Coagulation Relative Treatment Conditions for Hepatobiliary Disorders

Vitamin K

0.5–1 mg/kg, SC

Initial dosing q 12 h, 3 times, then weekly

Vitamin K administered to all jaundiced animals due to suspected hepatobiliary disease; dose at initial presentation to avoid procedural delays because of bleeding risks, especially in cats. Avoid IV: may cause anaphylactoid reaction. Excess administration (ie, daily) in cats can cause Heinz body hemolysis.

Desmopressin

0.3–1 mcg/kg, SC or IV

Effect onset 30 min to 8 h, one time

Mobilizes preformed large VWF monomers from endothelial stores; repeated dosing thus has decreased to no effects within 6 h. Desmopressin provokes water retention with potential to worsen ascites, but intermittent single-use dose does not pose this hazard.

Fibrinolytic

Epsilon-aminocaproic acid

50–100 mg/kg, IV

15 mg/kg, PO

At least 1 h

q 8 h

Demonstrated to be well tolerated, with rare GI upset. Rapid IV dosing may cause bradycardia and hypotension. No evidence that it generates a hypercoagulable status, although it has potential to exacerbate or slow recanalization of preexisting thrombi. Treatment response best monitored with thromboelastography.

Anticoagulants/antithrombotics

Platelet inhibition

Clopidogrel

1.1–3 mg/kg, PO (dogs)

18.85 mg, PO (cats)

q 24 h (dogs & cats)

A single oral loading dose (eg, 4–10 mg/kg for dogs; 37.5 mg total dose for cats) may accelerate achievement of therapeutic plasma concentrations. Use of NSAIDs to suppress platelet aggregation is not recommended for patients with liver disease.

Indirect inhibition of FXa:

Low–molecular weight heparins (indirect inhibitor via AT of FXa, thrombin & other factors)

Enoxaparin

0.8 mg/kg, SC (dog)

0.75–1 mg/kg, SC (cat)

q 6–8 h (dog)

q 6–12 h (cat)

Specific monitoring for anti-FXa activity improves therapeutic dosing.¹

Dalteparin

100–175 U/kg, SC (dog)

75 U/kg, SC (cat)

q 8 h (dog)

q 6–8 h (cat)

Specific monitoring for anti-FXa activity improves therapeutic dosing.^a

Direct FXa inhibitor

Rivaroxaban

0.5–2 mg/kg, PO (dog)

0.5–1 mg/kg, PO (cats)

q 24 h (dogs & cats)

Dosing for healthy dogs effective at 2 mg/kg; animals ill with liver disease may require decreased dose. Monitoring should tailor dose. PT clotting time shown to have good correlation with drug-specific assessment method. Establish patient baseline for comparison. Feeding and use of gastroprotectants did not affect bioavailability.