M.Sc Nursing Fluid, Electrolyte, and Acid-Base Balance — practice questions — page 2

1. Blood pH must stay within a very narrow physiological range for proper enzyme and protein function. 2. This range is fixed and very narrow. 3. That range is 7.35 to 7.45. 4. Values below 7.35 indicate acidosis and above 7.45 indicate alkalosis, so the other ranges are incorrect. _Source: OpenStax Anatomy and Physiology (CC BY 4.0), Ch 26 "Fluid, Electrolyte, and Acid-Base Balance", p.1270 §Disorders of Acid-Base Balance_

1. In ketoacidosis, fat breakdown produces ketone bodies including acetoacetic acid, beta-hydroxybutyric acid, and acetone. 2. One of these ketone bodies is volatile and can be exhaled through the lungs. 3. The classic fruity breath odor specifically to exhaled acetone. 4. Lactic acid and ammonia are not described as producing this smell, so they are ruled out. 5. So acetone is correct. _Source: OpenStax Anatomy and Physiology (CC BY 4.0), Ch 26 "Fluid, Electrolyte, and Acid-Base Balance", p.1268-1269 §Acid-Base Balance: Ketoacidosis_

1. Metabolic alkalosis is a condition of excess blood bicarbonate. 2. Cushing's disease is caused by chronic hypersecretion, not hyposecretion, of ACTH from the anterior pituitary. 3. Excess ACTH raises aldosterone levels. 4. Elevated aldosterone increases potassium loss through urinary excretion, contributing to the alkalosis. 5. Diarrhea-related bicarbonate loss is listed elsewhere as a cause of metabolic acidosis, the opposite condition, so it is ruled out here. 6. So chronic ACTH hypersecretion elevating aldosterone is the correct mechanism. _Source: OpenStax Anatomy and Physiology (CC BY 4.0), Ch 26 "Fluid, Electrolyte, and Acid-Base Balance", p.1271 §Metabolic Alkalosis: Primary Bicarbonate Excess_