Fundamentals of Nursing Q 79
A client is brought to the emergency department and states that he has accidentally been taking two times his prescribed dose of Warfarin (Coumadin). After observing that the client has no evidence of any obvious bleeding, the nurse should do which of the following?
A. Draw a sample for activated partial thromboplastin time (aPTT) level.
B. Draw a sample for prothrombin time (PT) level and international normalized ratio (INR).
C. Prepare to administer Vitamin K.
D. Prepare to administer Protamine sulfate.
Correct Answer: B. Draw a sample for prothrombin time (PT) level and international normalized ratio (INR).
The next action for the nurse to take is to draw a sample for INR and PT level to check the client’s anticoagulation status and risk for bleeding. These results will provide information on how to manage the client by either giving an antidote such as Vitamin K or administering a blood transfusion. Specific evaluation of warfarin toxicity should involve evaluation of the patient’s PT, INR, CBC, and BMP with hepatic function, in addition to the standard co-ingestions and a focused evaluation surrounding their symptoms.
Option A: The aPTT determines the effects of heparin therapy. It is recommended that patients undergo measurement of PT/INR and PTT during the initial presentation. For acute exposures, patients should receive serial INR assessments every 12-24 hours. If INR remains normalized at 36 hours and there are no signs of bleeding, no further testing is generally necessary.
Option C: The results of the INR and PT level will be needed first. For these recommendations, coagulopathy is defined as INR > 1.4. Warfarin toxicity is defined as INR > 3.0 or >3.5 in a patient with a mechanical heart valve. Unintentional toxicity in patients who are treated with warfarin for an underlying condition (most common presentation).
Option D: Protamine sulfate is the antidote for heparin overdose. Patients with elevated INR displaying evidence of coagulopathy during evaluation, do not need to be started on vitamin K unless the INR is greater than 10 or they have evidence of bleeding.