Ch9 Hematology Flashcards
(46 cards)
In ITP was platelet level results in ICH?
<30
What is FFP?
Plasma separated from RBCs and platelets (contains all coagulation factors)
What is the dose of FFP?
10-15ml/kg
What is cryoprecipitate?
FFP is thawed and centrifuged. The precipitate contains fibrinogen, VII, VIII and vWF. This is given in DIC therefore. Dose is 25IU/Kg.
What is prothrombin complex concentrate?
Derived from FFP. Contains factors 2, 7, 9 and 10 with protein C and protein S
What is the difference between PTCC and FFP in correcting INR?
FFP will not correct INR below 1.3.
What are the risks of anticoagulation in a patient with an incidental cerebral aneurysm?
Anticoagulation does not increase the rupture risk but does increase the morbidity / mortality should a rupture occur. Consider the PHASES score for rupture risk and if this is outweighed by the thrombosis risk e.g. CHADSVASC2 score.
Can anticoagulation be administered in patients with brain tumours.
Studies have found no increased risk of haemorrhage with anticoagulation but patients should be monitored closely.
How do you treat new onset AF within the first 48 hours?
Cardioversion
How do you quantify the risk of stroke in a patient with AF?
CHADSVASC2 score (a score of 4 equates to 4% risk per year). Warfarin reduces this risk by 2/3 so risk falls from 4% to 1.3% per year. (CHF, HTN, Age, DM, Stroke, Vasc, Sex)
How do you quantify the risk of haemorrhage in patients with anticoagulation?
HAS-BLED score ( a score of 3 equates to a 3% risk per 100 patient years but 4 is 10% per 100 patient years). HAS-BLED score is dependent on hypertension, abnormal liver / renal function, stroke, bleeding predisposition, labile INR, Elderly, Drugs.
When can you re-anticoagulate a patient following a craniotomy?
2 weeks, although some studies have shown no increase in risk after 3 days
What is the perioperative anticoagulation management of patients at high risk of thromboembolism (e.g, mechanical heart valve)?
Stop warfarin 7 days prior to surgery and given bridging therapy with LMWH (based on British Haematology Society guidelines)
What is phytomenadione?
Vitamin K (takes 8 hours to restore coagulation factors following warfarin administration)
Is bridging therapy needed for a patient with a CHADS2 score <4 and no stroke within the last 3 months?
NO
When should post-op bridging therapy with LWMH be started?
48 hours
How do you reverse warfarin for emergency surgery?
Follow local guidelines, dried prothrombin complex (octaplex) dose is 30-40 IU/Kg depending on the INR and Vitamin K 5-10 mg should also be given IV!
How do you reverse heparin?
50 mg neutralises 5000 U of heparin
How do platelets adhere to collagen?
Through the glycoprotein 1b -
How long are dual antiplatelets required after cardiac stenting?
3 months for bare metal and 1 year for drug eluting
What is the function of heparin?
Activates antithrombin 3 preventing prothrombin to thrombin and fibrinogen to fibrin
What is the action of fondaparinux?
Factor Xa inhibitor
How does Dabigatran work?
Direct thrombin (factor 2a) inhibitor - stop 72 hours prior to surgery
How do rivaroxiban, apixiban and edoxahan work?
Factor 10a inhibitors - stop 48 hours prior to surgery
