A nurse is assessing a female client. Click to highlight the client's findings that are a potential contraindication to the client's new prescription and the nurse should report to the provider. To deselect a finding, click on the finding again. Nurses' Notes: Today, 0830: Client presents to the clinic for the management of hypertension and review of laboratory tests obtained 3 days before this visit. Client has a history of hypertension and asthma. Client is currently taking lisinopril 5 mg PO daily. Today, 0845: Client is alert and oriented to person, place, time, and situation. Respirations are even and non-labored. Scattered wheezes auscultated in bilateral anterior lung fields. Vital signs were obtained. Vital Signs: Today, 0845: Temperature: 37.1° C (98.8° F) Heart rate: 90/min Respiratory rate: 20/min Blood pressure: 158/78 mm Hg Oxygen saturation: 95% Laboratory Results 3 days ago: Hemoglobin: 11 g/dL (12 to 16 g/dL) Hematocrit: 40% (37% to 47%) Sodium: 138 mEq/L (136 to 145 mEq/L) Potassium: 5.6 mEq/L (3.5 to 5 mEq/L) BUN: 30 mg/dL (10 to 20 mg/dL) Creatinine: 2 mg/dL (0.5 to 1 mg/dL)

Spironolactone is a potassium-sparing diuretic that functions as an aldosterone antagonist in the distal convoluted tubule and collecting duct. It promotes the excretion of sodium and water while retaining potassium, making it effective for hypertension but dangerous in the presence of renal insufficiency. Significant contraindications include pre-existing hyperkalemia or concurrent use of other medications that inhibit the renin-angiotensin-aldosterone system, as these combinations exponentially increase the risk of lethal cardiac dysrhythmias. Rationale: A. The client is currently taking lisinopril, an ACE inhibitor, which also increases serum potassium by suppressing aldosterone secretion. Combining lisinopril with spironolactone creates a synergistic effect that leads to severe hyperkalemia. This drug-drug interaction is a major clinical concern because both agents reduce the kidneys' ability to excrete potassium. The nurse must report this concurrent therapy to prevent potential cardiac toxicity resulting from excessive potassium accumulation. B. The client's potassium level of 5.6 mEq/L already indicates hyperkalemia, as it exceeds the normal physiological limit of 5.0 mEq/L. Administering spironolactone to a client with an already elevated potassium concentration is strictly contraindicated. Increasing the potassium burden through potassium-sparing effects could lead to peaked T waves, conduction blocks, or asystole. This laboratory finding must be addressed and corrected before any further potassium-retaining medications are administered. C. A BUN (blood urea nitrogen) of 30 mg/dL signifies impaired renal clearance and decreased glomerular filtration. Elevated nitrogenous waste products often indicate that the kidneys are unable to maintain proper electrolyte balance. Since spironolactone relies on renal excretion and affects renal tubular transport, its use in a client with azotemia is highly risky. This finding suggests the client is at an increased risk for metabolic imbalances if the diuretic is initiated. D. A creatinine level of 2 mg/dL is double the upper limit of the normal range, indicating significant renal dysfunction. Spironolactone is generally contraindicated or requires extreme caution in patients with a creatinine clearance that is significantly reduced. Impaired renal function prevents the body from managing the potassium-sparing effects of the drug, leading to a rapid and dangerous rise in serum electrolytes. This objective marker of kidney failure makes the new prescription inappropriate for the client's current clinical status.