in this video we're going to talk about the basics of anticoagulation for residents and medical students this is going to be everything that you need to know to succeed on your Wards rotations and I'm also going to tell you how to choose between the various different anticoagulants that are available so let's get started the first thing that you need to note is that there are two kinds of anticoagulation goals so first of all you have a prophylactic anticoagulation and then secondly you have therapeutic anticoagulation or full dose anticoagulation is what I would kind of call this the reason I'm going over this is because this is a topic that is very simple but I did not understand uh you know actually when I was a beginning as an intern and I actually didn't know the difference between prophylactic and therapeutic anticoagulation so prophylactic is obviously as it's stated in the name you're trying to prevent a blood clot and therapeutic you are are treating a known blood clot already it's very useful to go over the different regimens that you have available so what do you have for prophylactic anticoagulation so one of the most common ones that you'll probably see is going to be Lovenox or an oxaparin 40 milligrams daily you may also see Lovenox 30 milligrams if they have an Aki so this is a reduced dose for their renal clearance another option is going to be heparin 5000 units Q8 hours or q12 hours if you think the patient is a high bleeding risk and then for obese patients what we typically do is going to be Lovenox 0.5 milligrams per kilogram daily so if a patient is 120 kilograms they're going to get a 60 milligram dose of Lovenox for example if they're also obese then you can do Heparin and what we do at my institution is usually 700 7500 units Q8 hours so this these are for obese patients and so how do you go about choosing this I would say number one we're always going to choose Lovenox 40 for a majority of patients but Heparin or Lovenox 30 milligrams really we're going to reserve that for patients with Aki for example because uh Heparin does not get really metabolized by the kidneys it's not going to get affected by it and so you know I prefer to do the Lovenox because it's just one once a day injection for the patients rather than three times a day injection like Heparin is so it's just a little bit more more pleasant for the patients rather than getting poked so many times so how do you decide whether a patient needs DVT prophylaxis in the hospital I will say as a medicine resident or on the medical service like 99 of your patients are all going to need DVT prophylaxis really it's only going to be those very extremely ambulatory patients that are not going to need DVT prophylaxis but just being in the hospital itself is a pretty big risk factor for developing dvts especially in our older patients because they definitely are not as mobile as normal and so they have an increased risk so I would say most patients should get DVT prophylaxis but if you are you know wanting to actually calculate something to see if they need it there is a padwa score for DVT prophylaxis so you can also check as well oh yeah and I forgot to add in that sequential compression devices are something else that we use for DVT prophylaxis you may also see them referred to as ipcs or intermittent pneumatic compression these are basically things that they place on the legs of the patient and they just intermittently squeeze or kind of Massage legs to try and prevent dvts the evidence for them is not super great but it is more than nothing right and if a patient particularly if they can't get DVT prophylaxis because they are um you know at risk of bleeding then giving an SCD is at least some kind of mechanical prophylaxis for dvts all right next let's talk about therapeutic anticoagulation and this is going to be uh basically a patient has a known DVT or PE and now we need to treat it with full anticoagulation or they have afib for example they need to be fully anticoagulated for that so therapeutic uh kind of one of our regimens for that so A big one that you're going to see is going to be a pixaban that's going to be five milligrams bid uh you're gonna see River rocksaband and that's going to be 20 milligrams daily you can see uh dabigatran 150 milligrams bid and this kind of really varies based on your uh formulary and so this is very popular at Kaiser but at my institution at UC Davis we don't really use this that much uh and then you've got things like Heparin drip and you're going to have Lovenox can go here as well but the dosing range for Lovenox is going to be different than the you know straight up 40 milligrams over here so um over on this side you're going to see that the dosing for Lovenox is going to be one milligram per kilogram bid and these are dosing regimens that are just going to be you're gonna have like memorized after a while uh or uh 1.5 milligrams per kilogram daily but uh usually you want to go for this one milligram per kilogram bid dose because there's less risk of bleeding and also it's better at preventing clots a couple of caveats here is that for a pixaban you actually have renal dosing so uh if your patient meets one of these three criteria uh age greater than 80. weight less than 60 kilograms or creatinine greater than 1.5 then you actually do 2.5 milligrams bid dosing for the decreased renal clearance that they're going to have and the other part I want to mention is that if somebody has a newly diagnosed DVT or PE you actually start them on kind of a loading dose of a pixaband beforehand so this is going to be uh 10 milligrams bid for seven days if new DBT or PE and this is the loading dose for River rocksaband the thing to know about this is you need to take it with food the absorption is not as good and also they have a loading dose as well if you have a new diagnosed DVT or PE and that's going to be 15 milligrams bid times 21 days does not really have a loading doses necessarily but they do recommend you do a five days of IV uh anticoagulation before you start the the bigotran and then for the Heparin drip uh one thing I like to ask Learners is what is the advantage of using a Heparin drip compared to all of these other things why do we often use Heparin drip in the hospital and the advantage is that it is fast on and fast off so basically when you turn it on the patient becomes anticoagulated very quickly but if they start bleeding or something or they have a procedure coming up you can immediately stop it and their anticoagulation will basically be gone you know within a few hours as well so that's one of the key advantages of a Heparin drip oh yeah and I just realized one thing I forgot to put here um on my prior lectures is that obviously we have Warfarin here or coumadin and so uh you know this is a vitamin K antagonist uh what what I'd like to say about this is usually you shouldn't try not to start people on Warfarin it requires frequent lab monitoring um and also you need to achieve like an INR goal of around two to three and then frequent lab monitoring it's just like it has so many drug drug interactions even if they change their diet slightly and they get more vitamin K in their diet from spinach or like vegetables or something it's gonna mess up their INR so ideally try to avoid Warfarin if possible all right one quick point that I wanted to touch upon but this is basically how do you really choose between a pixaban or Eliquis and River Rocks band or Xarelto this is a very common situation that comes up in the hospital I think with new Learners they're like why do we choose one Doak over the other and typically you'll see that I think a pixaban is really kind of the favorite one especially among cardiologists and a lot of people like I personally prefer a pixie man as well and let me just show you kind of why that reasoning is so if you imagine uh you know the big difference here is what it's basically the dosing regimen so a pixel man is twice a day whereas river oxman is only once a day so if I were to draw I really like to draw these graphs for people who are learning this or who I'm teaching so if I am going to graph you know their anticoagulation in over time in both of these so say the top graph is a pixaban and the bottom graph is Xarelto or riverox span with the twice daily dosing you're kind of going to get an anticoagulation level with a little Peak at the beginning and it's going to level off and then you get the second dose later in the day and so you kind of get this kind of a look for your anti-coagulation curve whereas for riveroxaban instead it's only a one time a day dose and so what you really get is this big spike early on and then it kind of levels down and then kind of just decreases throughout the day so what are the implications of this well for pixaban you just have so much more of a steady level of anticoagulation so what are the benefits of that you're going to have less thrombosis you're going to have less bleeding because there's no huge Spike and uh I mean those are the main two things that we worry about right less thrombosis and less bleeding that sounds great that's why you know most patients should probably be on a pixaban riveroxaban you know we do use this in some patients and why is that so look at this you have a huge Spike right there and then you have a lower level of anticoagulation throughout the day so the kind of consequences of that are you going to have increased risk for thrombosis because remember you have this whole period throughout the day where you're less anticoagulated than the apixavan group you have increased bleeding because you have this huge Spike right in the early beginning of the day but then the question is why would we ever give riverox man to anybody and the answer to this is going to be um it's it's easier uh easier to adhere to so imagine for your patients who have difficulty tolerating many medications they're non-compliant for some reason or they just you know have some other issues where it'd be more difficult for them to take a twice a day medication rivaroxamine is clearly going to be the better choice here because the Simplicity of a once a day medication May outweigh the risks of you know this increased thrombosis and increased bleeding because at least they'll be taking the medication rather than with the pixaban where they might be missing Doses and like stopping it all together or doing something like that so if anybody has an adherence or compliance issue then riverox band is one that you really want to consider in that situation all right and that's going to end this video on anticoagulation Basics and how to choose an anticoagulant in the next video we're going to be talking about DVT and PE so if you want to look here or here I'm not sure where I'm going to put it but I'm going to put a video here so we can talk about DBT PE diagnosis and treatment and how to really put into practice all of this information that we went over today in this video so I'll see you in that video thanks again for watching and peace