An 22 year old man is admitted to the emergency department after an automobile accident.
He has not lost a large amount of blood, but he suffers from a severe crush injury to his right leg. He is conscious and exhibits flaccid paralysis. Electrocardiogram results show a shortened QT interval and an increase in the PR interval (i.e., decreased duration of action potential and decreased conduction velocity). Laboratory results indicate that his serum potassium level has increased to a value of 6.5 mEq/L (normal: 3.5 to 5.0 mEq/L). This
increase in serum potassium causes which of the following?
A decreased net driving force for potassium from cells
B.Decreased intracellular potassium concentration
C.Hyperpolarization of the resting membrane potential
D.More negative Nernst potential for potassium
E.More negative resting membrane potential