Exogenous sources such as ingestion of potassium supplements and salt substitutes, blood transfusions, IV potassium administration and high dose penicillin therapy must also be considered. Also consider water softeners as a potential source of exogenous potassium. Intracellular to extracellular shift. Acidosis, digitalis, overdose, insulin deficiency, or rapid increase of blood osmolality. Secondary to hemolysis of blood sample or prolonged tourniquet time.
Most important effect is a change in cardiac excitability.
ECG shows sequential changes with a rising serum potassium level. Eventually the QT interval prolongs and leads to a sine-wave pattern. L. Other findings include paresthesias, weakness, areflexia, and ascending paralysis. This can be repeated twice at 5-minute intervals if no response. Administration of calcium may cause digitalis toxicity in patients receiving digitalis therapy and should not be used in the face of digitalis toxicity.