Exam 3 - Blood Disorders Flashcards
What are the S/S of vWF disorder?
- Easy bruising
- Epistaxis
- Menorrhagia
What would lab values be for someone with vWF deficiency?
- Normal PT & aPTT
- Bleeding time is prolonged
What are the treatments for vWF deficiency?
- Desmopressin
- Cryoprecipitate
- Factor VIII
How does DDAVP work in regards to treatment of von Willebrand deficiency??
Stimulates vWF release from endothelial cells; synthetic analouge of vasopressin
What is the dose for DDAVP?
0.3 mcg/kg in 50 mL over 15-20 mins (Do not bolus)
What is the onset & duration of DDAVP?
- Onset: 30 mins
- Duration: 6-8 hrs
What are side effects of DDAVP?
- HA
- Stupor
- Hypotension
- Tachycardia
- Hyponatremia
- Water intoxication (excessive water retention)
What is the most major side effect of DDAVP?
Hyponatremia
From dilution
Someone that gets DDAVP needs to be on what?
Fluid restriction 4-6hrs before & after DDAVP
Causes thirst which can lead to water intoxication and hyponatremia
At what serum Na+ do you see confusion, restlessness, and widening of QRS?
120 mEq/L
What CNS and EKG changes are seen at a serum Na+ of 115 mEq/L?
- CNS: Somnolence and nausea
- EKG: Elevated ST, widened QRS
What serum Na+ can seizures, coma, and Vtach/Vfib be seen?
110 mEq/L
What blood product can be utilized for vWF disease if the patient is unresponsive to DDAVP?
What is its risk?
- Cryoprecipitate
- Infection risk, not submitted to viral attenuation
1 unit of Cryo raises the ____ level by ___?
Fibrinogen by 50 mg/dL
What is Factor VIII concentrate made of?
- Pool of plasma from a large number of donors
- Contains factor VIII and vWF
When is Factor VIII given?
Preop or intraop
When should DDAVP be given prior to surgery?
30-60mins before Sx
Pts with coagulopathies undergoing neuraxial anesthesia are at increased risk for what?
- Hematoma
- Nerve compression
What are the anesthesia considerations for someone with vWF deficiency?
- Avoid trauma (particularly airway)
- Avoid IM sticks
- Avoid arterial lines (if feasible)
- Avoid spinals
How does heparin work?
- Thrombin inhibition
- Antithrombin III activation
ATIII inhibits thromin and factors IX and X
What labs are monitored with heparin?
PTT and ACT (activated clotting time)
What is the mechanism of action of Coumadin?
Inhibition of vitamin K-dependent factors (II, VII, IX, X)
What is the onset for Vitamin K administration?
6-8hrs
What drugs/products can be given to reverse coumadin faster than Vit K?
- Prothrombin complex concentrates
- Factor VIIa
- FFP
What is the mechanism of action for fibrinolytics (UK, streptokinase & tPA)?
Convert plasminogen to plasmin, which cleaves fibrin
How do tranexamic acid (TXA) and aminocaproic acid work?
Inhibit conversion of plasminogen to plasmin
Treatment for antiplatelet reversal?
- D/C drugs on time
- Platelet transfusion
Some causes of DIC?
- Trauma
- Amniotic fluid embolus
- Malignancy
- Sepsis
- Incompatible blood transfusions
Patho of DIC?
What will labs show for someone in DIC?
- ↓Platelet count
- Prolonged PT, PTT & TT (thrombin time).
- ↑ fibrin degradation products
What is the best way to treat DIC?
Other treatments?
- Treat the underlying cause
- Blood component transfusions
When is antifibrinolytic therapy given to someone in DIC?
Trick question, it shouldn’t. Can lead to catastrophic thrombotic complications
What is Factor V Leiden deficiency?
- Genetic mutation of factor V that is resistant to activated protein C
- Leads to factor V leiden making excess fibrin
Activated Protein C usually inhinits favtor V activity
What the symptom for TXA toxicity?
Loss of color vision
What does Activated Protein C do?
Inactivates factor V when enough fibrin has been made.
Who is usually tested for Factor V Leiden?
Pregnant women. Especially ones with unexplained late stage abortions and DVT
What anticoagulant medications could someone with Factor V Leiden be put on?
Why is this good for pregnant woemen?
- Warfarin
- LMWH & unfractionated heparin
- Prevents placental thrombosis and leads to better outcomes
What is the hallmark sign of HIT?
Plt count < 100,000, usually 5-14 days after initial therapy
thrombocytopenia
HIT results in ____ activation and potential ____ ?
platelet; thrombosis
What causes HIT?
- Creation of immune complexes (IgG antibody, platelet factor 4, and heparin)
What is heparin replaced with when HIT is diagnosed?
Argatroban, lepirudin, bivalirudin (direct-thrombin inhibitors)
What is Fondaparinux & when is it used?
- A synthetic Factor Xa inhibitor
- Used to treat VTE in HIT
When do HIT immune complexes clear from the circulation?
Typically, within 3 months - should still avoid future heparin exposure
