Anticoagulation II

Question 1

Dalteparin in CKD

Answer 1

AVOID IN CRCL < 30

Question 2

Enoxaparin in CKD

Answer 2

CRCL 20-30: 1 mg/kg

CRCL < 20: UFH preferred, can use 0.7

Question 3

Bivalirudin in CKD

Answer 3

CRCL 30-60: 0.08 mg/kg/hr

CRCL 10-29: 0.05

IHD: 0.04

Question 4

Fondaparinux in CKD

Answer 4

CRCL < 30: Avoid in VTE

Question 5

Rule of Thumb for CKD

Answer 5

An alternative anticoagulant such as UFH may be preferred, especially for individuals with CrCL < 30 mL/min, with renal failure, or receiving dialysis

Question 6

ESRD and Hemodialysis

Answer 6

AVOID ALL LMWH

*Anti-factor Xa monitoring should be considered in patients on LMWH with CrCL < 30 mL/m

Question 7

Obesity (BMI > 40 kg/m2) Dosing

Answer 7

Fonda: 10 mg for > 100 kg for VTE

UFH: 7,500 TID or 10,000 BID, then reg

LMWH: 0.5 mg/kg, then 0.75 mg/kg BID

Question 8

Obesity and DOACs

Answer 8

1. Standard doses of apixaban, rivaroxaban, warfarin
2. Don’t use dabigatran/edoxaban/betrixaban

Question 9

Anticoagulant Recommendations in Pregnancy

Answer 9

1. LMWH preferred
2. UFH acceptable (for renal insufficiency)

AVOID warfarin/DOACs

Question 10

Anticoagulation in Pregnancy: Important Principles

Answer 10

-Preservative free preparations (prefilled syringes)
-Caution upon epidural placement
*> 24 hr from last therapeutic LMWH and epidural
*>12 hr from last prophylactic LMWH and epidural
-Avoid AC in active labor
-Consider switch to UFH at 36-37 weeks

Question 11

VTE in Cancer

Answer 11

1. Can use LMWH for initial/main tx
2. Can use apixaban/rivaroxaban/edoxaban for initial/main tx
3. May use UFH for initial tx (if CI for LMWH/DOAC)
4. LMWH/DOACs min of 6 months for cancer-associated thrombosis
5. Filter if CI to AC or recurrent VTE

Question 12

Primary Prophylaxis of Asymptomatic Carriers: Thrombophil

Answer 12

Hormonal Therapy
-Alternative contraception or avoid

Pregnancy
-Antepartum: use UFH or LMWH
-Postpartum: use UFH or LMWH or warfarin

Question 13

Secondary Event in Thrombophilias and VTE

Answer 13

-Minimum of 3-6 months of tx with inherited thrombophilia
-Consider long term tx if Protein C/S, AT3
-2+ VTEs = indefinite therapy recommended

Question 14

Determining Timing of Anticoagulant Interruption

Answer 14

Warfarin: dc 5 days prior surgery, bridge with LMWH/Heparin

UFH: dc 4 hours prior

LMWH: dc 24 hours prior

Question 15

Example of Perioperative Management of DOACs

Answer 15

Question 16

Bridging Anticoagulation (and Necessary Conditions)

Answer 16

Bridging anticoagulation involves the administration of a short-acting anticoagulant, typically a LMWH, during the interruption of a longer-acting agent, typically warfarin

SVAVS

-Embolic stroke within 12mo
-Rheumatic valvular heart disease
-Mechanical mitral valve
-Mechanical aortic valve + additional risk factors (ie. prior stroke or TIA < 6 months)
-Atrial fibrillation and CHA2DS2- VASc score ≥ 7
-VTE within 12wk
-Coronary stenting
-Recurrent VTE while on AC
-Protein C/S, AT3, APS

Question 17

Extended Prophylaxis after Discharge

Answer 17

Betrixaban
* Dose: 160 mg PO x 1 followed by 80 mg PO daily for up to 42 days

Rivaroxaban
* Dose: 10 mg PO daily for 31- 39 days (hospitalization + discharge)

Question 18

Reasons to NOT Use Pharmacologic VTE Prophylaxis: Risk Factors for Bleeding

Answer 18

-Active GI ulcer
-Bleeding 3 months prior to admission
-PLT < 50
-85+
-Hepatic failure
-Renal dysfunction
BURH 58