MSFinals-5422

MSFinals-5422

A 25-year-old female presents to the emergency department with palpitations. Her ECG reveals first-degree heart block, tall P-waves, and flattened T-waves. Upon arterial blood gas analysis, her results are as follows: pH 7.55 (normal range 7.35-7.45), HCO3- 30 mmol/L (normal range 22-26 mmol/L), pCO2 5.8kPa (normal range 4.5-6kPa), p02 11kPa (normal range 10-14kPa), and Chloride 85mmol/L (normal range 95-108mmol/L). What is the underlying cause of her presentation?