Holy Heparin
What the Warfarin
Oh My Oral Anticoagulants
Treating Pulmonary Embolisms
Beyond a Pulmonary Embolism?
100
Heparins work by binding to this protein, which will inhibitor factor Xa but also IIa/thrombin if the heparin molecules are large enough
What is antithrombin?
*Heparin itself is a large, negatively charged sulfated polysaccharide
100
Aside from reversing with vitamin K, you can give prothrombin complex concentrate (II, IX, X ± VII) or this other substance with all clotting factors
What is fresh frozen plasma (FFP)?
*Vitamin K is still the mainstay, but you could supply all clotting factors AND proteins C & S using FFP
100
Dabigatran is the oral anticoagulant used against this clotting factor, while argatroban and bivalirudin are the IV versions
What is thrombin/factor IIa?
*Know that for argatroban it has very fast onset and short half-life and has hepatic metabolism
100
Bridging would mean to switch a patient from warfarin to this anticoagulant before surgery to minimize risk of blood clots during the procedure
What is heparin?
*This is one of two major instances to have an oral and IV anticoagulant together, but you'll start IV heparin as you drop oral warfarin
100
Scuba divers can get this embolism from holding their breath in while ascending, which is called decompression sickness
What is air embolism?
*Also having an IV line with air can lead to an air embolism; treat with 100% O2 and remove source of air
200
On top of transaminitis (elevated liver enzymes) in LMWH, all heparins will have this intuitive adverse effect
What is bleeding/hemorrhage?
*You should monitor mostly UFH with aPTT or activated partial thromboplastin time
200
The exact mechanism of action for warfarin/coumadin involves inhibiting subunit-1 of this enzyme complex
What is vitamin K epoxidase reductase complex?
*This would carboxylate factors II, VII, IX, X, and also proteins C and S to activate them
200
While andexanet alfa was recently removed from being a reversing agent for direct factor Xa inhibitors, you can still use this reversal agent for dabigatran
What is idarucizumab?
*This monoclonal antibody immediate binds and reverses dabigatran's effects and will stay bound to it
200
If a DVT or PE may be fatal and thrombolytics are contraindicated, use this procedure to physically remove the clot
What is a (mechanical) thrombectomy?
*Open thrombectomies use a balloon to break the clot, while percutaneous/minimally invasive ones either soften or suck out the clot with a catheter
200
Fracturing of the marrow in long bones and the pelvis can lead to this embolism when the substance blocks venous circulation
What are fat embolisms?
*Femur, tibia, and fibula (behind tibia) in the legs are the common long bones
300
To reverse heparins, use this cationic peptide to stabilize and excrete it
What is protamine?
*Less effective the lower the molecular weight!
300
Since onset of warfarin depends more on half-lives of the clotting factors, you should monitor warfarin with this test
What is prothrombin time/international normalized ratio (PT/INR)?
*The shortest half-lives come from factor VII and protein C, so monitor using PT since extrinsic pathway is fully affected first!
300
This reversal agent does not perfectly stop direct factor Xa agents since it only binds to the factor with no catalytic activity
What is andexanet alfa?
*If it were still on the market, you would continuously give them this to hold off the factor
300
If you have a DVT, you can minimize the risk of a PE by using this clothing item that increases blood flow
What are compression stockings?
*Squeezing your legs increases pressure and thus blood flow to prevent blood pooling/stasis!
300
Common cancers that lead to tumor embolisms include GI, liver, kidney, lung, and this cancer
What is breast cancer?
*Generally associated with adenocarcinomas that are advanced and metastatic
400
The lower the heparin molecular weight, the longer the half-life but also the less effective this organ can excrete it
What is the kidney?
*Renal excretion is best with UFH, okay with LMWH, and bad with ULMWH
400
Warfarin is excreted via this organ but is not dependent on the organ's function
What is the kidney?
*The drug is mostly metabolized at this point so the unchanged drug barely exist once in the kidney
400
This direct oral anticoagulant has fecal excretion, while the other major ones are renally excreted
What is apixaban (Xa)?
*Rivaroxaban (Xa) and dabigatran (IIa) require dosing changes if there are renal problems, and argatroban is an IV anticoagulant
400
For this patient, you would want to use this broad category of drugs to immediately treat this condition
What is a systemic thrombolytic (clot buster)?
*A saddle PE warrants a thrombolytic to break the clot. Only use anticoagulants to keep a PE clot from worsening!
400
IV drug use can increase your risk for this cardiac condition which could lead to septic emboli
What is infective endocarditis?
*Non-sterile needles can have bugs like S. aureus and coagulase-negative staphylococci that can lead to such emboli
500
Heparin-induced thrombocytopenia is due to an antibody binding to this complex, leading to thrombocytopenia but paradoxically a pro-thrombotic state
What is heparin-platelet factor 4 complex?
*In most cases, treat with IV argatroban (or bivalirudin) while you let warfarin start to kick in
500
Warfarin is only orally consumed, and it will be metabolized in the liver via this specific cytochrome P450
What is CYP2C9?
*This particularly matters for dosing depending on gene variants and inhibition
500
While you should be aware of P-glycoprotein interactions for these drugs, you know interactions with this specific cytochrome P450 for direct factor Xa inhibitors
What is CYP3A4?
*Also CYP3A5 is fine!
500
If a DVT patient cannot use anticoagulants to prevent PE, use an IVC filter, where IVC stands for this
What is inferior vena cava?
*A metal cage is placed to catch clots coming into circulation from the lower body!
500
While the etiology of amniotic fluid embolisms are not known, common complications include cardiac arrest, stroke, and this uncontrollable and widespread blood clotting disorder
What is disseminated intravascular coagulation (DIC)?
*DIC happens in sepsis and cancers as well!
*These patients often need CPR, transfusions, ventilation, and even hysterectomy