A nurse is assessing a client who is postoperative following a coronary artery bypass graft surgery. The nurse should identify that which of the following findings is an early indication of cardiac tamponade?

A. Aspirin: Aspirin is a nonsteroidal anti-inflammatory drug (NSAID) that can irritate the gastric mucosa and increase the risk of gastrointestinal bleeding. It is contraindicated in clients with a history of peptic ulcer disease.

B. Ketorolac: Ketorolac is a very potent Non-Steroidal Anti-Inflammatory Drug (NSAID) usually given IV or IM. It carries a high risk of GI ulceration and perforation and is contraindicated in clients with active PUD or a high risk of GI bleeding.

C. Acetaminophen: Acetaminophen provides analgesic and antipyretic effects without significant gastrointestinal irritation. It is safe for clients with peptic ulcer disease, making it the preferred choice for headache management in this context.

D. Ibuprofen: Ibuprofen, like other NSAIDs, can exacerbate peptic ulcer disease by inhibiting prostaglandin synthesis and increasing the risk of GI bleeding, so it should be avoided in clients with a history of ulcers.

Rationale for correct choices

• Stop the magnesium sulfate infusion: The client exhibits signs of magnesium sulfate toxicity, including lethargy, shallow respirations, hyporeflexia (DTR 1+), and oliguria (urine output 20 mL/hr). Immediate cessation of the infusion is the priority to prevent progression to respiratory depression, coma, or cardiac arrest. Stopping the infusion reduces further magnesium accumulation and stabilizes the client.

• Calcium gluconate: Calcium gluconate is the antidote for magnesium sulfate toxicity. It counteracts the neuromuscular and cardiac effects of magnesium, reversing hyporeflexia and respiratory depression. The nurse should prepare calcium gluconate IV for rapid administration while monitoring vital signs and respiratory status closely.

Rationale for incorrect choices

• Apply oxygen via nasal cannula: Although supplemental oxygen can support the client’s respiratory function, it does not reverse the toxic effects of magnesium. Oxygen therapy alone is insufficient in managing magnesium toxicity and is secondary to stopping the infusion.

• Place the client in Trendelenburg position: Trendelenburg positioning is not indicated and may worsen respiratory compromise. Maintaining a side-lying or semi-Fowler’s position is safer for airway management and monitoring during magnesium toxicity.

• Magnesium sulfate: Continuing magnesium sulfate would worsen toxicity, potentially leading to respiratory failure, cardiac arrest, and further CNS depression. Administration is contraindicated once toxicity signs appear.

• IV antibiotics: There is no indication of infection or sepsis in the client’s current assessment. Antibiotics do not address magnesium toxicity and are not warranted at this stage.