video demo - how I get enough blood regularly

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pellicle

Professional Dingbat, Guru and Merkintologist
Joined
Nov 4, 2012
Messages
13,081
Location
Queensland, OzTrayLeeYa
Hi

well I thought I'd put this together to (perhaps) help others here who may struggle with getting enough blood for their INR tests. Since today is Saturday (and thats my regular weekly testing time) I thought I'd set up my camera and show how I do it with my rubber band tourniquet / pressure bandage type technique.

I've moved on from the dental floss as the rubber band allows me to get a much more even pressure and better yet, when I just release it it unwinds for me.

note: wind the band down the finger not just around the point you started. I realise I didn't make that point clearly in the video. 3 or 4 turns is all thats needed and with respect to pressure: you don't need to work on cutting your finger off, just trapping the blood for a short time.

So, without further adieu ... the video

[ link ]


So even with stage fright (I dislike being in front of the camera and panic that I'd make a mistake [didn't want to do another take]) causing some vaso-constriction I still got a good sample this chilly early Finland spring day.

Basically no milking needed, often just a bend of the finger will have a blood drop form and be a "full hanging drop".

As you see it all happens quickly.

To recap on a previous post you should aim to:
* get more than enough sample (to avoid Error 5 and wasting a strip)
* do everything consistently
* follow the 15 second rule (and preferably keep time between beep and application of blood consistent too)

Using the approach my incidence of variance between the lab and my tests were consistently down to INR within 0.1

I found that getting the blood samples was harder in winter than in summer and (interestingly) harder when I was anxious about getting enough blood (probably vaso-constriction). Annoyingly the prick would often bleed more after I'd got my drop (or the error 5 as the case may be).

My method now is 100% at getting a good blood sample with minimal interference and in short order; I haven't wasted a strip in ages.


1) when the machine goes beep I wind on a rubber band (square section about 5 inches in diameter) starting at the first joint out from the knuckle and working towards the fingertip. I do not apply massive strech to the rubber-band but it is not loose either. You will soon see blood gathering in the fingertip. (you can practice this without lancing too)

2) when I lance I prick the side of the finger (and so far I have been reusing my lancelets for at least 3 months)
9431706361_e8bc3b48b9_n.jpg


There are a few reasons for the side:
- ask a diabetic, over time pricking the same place you damage the nerves, doing the side minimises the effect of that
- it hurts less
- the skin is thinner and so the lance does not need to be as deep
- if you need to do work later it won't be as annoying there

3) a gentle squeeze of the finger (often bending it even is enough) with the rubber band still in place gets the blood out in a matter of one or two seconds.

Lastly I notice that the latest PDF version of the userguide from Roche now is less cautious about "milking" the finger than my printed copy was. Further it has now included instructions on obtaining vein blood and using the coaguchek. So clearly their testing has revealed that the meter is less sensitive to the tissue factors that lay under the skin that some users have commented make a big difference. It seems they do not with the Coaguchek.

I do this every Saturday morning (you can pick your time) and then I write it up in my spreadsheet in a Dropbox folder (so its backed up off site, Google docs is another good spot). The whole thing takes 10 minutes from reaching for the Coaguchek and my coffee doesn't even go cold.

Hope that Helps

Best Wishes and have a good weekend

:)
 
A good educational video, Pellicle! Although I am not currently taking coumadin, I am always interested in learning about it's use. It takes away the unknown.
 
Really great video Pellicle thanks for posting! Like Ottagal, I'm not on coumaden either but I do appreciate knowing about these things and you've consistantly done a great job in educating others - thanks!
 
Hi I found this video instructive. Sometimes Alice and I waste a strip even after a lot of milking. We use the Tenderlett lancet which seems to take a shallow slice and not hurt as much as the Softclix. The rubber band is a great idea. Going to try it!
 
I had trouble getting a good drop once. After two tries, I took the cap off the device and stuck myself directly with the needle, all the way in. Worked great. I do that each time now and have never had another failure.

You may want to make sure using a tourniquet is an acceptable technique. During training, I was told not to manipulate the finger too much and to let warm water and gravity do the trick and not to squeeze the finger. Squeezing the finger is essentially what you do with the tourniquet.
 
I had trouble getting a good drop once. After two tries, I took the cap off the device and stuck myself directly with the needle, all the way in. Worked great. I do that each time now and have never had another failure.

that's the spirit!!

This came to mind immediately: The struggles of ACT patients to get blood flowing:

[ link ]


One ties his fingers while the other stabs himself ... :-D

I always found it ironic that on anticoagulation drugs I struggle to get a blood sample while people not on it tell me they're afraid of bleeding to death ... [shrug]

You may want to make sure using a tourniquet is an acceptable technique. During training, I was told not to manipulate the finger too much and to let warm water and gravity do the trick and not to squeeze the finger. Squeezing the finger is essentially what you do with the tourniquet.

Good point, yes, I am aware of that and was initially cautious myself. But if you read the current literature they even seem to discuss massage while in my older guide they were emphatic to not do that. For instance:

13854286175_190c468489_o.jpg


In my view of things the pressure band (again I emphasize not too tight) should do less to disturb subcutaneous tissue factors than all the massaging.

It seems that it has made little real difference to the readings except make them closer to labs... especially when since doing this I've got consistently the closest results to the vein test.

I tried to make the point that you don't tie it off like you're trying cut through, but wind on a gentle but firm pressure.

Naturally if you don't feel comfortable do it then by all means don't :)
 
I was told to soak my hand in warm water as well. However I am not patient, that's why I removed the lid and use the full 5mm length of the needle. The prick is not as painful as thinking about it :)

A phlobotomist uses a turniquet to find a vein, but samples with it released for an unobstructed flow. Using a turniquet is applying a constant pressure and restricting the blood flow, while "milking" is pressure/release phenomena and the sample is obtained w/o pressure. Using the turniquet in the manner described, you take the blood sample with the turniquet on and the flow constricted. My trainer specifically warned me about applying too much pressure saying to "milk" not "squeeze" out the drop. Although she did not say why and I did not think to ask. If a turniquet was an acceptable method it should be in the instructions.
 
All I can say is if you are interested and worried it may effect a result: try your normal way, try this way and if the numbers match then its not a problem.

The earlier manuals went on about needing really only the first drops of blood, now the same strips work on canulated blood too. On another forum a nurse tried drop, canulated blood and canulated blood left in the syringe for some 5 minutes. All numbers identical.

But like I say , if you don't like the technique don't use it.
 
"All I can say is if you are interested and worried it may effect a result: try your normal way, try this way and if the numbers match then its not a problem."

A turniquet is an obvious solution to insufficient blood sample for testing. When my device's supplier called to find out why it took three strips for one test. I complained about insufficient blood. They did not suggest a turniquet, they suggested warm water soak and sent me a sticker that made a bigger hole. I just went a little deeper with my existing small corer :)

I know a little bit about medical device development. One test by one person at one time is not sufficient information for the FDA to allow the instructions for a medical device to be modified by the manufacturer. It takes a trial and comparison of results.

Personally, I believe it is an inherently unsafe practice to not follow the instructions provided with the device.
 
I'm still learning, but slowly getting better. My protocol:

- Get meter and strip out.
- Wash and dry both hands
- Run hot water over left hand ring finger for maybe 30 seconds. As hot as I can stand.
- Insert strip
- Put rubber band around finger just above my wedding band.
- Hang left hand down my side vertically.
- When the meter 'dings', lance and (hopefully) get a good drop.
- Leave finger in place with drop on top. Pick up meter and stick the side of the strip into the drop. This has helped me from 'missing' the sweet spot on the strip.



-
 
Big_L -- I'd be concerned about moving the meter after getting that drop of blood. I don't know which meter you use, but some have specific instructions NOT to move the meter after you apply the blood to the strip.

Although I have, in the past, had success with the warm water and a 21 gauge lancet set to maximum depth, I've been using Unistik 3 Extra lancing devices (about 25 cents each on Ebay) and usually get a good drop every time.

One thing that I accidentally found worked as great prep (and women can ignore this one) is to test your blood right after you finish shaving. Exposure to the warm water, and movement of the hands while shaving (wetting the face, moving the razor, etc.) seemed to create an ideal condition for getting a good drop.
 
Hi Tom

I think you have raised very valid points and I believe that I owe it to any readers to address them properly, not just dismiss or ignore them.

... I am not patient, that's why I removed the lid and use the full 5mm length of the needle. The prick is not as painful as thinking about it :)


understood ... I hope you have not read into my reply any negative criticism of your method. I was just sharing that I was amused by a view that came to mind.


Using a turniquet is applying a constant pressure and restricting the blood flow,

well, not really much pressure and the pressure is well the sample point from blood flow terms so I seriously doubt that such hydraulic pressure changes will effect anything down stream. Also it is important to not wind tightly and not have the finger 'throbbing'. I would hope that people observed that in the video, but its a point that deserves to be made.

You'll notice from the video that my process is VERY fast. From winding on the rubber band (and again I stress not so tightly) to completion of application of blood drop is under 15 seconds. I would think that such a point is of much greater significance than the rubber band technique I have described.

Considering that the clotting factors WILL be activated by the skin breach and recalling that Roche stress again and again and again in their manuals about the 15 second rule:

13909866921_73858c00b9_o.jpg


Look carefully through that list and ensure that you are adhering to all of them (I suspect people often violate the temperature and humidity aspects). I recall that about a year ago I surprised a few people here with the 15 Second rule which people did not know of and peraps were not adhering to in getting their sample.

I notice that "milk the finger" is not on the Never list.


as you say
while "milking" is pressure/release phenomena and the sample is obtained w/o pressure.

except that the pressure created by massage, which I substantially doubt will be of any greater significance than the pressure I applied using the rubber band to cause gathering of the blood.

I think its also good to examine some of the issues that will effect clotting, For example(ref):
Platelet activation

When the endothelium is damaged, the normally isolated, underlying collagen is exposed to circulating platelets, which bind directly to collagen with collagen-specific glycoprotein Ia/IIa surface


I doubt that unerlying collagen is brought into contact with the blood by this teqhnique.

If a turniquet was an acceptable method it should be in the instructions.

A very good point, and as to why its not included I'll submit the following conjectures:
  1. Have you ever tried training the non technical? Its difficult and very very hard to get the point across. So training the trainers to train the people means you'll shoot for the easiest and simplest way to not get mixed and muddled messages across.
  2. There is a "standard view" which has apparently no supporting evidence that there will be an effect created by the torniquet. This is propagated in the medical industry and few question anything.

From: HNA04214 Coaguchek XS Manual :Layout 1 19/9/11 15:00
CoaguChek Meters
Training Guide

P33

Test limitations and known interferences:

The blood drop must be a minimum of 8uL in volume. Low sample
volume will cause an error message.
Testing performed with the above spiked in vitro samples or native blood
samples (triglycerides) indicated no significant effect on test results.

The known interferences did not mention massage, pressures or other capilary sample technique. I think therefore that its reasonable to assume that it doesn't make such a difference.

As it happens, I have friends who are pharmacologists, pharmicists and pathologists (not unusual for one who started his career as a biochemist). I have discussed this approach with all of them. The views are unanimous in "shouldn't cause a problem". One of them said the following:
"It's there for such a short time I think that if the extrinsic system started activating within 2 seconds of a tourniquet being applied, you need a lot more warfarin. In other words, I'd expect no interference."
and
"Concern about tourniquets is that they MAY cause the release of tissue factors, thus kicking off he coag cascade prior to blood sampling."

"It is the accepted wisdom, therefore tourniquet usage should be kept to a minimum. NB "kept to a minimum". That "undefined amount of time..." We were never pointed to actual studies, just told "this is the way things are"

He like me also believes that through open and considered discussion techniques are examined and advances made.

I know a little bit about medical device development. One test by one person at one time is not sufficient information for the FDA to allow the instructions for a medical device to be modified by the manufacturer. It takes a trial and comparison of results.

exactly, but you are assuming 2 things:
  1. that I would have only made one test.
  2. that the capillary sample technique is so tied down
I have already written here much earlier of me doing months of side by side testing before I cut across to self testing. I was dismayed at my initial attempts and then also concerned by the opinions of my professional friends on the accuracy of self testing. I actually have many samples of data where I honed my technique side by side with the lab.

FDA
http://www.accessdata.fda.gov/cdrh_docs/pdf7/K071041.pdf
http://www.fda.gov/downloads/AboutF...H/CDRHFOIAElectronicReadingRoom/UCM249934.pdf

In none of the FDA documents or the Roche Training or User manuals do they so much as discuss the technique in obtaining a capillary sample, yet there is mention as many as 8 times in training documents the importance of the 15 second rule. Further the device is now also recommended for use in evaluating blood from a VEIN sample ... if such minute variances in blood were a problem then its highly unlikely the device would be approved for both uses.

Lastly INR measurement is not an accurate science, it is inherently imprecise, only a guide. Even labs have significant variance in results on their reagent (consider if the tissue factor is sourced from human brain, human fetal materal, or rabbit). If there is a variance will it be significant to alter dose (the important issue). Good science is about replication of testing (administration and declarations by companies is a different thing), so if I get consistently good results then any decent curious person trained in science would want to see if they can replicate the experiment. The more who do and can the more likely it is that the theory can be accurately abstracted over many people.
 
Thanks for sharing Pellicle - good video. I just bought my Coaguchek XS this week. I wasted 2 strips because my blood drop was not big enough, so I turned up the lancet to 4.5 and got a much better drop of blood - all worked well on the 3rd try. I may try the elastic band as well. My first result was only 0.1 difference from the lab, which I had done about 12 hours later. You look much more coordinated than I do. I still fumble around a bit - I guess practice makes perfect!

T
 
Thanks for this all of you. I'm not anywhere near being allowed to home test yet, but appreciate the info and found a few things that might pertain to my situation. I've started another thread about problems with the machine not reading my INR anywhere near accurate at the AC clinic and the pharmacist thinking it's something in my skin that prevents accurate reading.
My question for here is about technique. I've noticed that in neither of the how to videos did you guys wipe your finger down with an alcohol wipe. Is that something just emphasized in the clinic environment? Would the alcohol wipe have any effect on testing results? (Although I will say, I've noticed at the clinic that they wipe off the initial drop and get the sample from second drop to form.)

Thanks again to all the old hats out there helping us newbies get comfortable with this whole thing!
Linda
 
Hi
My question for here is about technique. I've noticed that in neither of the how to videos did you guys wipe your finger down with an alcohol wipe. Is that something just emphasized in the clinic environment?

edit: I used to think this is a NONO ... but I just checked the latest manual and it says:
14414193802_5becb841b6_o.jpg


so it shouldn't make any difference. Personally I never bother with alco whipes (why create more garbage) and I also never use them in the gardening just before accidentally stabbing myself with a thorn either.

(Although I will say, I've noticed at the clinic that they wipe off the initial drop and get the sample from second drop to form.)

what machine are they using, there is an older machine with that as a procedure (INRatio I think??) but that is NOT the correct procedure for other machines. I'd say follow the manufacturers procedures ... mostly ;-)

My experience is that hospitals have often got someone who seems really competent but is really really doing it wrong. You'll find if you investigate cautiously (if you even can) that the person has been told time and time again that they're doing it wrong.

I had an INR taken at hospital one time when the nurse used a Coaguchek S (discontinued now) and broke all the basic rules of the manual. My INR came back 3.3 and they were doing to drop my dose. As I'd already been home testing I was confident she had done it wrong and as much as I hate vein draws I requested that be done before altering my dose. The vein draw came back 2.4 .... so just because its a Hospital does not make it infallible.

:)
 
Check your other thread. Hands are washed with warm water and the first drop is to used. You can also place your finger on the edge of the strip so your sample can be "sucked up".
 

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