A nurse is caring for a client who is receiving warfarin (Coumadin) therapy to prevent a deep vein thrombosis.
Which of the following medications should the nurse have available in the event of an overdose?

Choice A rationale

Protamine sulfate is the specific antidote for heparin overdose. It is a highly basic (alkaline) protein that forms a stable, inactive complex with the highly acidic heparin molecule, thereby neutralizing its anticoagulant effect, primarily its inhibition of Factor Xa and thrombin. The rapid action of protamine sulfate makes it crucial for reversing life-threatening bleeding associated with excessive heparin administration.

Choice B rationale

Vitamin K (phytonadione) is the antidote for warfarin overdose because it promotes the synthesis of active Vitamin K-dependent clotting factors (II, VII, IX, X) in the liver, reversing warfarin's inhibitory action. It is ineffective against heparin, which acts on existing clotting factors and antithrombin.

Choice C rationale

Glucagon is a pancreatic hormone used to treat severe hypoglycemia by stimulating hepatic glycogenolysis and gluconeogenesis, increasing blood glucose levels. It has no chemical or pharmacological effect on reversing the anticoagulant properties of heparin.

Choice D rationale

Ferrous sulfate is an oral iron supplement used to treat iron deficiency anemia by providing elemental iron necessary for hemoglobin synthesis in red blood cells. It does not interact with or neutralize heparin's anti-clotting mechanism.

Choice A rationale

An elevated Hct (normal ≈ 36%-50%), elevated BUN (normal 8-20 mg/dL), and high urine specific gravity (normal 1.005-1.030) are all indicative of volume depletion or dehydration. Monitoring intake and output precisely quantifies the fluid balance, which is crucial for determining the degree of deficit and evaluating the effectiveness of rehydration therapy.

Choice B rationale

The client's confusion and weakness are potential symptoms of dehydration, as reduced intravascular volume can impair cerebral perfusion and electrolyte imbalances can disrupt nerve and muscle function. Regularly checking orientation provides an essential ongoing assessment of the client's neurological status and the effectiveness of fluid replacement.

Choice C rationale

The client's lab values and symptoms strongly suggest dehydration, which requires increased fluid intake, not restriction. Fluid restriction would exacerbate the existing hypovolemia, further worsening the elevated Hct, BUN, and specific gravity, potentially leading to renal compromise and worsening confusion.

Choice D rationale

Dehydration often leads to orthostatic hypotension due to reduced circulating blood volume. Instructing the client to sit briefly before standing allows time for baroreceptor reflexes to compensate for the positional change, preventing a sudden drop in blood pressure and minimizing the risk of a fall.

Choice E rationale

Daily weights provide a highly sensitive and objective measure of fluid status changes. A rapid change in body weight, especially in the context of dehydration and hypovolemia, directly reflects the magnitude of fluid loss or gain, making it a critical parameter for monitoring the effectiveness of interventions.