A client with heart failure is taking an angiotensin-converting enzyme inhibitor (ACE-I) and reports a nagging cough. Which replacement medication will the nurse expect to be prescribed for this client?

Choice A reason: A lithium level of 1.2 mEq/L is within the therapeutic range (0.6–1.5 mEq/L) for bipolar disorder. Symptoms like confusion, ataxia, polyuria, and blurred vision indicate toxicity, which occurs at higher levels, typically above 1.5 mEq/L, making this level unlikely for these severe symptoms.

Choice B reason: A lithium level of 1.4 mEq/L is at the upper end of the therapeutic range. While mild side effects may occur, severe symptoms like mental confusion, ataxia, and polyuria suggest toxicity, which typically occurs at levels above 1.5 mEq/L, ruling out this option.

Choice C reason: A lithium level of 2.3 mEq/L indicates toxicity, causing neurological symptoms (confusion, ataxia), polyuria due to nephrogenic diabetes insipidus, and blurred vision from central nervous system effects. These symptoms align with lithium toxicity, which occurs at levels above 1.5 mEq/L, making this the expected level.

Choice D reason: A lithium level of 1.8 mEq/L is slightly above therapeutic range and may cause mild toxicity symptoms, such as tremor or nausea. However, the severe symptoms described (confusion, ataxia, polyuria) are more consistent with higher toxic levels, such as 2.3 mEq/L, making this less likely.

Choice A reason: Pulmonary edema is associated with left-sided heart failure, where blood backs up into the lungs, causing fluid leakage and crackles. Right-sided heart failure primarily affects systemic venous return, leading to peripheral and abdominal fluid accumulation, not pulmonary edema, making this inconsistent with the diagnosis.

Choice B reason: Dependent edema, such as ankle or leg swelling, occurs in right-sided heart failure due to impaired right ventricular pumping, causing blood to back up in systemic veins. This leads to fluid leakage into peripheral tissues, a hallmark symptom consistent with right-sided heart failure.

Choice C reason: Abdominal swelling, or ascites, results from right-sided heart failure due to increased venous pressure in the systemic circulation, causing fluid accumulation in the peritoneal cavity. This is a common and consistent finding, reflecting the systemic congestion caused by right heart dysfunction.

Choice D reason: Dry cough is typically associated with left-sided heart failure due to pulmonary edema irritating the airways. Right-sided heart failure causes systemic venous congestion, not pulmonary fluid buildup, so dry cough is not a primary or consistent symptom of this condition.

Choice E reason: Distended neck veins (jugular vein distension) occur in right-sided heart failure due to increased systemic venous pressure from impaired right ventricular emptying. This is a key clinical sign, reflecting the backup of blood in the venous system, consistent with right-sided heart failure.