Bridging for the first time.

[marc_kowal]

Sooo on the 26th of this month, I'm having my first colonoscopy performed (yah for me!), and will be bridging for the first time. I received my instructions from my cardiologists office yesterday, and wanted some input from people who have done this before. Just wanted to know if this was similar to what you did, or if something seems wacky.

7/21- STOP coumadin
7/22- NO Lovenox
7/23- Lovenox in the AM and PM
7/24- Lovenox in the AM and PM
7/25- NO Lovenox. Go to hospital for Blood Draw to check INR
7/26- Day of Procedure, NO Lovenox. Restart douible dose of Coumadin (normal is 4.5mgs, so double dose is 9 mgs) in the evening IF no biopsies or polyps removed. (If that is the case, cardiologist will adjust remaining instructions.)
7/27- NO Lovenox, Double dose of Coumadin
7/28- NO Lovenox, Double dose of Coumadin
7/29- NO Lovenox, Regular dose of Coumadin
7/30- Go to hospital for Blood Draw to check INR. Cardio will contact me with Coumadin instructions for this day

I was told to get a blood draw since the Lovenox could affect my home test results.

Thanks for the input!

~Marc

 

[Protimenow]

I've never had a colonoscopy, so I'm not sure about how this differs from the instructions for a procedure like I had (cardiac catheterization). For me, I continued on Lovenox for a day or two after the procedure, while also taking warfarin.

In the case of a colonoscopy, perhaps they're concerned that even if they didn't diagnose anything or remove polyps, they may still be concerned that they may have nicked something during the procedure and don't want it to bleed while it's healing. That's the probable reason why they aren't bridging.

It takes two or so days for the effects of the warfarin to fully manifest. A double dose should bring the INR back into target range more rapidly than just taking your single dose - in theory, this will bring your INR back, but reduce the risk of intestinal bleeding that could be exacerbated by Lovenox.

Although, from the perspective of a cardiac cath, with bridging continuing for a day or two, your instructions seem to be a bit out of line, from the standpoint of possible secondary bleeding as a result of a colonoscopy, your doctor's instructions seem to make a lot of sense. If you've got concerns, ask the doctor.

FWIW - if your INR is below 2 or so, it can take a week or so in the unanticoagulated state before clots form on your valve(s), so a few days at sub-optimal INR should be fairly low risk. But, of course, if you have any questions, it probably wouldn't hurt to check with your doctor.

It would be good, too, if those of us who've been through the procedure give their experiences (which is why you asked this in the first place).

 

[pellicle]

I disagree with the double doses

 

[LondonAndy]

Forgive my ignorance - I have not yet had any surgical procedures since AVR 2 years ago - but from what I have seen so far I had expected the post-op restoration of anti-coagulation level to be achieved with injections of Heparin to rapidly 'thin the blood' (sorry Pellicle!) whilst Warfarin/Coumadin takes it's 3 days to take effect in the blood stream?

 

[KEN P]

KEN P
Am in the process now of having colonoscopy and bridging as follows
July 7th stopped Coumadin
July 8th started Lovenox injections twice daily
July 10th admitted to hospital day before procedure where they started Heparin IV then stopped it at midnight
July 11th 6am started a antibiotic. IV one hour before my Colonoscopy then restarted Heparin drip 6 hours after Colonoscopy and administered 10 mg of Coumadin continuing on that dose and decreasingHeparin IV daily until bridging is complete when INR reaches 3.0
July

 

[Protimenow]

What was your previous 'normal' dose of warfarin? If you're doing a double dose each day until your INR is 3.0, you may wind up with a way too high INR while warfarin's effects continue. I would self-test daily, taking my normal dose after the second day, and stop bridging once the INR is where you want it to be. (In fact, in my case, the night after my procedure, I took a 1.5 dose, then dropped to my usual dose and just kept a daily eye on my INR until it was back into range. Once I was in range, I stopped the Lovenox).

 

[pellicle]

Hi

... I have not yet had any surgical procedures since AVR 2 years ago - but from what I have seen so far I had expected the post-op restoration of anti-coagulation level to be achieved with injections of Heparin to rapidly 'thin the blood' (sorry Pellicle!) whilst Warfarin/Coumadin takes it's 3 days to take effect in the blood stream?

well in Australia at least the jury is out on the efficacy of bridging and indeed if it may not do anything at all for patients who are low risk (which would be bileaflet AVR patients with no history of AF). There are views in either camp (no bridge / bridge) and the best article I've read says that it will only be fully resolved by a proper study.

https://www.nps.org.au/australian-pr...nticoagulation

Do the benefits of anticoagulation outweigh the risks?
The approach to the management of anticoagulation in patients with prosthetic valves undergoing non-cardiac surgery remains controversial. The need for perioperative anticoagulation in patients with mechanical heart valves has been questioned in a recent review. The authors argue that for every 10 000 patients with mechanical heart valves who are given perioperative intravenous heparin, three thromboembolic events are prevented at the cost of 300 major postoperative bleeding episodes.3 These figures are calculated by assuming an average thromboembolic rate of 8% per year in patients with mechanical heart valves, an anticoagulation-free period of four days and a 3% risk of major postoperative bleeding with intravenous heparin. In light of these calculations, a risk-benefit analysis would preclude the use of full dose anticoagulation during the perioperative period in patients with mechanical valves, except in patients with very recent arterial embolism who have a high risk of recurrence in the absence of anticoagulation. In the absence of recent embolism, the authors recommend, for hospitalised patients, the use of subcutaneous low dose unfractionated or low molecular weight heparin at doses used forprophylaxis against venous thromboembolism, with no prophylaxis for outpatients.

What to do
The lack of adequate data makes it difficult to give firm recommendations. Patients on warfarin for tissuevalves (usually mitral) are usually managed preoperatively by cessation of their warfarin without heparin replacement. ... The final decision should take into account individual patient factors such as the surgical procedure, the type and location of the prosthetic valve and whether or not there are other indications for anticoagulation.

[bold + underline mine]
as I've written recently the need to stop bleeding may outweigh the potential risk of clots. I think there is a lot of scope to reevaluate our practices away from the "avoid a clot at all costs" when the risk of clot may be lower than the risks of bleeding (which can include infection in a wound that does not properly close).

When recommencing anticoagulation I have found that for myself that INR rose rapidly when I recommenced my dose. On my last debridement surgery (with extensive wounding by definition) I did not bridge and commenced soon after surgery.

Excuse the mess of the "model" in this chart, but the line shows I missed two days of dose and the green is my actual measured INR

To make that graph clear, there was no dose on day 3 4 and 5, day 6 resumed dose ( INR on LH axis dose inmg in RH axis) so it went up quickly.

 

[KEN P]

Well I disagree because this is the second time I've had a colonoscopy in four years and in both cases it took along time at double dosing to bring my INR back up to 3.0

 

[pellicle]

Well I disagree because this is the second time I've had a colonoscopy in four years and in both cases it took along time at double dosing to bring my INR back up to 3.0

good feedback

this iterates that "guidelines" are one thing, but as one size does not fit all that a known history, monitoring and decisions on a case by case are likely to yeild the best outcomes.

thanks for raising this aspect.

out of interest, why did you want your INR to be up to 3 which is close to "out of range"?

I had a quick look at your bio and wonder about why you are managed to an INR = 3 when that is the upper limit of the normal Aortic Valve guideline (which is commonly 2 ~3 in range), do you have other complicating factors?

just curiuos

 

[LondonAndy]

out of interest, why did you want your INR to be up to 3 which is close to "out of range"?

I had a quick look at your bio and wonder about why you are managed to an INR = 3 when that is the upper limit of the normal Aortic Valve guideline (which is commonly 2 ~3 in range), do you have other complicating factors?

just curiuos

Just to mention, the therapeutic range they specified for me with a mechanical valve is 2.5 to 3.5, so I aim for 3.0 too.

 

[pellicle]

Just to mention, the therapeutic range they specified for me with a mechanical valve is 2.5 to 3.5, so I aim for 3.0 too.

interesting ... did they say why?

do you have other risk factors?

seem to fly in the face of the current movement downwards in INR with studies suggesting that plain Aortic Valve patients on mechanical valves are safe at 2.0

from the GELIA study:

we conclude that low-intensity anticoagulation with a target INR of 2.0 to 3.5 is safe for patients with SJM prostheses in the aortic position as well as the mitral position

none the less its curious why they were continuing heparin when he was over the lower threshold of AC levels

 

[LondonAndy]

Sadly Pellicle I didn't think to ask why my INR therapeutic range was higher. I ended up having my AVR as something of an emergency procedure after what I thought was a heart attack but apparently was a "cardiac event", and so have done most of my research AFTER surgery! I keep meaning to ask what valve I actually have! Although I was shown one pre-surgery, and so I know it is a bi-flap thingy, if they mentioned the make and model I did not take it in, and I certainly wasn't aware of what the typical therapeutic range is. Will ask why at my next annual checkup

At a follow-up appointment with a different Cardiologist, he did say that my surgeon preferred a higher INR range to other surgeons, and as my guy apparently was the only non-American to gain some prestigious award when he studied in the States for a few years I have been content not to question it. But would be good to know reasoning, and whether a lower INR is ok. I am not aware of other cardio-vascular risk factors that might have influenced his decision.

 

[pellicle]

Hi

I didn't think to ask why my INR therapeutic range was higher. ... At a follow-up appointment with a different Cardiologist, he did say that my surgeon preferred a higher INR range to other surgeons... But would be good to know reasoning, and whether a lower INR is ok. I am not aware of other cardio-vascular risk factors that might have influenced his decision.

it matters not where you start or end, its the journey that matters

His reasons may be nothing more than a personal feeling that somehow higher was better for his patients.

To my mind an excellent test is to consider lowering it, then have a d-dimer blood test done to see if there are elements / fragments of thrombosis to be found. This will indicate if there is a thrombosis risk caused by your valve.

If you have (as you say) a bi flap thinggy and it was black in color, almost metalic in sound then you've got a modern bileaflet valve and thus the GELIA study relates to your situation (either St Jude, ATS/Medtronic or On-X, but in the UK probably one of the other two in order of probability).

Have you read it? If you can't download it PM me and I'll email you a copy

and so have done most of my research AFTER surgery!

I would say I'm exactly the same. When my Aneurysm was identified I was beginning to be aware of the need for a "checkup" because I'd simply stopped having them about 10 years before that. When I had my Homograft in 1992 I knew nothing much then either as 1) I was 28 and 2) I wasn't really concerned because in my life before the surgery had gone well and the Drs were way more informed than I could hope to be.

It was only after my wife passed away and I began researching how to manage my own INR (because I was irritated with the Clinic and I had this Coaguchek sitting around) that I learned what I have.

 

[marc_kowal]

After going back and forth with my doctor's office and expressing my concerns about not being "protected" for so long after my procedure, they agreed to have me on Lovenox until my INR is back in my normal range of 2.5 - 3.5. They also moved my Blood Draw to the 29th since the 30th is a Saturday and their office is closed.

Thanks for the input everyone, and I'll let you know how it turns out.

 

[Protimenow]

When I got my St. Jude implanted just short of 25 years ago, I was given (or mailed) a card that I keep in my wallet, identifying the valve, and also stating that I can have an MRI without concerns that the magnetic fields would bother the valve.

My last anticoagulation clinic used two different target ranges - one for 'one valvers' and a higher range for 'two valvers.' Having just one valve, they seemed to be comfortable with a range of 2.0-3.0. My current clinic wants 2.5-3.5.

It's interesting to see new thinking about bridging for non-cardiac procedures. I've had my INR, at times, around 2.0 - but I would never knowingly let it stay below 2.0 for any more than a day or two.

 

[marc_kowal]

So I had my colonoscopy yesterday, and when they did my blood work the previous morning, my INR was at 1.2. Last night I resumed the Lovenox injections and took a double dose of my Warfarin (9 mgs total). I'll keep doing the shots and double dose of warfarin until my blood draw on Friday and then the doctor will adjust from there. It'll be interesting to see how quickly my INR goes back up. BTW, got a clean bill of health from the exam, so I won't have to do this again for 10 years hopefully.

~Marc

 

[pellicle]

Hey Marc

glad the results were good ... just be careful that you don't overshoot the mark and then take longer to come back down again with those double doses. My opinion (which I know you don't care for but I'm writing for other readers) is to do a single double dose and then resume your normal dose. I feel you'll be in range with no overshoots just as quickly.

 

[marc_kowal]

My opinion (which I know you don't care for but I'm writing for other readers).

Not sure why you think I feel that way about your opinion, I don't believe we've even gotten into a debate about anything in the past.

I listen to any and all opinions, and then I use my best judgement to act or not act on those opinions.

No bad feelings on this end mate.

 

[pellicle]

Not sure why you think I feel that way about your opinion,

sorry Marc, probably my reading between the lines in the past when I've had my negative / depressed glasses on ... I keep looking around for my sunny ones, can't seem to find them quite frequently.

I don't believe we've even gotten into a debate about anything in the past.

I don't mind debate ... none the less its clear I got confused.

sorry about that

 

[Protimenow]

I just took another look at Pellicle's graph, and the left axis looked a bit odd to me. It looked to me as if your INR on days 5, 6 and 7 was 0.0 - a definite impossibility. Am I reading this correctly?