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: This is incorrect because bradypnea is a term for slow breathing, usually less than 12 breaths per minute. The client is breathing rapidly, not slowly.

Choice B reason: This is correct because Kussmaul's respirations are a type of breathing pattern that is deep, regular, and rapid, usually more than 20 breaths per minute. Kussmaul's respirations are a sign of metabolic acidosis, which occurs in diabetic ketoacidosis due to the accumulation of ketones in the blood. The client is trying to exhale the excess carbon dioxide and lower the acidity of the blood.

Choice C reason: This is incorrect because Cheyne-Stokes respirations are a type of breathing pattern that is irregular, with periods of apnea (no breathing) alternating with periods of rapid breathing. Cheyne-Stokes respirations are a sign of cerebral dysfunction, such as stroke, brain injury, or coma.

Choice D reason: This is incorrect because Biot's respirations are a type of breathing pattern that is irregular, with periods of apnea (no breathing) interspersed with periods of normal breathing. Biot's respirations are a sign of brainstem damage, such as meningitis, encephalitis, or head trauma.

Choice A reason: Kidney function is not indicated by the PaCO2 level, but rather by the creatinine and blood urea nitrogen (BUN) levels. The kidneys are responsible for regulating the HCO3- level, which is the other component of the carbonic acid-bicarbonate buffer system.

Choice B reason: Bicarbonate buffers are not indicated by the PaCO2 level, but rather by the HCO3- level. Bicarbonate buffers are substances that can accept or donate hydrogen ions to maintain the pH of the blood. They are part of the carbonic acid-bicarbonate buffer system, which is the main buffer system in the body.

Choice C reason: Phosphate buffers are not indicated by the PaCO2 level, but rather by the PO4^3^- level. Phosphate buffers are substances that can accept or donate hydrogen ions to maintain the pH of the intracellular fluid and the urine. They are part of the phosphoric acid-phosphate buffer system, which is the second most important buffer system in the body.

Choice D reason: Lung ventilation is indicated by the PaCO2 level, which is the partial pressure of carbon dioxide in the blood. Lung ventilation is the process of moving air in and out of the lungs, which affects the amount of carbon dioxide exhaled. The lungs are responsible for regulating the PaCO2 level, which is the other component of the carbonic acid-bicarbonate buffer system.