Lena Mason, who has diabetes, is admitted in a stuporous condition. Her blood gases show a pH of 7.33, PaCO2 of 40 mm Hg, and HCO3- of 20 mEq/L. What type of acid-base imbalance does this patient have?

Choice A reason: Producing phosphate buffers is not the main function of the kidneys in response to acid-base disturbances. Phosphate buffers are mainly found in the intracellular fluid and the urine, where they help to maintain the pH by binding or releasing hydrogen ions.

Choice B reason: Adjusting PaCO2 levels is not the function of the kidneys, but rather the function of the lungs in response to acid-base disturbances. The lungs regulate the PaCO2 levels by increasing or decreasing the rate and depth of respiration, which affects the amount of carbon dioxide exhaled.

Choice C reason: Producing protein buffers is not the function of the kidneys, but rather the function of the cells and the plasma in response to acid-base disturbances. Protein buffers are the most abundant and versatile buffers in the body, as they can act as acids or bases by donating or accepting hydrogen ions.

Choice D reason: Excreting or reabsorbing hydrogen or bicarbonate is the main function of the kidneys in response to acid-base disturbances. The kidneys regulate the HCO3- levels by either reabsorbing it from the filtrate or generating it from carbon dioxide and water. The kidneys also regulate the hydrogen ion levels by either excreting it into the urine or exchanging it for sodium ions.

Choice A reason: This is correct because acidosis is a condition where the serum pH is lower than the normal range of 7.35 to 7.45. Acidosis can be caused by an excess of acids or a loss of bases in the body, which can affect the function of various organs and systems.

Choice B reason: This is incorrect because equal bicarbonate is not a condition, but a term that describes the balance between bicarbonate (HCO3-) and carbonic acid (H2CO3) in the blood. Bicarbonate is a base that buffers the acids in the blood and maintains the pH. Equal bicarbonate means that the ratio of bicarbonate to carbonic acid is 20:1, which is the normal value.

Choice C reason: This is incorrect because neutral carbonic acid is not a condition, but a term that describes the pH of carbonic acid (H2CO3) in the blood. Carbonic acid is an acid that forms when carbon dioxide (CO2) dissolves in water. Neutral carbonic acid means that the pH of carbonic acid is 7.0, which is neither acidic nor basic.

Choice D reason: This is incorrect because alkalosis is a condition where the serum pH is higher than the normal range of 7.35 to 7.45. Alkalosis can be caused by a loss of acids or an excess of bases in the body, which can affect the function of various organs and systems.