Managing Coumadin as a PCP: Case Study for Nurse Practitioners
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Show notes:
You're on call and you get paged about a critical INR...
You get a new patient from the ED who just started on coumadin for a DVT...
You're spending way too much time leafing through resources, trying to figure out when to draw their labs, how often, and how to adjust their dose...
If this sounds like you, this week's video has got you covered.
Managing Warfarin in Primary Care
How to know what dose to prescribe, when to adjust their doses and when to come back to the clinic
Whether a patient should go to an anti-coagulation clinic or be managed in-house
What to look for in patients with critical INRs, and when to send them to the ED
My favorite algorithms to make life easier.
PLUS! Another cheat sheet & dosing algorithm (two gems!) for you to download when you sign up below this video, all about Coumadin management to keep at your desk, so you don't have to worry about taking notes while listening.
Managing Warfarin Cheat Sheet
This episode comes with a cheat sheet to print out and keep at your desk for quick reference! Download your cheat sheet here.
-
0:02
so I'm gonna be talking about managing
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warfarin in primary care so if you're
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unsure how to manage patients on
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warfarin how to adjust their dosing how
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soon to be repeating their INR s and how
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often to bring them in if you panic when
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you get a critical INR result either in
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clinic or on call or if you wonder when
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to send patients to the IDI you're in
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the right place that's what we're gonna
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be talking about today so this is MP
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practice made simple I'm Liz Rohr I'm a
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family nurse practitioner and these are
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the weekly videos to help save you time
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frustration and help you learn faster so
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you can take the best care of your
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patients so before I get started I
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wanted to let you know I made a
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primary-care warfarin management cheat
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sheet so definitely download this below
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the video so you can follow along also
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you don't have to worry about taking any
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notes or anything I've really kind of
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summarized the the majority of what I'm
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talking about today with some other
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added bonuses in there including the
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algorithm that I super love it's
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actually two documents so when you sign
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up you'll see you'll see just sign up
0:54
and you'll get it but down below so this
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is Laura I'm gonna be doing a case study
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this is actually a patient that I did a
1:00
case study on a couple weeks back on
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hypercalcemia high calcium if you
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haven't watched that yet definitely go
1:05
check it out after this video but Laura
1:07
is a 36 year old female she's a new
1:09
patient and this is not her real name or
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her photo this is a recap of kind of the
Background
1:14
background if you've already watched
1:15
this or you watched it recently I can
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give you the timestamp below this video
1:18
where you can kind of shift ahead but
1:20
she's here to establish care she's a new
1:22
patient to the clinic she is coming from
1:24
the ER as a follow up for a DBT this is
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her first one she's ever had it's about
1:29
to about a week later from her ER visit
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so she's on an oxy print in an oxidant
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bridge until therapeutic with warfarin
1:35
with an INR goal of 2 to 3 and I'm gonna
1:37
talk about what that means so just stick
1:38
with me for a sec so she's a former
1:40
smoker smoking a half a pack a day and
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she just stopped
1:43
she's taking Queen Anne's lace up lament
1:46
for contraception this is her words she
1:48
it's an herbal over-the-counter
1:50
supplement that people can take and
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unfortunately doesn't have super great
1:53
traditional medicine evidence but what
1:56
kind of recap talking about that um her
1:58
past medical history is significant only
2:00
for therapeutic abortion a few years ago
2:02
she has no known past surgical history
2:05
and family history although she's not
2:07
like super sure about her family history
2:09
if there's any sort of bleeding problems
2:11
blood clots involved she's really just
2:13
can't say so and which I didn't mention
2:15
the last case study but I
2:16
remember that as I'm making that making
2:18
this one so sexually active with one
2:20
male partner and she's a working
2:22
professional she works at a bank Monday
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through Friday kind of a nine-to-five
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situation so the plan for her today I'm
2:28
going to be focusing on anticoagulation
2:30
using primarily the ACE the ACCP
2:33
guidelines which is the actually the
2:35
American College of Chest Physicians and
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also the real I trial which has a good
2:41
coumadin warfarin dosing protocol and
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this isn't for adults only a non
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pregnant adults actually and it doesn't
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include Pediatrics so please don't apply
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any of the stuff to those populations so
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at this visit I checked our labs her INR
2:54
for CBC and her CMP unfortunately I
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couldn't get access to the records from
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the hospital and she only had her
3:02
discharge paperwork for the like the
3:04
patient one which didn't have a ton of
3:05
information and I wanted to make sure I
3:07
had a baseline there so the results so
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her INR is 1.3 and actually in the last
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video her INR was therapeutic but for
3:14
the purposes of this presentation there
3:16
outside of range so outpatient warfarin
3:19
management and this is in the handout so
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don't worry about writing all this down
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but number one these are all the things
3:23
I kind of think about when I have a
3:25
patient who's on warfarin in front of me
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like what is their eye on our goal and
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I'll talk more about these each on the
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next slide what is the length of their
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therapy is it three months six months 12
3:34
months life time in house are we gonna
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be managing her in house or are you
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going to be referring out to an
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anticoagulation clinic what does her
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follow-up plan an educational plan and
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then assessing signs of bleeding I
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always throw this in with pretty much
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anybody who's on anticoagulation just
3:50
always asking in every visit or
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interaction that you have so initially
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when someone's first starting on
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warfarin typically I'm getting them out
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of the ER or the hospital and they've
4:00
already been started on this this
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regimen and then I'm kind of inheriting
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them and continuing on that's kind of
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the classic case that I found at least
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so I in our goals for the vast majority
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of people are between two and three
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however there are certain conditions
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specifically mechanical heart valves
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that are two and a half to three and a
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half this is very patient dependent and
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diagnosis specific so you also want to
4:22
determine again the length of therapy so
4:24
is it three months six months twelve
4:26
months our lifetime and the vast
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majority of people are going to do have
4:28
a minimum of three months of
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coagulation the reason this is important
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is that couple things number one this
4:35
this is highly individualized it's based
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on the history and the underlying
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conditions of the patient and it has to
4:40
do with a couple of things of whether or
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not the DVT was provoked or unprovoked
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meaning something kind of caused a
4:46
versus it happened on its own related to
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some underlying chronic condition or
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other blood clotting problem but also
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you want to make sure that I know that
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when I get I inherit new patients or
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when I started as a new nurse
4:58
practitioner I would get patients who
5:00
are on warfarin and I didn't
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automatically think like Oh should we be
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continuing this I always want you to
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think about that is like that tends to
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happen as patients get kind of get lost
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in the shuffle in some ways where they
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are on anticoagulation longer than they
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need to it doesn't happen often but just
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something to keep in mind like if you
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just want to be really intentional about
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the patients that are going to be on
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lifetime anticoagulation or long term if
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it's not lifetime and then management
5:21
you want to decide is this in-house
5:23
management or is it in an
5:25
anticoagulation clinic and so them the
5:28
most important thing I think is if even
5:30
if you feel comfortable following the
5:31
algorithms and knowing the management of
5:33
warfarin it's really important to have
5:35
some sort of nurse case management
5:36
support in a lot of ways because or some
5:38
sort of systematic clinic support so the
5:41
way that looks like is my clinic right
5:43
now has nurse visits where patients come
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in person to a rapid INR they have a
5:47
whole a kind of protocol worksheet that
5:48
is like signed off by a provider versus
5:51
is there a nurse case manager that has a
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list of all the patients that need to
5:54
follow up again and reaches out to them
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when they don't come back things like
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that I don't always have the luxury of
6:00
sending out to an anticoagulation clinic
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because of my patients a lot of my
6:04
patients have limited access to
6:05
resources so I do a lot of this myself
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but I also have that system systemic
6:09
support and then initiation so when some
6:11
of these being started on warfarin
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they're usually also started on a low
6:14
molecular weight heparin or heparin in
6:18
addition to warfarin until their INR is
6:19
therapeutic there are other
6:20
anticoagulation options that I'm really
6:22
focusing on warfarin today and once
6:25
their therapeutic for 24 - for 24 hours
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- for two days you can stop that low
6:29
molecular weight heparin or heparin
6:31
because again like well it takes about
6:34
three days to see a change so it's a
6:36
vitamin k antagonist so that's why
6:38
you're kind of on both and that's why
6:39
you want to wait until about 24 hours -
6:42
two days of being therapeutic - to come
6:44
change to take that off and I'm gonna
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introduce the two I just wanted to show
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you this picture cuz I'm gonna be
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referencing what I'm talking about
6:51
warfarin is adjusted based on dosing
6:53
algorithms and there's a number that are
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available this is the one that I use
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that I've used for the last four years
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and I find it to be extraordinarily
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helpful and very accurate and so
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literally what you're doing is looking
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at the target of whether it's two to two
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to three or two and a half to three and
7:07
a half and deciding if they have any
7:09
bleeding and just plugging in the number
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what you get and then going from there
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there's a little bit of nuance as you
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can see and I'm sorry this picture is a
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little bit blurry in the in the cheat
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sheet down below it's it's crisp crystal
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clear I promise and so these are these
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are nuanced because you can have a
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couple of different options but I'll
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kind of get into the decision-making
7:27
around that so continuing on so if they
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have if you've already been initiated
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you're continuing the INR you're gonna
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recheck the INR every three to eight
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days initially again using those
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algorithm based dosing not before three
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days typically because it doesn't really
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change it takes a little while to kind
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of catch up to any dose change so you
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can talk about it in terms of the daily
7:47
dose or the weekly dose so for example
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this patient is on five milligrams a day
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and they're her weekly dose is thirty
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five milligrams in total and so what I
7:55
mean by that is that it's really based
7:56
on the dose calculation that you're
7:58
doing that's convenient for the the
8:00
pills that are available the patient to
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take on a daily basis and for you to
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kind of make sure that it's an adequate
8:06
adjustment for them right and so I
8:08
really recommend trying to keep it as
8:09
simple as possible keeping the same dose
8:12
the same time or the same the same dose
8:14
every day instead of alternating doses
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if you can it doesn't always happen that
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way sometimes you have to to get the
8:20
therapeutic level but there's a couple
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different algorithms so that one that I
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referenced is from American family
8:24
physician American College of Chest
8:27
Physicians and the real I trial protocol
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have different ones as well it comes
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from and there's another note is that it
8:34
like I said it kind of comes in a
8:35
variety of doses so you want to think
8:37
about what is the most kind of helpful
8:39
for your dose that they need versus
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convenient for the patient
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etc etc so there's there's one memorize
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this you will if you do this a lot but
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it's one milligram two milligram two and
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a half three five seven and a half and
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ten are the typical ones that I've seen
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and it's usually a combination of
8:54
several for example the daily dose of
8:56
five milligrams is great because it's a
8:57
five
8:58
tablet but if you need to adjust by one
9:00
or a half you have to kind of add a
9:02
different dose to to that right so once
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it's therapeutic for a week so it's you
9:09
know the first time it's therapeutic you
9:10
check it again in a week so it's
9:12
therapeutic today at 2:00 you check it
9:14
next week and it's also 2 that means
9:16
that the next time you check it can be 2
9:17
weeks from the second one because it's
9:20
been therapy 2 for 2 weeks
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and then at the end of that if it's been
9:23
4 weeks in a row where it's still 2 you
9:25
can check it every 4 weeks after that
9:26
until it's stable
9:27
the ACCP you can says you can says you
9:29
can check it up to every 12 weeks if
9:31
they're stable I don't know if I feel
9:32
comfortable doing that myself but if
High INRs
9:35
that's that's an option available to you
9:37
so I want to talk about high INRs and
9:39
low inrs so again this really depends on
9:41
the number and bleeding and so if you
9:43
are anything like me you like step by
9:47
step very clear if this then this or
9:49
most new grads that I've actually I've
9:51
been talking to recently have the kind
9:52
of similar feeling right but this is not
9:55
as may be clear and step by step as you
9:57
probably like but I'm gonna do my best
9:59
so bleeding any bleeding with an INR
10:02
that's elevated they may or may not need
10:04
to go to the ER and this really depends
10:06
unfortunately on kind of categories of
10:08
minor and major bleeding and this is
10:10
really not super well defined but I've
10:11
come up with a list here of things you
10:13
want to think about so in terms of the
10:18
the main things that I've seen when
10:19
patients have bleeding with warfarin
10:21
management is that they have hematuria
10:24
most patients need to go to the ER with
10:26
heatin materia because they may need
10:27
bladder irrigation depending on the
10:28
clinical scenario but this is like gross
10:30
hematuria is what I'm talking about then
10:31
you want to kind of extrapolate to what
10:33
are the signs of like an internal bleed
10:34
right so any neurologic changes severe
10:37
headache intracranial bleeding right a
10:40
new abdominal pain especially severe and
10:43
especially anybody who has any sort of
10:44
injury or motor vehicle accident in
10:46
general they need to go to the ER if
10:47
their own anticoagulation but those are
10:50
all just kind of like the things to
10:51
think about you know possibly also like
10:53
so a lot of people want more on warfarin
10:55
get pretty big bruises but as long as
10:57
it's not like really severe enlarging
10:59
super painful kind of in the context of
11:01
an injury or something like that um and
11:03
and worst games worst case scenario you
11:05
send them to the ER the ER you give them
11:07
the alarm sign so they can self triage
11:09
right and then
11:10
gonna manage them according to the
11:11
algorithm of your choice and so this
11:14
involves holding doses decreasing the
11:16
total dose and then considering whether
11:18
or not to do vitamin K because then
11:20
began it's a vitamin k antagonist and so
11:23
if you give vitamin K back it's gonna
11:24
bring that INR back to the back down and
11:28
then you always want to review those
11:29
alarm signs for patients and so you kind
11:31
of just say the best you can blood in
11:32
your urine severe new pain bleeding
11:35
signs of bleeding that's not stopping
11:37
things like that because you know their
11:38
gums might be bleeding but people who
11:40
are not on more friend have bleeding
11:41
gums right so you just kind of paint the
Low INRs
11:44
clinical picture as best you can for
11:45
them so managing low INR s so single low
11:49
reading in a previously therapeutic INR
11:51
doesn't mean bridging so what I mean by
11:54
that is that when patients would would
11:55
drop below their therapeutic range they
11:57
used to automatically get added back on
11:59
either heparin or a low molecular weight
12:00
heparin and so a stable INR is
12:03
considered to be two or more consecutive
12:05
readings that have been normal you would
12:08
and the reason they kind of change that
12:09
is if there are more risks of bleeding
12:10
then there are benefits of avoiding
12:13
thrombosis so you want to consider
12:16
bridging that's what I mean by bridging
12:18
is like adding that back on with the
12:20
warfarin until the INR is normal or in
12:22
the right range that you're looking for
12:24
if it's continued to be sub therapeutics
12:26
under the level that you want it to be
12:28
for several readings or if they're a
12:30
high risk patient which is loosely
12:32
defined as having a venous
12:33
thromboembolism within three months
12:35
atrial fibrillation with a stroke in the
12:38
last three months or a mechanical heart
12:40
valve so going back to this algorithm
12:42
we're gonna reference this again comment
12:44
going back to Laura so for her it's safe
12:46
to do an outpatient management um
12:47
whenever it's low you always want to
12:49
assess the adherence for somebody when
12:50
their INR is a 1.3 then thinking again
12:53
about medications that it may interact
12:55
with it and dietary changes I'm sure you
12:58
learned about the diet in school in
12:59
terms of the warfarin and what dietary
13:01
management to do for that there's a huge
13:03
laundry list of medications that can
13:04
interact and you kind of just want to
13:05
always ask about over-the-counter
13:07
supplements run those kind of
13:08
interaction reports with the medications
13:10
of patients currently on and then decide
13:13
if that's kind of a factor and I talked
13:15
a little bit about that in the cheat
13:16
sheet as well how to manage that so
13:19
increasing so based on this algorithm
13:21
that I that works really well for me
13:23
she's in this
13:24
less than 1.5 range and so you have the
13:27
option of either increasing by 10% 20%
13:29
or adding an extra dose and so those
13:31
options are increasing to 5.5 a day six
13:34
milligrams a day plus or minus adding an
13:36
extra five milligrams and so my thought
13:38
process behind that is that she's not
13:40
that far from 1.5 she's not 1 she's not
13:42
1.1 and I also want to choose a
13:44
convenient dose for her rate and so I'm
13:47
gonna actually go with the 20% the
13:48
higher dosing because it's six
13:49
milligrams cuz that's only two pills
13:51
versus adding an extra dose like I may
13:53
probably do that if she was lower than
13:57
that but again every patient is so
13:59
different it's really hard to know so
14:00
what you do is you just check it again
14:02
the next week and so again you can
14:05
recheck it in a week or you if you were
14:07
being a little bit more aggressive in
14:09
terms of trying to get her off the low
14:10
molecular weight heparin and stay on the
14:12
warfarin you could check every four days
14:14
but again it's kind of patient-centered
14:15
like is she gonna be able to come back
14:16
that often things like that and so I
14:19
left this on here the two scenarios so
14:22
this patient is currently on a low
14:23
molecular weight heparin still the
14:25
anoxic runs she'd this just happened but
14:27
if this was a patient who recently had a
14:29
DVT say this was like a month from now
14:31
and she had her DVT less than three
14:34
months ago and she was already off of
14:35
that bridge
14:36
she was already off of the low molecular
14:37
weight heparin the anoxic room you would
14:40
consider adding that back on because she
14:41
was in that threshold a period of time
14:43
and hopefully she would have had them
14:45
extra low molecular weight heparins at
14:47
home the amounts are print at home
14:48
because I've found unfortunately is that
14:51
a lot of patients need a prior
14:52
authorization for their insurance to
14:53
actually get this covered so it can be a
14:56
challenge to get those bridged when you
14:58
need them and again you always want to
15:00
assess the need for duration of therapy
15:02
again because like when I was a new
15:04
nurse practitioner or when I change jobs
15:06
and I inherited new patients or I
15:07
whenever new patients came to the clinic
15:09
I would look and see that they were in
15:10
warfarin and I think it's really easy to
15:12
get sucked into a trap of like oh this
15:14
patient's on warfarin I'm just gonna
15:15
adjust them versus having really
15:17
thoughtful consideration of should I
15:19
continue them do they need to be on life
15:21
long is it three months six months 12
15:23
months ago you know etc etc so some
Alternate Scenarios
15:26
alternate scenarios excuse me alternate
15:31
scenarios here if her INR is 1.9 you
15:34
want to continue the same dose and
15:37
recheck it in a
15:38
because it's really not that far outside
15:39
the range and I found that most of the
15:42
time they'll go back into range excuse
15:45
me so her INR is three point four INR
15:48
was three point one you want to continue
15:49
that same dose again and recheck in a
15:51
week because it's really just point one
15:52
off so for example of her INR was four
15:55
though you'd go back to that algorithm
15:56
which gives you the option of holding
15:58
from zero to one dose decreasing by 10%
16:01
and rechecking in a week four to eight
16:02
days but about a week and then your
16:05
decision-making around that is like is
16:07
she in I forgot to mention this it's in
16:09
the cheat sheet as well there are
16:10
certain populations that are higher risk
16:12
for bleeding and so you want to start
16:13
with the lower doses for them and so
16:15
that may influence your decision-making
16:16
about where to go I mean I'm trying not
16:18
to make I may be making this too
16:20
complicated but you really just kind of
16:22
have to pick one choose it hopefully
16:24
they'll come back on schedule as
16:26
directed and then you can just make
16:28
adjustments from there and just looking
16:29
at the pattern over time where the last
16:31
three readings going up up up where they
16:33
going down or were they just all over
16:34
the place you know excuse me so if the
16:38
INR is more than five you're going to
16:40
assess for signs of significant bleeding
16:42
which again like just do your best like
16:45
on the bases on the things that I told
16:46
you you're gonna hold a dose decreased
16:49
by 10 to 20 percent rechecking in about
16:51
three days you could consider checking
16:53
it sooner if you're worried about it
16:55
increasing but if you're worried
16:57
somebody accidentally took a whole bunch
16:58
of warfarin they really should be
16:59
evaluated in the ER not an outpatient
17:01
and then you want to restart it when
17:04
it's once the INR becomes therapeutic
17:06
considering vitamin K times 1 that's the
17:08
ACCP guidelines of 2.5 to five
17:10
milligrams P o times 1 if their eye on R
17:13
is greater than 10 so going back to
Summary
17:15
Laura
17:16
so she's 36 she's a new patient again
17:19
she I referred her to endocrine again
17:21
going back to that presentation if you
17:23
haven't watched it already about
17:24
hypercalcemia so interesting so if if
17:29
she was outside of that week of if it
17:32
was so I left this on here but if this
17:34
was 2 months later after her year visit
17:36
I would restart the lovenox because her
17:38
INR sub-therapeutic and she was in that
17:40
3 month window versus she's still
17:42
continuing on it because she's only been
17:44
up for about a week so
17:46
continuing lovenox continuing warfarin
17:48
repeating the INR and four to seven days
17:52
smoking cessation again reinforcing that
17:55
that's super important to avoid future
17:56
DBT is contraception is super important
17:59
not only for just general herd general
18:02
life desires of not wanting to be
18:04
pregnant but also because warfarin is a
18:06
teratogen and so that's something I
18:07
really think about and then I did the
18:10
hematology referral for her because I
18:11
wasn't sure if it was provoked or
18:13
unprovoked and I was really worried
18:14
about her underlying possible
18:16
excuse me family history so I felt like
18:19
that was important and I just was
18:21
nervous and so I was like you know what
18:22
someone someone else helped me decide if
18:24
this is only for three months or not or
18:26
if this is a provoked one or if she
18:27
needs more long-standing further workout
18:29
things like that and I hadn't follow up
18:31
with me in about a month because I
18:32
wanted to make sure that her hematology
18:35
equipment was all set up and she was
18:36
doing well also this was kind of a big
18:38
change I just want to make sure she felt
18:39
okay and then we did just did every
18:41
three months until this whole thing
18:42
resolved and then we went back to annual
18:44
because she really didn't have a ton
18:45
going on in terms of chronic care
18:47
management so this is so that's it did
18:49
you like this video if so hit like and
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subscribe especially if you're on
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youtube and share with your MP friends
18:56
so together we can reach as many new
18:57
grads as possible to help make their
18:59
first years a little bit easier and if
19:00
you download that primary care warfarin
19:03
cheat sheet below this video you'll also
19:05
get the ultimate resource guide for the
19:07
new NP and you'll get these videos sent
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straight to your inbox every week with
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you know quote patient stories extra
19:14
bonus content but I really just don't
19:15
share anywhere else thank you so much
19:17
again for watching hang in there and
19:19
I'll see you soon
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