Final answer:
The nurse should administer the ordered dose of warfarin as the patient's INR of 2.7 is within the therapeutic range. Pharmacogenomics could help tailor warfarin dosing more precisely based on individual genetic factors, improving safety and efficacy.
Step-by-step explanation:
In the context of a patient with atrial fibrillation receiving warfarin (Coumadin), an INR value of 2.7 indicates that the patient's blood clotting is within the therapeutic range for this condition (usually between 2.0 and 3.0). Given that the INR is appropriately managed, the nurse should administer the dose as ordered, which is option (a). However, it is still important to carry out routine monitoring as warfarin dosing can be quite complex and individualized, potentially influenced by factors such as liver function and genetic variations that affect drug metabolism.
Pharmacogenomics could play a role in this scenario by examining the patient's genetic makeup to predict how they will respond to warfarin. Since the liver produces coagulation factors and is involved in the metabolism of warfarin, genetic differences in enzymes crucial for liver function can significantly affect the effectiveness and safety of the medication. Through pharmacogenomics, a more personalized and precise dosage can be determined to avoid over- or under-anticoagulation, thereby mitigating the risk of adverse effects such as bleeding or thrombosis.
It's important to note that administration of vitamin K would be a countermeasure if the INR were dangerously high, indicating a risk for bleeding complications, not when it is within the therapeutic range as in this scenario. Adjustments in the dose of warfarin or switching to alternative anticoagulation therapies like dabigatran (Pradaxa), rivaroxaban (Xarelto), or low molecular weight heparins would depend on regular INR monitoring and physician assessment.