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July 24, 2003


Today has been a day full of contrasts, but mostly positives. The night was difficult, mostly due to mundane things like indigestion and gas pains. I had a mild fever with mild chills but that wasn't too bad. My nurse made me eat a snack at about 4am so I could take a MONSTROUS Potassium pill without stomach upset. My snack consisted of diabetic strawberry jello and 4 saltine crackers. I don't recommend the diabetic jello and the crackers were stale. That brought to mind an old navy shipboard practice of deep fat frying stale saltine crackers and serving them anyway. Back to my current life, my rashes are all healing. My lab results are encouraging. My platelet levels are in the normal range, my hemoglobin is sinking very slowly compared to previous days. While the WBC is still low, the doctor feels my lack of fevers other than those induced by drugs indicate that I have WBC combatting pyrolytic elements in my body. They are still playing with my Coumadin and Heparin to try and get them under control. My kidney functions appear to have taken a turn for the better with a substantial reduction in my Creatinine levels. In addition to Creatinine I am continuing to lose a lot of the fluid weight that I picked up when my kidneys failed. There is a rumor flying about that I might have a bone marrow biopsy next week to see if I am in remission. If so, my treatment will settle into a long process called continuation chemotherapy. I will know more about that when I get to it.

On the sad note, the rest of my family left today to go back to their daily lives. While I wasn't much fun to be with while they were here, their visit was nevertheless very much appreciated.

On the medical front, for all you techno geeks, here is the authoritative definition of INR. The answer you've all been waiting for. For the rest of you, you have permission to skip to the Lab results! :) Of course, if you read all the way through this, you know you are a true medical techno geek!

What is INR?

International normalized ratio (INR). The INR value depends on the sensitivity ratio of the thromboplastin reagent used in the laboratory relative to the International Reference Preparation (IRP), a sensitive thromboplastin prepared from human brain.

This standardization system was introduced by the World Health Organization (WHO) in 1983 to provide a common basis for the interpretation of the PT results independent of the sensivity of the laboratory thromboplastin reagent which tends to vary from one manufacturer to another. The INR is derived from calibrations of commercial thromboplastin reagents against the International Reference Preparation (IRP). The calibration yields a value called the International Sensitivity Index or ISI. The manufacturer provides the ISI value for each lot of thromboplastin reagent. The lower the ISI value the more sensitive is the thromboplastin preparation. For the three commercial rabbit brain thromboplastins currently used in the US and Canada, the ISI ranges from 1.3 to 2.8.

The INR is calculated as the observed PT ratio raised to ISIth power as shown in this equation: INR = (observed PT ratio)ISI

The "observed PT ratio" is the ratio of the patient's PT divided by "the control PT". The control PT is often a constant value for each laboratory and it is referred to as the lab's average normal PT. Here are some examples: p>






19 12 1.3 1.82
20 12 1.8 2.51
15 12 2.8 1.87
23 12 2.4 4.77

For most indications, the recommended INR is 2 to 3. For prosthetic heart valves the INR should be maintained between 2.5 and 3.5

Lab Results

Blood Cell Type

Normal Low




WBC 4.5 .2 .2 .3
RBC 4.30 2.69 2.69 2.63
HGB 13.9 8.4 8.2 8.1
PLT 130 87 197 233

Have a great day.


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