Name the pulmonary imbalance using the following Arterial blood Gas (ABG) values: pH 7.41, PaCO2 46, HCO3- 30

Choice A reason: Beta blockers decrease renin release, reducing angiotensin II and aldosterone, which lowers blood pressure. This statement is accurate, reflecting correct understanding, so it does not indicate a need for further teaching.

Choice B reason: Beta blockers do not primarily decrease peripheral vascular resistance; they reduce heart rate and contractility. Peripheral resistance is more affected by alpha blockers or vasodilators, so this incorrect statement indicates a need for further teaching.

Choice C reason: Beta blockers reduce heart rate and myocardial contractility, decreasing cardiac output and blood pressure. This statement is correct, showing proper understanding, so it does not require additional teaching.

Choice D reason: While beta blockers do not directly block angiotensin II, they reduce its production by decreasing renin. The statement is imprecise but not entirely wrong, making it less indicative of a teaching need than choice B.

Choice A reason: Metabolic acidosis involves low pH (<7.35) and low HCO3- (<22 mEq/L). Here, pH is 7.48 (alkalotic) and HCO3- is 29 mEq/L (high), indicating alkalosis, not acidosis. PaCO2 (44 mm Hg) is normal, ruling out respiratory causes, making this choice incorrect.

Choice B reason: pH 7.48 (high), PaCO2 44 mm Hg (normal), and HCO3- 29 mEq/L (high) indicate metabolic alkalosis, likely from conditions like vomiting or diuretic use, increasing bicarbonate. No respiratory compensation (normal PaCO2) confirms uncompensated metabolic alkalosis, making this the correct choice.

Choice C reason: Respiratory acidosis requires high PaCO2 (>45 mm Hg) and low pH. Here, PaCO2 is 44 mm Hg (normal) and pH is 7.48 (alkalotic), with high HCO3-, pointing to a metabolic cause, not respiratory, making this choice incorrect for the ABG values.

Choice D reason: Respiratory alkalosis involves low PaCO2 (<35 mm Hg) and high pH. With PaCO2 at 44 mm Hg (normal) and high HCO3- (29 mEq/L), the alkalosis is metabolic, not respiratory. This choice doesn’t match the ABG profile, making it incorrect.