Metabolic alkalosis mechanisms and compensationDownloads

A 52-year-old woman is brought to the emergency department by her husband because of weakness, abdominal pain, and a productive cough for 4 days. She also reports increased urination for the past 2 days. This morning, she had nausea and five episodes of vomiting. She has type 1 diabetes mellitus and hypertension. Current medications include insulin and lisinopril. She admits to have forgotten to take her medication in the last few days. Her temperature is 38.4°C (101.1°F), pulse is 134/min, respirations 31/min, and blood pressure is 95/61 mm Hg. Examination shows dry mucous membranes and decreased skin turgor. Abdominal examination shows diffuse tenderness with no guarding or rebound. Bowel sounds are normal. Laboratory studies show: Serum Na+ 139 mEq/L K+ 5.3 mEq/L Cl- 106 mEq/L Glucose 420 mg/dL Creatinine 1.0 mg/dL Urine Blood negative Glucose 4+ Ketones 3+ Arterial blood gas analysis on room air shows: pH 7.12 pCO2 17 mm Hg pO2 86 mm Hg HCO3- 12 mEq/L Which of the following is the most likely underlying cause of this patient's increased potassium?

A 47-year-old man with a history of alcoholism undergoes an upper endoscopy, which reveals a superficial mucosal tear in the distal esophagus. Laboratory results show a metabolic alkalosis. What is the most likely mechanism of the acid/base disturbance in this patient?