Anticoagulation
Start
PReP-TEAM Know Your Team - Know Your Treatment
Learning objectives e-learning
Many things can go wrong in the medication process. This may lead to hospital admission or prolonged hospital stay. The HARM Study identified anticoagulant and antiplatelet drugs as major causes of medication-related hospital admissions. One of the reasons why medication-related mistakes are made is ineffective and innefficient communication between healthcare professionals. In order to promote good teamwork between healthcare professionals, you need good experiences in interprofessional collaboration and good insight into what your colleagues know and contribute to the medication process In this e-learning you'll build common knowledge about anticoagulation so you can effectively communicate about the topic during the workgroup. You will learn about: - When you should use anticoagulants
- How the anticoagulants work
- Which things you have to look out for with anticoagulant therapy
Navigating the e-learning
When you see the icon of your profession on a page, it contains additional information specific to your profession!
NURSING
PHARMACY
MEDICINE
Chapters
What is coagulation and how does it work?
When do I use anticoagulants?
Meet our patient
Anticoagulants and their mechanisms
Key messages per profession
What is coagulation and how does it work?
What is coagulation?
When a vein is damaged, blood may leak into the tissue, causing a bruise. When the skin is broken, it causes you to openly bleed. An open cut leads to blood loss but also gives an opportunity to pathogens to enter our body. In order to prevent this from worsening, the vein has to be fixed as quickly as possible. This is done through blood clotting, also called coagulation. This process runs through several steps which involves a multitude of proteins.
Click on the bold words!
What is coagulation?
When a blood vessel is damaged, the first component of our blood that comes to the rescue are the (1) thrombocytes, also known as blood platelets. These platelets change shape when active to facilitate the formation of a "plug". This plug sits at the site of the wound to block off further blood loss. Also the muscles in vessel walls constrict to minimise blood loss. Blood platelets on themselves don't form the strongest barrier and need further adhesion to properly close off the damaged vessel. Therefore, (2) fibrinogen fibres start adhering to plug as well for a stronger barrier. Outside the blood vessel, on the surface of the wound, the fibrinogen proteins get exposed to (3) thrombin, which is not normally found within the blood vessel. This exposure turns them into sticky fibrin fibers, making even more blood platelets, (4) blood cells, and other blood components to stick. The clot is formed and develops into a (5) scab. Underneath, the skin and blood vessel start (6) healing again.
The coagulation cascade
The coagulation cascade is a very complex process with many interdependent proteins as you can see in the figure. In the end, the goal of the coagulation cascade is the formation of a blood clot to prevent bleeding. Anticoagulants target some of these proteins which will lead to decreased production of cross-linked fibrin clots. You can see how these work in the following chapters of this e-learning.
Measuring coagulation
Click on the bold words!
intrinsic = APTT
extrinsic = = INR
00:00
How fast the coagulation cascade finishes is measured with the (1) prothrombin time (PT). A prolonged PT means either an issue in the extrinsic pathway or the intended effect of anticoagulation. However, not all laboratories measure the PT in the same way. That's why an (2) international WHO standard is used as a reference value. This is then used to calculate the (3) International Normalized Ratio (INR). This INR is the ratio between a "normalized" PT (e.g. 12 seconds) and patients' PT. A person with regular coagulation would have the standard INR=1. When you use vitamin K antagonists (VKAs), the target values for the INR would be 2.0-3.0, or 2.5-3.5 for patients with a mechanical heart valve. On the other hand, we have the (4) Activated Partial Thromboplastin Time (APTT). This measures the speed of the intrinsic coagulation cascade. Normally APTT is 20-30 seconds, but with anticoagulation therapy this increases to 50-80 seconds. Reference values may differ depending on the lab that measures the APTT.
What is the CHADS-VASc score?
1 pt
Congestive heart failure
Sometimes a complication only requires anticoagulation when you've properly balanced out the risks of (excessive) coagulation and (excessive) bleeding. This can be assessed with the CHADS-VASc score, which scores the risk of a stroke based on certain riskfactors. Try to recall for yourself which riskfactors contribute to an increased risk of stroke. Click on the Letters for the answers.
1 pt
Hypertension
A2
2 pt
Age > 75 years
1 pt
Diabetes
S2
2 pt
Stroke
1 pt
Vascular disease
1 pt
Age 65-74 years
1 pt
Sex category (Female)
Sc
02
when do i use anticoagulants?
Complications in Coagulation
Prevention of venous thrombo-embolism (VTE)
Treatment of VTE's
Prevention of thrombo-embolism with atrial fibrillation or mechanical heart valve
Indications for anticoagulation
As you have seen, coagulation is a complex and intricate process. So when complications in this process occur (primarily in excess), we wish to decrease the rate of coagulation as this can lead to unwanted clotting.
For which general indications are anticoagulants used? Click the button below for feedback.
ANSWER
When to use anticoagulants
There are some exceptions to the indications. Some examples are given here. Click the box if you think the anticoagulant applies to the indication. When finished, click here to see the answer.
Prevention of VTE complications after hip or knee replacement surgery
Patients with a mechanical heart valve
Prevention of thrombo-embolism with atrial fibrillation
Short notice surgical procedures
High risk (life-threatening) lung embolism
Bridging of oral anticoagulation
03
Meet our patient
Meet Our Patient
Mr. Whitaker
Mr. Whitaker is 76 years old and suffers from atrial fibrillation (AF). He takes apixaban twice daily for his AF. Mr Whitaker will have to be admitted to the hospital for an elective knee surgery in two weeks, which means some of his medication has to be paused. This causes a lot of confusion for him. "Why do I need to stop certain medication and continue with others? I have been taking my medication very consistenly and staying active so my heart stays good too! I hope they won't change too much..." Sometimes he doesn't want to take his medications. He says that he has been getting more bruises after he was diagnosed with atrial fibrillation.
Mr. Whitaker's medication history
Apixaban is used for Mr. Whitaker's AF. Which other medication could be indicated for AF as well? Click on the medications in the medication history below you think are indicated for AF. Click here to see the answers.
Current medication:- Metoprolol
- Candesartan
- Lorazepam
- Amitriptyline
- Apixaban
- Povidone eye drops
- Omeprazole
- Paracetamol
Medication from history: - Diltiazem
- Acenocoumarol
- Enalapril
- Metoprolol is a bèta-blocker and "adjusts" the heart rate in AF
- Candesartan is an ARB and is used to treat hypertension/heart failure
- Lorazepam is a benzodiazpine and is used for sleep complications
- Amitriptyline is a tricyclic antidepressant and is not used to treat AF
- Povidone eye drops are used to treat Mr. Whitaker's dry eyes
- Omeprazole is a PPI and is used to treat excessive acid in the stomach
- Paracetamol is a painkiller and is not used directly to treat AF
- Apixaban is a DOAC and prevents blood clotting due to AF
- Diltiazem is a calcium antagonist and "adjusts" the heart rate in AF
- Enalapril is an ACE-inhibitor and is used to treat hypertension/heart failure
- Acenocoumarol is a VKA and prevents blood clotting due to AF
- Correct! Metoprolol is a bèta-blocker and "adjusts" the heart rate in AF
- Candesartan is an ARB and is used to treat hypertension/heart failure
- Lorazepam is a benzodiazpine and is used for sleep complications
- Amitriptyline is a tricyclic antidepressant and is not used to treat AF
- Correct! Apixaban is a DOAC and prevents blood clotting due to AF
- Povidone eye drops are used to treat Mr. Whitaker's dry eyes
- Omeprazole is a PPI and is used to treat excessive acid in the stomach
- Paracetamol is a painkiller and is not used directly to treat AF
- Correct! Diltiazem is a calcium antagonist and "adjusts" the heart rate in AF
- Correct! Acenocoumarol is a VKA and prevents blood clotting due to AF
- Enalapril is an ACE-inhibitor and is used to treat hypertension/heart failure
anticoagulants and their mechanisms
The Different Anticoagulants
In short, these are the different anticoagulants that are used to treat excessive clotting.To jump to one anticoagulant-group, click
+ INFO
Low Molecular Weight Heparins
Vitamin K Antagonists
Direct Oral Anticoagulants
Heparin
+ INFO
+ INFO
+ INFO
+ INFO
Click on the bold words!
Vitamin K antagonists (VKAs)
VKAs inhibit the enzyme (1) vitamine K-epoxide-reductase. This breaks down the vitamin K production cycle. (2) Procoagulation factors IX, X, XII and II are vitamin K dependent for their production. You can remember this with the mnemonic 1972. Inhibiting these will prevent formation of (3) fibrin clots. Anti-coagulant factors (4) APC and protein S are vit. K dependent as well and react faster to a decreased vit. K than the other factors. That's why the first few days, there is more net bleeding than net anticoagulation. Important to note is that ALREADY PRODUCED procoagulation factors are NOT impacted, only the production of NEW factors.
Things to look out for with VKA use
VKAs inhibit coagulation, so the risk of bleeding is increased. Important signs of bleeding to look out for is (excessive) bruising and blood in the stool of patients. These are cases of internal bleeding.
What adverse effects can occur?How do you observe and treat them?
VKAs can't be used in all cases. Contra-indications are: pregnancy, use close to surgery of the eye or central nervous system, bleeding tumors, sepsis or increased fibrinolytic activity. An increased risk of bleeding with these indications is of higher concern. VKAs cross the placental barrier, which can lead to deformities in the unborn child, which makes the use in pregnancy dangerous.
Which complications or patient characteristics are not suitable for VKA use?
Click on the boxes to see the answer
Vitamin K is a natural antagonist of a VKA. Try to keep food intake with high vitamin K content (like green leafy vegatables) to a minimum. Substances that can increase bleeding, like alcohol, nicotine NSAIDs and corticosteroids, can lead to more substantial bleeding in combination with a VKA. Other interactions to look out for are CYP-interactions.
What comedications or substances should not be taken concomitantly with VKAs?
Dosing of VKAs
2-3 days
1 day
It takes some time before a VKA has reached full effect, because they only inhibit production of NEW factors . That's why we start with a loading dose. How long does this loading phase take normally?
1 week
5-6 days
2.0-3.0
1.5-2.5
(Maintanance) dosage of VKAs depends on the indication and the INR. This is adjusted routinely. What is the INR reference range?
2.5-3.5
3.0-4.0
Fytomenadion
Andexanat ɑ
In case of a patient bleed, we measure the INR and stop lower the dose or stop the VKA. In case of a heavier bleeding, an antidote might be necessary. Which antidote may be appropriate in this case?
Idarucizumab
Cofact
Click on the bold words!
Direct Oral AntiCoagulants (DOACs)
DOACs have a similar effectiveness as the VKAs, but directly inhibit the coagulation factors. These are the (1) factor Xa for apiXaban, rivaroXaban and edoXaban and (2) thrombin for dabigatran. DOACs have a shorter halftime than VKA's: 2 vs. 5 days. This makes DOACs safer to use around high-risk operations. There's also no need for routine screening.
Things to look out for with DOAC use
There are several DOAC specific antidotes: Idaracuzimab for dabigatran and Andexanet alfa for apixaban and rivaroxaban. Edoxaban does not have a registered specific antidote yet. In case these antidotes aren't available, prothrombin complex (Cofact) can be used.
How do you treat bleedings caused by DOACs? Which antidotes are available?
Age, bodyweight, and kidney function are the main patient characteristics to take into account. In case a patient is older, has a lower weight or decreased kidney function the dosage is lowered.
What patient characteristics decide the dosage of DOACs?
Click on the boxes to see the answer
Important interactions to look out for are with CYP3A4 or Pgp-inducers & inhibitors. Examples of inducers are rifampicin or carbamapazin. These lower the DOAC concentration (decreased anticoagulant effect). Examples or inhibitors are antifungal medication (-azoles) and HIV protease inhibitors, like ritonavir. These increase DOAC levels (increased bleeding risk).
What comedications or substances should not be taken concomitantly with DOACs?
Dosing of DOACs
70 years
65 years
From what age should you consider halving the dosage of apixaban as a risk factor?
80 years
75 years
60
80
Below which kidney function (in creatinine clearance ml/min) is dabigatran contra-indicated for adult patients?
50
30
1: True | 2: True
1: True | 2: False
(1) It is possible to directly switch from a VKA to a DOAC without overlap. (2) It is possible to directly switch from a DOAC to a VKA without overlap.
1: False | 2: False
1: False | 2: True
Click on the bold words!
Low Molecular Weight Heparins (LMWH) & Heparins
Unfractionated heparin (UFH) directly inhibits activated coagulation factors, (1) thrombin and (2) factor Xa. In low doses, heparin mainly targets Xa, in high doses heparin also thrombin. It works quickly, after intravenous administration within 20-60 minutes. Its effect is sustained over 12-24 hours. Heparin also (3) activates anti-thrombin (III) to a lesser extent. LMWHs contain heparin fragments with a lower molecular weight. The smaller fragments stick less to the arterial walls or proteins, which makes their effect a lot more predictable. LMWHs are 2-3 times more active against factor Xa than thrombin compared to UFH.
Things to look out for with heparin/LMWH use
Bleeding is a major concern with heparin and LMWHs, but heparin induced thrombocytopenia (HIT) can occur in rare cases. This is a life threatening syndrome, which develops within 5-15 days after exposure to heparin or LMWHs. The chances of developing HIT are lower with LMWH use than unfractionated heparin. HIT is diagnosed based on clinical symptoms such as fever, hypertension, tachycardia, shortness of breath and thrombotic events. In lab testing, you observe decreased platelet count. The heparin should be stopped and the patient should never receive UFH or LMWHs again, as a "cross-reaction" may occur. It is important to register this as a contra-indication. As an alternative, danaparoid of fondaparinux may be used as substitute fast-acting anticoagulants without eliciting HIT.
Click here to see how HIT develops
Measuring effectiveness
The activity of UFH is measured with an aPTT screening (do you remember what this value is with heparin use?). It is important to time this measurement well to get a good indication of the effect. When should the aPTT be measured with heparin use? Click on timeline below. apTT should be measured [...] after UFH initation
Because an LMWH mostly targets factor Xa, the effectiveness in therapeutic use is measured through anti-Xa activity screening. This is not always relevant to measure, only for certain patients. Which of the following factors does NOT require anti-Xa screening?
Obesity Decreased kidney function (< 30 ml/min) Liver disease Pregnancy Hypertension Neonates/children
The Tmax of heparins is roughly 4 hours. That's the best time to measure the aPTT.
7hr.
4hr.
1hr.
8hr.
9hr.
10hr.
5hr.
6hr.
2hr.
3hr.
Dosing UFH & LMWH
Heparin is dosed based on kg AND the aPTT, where adjustment of dosage may be necessary. That's why administrating heparin via pump is more convenient, as you can adjust the administration rate quickly.
LMWHs are dosed per weight-range. For nadroparin for example: 5700 IE for 60–69 kg, 4750 IE for 50-59 kg. In patients with obesity, it's not clear yet what the optimal dosing is; whether it should be capped or still dosed based on bodyweight. Anti-Xa screenings are also not accurate. So in obese patients, dosing LMWHs can be quite difficult.
UFH and LMWH are dosed based on weight and indication. For LMWH, kidney function is important as well, as it is excreted via the kidneys.
Protamine can be used as an antidote for UFH but is less effective against LMWHs (25-50% effective)
Both are used either intravenously or subcutaneously.
+ INFO
Considerations for anticoagulants
Certain things are important to consider when working with anticoagulants for Mr. Whitaker. Click on the (+) for more information about these different considerations for each anticoagulant group. Click on the (+) again to hide the Tooltip. After this, we wrap up the e-learning with 6 follow-up questions with Mr. Whitaker.
DOACs and VKAs are first choice to prevent and treat thrombo-embolic events. Nowadays, patients are almost always started on DOACs unless there's a contra-indication. Patients who use VKAs and react well to them are mostly kept on VKAs and are not necessarily switched to DOACs. LMWHs and heparin are used as prophylaxis of thrombo-embolic events, especially in cases where oral anticoagulants are not appropriate, for example right after surgeries, when anticoagulation is urgent, or in pregnancy.
Because DOACs have a set dose, it's more patient friendly. The frequent dose monitoring and dose adjustments of the VKA's make it less patient friendly. Because LMWHs/heparins are taken intravenously or subcutaneously, it's less patient friendly. That's why their use is limited to bridging in an outpatient setting.
For patients with an inconsistent lifestyle, DOACs are preferable. When it comes to polypharmacy, both VKAs and DOACs have many drug-interactions. That's why it's important to stay vigilant of a patient's medication list. For patients in unstable conditions or declining health, keeping an eye on their kidney function can be crucial, as DOAC dosage may have to be adjusted. DOACs may also not be used in patients with a mechanical heart valve.
DOACs generally don't require monitoring, whereas VKAs require regular monitoring of the INR to adjust dosage. LMWHs and heparin do not require routine monitoring for prophylactic doses, but may require monitoring at therapeutic doses. This is only the case with certain characteristics; in children, and patients with decreased kidney function, high BMI, or pregnancy.
DOACs have a similar (and possibly even lower) risk of bleeding compared to VKAs. With VKAs, however, these risks are easier to monitor when the INR gets too high. Both have their specific antidotes, where fytomenadion is cheaper than idarucizumab or andexanet alfa. LMWHs and heparins have a higher bleeding risk, especially in higher doses. That's why for therapeutic use with high doses, an intramural setting with controlled patient monitoring is more appropriate.
Follow-up with our patient
(1 of 2)
Mr. Whitaker's surgery
In a few days, our patient's surgery is planned. The orthopedic surgeon advises to discontinue his apixaban a few days before the procedure to minimize bleeding risks during surgery.
How many days before the scheduled knee replacement surgery should Mr. Whitaker discontinue his apixaban?
How many hours post surgery should he resume his apixaban to balance risk of thrombosis and bleeding?
5 days
3 days
1 day
48 hours
7 days
24 hours
1 hour
72 hours
Patients receiving an elective knee surgery on apixaban should always be bridged with an LMWH.
Which laboratory test is most appropriate for assessing bleeding risk pre-surgery (considering apixaban)?
INR
aPTT
PT
Anti-Xa
False
True
Follow-up with our patient
(2 of 2)
Mr. Whitaker's surgery
In a few days, our patient's surgery is planned. The orthopedic surgeon advises to discontinue his apixaban a few days before the procedure to minimize bleeding risks during surgery.
What key information should Mr. Whitaker receive regarding the resumption of apixaban after surgery?
In which of these scenario's would bridging therapy NOT be advisable for a patient with VKA use?
"Resume apixaban immediately after surgery to prevent blood clots."
The patient has a mechanical heart valve
"Wait until the surgical wound is completely healed before restarting apixaban."
The patient suffers from AF or a CHA2DS2VASc > 5
"Contact your healthcare provider if you experience unusual bleeding/bruising after restarting apixaban."
The patient has a decreased kidney function
"Take a higher dose of apixaban for the first week after surgery."
The patient had a stroke, episode of systemic emboli or VTA in the last 3 months
05
key messages per profession
Proceed for
Pharmacy | Nursing | Medicine
Anticoagulation | Pharmacy
- Regular monitoring and assessment of coagulation parameters is necessary for effective and safe treatment.
- Individual variations in patient characteristics (especially metabolism) may influence the response to anticoagulants. Personalised care is important
- Identify and avoid drug interactions and contraindications of anticoagulants, especially in patients with complex drug regimens.
- Collaboration with physicians and nurses, in managing anticoagulation is important in reducing risks to patients.
Finish the e-learning
Anticoagulation | Pharmacy
- Regular monitoring and assessment of coagulation parameters is necessary for effective and safe treatment.
- Be wary of bleeding in patients, mainly in the form of bruising. Try to keep these bleeding risks to a minimum.
- The use of VKAs can be complicated for patients due to adjustments in doses. Therefore, monitor adherence carefully.
- Subcutaneous administration of LMWHs can also be a problem. In this, good guidance is crucial.Collaboration with doctors and nurses, in managing anticoagulation is important in reducing risks for patients.
Finish the e-learning
Anticoagulation | MEDICINE
- DOACs are now first choice for oral anticoagulation, but there are still exceptions. Prefer to keep patients who respond well to VKAs on VKAs.
- The coagulation cascade offers great insight into when and why anticoagulants work. Knowing and understanding this helps with pharmaceutical decision making.
- HITs are rare but life-threatening. Stay vigilant for symptoms that arise after a few days that may indicate this.
- Collaboration with pharmacists and nurses, in managing anticoagulation is important in reducing risks to patients.
Finish the e-learning
You've finished this e-learning!
We've gone through several aspects of anti-coagulation for the different professions. We will discuss your perceptions of roles and responsibilities in pharmacotherapy and work on a case-simulation in interprofessional groups. For this, do the following: 1) Reflect on these statements and bring you answers to the workgroup.- How do you represent your health care profession in anticoagulation therapy?What are your responsibilities?
- How do you think other health care professions are involved in this process?
- What skills/competencies do you need to possess to participate in collaborative practice?
2) Download the app Team Up! Find Team Up! in the Google Play Store/App store or scan the QR codes below.
Google Play Store
App Store
This is the right answer
Apixaban has bleedings as the most obvious side-effect. The key word here is unusual. Bruising occurs often, but when this becomes excessive, a healthcare provider must be informed.
This is the wrong answer
Knee surgeries have an intermediate risk of bleeding. For apixaban, cessation 1 day before surgery is the sufficient. Longer cessation increases the risk of thrombosis. In case the patient has a decreased kidney function, we should cessate apixaban 36 hours before surgery. Do you know why?
This is the wrong answer
Restarting apixaban immediately after surgery increases the bleeding risk. We have to postpone the restart for longer than 1 hour.
This is the right answer
Once a creatinine clearance below 30 ml/min is reached, the chances of dabigatran accumulation is greatly increased. In that case, dabigatran should be avoided. Of all DOACs, apixaban is cleared the least by the kidneys. So apixaban is the safest option for patients with kidney diseases.
This is the wrong answer
We aim to achieve a lower INR with VKAs. Multiple options may be correct.
Try to think based on the mechanism of action.
This is the wrong answer
When a patient is exposed to (1) heparin, it can bind to (2) platelet factor 4. This complex becomes immunogenic and attracts an (3) antibody, often IgG. The antigen-antibody complexes bind to platelets, leading to (4) platelet activation. This causes 2 important things:1. Release of prothrombotic (5) microparticles2. (6) Platelet consumptionThe platelet consumption leads to thrombocytopenia. The microparticles promote more thrombin production, which leads to thrombosis.You can find more information on HIT here.
This is the right answer
To avoid any VTEs due to his atrial afibrillation, restartin apixaban in time is important. This is 24 hours after his surgery.
This is the right answer
For patients with high-intensity therapy of VKAs, we strive to achieve an INR of 2.5-3.5. What range do we use for patients with low-intensity therapy?
This is the right answer
It can take about 2-3 days before optimal effect is reached. This is often bridged with a LMWH to make sure anticoagulation still takes place within these days.
When a VKA is switched to a DOAC, the DOAC should be administered only if the INR < 2 to reduce the risks of bleeding, because the effect of the VKA still lingers on. On the other hand, if a DOAC is to switched to a VKA, then the DOAC should be ceased until adequate INR > 2 is achieved. Because it take longer for VKA’s to be optimally effective.
This is the wrong answer
This is the wrong answer
Click on (X) to try again.
This is the wrong answer
Restarting apixaban 72 hours after surgery increases the risk of thrombosis as he won't be treated for his atrial afibrillation in time.
It takes some days before the optimal effect of VKAs is reached.
This is the wrong answer
This is the right answer
Other risk factors are a body weight < 60 kg and a serum creatinin > 133 µmol/L. When a patient has 2 of the 3 mentioned risk factors, the apixaban dosage should be halved.
This is the right answer
Fytomenadion is simply Vitamin K. Its maximal effect is reached after 24 hours, after which it's still active over 24-48 hours. That's why it's important to keep monitoring the INR for an extended period of time. Because fenprocoumon has a much longer halflife than acenocoumarol (160 hours vs 8-11 hours), there's a difference in follow-up time: 4 days for acenocoumarol, 2 weeks for fenprocomoun.
This is the wrong answer
Taking a higher dose for the first week applies to the therapeutic use of apixaban. In this case treatment goal is preventive: avoid a VTE due to his AF.
We aim to achieve a higher INR with VKAs. Multiple options may be correct.
This is the wrong answer
This is the wrong answer
When a VKA is switched to a DOAC, the DOAC should be administered only if the INR < 2 to reduce the risks of bleeding, because the effect of the VKA still lingers on. On the other hand, if a DOAC is to switched to a VKA, then the DOAC should be ceased until adequate INR > 2 is achieved. Because it take longer for VKA’s to be optimally effective.
Bridging with an LMWH is not indicated for DOAC use. This is because both medication groups have a similar T1/2. Bridging with an LMWH would give a similar effect as continuing the apixaban.
This is the right answer
This is the wrong answer
The healing process can take quite some time. If we restart only when it's healed, too much time has elapsed where the patient remains untreated for his AF.
This is the wrong answer
The optimal effect of VKAs takes some days to reach, but already occurs within a few days.
This is the right answer
When a VKA is switched to a DOAC, the DOAC should be administered only if the INR < 2, to reduce the risks of bleeding. When a DOAC is to switched to a VKA, then the DOAC should be ceased only when an adequate INR > 2 is achieved, to reduce risk of thrombosis.
This is the wrong answer
Idarucizumab is the antidote for a specfic DOAC and is not effective against VKAs.
This is the wrong answer
When a VKA is switched to a DOAC, the DOAC should be administered only if the INR < 2 to reduce the risks of bleeding, because the effect of the VKA still lingers on. On the other hand, if a DOAC is to switched to a VKA, then the DOAC should be ceased until adequate INR > 2 is achieved. Because it take longer for VKA’s to be optimally effective.
This is the wrong answer
The optimal effect of VKAs takes some days to reach, but already occurs within a few days.
Bridging with an LMWH is not indicated for DOAC use. This is because both medication groups have a similar T1/2. Bridging with an LMWH would give a similar effect as continuing the apixaban.
This is the wrong answer
This is the wrong answer
Click on (X) to try again.
This is the wrong answer
Restarting apixaban immediately after surgery increases the bleeding risk. We have to postpone the restart to 24 hours after surgery.
Click on (X) to try again.
This is the wrong answer
Decreased kidney function does not immediately put the patient in a risk group for increased thrombotic event occurence. Although it does affect the clearance of some anticoagulants.
This is the right answer
Andexanet Alfa is an antidote for certain DOACs, but is not effective as an antidote for VKAs.
This is the wrong answer
Apixaban inhibits factor Xa, so assessing with an anti-Xa screening is the most appropriate. However, this almost never done.
This is the right answer
Click on (X) to try again.
This is the wrong answer
This is the wrong answer
Click on (X) to try again.
This factor puts the patient in a risk group for the occurence of VTEs. In order to prevent these, bridging therapy is advised (but not for a DOAC with LMWHs as you've seen).
This is the wrong answer
This is the right answer
For patients with low-intensity therapy of VKAs, we strive to achieve an INR of 2.0-3.0. What range do we use for patients with high-intensity therapy?
This is the wrong answer
Click on (X) to try again.
This is the wrong answer
Knee surgeries have an intermediate risk of bleeding. For apixaban, cessation 1 day before surgery is the sufficient. Longer cessation increases the risk of thrombosis. In case the patient has a decreased kidney function, we should cessate apixaban 36 hours before surgery. Do you know why?
This is the wrong answer
Restarting apixaban 48 hours after surgery increases the risk of thrombosis as he won't be treated for his atrial afibrillation in time.
This is the right answer
Knee surgeries have an intermediate risk of bleeding. For apixaban, cessation 1 day before surgery is the sufficient. Longer cessation increases the risk of thrombosis. In case the patient has a decreased kidney function, we should cessate apixaban 36 hours before surgery. Do you know why?
This is the right answer
Cofact, also known as prothrombin complex, is a mix of different coagulation factors which have been inhibited by anticoagulants. The excessive depletion by VKA will be counteracted by supplying more factors. Cofact is a good option in case fytomenadion was not effective enough.
Anticoagulation - ENG
PReP TEAM (PReP TEAM
Created on July 11, 2023
Start designing with a free template
Discover more than 1500 professional designs like these:
View
Higher Education Presentation
View
Psychedelic Presentation
View
Vaporwave presentation
View
Geniaflix Presentation
View
Vintage Mosaic Presentation
View
Modern Zen Presentation
View
Newspaper Presentation
Explore all templates
Transcript
Anticoagulation
Start
PReP-TEAM Know Your Team - Know Your Treatment
Learning objectives e-learning
Many things can go wrong in the medication process. This may lead to hospital admission or prolonged hospital stay. The HARM Study identified anticoagulant and antiplatelet drugs as major causes of medication-related hospital admissions. One of the reasons why medication-related mistakes are made is ineffective and innefficient communication between healthcare professionals. In order to promote good teamwork between healthcare professionals, you need good experiences in interprofessional collaboration and good insight into what your colleagues know and contribute to the medication process In this e-learning you'll build common knowledge about anticoagulation so you can effectively communicate about the topic during the workgroup. You will learn about:- When you should use anticoagulants
- How the anticoagulants work
- Which things you have to look out for with anticoagulant therapy
Navigating the e-learning
When you see the icon of your profession on a page, it contains additional information specific to your profession!
NURSING
PHARMACY
MEDICINE
Chapters
What is coagulation and how does it work?
When do I use anticoagulants?
Meet our patient
Anticoagulants and their mechanisms
Key messages per profession
What is coagulation and how does it work?
What is coagulation?
When a vein is damaged, blood may leak into the tissue, causing a bruise. When the skin is broken, it causes you to openly bleed. An open cut leads to blood loss but also gives an opportunity to pathogens to enter our body. In order to prevent this from worsening, the vein has to be fixed as quickly as possible. This is done through blood clotting, also called coagulation. This process runs through several steps which involves a multitude of proteins.
Click on the bold words!
What is coagulation?
When a blood vessel is damaged, the first component of our blood that comes to the rescue are the (1) thrombocytes, also known as blood platelets. These platelets change shape when active to facilitate the formation of a "plug". This plug sits at the site of the wound to block off further blood loss. Also the muscles in vessel walls constrict to minimise blood loss. Blood platelets on themselves don't form the strongest barrier and need further adhesion to properly close off the damaged vessel. Therefore, (2) fibrinogen fibres start adhering to plug as well for a stronger barrier. Outside the blood vessel, on the surface of the wound, the fibrinogen proteins get exposed to (3) thrombin, which is not normally found within the blood vessel. This exposure turns them into sticky fibrin fibers, making even more blood platelets, (4) blood cells, and other blood components to stick. The clot is formed and develops into a (5) scab. Underneath, the skin and blood vessel start (6) healing again.
The coagulation cascade
The coagulation cascade is a very complex process with many interdependent proteins as you can see in the figure. In the end, the goal of the coagulation cascade is the formation of a blood clot to prevent bleeding. Anticoagulants target some of these proteins which will lead to decreased production of cross-linked fibrin clots. You can see how these work in the following chapters of this e-learning.
Measuring coagulation
Click on the bold words!
intrinsic = APTT
extrinsic = = INR
00:00
How fast the coagulation cascade finishes is measured with the (1) prothrombin time (PT). A prolonged PT means either an issue in the extrinsic pathway or the intended effect of anticoagulation. However, not all laboratories measure the PT in the same way. That's why an (2) international WHO standard is used as a reference value. This is then used to calculate the (3) International Normalized Ratio (INR). This INR is the ratio between a "normalized" PT (e.g. 12 seconds) and patients' PT. A person with regular coagulation would have the standard INR=1. When you use vitamin K antagonists (VKAs), the target values for the INR would be 2.0-3.0, or 2.5-3.5 for patients with a mechanical heart valve. On the other hand, we have the (4) Activated Partial Thromboplastin Time (APTT). This measures the speed of the intrinsic coagulation cascade. Normally APTT is 20-30 seconds, but with anticoagulation therapy this increases to 50-80 seconds. Reference values may differ depending on the lab that measures the APTT.
What is the CHADS-VASc score?
1 pt
Congestive heart failure
Sometimes a complication only requires anticoagulation when you've properly balanced out the risks of (excessive) coagulation and (excessive) bleeding. This can be assessed with the CHADS-VASc score, which scores the risk of a stroke based on certain riskfactors. Try to recall for yourself which riskfactors contribute to an increased risk of stroke. Click on the Letters for the answers.
1 pt
Hypertension
A2
2 pt
Age > 75 years
1 pt
Diabetes
S2
2 pt
Stroke
1 pt
Vascular disease
1 pt
Age 65-74 years
1 pt
Sex category (Female)
Sc
02
when do i use anticoagulants?
Complications in Coagulation
Prevention of venous thrombo-embolism (VTE)
Treatment of VTE's
Prevention of thrombo-embolism with atrial fibrillation or mechanical heart valve
Indications for anticoagulation
As you have seen, coagulation is a complex and intricate process. So when complications in this process occur (primarily in excess), we wish to decrease the rate of coagulation as this can lead to unwanted clotting.
For which general indications are anticoagulants used? Click the button below for feedback.
ANSWER
When to use anticoagulants
There are some exceptions to the indications. Some examples are given here. Click the box if you think the anticoagulant applies to the indication. When finished, click here to see the answer.
Prevention of VTE complications after hip or knee replacement surgery
Patients with a mechanical heart valve
Prevention of thrombo-embolism with atrial fibrillation
Short notice surgical procedures
High risk (life-threatening) lung embolism
Bridging of oral anticoagulation
03
Meet our patient
Meet Our Patient
Mr. Whitaker
Mr. Whitaker is 76 years old and suffers from atrial fibrillation (AF). He takes apixaban twice daily for his AF. Mr Whitaker will have to be admitted to the hospital for an elective knee surgery in two weeks, which means some of his medication has to be paused. This causes a lot of confusion for him. "Why do I need to stop certain medication and continue with others? I have been taking my medication very consistenly and staying active so my heart stays good too! I hope they won't change too much..." Sometimes he doesn't want to take his medications. He says that he has been getting more bruises after he was diagnosed with atrial fibrillation.
Mr. Whitaker's medication history
Apixaban is used for Mr. Whitaker's AF. Which other medication could be indicated for AF as well? Click on the medications in the medication history below you think are indicated for AF. Click here to see the answers.
Current medication:- Diltiazem
- Acenocoumarol
- Enalapril
- Metoprolol
- Candesartan
- Lorazepam
- Amitriptyline
- Apixaban
- Povidone eye drops
- Omeprazole
- Paracetamol
Medication from history:anticoagulants and their mechanisms
The Different Anticoagulants
In short, these are the different anticoagulants that are used to treat excessive clotting.To jump to one anticoagulant-group, click
+ INFO
Low Molecular Weight Heparins
Vitamin K Antagonists
Direct Oral Anticoagulants
Heparin
+ INFO
+ INFO
+ INFO
+ INFO
Click on the bold words!
Vitamin K antagonists (VKAs)
VKAs inhibit the enzyme (1) vitamine K-epoxide-reductase. This breaks down the vitamin K production cycle. (2) Procoagulation factors IX, X, XII and II are vitamin K dependent for their production. You can remember this with the mnemonic 1972. Inhibiting these will prevent formation of (3) fibrin clots. Anti-coagulant factors (4) APC and protein S are vit. K dependent as well and react faster to a decreased vit. K than the other factors. That's why the first few days, there is more net bleeding than net anticoagulation. Important to note is that ALREADY PRODUCED procoagulation factors are NOT impacted, only the production of NEW factors.
Things to look out for with VKA use
VKAs inhibit coagulation, so the risk of bleeding is increased. Important signs of bleeding to look out for is (excessive) bruising and blood in the stool of patients. These are cases of internal bleeding.
What adverse effects can occur?How do you observe and treat them?
VKAs can't be used in all cases. Contra-indications are: pregnancy, use close to surgery of the eye or central nervous system, bleeding tumors, sepsis or increased fibrinolytic activity. An increased risk of bleeding with these indications is of higher concern. VKAs cross the placental barrier, which can lead to deformities in the unborn child, which makes the use in pregnancy dangerous.
Which complications or patient characteristics are not suitable for VKA use?
Click on the boxes to see the answer
Vitamin K is a natural antagonist of a VKA. Try to keep food intake with high vitamin K content (like green leafy vegatables) to a minimum. Substances that can increase bleeding, like alcohol, nicotine NSAIDs and corticosteroids, can lead to more substantial bleeding in combination with a VKA. Other interactions to look out for are CYP-interactions.
What comedications or substances should not be taken concomitantly with VKAs?
Dosing of VKAs
2-3 days
1 day
It takes some time before a VKA has reached full effect, because they only inhibit production of NEW factors . That's why we start with a loading dose. How long does this loading phase take normally?
1 week
5-6 days
2.0-3.0
1.5-2.5
(Maintanance) dosage of VKAs depends on the indication and the INR. This is adjusted routinely. What is the INR reference range?
2.5-3.5
3.0-4.0
Fytomenadion
Andexanat ɑ
In case of a patient bleed, we measure the INR and stop lower the dose or stop the VKA. In case of a heavier bleeding, an antidote might be necessary. Which antidote may be appropriate in this case?
Idarucizumab
Cofact
Click on the bold words!
Direct Oral AntiCoagulants (DOACs)
DOACs have a similar effectiveness as the VKAs, but directly inhibit the coagulation factors. These are the (1) factor Xa for apiXaban, rivaroXaban and edoXaban and (2) thrombin for dabigatran. DOACs have a shorter halftime than VKA's: 2 vs. 5 days. This makes DOACs safer to use around high-risk operations. There's also no need for routine screening.
Things to look out for with DOAC use
There are several DOAC specific antidotes: Idaracuzimab for dabigatran and Andexanet alfa for apixaban and rivaroxaban. Edoxaban does not have a registered specific antidote yet. In case these antidotes aren't available, prothrombin complex (Cofact) can be used.
How do you treat bleedings caused by DOACs? Which antidotes are available?
Age, bodyweight, and kidney function are the main patient characteristics to take into account. In case a patient is older, has a lower weight or decreased kidney function the dosage is lowered.
What patient characteristics decide the dosage of DOACs?
Click on the boxes to see the answer
Important interactions to look out for are with CYP3A4 or Pgp-inducers & inhibitors. Examples of inducers are rifampicin or carbamapazin. These lower the DOAC concentration (decreased anticoagulant effect). Examples or inhibitors are antifungal medication (-azoles) and HIV protease inhibitors, like ritonavir. These increase DOAC levels (increased bleeding risk).
What comedications or substances should not be taken concomitantly with DOACs?
Dosing of DOACs
70 years
65 years
From what age should you consider halving the dosage of apixaban as a risk factor?
80 years
75 years
60
80
Below which kidney function (in creatinine clearance ml/min) is dabigatran contra-indicated for adult patients?
50
30
1: True | 2: True
1: True | 2: False
(1) It is possible to directly switch from a VKA to a DOAC without overlap. (2) It is possible to directly switch from a DOAC to a VKA without overlap.
1: False | 2: False
1: False | 2: True
Click on the bold words!
Low Molecular Weight Heparins (LMWH) & Heparins
Unfractionated heparin (UFH) directly inhibits activated coagulation factors, (1) thrombin and (2) factor Xa. In low doses, heparin mainly targets Xa, in high doses heparin also thrombin. It works quickly, after intravenous administration within 20-60 minutes. Its effect is sustained over 12-24 hours. Heparin also (3) activates anti-thrombin (III) to a lesser extent. LMWHs contain heparin fragments with a lower molecular weight. The smaller fragments stick less to the arterial walls or proteins, which makes their effect a lot more predictable. LMWHs are 2-3 times more active against factor Xa than thrombin compared to UFH.
Things to look out for with heparin/LMWH use
Bleeding is a major concern with heparin and LMWHs, but heparin induced thrombocytopenia (HIT) can occur in rare cases. This is a life threatening syndrome, which develops within 5-15 days after exposure to heparin or LMWHs. The chances of developing HIT are lower with LMWH use than unfractionated heparin. HIT is diagnosed based on clinical symptoms such as fever, hypertension, tachycardia, shortness of breath and thrombotic events. In lab testing, you observe decreased platelet count. The heparin should be stopped and the patient should never receive UFH or LMWHs again, as a "cross-reaction" may occur. It is important to register this as a contra-indication. As an alternative, danaparoid of fondaparinux may be used as substitute fast-acting anticoagulants without eliciting HIT.
Click here to see how HIT develops
Measuring effectiveness
The activity of UFH is measured with an aPTT screening (do you remember what this value is with heparin use?). It is important to time this measurement well to get a good indication of the effect. When should the aPTT be measured with heparin use? Click on timeline below. apTT should be measured [...] after UFH initation
Because an LMWH mostly targets factor Xa, the effectiveness in therapeutic use is measured through anti-Xa activity screening. This is not always relevant to measure, only for certain patients. Which of the following factors does NOT require anti-Xa screening?
Obesity Decreased kidney function (< 30 ml/min) Liver disease Pregnancy Hypertension Neonates/children
The Tmax of heparins is roughly 4 hours. That's the best time to measure the aPTT.
7hr.
4hr.
1hr.
8hr.
9hr.
10hr.
5hr.
6hr.
2hr.
3hr.
Dosing UFH & LMWH
Heparin is dosed based on kg AND the aPTT, where adjustment of dosage may be necessary. That's why administrating heparin via pump is more convenient, as you can adjust the administration rate quickly.
LMWHs are dosed per weight-range. For nadroparin for example: 5700 IE for 60–69 kg, 4750 IE for 50-59 kg. In patients with obesity, it's not clear yet what the optimal dosing is; whether it should be capped or still dosed based on bodyweight. Anti-Xa screenings are also not accurate. So in obese patients, dosing LMWHs can be quite difficult.
UFH and LMWH are dosed based on weight and indication. For LMWH, kidney function is important as well, as it is excreted via the kidneys.
Protamine can be used as an antidote for UFH but is less effective against LMWHs (25-50% effective)
Both are used either intravenously or subcutaneously.
+ INFO
Considerations for anticoagulants
Certain things are important to consider when working with anticoagulants for Mr. Whitaker. Click on the (+) for more information about these different considerations for each anticoagulant group. Click on the (+) again to hide the Tooltip. After this, we wrap up the e-learning with 6 follow-up questions with Mr. Whitaker.
DOACs and VKAs are first choice to prevent and treat thrombo-embolic events. Nowadays, patients are almost always started on DOACs unless there's a contra-indication. Patients who use VKAs and react well to them are mostly kept on VKAs and are not necessarily switched to DOACs. LMWHs and heparin are used as prophylaxis of thrombo-embolic events, especially in cases where oral anticoagulants are not appropriate, for example right after surgeries, when anticoagulation is urgent, or in pregnancy.
Because DOACs have a set dose, it's more patient friendly. The frequent dose monitoring and dose adjustments of the VKA's make it less patient friendly. Because LMWHs/heparins are taken intravenously or subcutaneously, it's less patient friendly. That's why their use is limited to bridging in an outpatient setting.
For patients with an inconsistent lifestyle, DOACs are preferable. When it comes to polypharmacy, both VKAs and DOACs have many drug-interactions. That's why it's important to stay vigilant of a patient's medication list. For patients in unstable conditions or declining health, keeping an eye on their kidney function can be crucial, as DOAC dosage may have to be adjusted. DOACs may also not be used in patients with a mechanical heart valve.
DOACs generally don't require monitoring, whereas VKAs require regular monitoring of the INR to adjust dosage. LMWHs and heparin do not require routine monitoring for prophylactic doses, but may require monitoring at therapeutic doses. This is only the case with certain characteristics; in children, and patients with decreased kidney function, high BMI, or pregnancy.
DOACs have a similar (and possibly even lower) risk of bleeding compared to VKAs. With VKAs, however, these risks are easier to monitor when the INR gets too high. Both have their specific antidotes, where fytomenadion is cheaper than idarucizumab or andexanet alfa. LMWHs and heparins have a higher bleeding risk, especially in higher doses. That's why for therapeutic use with high doses, an intramural setting with controlled patient monitoring is more appropriate.
Follow-up with our patient
(1 of 2)
Mr. Whitaker's surgery
In a few days, our patient's surgery is planned. The orthopedic surgeon advises to discontinue his apixaban a few days before the procedure to minimize bleeding risks during surgery.
How many days before the scheduled knee replacement surgery should Mr. Whitaker discontinue his apixaban?
How many hours post surgery should he resume his apixaban to balance risk of thrombosis and bleeding?
5 days
3 days
1 day
48 hours
7 days
24 hours
1 hour
72 hours
Patients receiving an elective knee surgery on apixaban should always be bridged with an LMWH.
Which laboratory test is most appropriate for assessing bleeding risk pre-surgery (considering apixaban)?
INR
aPTT
PT
Anti-Xa
False
True
Follow-up with our patient
(2 of 2)
Mr. Whitaker's surgery
In a few days, our patient's surgery is planned. The orthopedic surgeon advises to discontinue his apixaban a few days before the procedure to minimize bleeding risks during surgery.
What key information should Mr. Whitaker receive regarding the resumption of apixaban after surgery?
In which of these scenario's would bridging therapy NOT be advisable for a patient with VKA use?
"Resume apixaban immediately after surgery to prevent blood clots."
The patient has a mechanical heart valve
"Wait until the surgical wound is completely healed before restarting apixaban."
The patient suffers from AF or a CHA2DS2VASc > 5
"Contact your healthcare provider if you experience unusual bleeding/bruising after restarting apixaban."
The patient has a decreased kidney function
"Take a higher dose of apixaban for the first week after surgery."
The patient had a stroke, episode of systemic emboli or VTA in the last 3 months
05
key messages per profession
Proceed for
Pharmacy | Nursing | Medicine
Anticoagulation | Pharmacy
Finish the e-learning
Anticoagulation | Pharmacy
Finish the e-learning
Anticoagulation | MEDICINE
Finish the e-learning
You've finished this e-learning!
We've gone through several aspects of anti-coagulation for the different professions. We will discuss your perceptions of roles and responsibilities in pharmacotherapy and work on a case-simulation in interprofessional groups. For this, do the following: 1) Reflect on these statements and bring you answers to the workgroup.
- How do you represent your health care profession in anticoagulation therapy?What are your responsibilities?
- How do you think other health care professions are involved in this process?
- What skills/competencies do you need to possess to participate in collaborative practice?
2) Download the app Team Up! Find Team Up! in the Google Play Store/App store or scan the QR codes below.Google Play Store
App Store
This is the right answer
Apixaban has bleedings as the most obvious side-effect. The key word here is unusual. Bruising occurs often, but when this becomes excessive, a healthcare provider must be informed.
This is the wrong answer
Knee surgeries have an intermediate risk of bleeding. For apixaban, cessation 1 day before surgery is the sufficient. Longer cessation increases the risk of thrombosis. In case the patient has a decreased kidney function, we should cessate apixaban 36 hours before surgery. Do you know why?
This is the wrong answer
Restarting apixaban immediately after surgery increases the bleeding risk. We have to postpone the restart for longer than 1 hour.
This is the right answer
Once a creatinine clearance below 30 ml/min is reached, the chances of dabigatran accumulation is greatly increased. In that case, dabigatran should be avoided. Of all DOACs, apixaban is cleared the least by the kidneys. So apixaban is the safest option for patients with kidney diseases.
This is the wrong answer
We aim to achieve a lower INR with VKAs. Multiple options may be correct.
Try to think based on the mechanism of action.
This is the wrong answer
When a patient is exposed to (1) heparin, it can bind to (2) platelet factor 4. This complex becomes immunogenic and attracts an (3) antibody, often IgG. The antigen-antibody complexes bind to platelets, leading to (4) platelet activation. This causes 2 important things:1. Release of prothrombotic (5) microparticles2. (6) Platelet consumptionThe platelet consumption leads to thrombocytopenia. The microparticles promote more thrombin production, which leads to thrombosis.You can find more information on HIT here.
This is the right answer
To avoid any VTEs due to his atrial afibrillation, restartin apixaban in time is important. This is 24 hours after his surgery.
This is the right answer
For patients with high-intensity therapy of VKAs, we strive to achieve an INR of 2.5-3.5. What range do we use for patients with low-intensity therapy?
This is the right answer
It can take about 2-3 days before optimal effect is reached. This is often bridged with a LMWH to make sure anticoagulation still takes place within these days.
When a VKA is switched to a DOAC, the DOAC should be administered only if the INR < 2 to reduce the risks of bleeding, because the effect of the VKA still lingers on. On the other hand, if a DOAC is to switched to a VKA, then the DOAC should be ceased until adequate INR > 2 is achieved. Because it take longer for VKA’s to be optimally effective.
This is the wrong answer
This is the wrong answer
Click on (X) to try again.
This is the wrong answer
Restarting apixaban 72 hours after surgery increases the risk of thrombosis as he won't be treated for his atrial afibrillation in time.
It takes some days before the optimal effect of VKAs is reached.
This is the wrong answer
This is the right answer
Other risk factors are a body weight < 60 kg and a serum creatinin > 133 µmol/L. When a patient has 2 of the 3 mentioned risk factors, the apixaban dosage should be halved.
This is the right answer
Fytomenadion is simply Vitamin K. Its maximal effect is reached after 24 hours, after which it's still active over 24-48 hours. That's why it's important to keep monitoring the INR for an extended period of time. Because fenprocoumon has a much longer halflife than acenocoumarol (160 hours vs 8-11 hours), there's a difference in follow-up time: 4 days for acenocoumarol, 2 weeks for fenprocomoun.
This is the wrong answer
Taking a higher dose for the first week applies to the therapeutic use of apixaban. In this case treatment goal is preventive: avoid a VTE due to his AF.
We aim to achieve a higher INR with VKAs. Multiple options may be correct.
This is the wrong answer
This is the wrong answer
When a VKA is switched to a DOAC, the DOAC should be administered only if the INR < 2 to reduce the risks of bleeding, because the effect of the VKA still lingers on. On the other hand, if a DOAC is to switched to a VKA, then the DOAC should be ceased until adequate INR > 2 is achieved. Because it take longer for VKA’s to be optimally effective.
Bridging with an LMWH is not indicated for DOAC use. This is because both medication groups have a similar T1/2. Bridging with an LMWH would give a similar effect as continuing the apixaban.
This is the right answer
This is the wrong answer
The healing process can take quite some time. If we restart only when it's healed, too much time has elapsed where the patient remains untreated for his AF.
This is the wrong answer
The optimal effect of VKAs takes some days to reach, but already occurs within a few days.
This is the right answer
When a VKA is switched to a DOAC, the DOAC should be administered only if the INR < 2, to reduce the risks of bleeding. When a DOAC is to switched to a VKA, then the DOAC should be ceased only when an adequate INR > 2 is achieved, to reduce risk of thrombosis.
This is the wrong answer
Idarucizumab is the antidote for a specfic DOAC and is not effective against VKAs.
This is the wrong answer
When a VKA is switched to a DOAC, the DOAC should be administered only if the INR < 2 to reduce the risks of bleeding, because the effect of the VKA still lingers on. On the other hand, if a DOAC is to switched to a VKA, then the DOAC should be ceased until adequate INR > 2 is achieved. Because it take longer for VKA’s to be optimally effective.
This is the wrong answer
The optimal effect of VKAs takes some days to reach, but already occurs within a few days.
Bridging with an LMWH is not indicated for DOAC use. This is because both medication groups have a similar T1/2. Bridging with an LMWH would give a similar effect as continuing the apixaban.
This is the wrong answer
This is the wrong answer
Click on (X) to try again.
This is the wrong answer
Restarting apixaban immediately after surgery increases the bleeding risk. We have to postpone the restart to 24 hours after surgery.
Click on (X) to try again.
This is the wrong answer
Decreased kidney function does not immediately put the patient in a risk group for increased thrombotic event occurence. Although it does affect the clearance of some anticoagulants.
This is the right answer
Andexanet Alfa is an antidote for certain DOACs, but is not effective as an antidote for VKAs.
This is the wrong answer
Apixaban inhibits factor Xa, so assessing with an anti-Xa screening is the most appropriate. However, this almost never done.
This is the right answer
Click on (X) to try again.
This is the wrong answer
This is the wrong answer
Click on (X) to try again.
This factor puts the patient in a risk group for the occurence of VTEs. In order to prevent these, bridging therapy is advised (but not for a DOAC with LMWHs as you've seen).
This is the wrong answer
This is the right answer
For patients with low-intensity therapy of VKAs, we strive to achieve an INR of 2.0-3.0. What range do we use for patients with high-intensity therapy?
This is the wrong answer
Click on (X) to try again.
This is the wrong answer
Knee surgeries have an intermediate risk of bleeding. For apixaban, cessation 1 day before surgery is the sufficient. Longer cessation increases the risk of thrombosis. In case the patient has a decreased kidney function, we should cessate apixaban 36 hours before surgery. Do you know why?
This is the wrong answer
Restarting apixaban 48 hours after surgery increases the risk of thrombosis as he won't be treated for his atrial afibrillation in time.
This is the right answer
Knee surgeries have an intermediate risk of bleeding. For apixaban, cessation 1 day before surgery is the sufficient. Longer cessation increases the risk of thrombosis. In case the patient has a decreased kidney function, we should cessate apixaban 36 hours before surgery. Do you know why?
This is the right answer
Cofact, also known as prothrombin complex, is a mix of different coagulation factors which have been inhibited by anticoagulants. The excessive depletion by VKA will be counteracted by supplying more factors. Cofact is a good option in case fytomenadion was not effective enough.