Page 166 - Cardiac Nursing

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142 PA R T II / Physiologic and Pathologic Responses

Table 6-4 ■ AGENTS USED TO PROMOTE COAGULATION BLOOD PRODUCTS
Product Standard Volume Administration Factor Replaced
Platelets (random donor) Usually 8–10 donors/unit at 50–70 mL/unit Rapid administration increases possible
allergic reaction
Platelets (single donor) One donor/200–300 mL Rapid administration possible allergic reaction
Packed red blood cells (RBC) 250–350 mL/unit Rapid administration; blood type mismatch
Fresh frozen plasma (FFP) 200–250 mL/unit Rapid administration II, V, VII, IX, X, XI, XII
Cryoprecipitate Usually 8–10 donors/unit at 10–20 mL/unit Rapid administration increases possible I
allergic reaction

th
Modified from Dzieczkowski J & Anderson K (2005) in Transfusion biology and therapy in Harrison’s principles of internal medicine (16 ed.). New York: McGraw-Hill Medical
Publishing Division.

implemented because ecchymotic areas under the cuff can de- the number of various blood products received. RBC loss needs to
velop. Hemodynamic monitoring may be used and variations in be replaced, but it is important to realize that a transfusion is not
indices may indicate cardiac failure, hypovolemia, or pulmonary a benign intervention. Critically ill patients may be at risk for im-
complications such as PE. Monitoring urine output for at least munosuppressive and microcirculatory complications with red
0.5 to 1 mL/kg per hour should be routine practice. Removal of cell transfusions. 13 A restrictive transfusion strategy (transfuse
large catheters used for percutaneous interventions should al- for a hemoglobin 7.0 g/dL) has been shown to be as effective
ways be performed with care. Achieving and maintaining hemo- as a liberal strategy (transfuse for a hemoglobin 10 g/dL) with
stasis is dependent on technique. Manual pressure should be ap- a decrease in mortality. 13 The only two groups of patients that
plied slightly above the insertion site of the vessel and minimal may require the more liberal transfusion strategy are patients
padding should be used to control bleeding. This technique will with an acute myocardial infarction or unstable angina. 13 In
allow visualization of the site for continual monitoring and cases of massive bleeding that is not responsive to the usual in-
lessen the chance of hematoma formation. Once adequate he- terventions as described above, recombinant factor VIIa has
mostasis is achieved, other devices can be applied to assure ade- been used as an additional intervention. Originally used for
quate clot formation at the puncture site. Proper technique in treatment of hemophilia, off-label use of factor VIIa has in-
hemostasis control is especially important for patients with a creased markedly over the last 10 years. Recombinant factor
coagulopathy. VIIa binds to the surface of activated platelets and promotes
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If hemorrhage is present, the priority should be volume resusci- thrombin formation thereby enhancing clot formation. Dosing
tation. Blood products should be replaced depending on estimated of this drug for off-label use varies greatly depending on the set-
blood loss and laboratory values. Aggressive fluid resuscitation ting (surgery, trauma, hemorrhagic stroke, reversal of oral coag-
should be performed through short, large-bore venous access us- ulation therapy, or impaired hepatic function). 14 Caution
ing pressure bags if the patient is hypotensive to assure fast in- should be used when using factor VIIa due to the risk of throm-
travascular volume repletion. While infusing blood products, the boembolic adverse events. 14,15 Observation for bleeding should
nurse should observe for allergic reactions (Tables 6-4 and 6-5). include monitoring of all vascular accesses as well as the area
Continual bleeding may require massive blood product replace- around the site. Vigilant surveys by the nurse of the skin surface
ment, which can cause a “washout” effect of most of the func- and digits are necessary to observe for petechiae, ecchymosis,
tioning coagulation proteins, and paradoxically cause further and other skin disruptions that may provide early warning signs
coagulopathy. It is also important to keep accurate records as to of impending DIC (Display 6-3).

Table 6-5 ■ DRUGS USED TO PROMOTE COAGULATION
Drug Dose Side Effects Mechanism
Protamine 1 mg for every 100 u of IV heparin Hypotension; possible anaphylaxis Binds heparin to neutralize
if exposed to NPH anticoagulant effect
Desarginine vasopressin 0.3 g/kg IV at 12- to 24-h interval Mild flushing, headache, mild-to- Temporarily improves platelet function
(DDAVP) moderate abdominal pain in patient with renal or liver disease;
mechanism not clear
Recombinant activated Dose varies depending on indication; Thrombotic events Binds to surface of activated Platelets and
Human factor VII (rFVIIa) most current use is off-label dose can promotes Factor X activation and
(Novo-Seven)* range from 5 to 300
mcg/kg in thrombin generation where platelets
varying number of doses are localized at a site of injury

*Goodnough, L., & Shander, A. (2007). Recombinant factor VIIa: Safety and efficacy. Current Opinion in Hematology, 14, 504–509.
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Brunton, L., Lazo, J., & Parker, K. (2006). Goodman and Gilman’s the pharmacological basis of therapeutics. New York: McGraw-Hill Company.