Hi
tom in MO;n882990 said:
So I'd like to test more often than once a month and do my own adjustments in the interim. In the past when an adjustment was needed, my personal guess for my new dose or adjustment was pretty much on target.
well actually that's probably pretty good anyway as you already have a lot of experience in this. To my observation most of the guidelines are centered around the idea of "starting" because once started warfarin dosage is totally guided by intention to keep within an INR range, thus the dosage is simple.
When I call it in, the nurse takes a few hours to respond when you are out of range. I assume (maybe incorrectly) that he/she goes to some computer program or set of decision rules which tells them what the adjustment should be. This is then "approved" by the doctor and that's the charge I see.
You are correct that there will be software, indeed a google search shows many options on the market (I could paste in a few that I've found however they're clearly aimed at clinics. Back when I was researching things more actively (2012 ~2014) I found a number of good papers which formed the basis for my approach. One was a 2009 paper (submitted as thesis research for a PhD) which undertook an analysis of 2 such softwares, She compared ICAD and TRODIS which was ultimately passed by an experienced clinician to make the final determination (probably because its easier to hold a person responsible than a machine). I expect that AI systems may indeed emerge soon (perhaps).
I can send you that paper if you want, but my take on it was that (and it did such analysis) without properly taking into account the VKORC1 and CYP2C9 genetic types (requires a blood test and genetic typing) that the results of algorithms were less than perfect.
This site still seems to work:
www.globalrph.com/warfarin_calc.htm
however if you read it you'll see that its really mainly oriented for starting patients. Us long termers need to have gathered our own data.
If you need any help on this please feel free to email me and I can share a spreadsheet (google sheet) which I can talk your through and which will make things easier (assuming you don't already have something like that now).
Best Wishes