Review Question - QID 215187

A 25-year-old woman presents to the emergency department with painful spasms in her arms. She states that her symptoms have been worsening over the past several days and also endorses numbness around her mouth. The patient has a history of patellofemoral syndrome and plantar fasciitis which is not responding to therapy given that the patient has refused to reduce her daily jogging. She normally jogs 5 miles a day and adds an additional 3 miles for every meal she eats. Her temperature is 97.6°F (36.4°C), blood pressure is 114/77 mmHg, pulse is 80/min, respirations are 12/min, and oxygen saturation is 98% of room air. Physical exam reveals a young woman with thinning hair. Her BMI is 24 kg/m^2. Her heart rate is regular and her breath sounds are clear. An ECG is performed as seen in Figure A and serum potassium is 2.7 mEq/L. The patient is given 2 liters of normal saline and potassium repletion. Laboratory studies are subsequently ordered 2 hours later as seen below:

Hemoglobin: 10 g/dL
Hematocrit: 33%
Leukocyte count: 6,600/mm^3 with normal differential
Platelet count: 297,000/mm^3

Serum:
Na+: 137 mEq/L
Cl-: 99 mEq/L
K+: 2.9 mEq/L
HCO3-: 28 mEq/L
Blood urea nitrogen (BUN): 20 mg/dL
Glucose: 99 mg/dL
Creatinine: 1.1 mg/dL
Ca2+: 8.0 mg/dL

Which of the following is the most appropriate initial management for this patient?