4 Mar Blood Disorders (Exam 3) Flashcards
What is von Willebrand disorder?
The most common hereditary bleeding disorder with a strong genetic component.
List three symptoms of von Willebrand disorder.
- Easy bruising
- Recurrent epistaxis
- Prolonged menstrual bleeding
What is the treatment for most cases of von Willebrand disorder?
- DDAVP (0.3mcg/kg in 50mL of NS admin over 15-20min) for type 1 (pt makes factor but not enough around). Its max effect is in 30min and can last for 6-8hrs
- Specific factor concentrates like cryo for high-grade cases that don’t respond to DDAVP.
What should be monitored closely in patients receiving DDAVP?
Sodium levels.
- Water retention can lead to hyponatremia!!
What is the significance of prolonged bleeding time in von Willebrand disorder?
It is a key lab finding since PT and PTT are usually normal.
What is DDAVP?
A synthetic vasopressin used to treat bleeding issues.
What is the starting dose of DDAVP for treating bleeding?
0.3 micrograms per kilogram.
What side effects can occur with DDAVP treatment?
- Headaches
- Hypertension
- Hypotension
What can happen if sodium levels drop too low in patients on DDAVP?
- Headaches
- Mental status changes
- Seizures
- Death
What is the role of hematology consults in managing von Willebrand disorder?
To analyze labs and determine missing factors before surgery.
What are the classifications of von Willebrand factor disorder?
Type 1 (mild), Type 2 (moderate), Type 3 (severe).
What is cryoprecipitate used for?
To raise fibrinogen levels.
- 1 unit raies fibrinogen levels by 50mg/dL
- There is approximately 2500mg of fibrinogen in 1 unit of cryo
What does F VIII concentrate contain?
Is it higher or lower risk for infection when compared to cryo? Why?
- Factor VIII (duh), and vWF
- Lower risk than cryo because it undergoes viral attenuation (cryo does not)
List the acquired bleeding examples (What we do to patients). (4)
- Heparin
- Warfarin
- Fibrinolytic
- Antiplatelets
True or False: Heparin inhibits thrombin and activates antithrombin III.
What labs do you monitor to track heparin’s effect?
True.
- Note: Heparin will not work well in patients who have ATIII deficiency
- PTT and ACT
What factors does Warfarin inhibit?
How do we attempt to revese its effect?
- 2, 7, 9, and 10
- Give Vit K to reverse but understand that it can take 6-8 hours to see an effect.
- For a more rapid reversal, give prothrombin complex, and recombinant VIIa and FFP!
What is the mechanism of action of fibrinolytics (TPA/SK/UK)?
Breaks down fibrin to dissolve clots by converting plasminogen into plasmin.
What is the mechanism of action of anti-fibrinolytics?
- Inhibition of plasminogen into plasmin
- tranexamic acid, ε–aminocaproic acid, and…
aprotinin (TOO EXPENSIVE)
What is a random S/E of TXA (in toxicity)?
What are the correct doses of TXA for adults? Pedi?
Loss of color vision
- 1-2g for adults
- 15-20mg for pedi
What condition is characterized by widespread thrombosis and consumption of clotting factors?
Disseminated Intravascular Coagulation (DIC).
T/F: Antifibrinolytic therapy is indicated in DIC.
False: Antifibrinolytic therapy generally is contraindicated in DIC owing to potential for catastrophic thrombotic complications
What is the treatment for antithrombin III deficiency?
Fresh frozen plasma (FFP) to provide antithrombin III.
What is heparin-induced thrombocytopenia (HIT)?
An autoimmune condition where heparin causes a decrease in platelets.
Fill in the blank: The normal sodium level ranges from _______.
135 to 145.
What should be avoided before taking patients with von Willebrand’s disease to the operating room?
Missing hematology consult.
What is the recommended approach for vascular access in patients with bleeding disorders?
Use ultrasound guidance.
What are the common acquired bleeding sources?
- Heparin
- Lovenox
- Antiplatelet agents
What does the use of protamine achieve?
Reverses heparin effects.
Describe the financial aspect of using DDAVP versus specific factor concentrates.
DDAVP may be more cost-effective in some cases compared to specific factor concentrates.
What is the importance of fluid intake control in patients on DDAVP?
To prevent severe complications like seizures and death.
What is the normal sodium level range?
135 to 145
Sodium levels outside this range can lead to symptoms.
How do patients with chronic hyponatremia typically respond to treatment compared to those with acute changes?
Patients with chronic hyponatremia tend to do a lot better than those with acute changes.
What is the administration method for cryoprecipitate?
Usually provided in 2 to 10 units depending on the facility.
What is the effect of each unit of cryoprecipitate on fibrinogen levels?
Raises fibrinogen levels by about 50 mg/dL.
What is a potential risk when pooling blood products?
Increased risk of reactions and infection.
What does factor eight concentrate contain?
Factor eight and von Willebrand factor.
When is it common to give a preoperative dose of factor eight?
Before surgery and possibly repeated during surgery.
What might indicate complications during surgery related to bleeding?
Surgeon mentions oozing or difficulty accessing/visualizing areas.
What should be ensured before taking a patient to surgery?
Coagulation factors are normalized.
What is the risk of performing a spinal epidural in a patient with coagulopathy?
Risk of epidural hematoma.
What is a significant concern with vascular access in patients with bleeding risks?
Increased risk of trauma during access procedures.
What is an alternative to arterial lines for monitoring in high-risk patients?
Non-invasive cardiac output monitors.
What is a common cause of acquired bleeding in patients?
Heparin and other anticoagulant medications.
What is the mechanism of action for Heparin?
Inhibits thrombin and activates antithrombin III.
What should be monitored in patients receiving systemic heparinization?
PTT draw every eight to twelve hours.
What is the antidote for Coumadin?
Vitamin K.
What is the time frame for vitamin K to reverse Coumadin’s effects?
6 to 8 hours.
What might be used for acute reversal of Coumadin besides vitamin K?
Blood products such as factor seven, FFP, cryoprecipitate, and prothrombin complex concentrates.
What is the primary action of fibrinolytic agents?
Prevent the conversion of plasminogen to plasmin, causing clots to dissolve.
What are common anti-fibrinolytic agents used in practice?
Amicar (ε–aminocaproic acid) and tranexamic acid (TXA).
What is a key distinction between TXA and fibrinolytic agents?
TXA does not break down clots; it helps keep them together.
What is the recommended monitoring for patients on low molecular weight heparin?
Routine monitoring is usually not performed.
What is a common source of bleeding in surgical patients that is not surgical related?
Anticoagulant medications.
What is the original indication for TxA?
It was designed for women with extreme period bleeding.
Name two other indications for TxA.
- Epistaxis
- Oral surgery
What is Amicar primarily used for?
Almost exclusively for cardiac surgery.
What is the adult dosing range for TxA?
One to two grams.
What is the pediatric dosing for TxA?
15-20 milligrams per kilogram.
What is the discussed toxic side effect of TXA?
Loss of color vision
What is a critical consideration when discontinuing anti-platelet agents?
Consider getting platelet function panels.
What is the mortality rate associated with DIC?
Extremely high.
What initiates the process of DIC?
Widespread activation of the coagulation system.
What happens to clotting factors during DIC?
They are burned through, initially leading to widespread thrombosis.
What is a key sign of DIC?
Reduction in platelet count.
What tests are commonly used to assess DIC?
- PT
- PTT
- Thrombin time
- FDP (fibrin degradation products)
What is the primary treatment approach for DIC?
Targeted at the underlying cause.
What is Factor V Leiden?
A prothrombotic disorder where the factor V gene is mutated, leading to excessive clotting.
- Factor V is resistant to aPC, thus the negative feedback loop from IIa is less responsive.
- Or in other words, Activated protein C cannot easily stop factor V Leiden from making more fibrin.
Under what condition does Factor V Leiden typically cause issues?
During pregnancy.
What anticoagulant is commonly used for patients with Factor V Leiden?
Lovenox.
What is heparin-induced thrombocytopenia (HIT)? How often does it occur?
An autoimmune disease occurring after heparin exposure.
- Occurs in 5% of patients on heparin therapy (Most often after exposure to unfractionated heparin, but is rarely seen with LMWH)
What is the typical onset period for thrombocytopenia in HIT?
Five to fourteen days after heparin exposure.
What is thrombocytopenia?
A low platelet count, typically less than 100,000.
What should be done if a patient develops HIT?
Discontinue heparin immediately.
- Evidence suggests that HIT is mediated by immune complexes (composed of IgG antibody, platelet factor 4 [PF4], and heparin)
What alternative anticoagulants are used for patients with HIT?
- Agatroban
- Bivalirudin
What complication can arise from patients with HIT?
Increased risk of thrombosis.
What is the Apache score used for?
To evaluate patients with sepsis and DIC.
What is a significant risk factor for DIC in pregnancy?
Amniotic fluid imbalances.
What is the general approach to managing anticoagulation in patients receiving Lovenox?
Coordinate timing around doses for procedures.
What is the usual timeframe for PF4/heparin immune complexesto clear from a HIT patient’s system?
Three months
What tests are commonly checked instead of a CBC in the operating room?
- Coags
- H and H
- Basic chemistries
When might a CBC be checked in the operating room?
Widespread bleeding
What should be considered if a patient does not respond to Heparin?
Antithrombin three deficiency
What is one of the largest sources of antithrombin?
FFP
What should be done if a patient’s ACT does not change after administering Heparin?
Repeat the dose
What is the treatment for antithrombin three deficiency?
Give FFP
True or False: FFP is a clotting agent that can help anticoagulate a patient with antithrombin three deficiency.
True
What is a common initial treatment for systemic heparinization during cardiac bypass?
30,000 units of heparin
What should be done if a second bolus of Heparin does not yield results?
Consider antithrombin three deficiency
What might a surgeon complain about if a patient continues to clot after receiving Heparin?
The patient is still clotting.
- Not a serious card.
Fill in the blank: If a patient has widespread bleeding, a _______ might be checked in the operating room.
CBC
Fill in the blank: The treatment for antithrombin three deficiency is giving _______.
FFP
What should be monitored when administering heparin?
- PTT
- ACT
What is the effect of protamine on heparin?
Rapidly reversible
Protamine forms a stable complex neutralizing heparin.
How do LMWHs compare to UFH in VTE prophylaxis?
More effective
LMWHs have a more predictable pharmacokinetic response.
What is fondaparinux used for?
To treat VTE
It is a synthetic Factor Xa inhibitor.
What should be done if HIT is suspected?
- D/C heparin STAT
- Determine next anticoagulation agent
Alternative non-heparin anticoagulation must be administered.
What is the hallmark finding of HIT?
Decrease in PLT < 100,000
Usually 5-14 days after initial heparin therapy
What are antifibrinolytic agents?
- Tranexamic acid
- ε–aminocaproic acid
- Aprotinin
S/E of TXA toxicity?
Loss of color vision
What is the consequence of Factor V Leiden?
Resistant of Factor V to the action of activated protein C (More fibrin is produced so more clotting occurs)
What is a common anticoagulation option for patients with Factor V Leiden?
- Warfarin
- Unfractionated heparin infusion
- LMWH (lovenox)
What is the mechanism of action of Coumadin?
Interferes with hepatic synthesis of vitamin K-dependent coagulation factors
What is the effect of DDAVP regarding coagulation?
Stimulates the release of vWF by endothelial cells
What are common clinical features of vWF disorder?
- Easy bruising
- Recurrent epistaxis
- Menorrhagia
What is the common treatment for vWF disorder?
Correct the deficiency of vWF
This can be done using desmopressin or transfusion of specific factor.
What is a potential side effect of DDAVP?
- Headache
- Rubor
- Hypotension
- Tachycardia
- Hyponatremia
- Water intoxication
What is the impact of cryoprecipitate in treatment?
Raises fibrinogen levels by 50 mg/dL per unit
What should be restricted after administering DDAVP?
Water intake for 4 to 6 hours
What lab findings are typically seen in DIC?
- Reductions in PLT
- Prolongation of PT
- Prolongation of PTT
- Prolongation of thrombin time (TT)
- Elevated concentrations of soluble fibrin degradation products
