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Chapter 20

Case Study

1.
c. The PTT is 75 seconds. Per the protocol, any PTT between 71 and 90 seconds will require a decrease in the heparin rate by 2 units/kg/hour.
2.
b. One of the advantages of LMWH is the longer duration of action, which means that once-daily injections, instead of continuous infusion, are effective.

Review Questions

1.
a. Heparin can be monitored by using the partial thromboplastin time or anti-factor Xa level, depending on the institutional protocol.
2.
a. Protamine is a protein that works to neutralize heparin.
3.
c. The antibodies decrease the platelet count, leaving the client at risk for the development of thrombosis.
4.
b. Alteplase is a thrombolytic drug used to dissolve clots.
5.
d. Heparin is an anticoagulant. It will prevent further clot formation while the body naturally breaks down the clot, but it will not directly dissolve the clot.
6.
d. Clients taking warfarin must maintain a consistent amount of vitamin K in their diet.
7.
b. Warfarin is monitored using the INR, or international normalized ratio.
8.
b. Heparin-induced thrombocytopenia is characterized by a decreased platelet count. Contrary to typical thrombocytopenia, the client is extremely hypercoagulable and often has a thrombosis such as a deep vein thrombosis.
9.
c. This drug is more effectively absorbed when taken with food.
10.
b. Severe uncontrolled hypertension is a contraindication to alteplase administration.
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