A nurse is caring for a client who has a pulmonary embolism and has been on a heparin continuous infusion for 5 days. The provider prescribes warfarin PO without discontinuing the heparin. The client asks the nurse why both anticoagulants are necessary. Which of the following statements should the nurse make?

Choice A reason:Testing the drainage for the halo sign is the first action the nurse should take, as clear drainage from the nose following a basal skull fracture could indicate a cerebrospinal fluid (CSF) leak, which contains glucose.

Choice B reason:Asking the client to blow his nose could potentially increase the risk of infection or worsen a CSF leak and is not recommended as a first action.

Choice C reason:While notifying the physician is important, it should be done after confirming whether the drainage is CSF, which would require immediate medical intervention.

Choice D reason:Suctioning the nostril is not the first action to take, as it could potentially disrupt the site of the leak and is not diagnostic of a CSF leak.

Choice A: Troponin Troponin levels increase within 3-12 hours from the onset of chest pain, peak at 24-48 hours, and return to baseline over 5-14 days. Troponin is a protein found in cardiac muscle fibers that regulates muscular contraction. When heart muscle is damaged, as in the case of an MI, troponin is released into the bloodstream. The elevation of troponin levels is a key indicator of myocardial infarction and can be used to diagnose and assess the extent of heart muscle damage. Troponin is the most reliable laboratory value that is expected to be elevated following a myocardial infarction, making it the correct choice in this scenario.

Choice B: Aspartate aminotransferase (AST) AST is an enzyme found in high concentrations in the liver, heart, muscles, kidneys, and brain. It is released into the bloodstream when any of these tissues are damaged. While AST can be elevated in cases of MI, it is not as specific as troponin because it is present in many other tissues besides the heart.

Choice C: Serum amylase Serum amylase is an enzyme that helps digest carbohydrates and is primarily associated with the pancreas and salivary glands. Its elevation is not specifically related to myocardial infarction but can be seen in other conditions such as pancreatitis.

Choice D: Unconjugated bilirubin Unconjugated bilirubin is a breakdown product of hemoglobin from red blood cells. Elevated levels of unconjugated bilirubin are typically associated with conditions affecting the liver or the breakdown of red blood cells, not myocardial infarction.