NRNP 6566 WEEK 3 KNOWLEDGE CHECK

NRNP 6566 WEEK 3 KNOWLEDGE CHECK • Question 1 Mrs. Franklin is a 68-year-old woman with long-standing, persistent AF being managed with rhythm control on dofetilide. She also has type 2 diabetes mellitus (T2DM), hypertension, and a myocardial infarction 3 years ago. What is her CHADS2 and CHA2DS2-VASc score? How would you interpret those scores in deciding on treatment for Mrs. Franklin? Correct Answer: CHADS2 score=2 (HTN, T2DM) A score of greater than 2 is considered high risk for stroke. CHA2DS2-VASc score=5 (age 65, female, HTN, T2DM, coronary artery disease [CAD]) A score of greater than 2 is considered high risk for stroke. Many patients are hesitant to begin anticoagulation due to the expense and inconvenience. However, after understanding that a 4% annual risk for stroke (if the CHA2DS2-VASc Score is 4) equates to 40% risk over 10 years, patients are more willing to comply. • Question 2 A 58-year-old male complains of a galloping heart rate and shortness of breath. Vital signs are BP 110/74, P 156, RR 22 Oxygen sat is 96%. Continuous EKG monitoring identifies periods of sinus tachycardia as well as episodes of atrial fibrillation. Laboratory results for this patient show: Hemoglobin 13.3 g/dl Hematocrit 39% WBC 8.7 Platelets 172,000 Sodium 140 Potassium 3.7 TSH 0.0 mIU/L T4 3 mg/dl T3 6.6 pg/ml What is your working diagnosis and what two initial medications would you prescribe for this patient? Correct Answer: The low TSH combined with the high T4 and T3 are indicative of hyperthyroidism. A common side effect of the hypermetabolic state is atrial fibrillation. Two medications that should be considered for initial treatment are beta blockers and anti-thyroid drugs. Beta blockers offer quick relief symptoms of hyperthyroidism, such as tachycardia, palpitations, heat intolerance, and nervousness. Nonselective beta blockers, such as propranolol, are preferred because they have a more direct effect on hypermetabolism. Start propranolol at 10 to 20 mg every 6 hours and titrate upward until symptoms are controlled. Once the T4 and T3 have normalized, the propranolol can be tapered off. Methimazole is the drug of choice in nonpregnant patients because of its lower cost, longer half-life, and lower incidence of hematologic side effects. Start the medication at 15 to 30 mg per day. Monthly free T4 and T3 levels should be obtained and methimazole adjusted to reach an euthyroid state. Maintenance doses may be lower (5–10 mg daily). • Question 3 A 63-year-old female has been successfully cardioverted and is now on amiodarone for rhythm maintenance. The patient is on the following medications: Warfarin 10 mg po daily Lisinopril 20 mg po daily Amiodarone 400 mg po daily Prilosec 20 mg po daily Digoxin 4250 mcg po daily What interactions are possible and how would you monitor and adjust for them. Correct Answer: Amiodarone is known to interact with warfarin and digoxin. Digoxin levels may increase 30–50% when taken with amiodarone. Amiodarone increases digoxin concentrations by inhibiting the P-glycoprotein (P-gp) mediated transport that facilitates the elimination of digoxin from the body. The greater the concentration of amiodarone the greater the increase in serum digoxin levels. Patient’s digoxin levels should be closely monitored, and dosing should be decreased to account for this effect. Amiodarone is a potent inhibitor of the enzymes that metabolize warfarin. Decreased metabolism of warfarin leads to higher plasma concentration levels and increased risk of bleeding. Warfarin doses should be decreased, and frequent INR monitoring is indicated when initiating amiodarone treatment.