnasemia?

Answer 6

Shorted PR and QTc
Prolonged QRS
Peaked T waves, flattened P wave
Complete AV block and asystole

Question 7

Management for hypermagnasemia?

Answer 7

Discontinue Mg intake

1. Dialysis
2. Calcium chloride for arrhythmias.
3. IV saline and frusemide