Mrs. Bush, a 70-year-old woman, is admitted to the hospital. Her history states that she has been suffering from diarrhea for three weeks. On admission, she complains of severe fatigue and muscle weakness. A blood chemistry study yields the following information: Na+ 142 mEq/L; K+ 1.5 mEq/L; Cl− 92 mEq/L; PCO2 32 mm Hg. Which electrolytes are within normal limits? Which are so abnormal that the patient has a medical emergency? Which of the following represents the greatest danger to Mrs. Bush?

(a) A fall due to her muscular weakness,

(b) Edema,

(c) Cardiac arrhythmia and cardiac arrest.