Why does administering a selective COX-2 inhibitor after cardiac surgery increase the risk of delayed sternal closure?

💡 Explanation

After cardiac surgery, bone remodeling is essential for sternal healing. Inhibiting COX-2 reduces prostaglandin E2 (PGE2) synthesis, because PGE2 stimulates osteoblast activity and bone formation; therefore, impaired PGE2 synthesis slows bone remodeling and increases the risk of delayed sternal closure rather than promoting coagulation or altering platelet aggregation through thromboxane or prostacyclin.

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