Normal serum potassium is between 3.5 and 5.2 mmol/l in children over 1 year. In children under 1 year, values up to 6.5 mmol/l are accepted.
Acidosis exacerbates hyperkalaemia.
Angiotensin-converting enzyme (ACE) inhibitors block the conversion of angiotensin I to angiotensin II. They are increasingly becoming first line therapy for hypertension in both adult and paediatric practice. A well recognised consequence of ACE inhibitor therapy is hyperkalaemia.
Salbutamol is the first line therapy for hyperkalaemia. It is effective when given as a nebuliser and therefore can be administered before intravenous access has been obtained. It acts by stimulating the transport of potassium into cells, thereby reducing serum potassium levels. However there is no net loss of potassium from the body. This can be achieved by the oral or rectal administration of an ion-exchange resin such as calcium resonium or by dialysis. The effect of salbutamol on serum potassium should also be remembered when administering large doses to asthmatic patients - potassium supplementation is likely to be needed.
Hyperkalaemia causes various conduction abnormalities. For further information go to http://lifeinthefastlane.com/ecg-library/basics/hyperkalaemia/
For an explanation of ECG changes click here.