Kailas,66yrs previously healthy man is admitted to a hospital because of a closed head injury and ruptured spleen following a road side automobile accident.During the first 4 days of hospitalization,following laparotomy and splenectomy,he receives 5% dextrose 0.5% normal saline solution at a rate of 125mL/h.Recorded daily fluid outputs include 450 to 600mL of nasogastric drainage and 700 to 1000 mL of urine.The patient is somnolent but easily aroused until the morning of the 5th hospital day,when he noted to be in deep coma.By the after-noon,he begins having seizures.The following laboratory data are obtained: Serum electrolytes(meq L):Na+128:K+1.8;Cl-94;HCO3-19.Serum osmolality : 260mOsm/L; Urine electrolytes (meq/L):Na+61;K+18.Which of the following about diagnosis or treatment of this patient's is true:

• A. Secondary to metabolic acidosis their is hypokalemia
• B. Emergency carotid arteriogram to be done
• C. IV infusion of 20ml of 50%MgSO4 given for 4 hrs.
• D. A small quantity of hypertonic saline to be given