T
Tom Kunich
Guest
"Suz" <[email protected]> wrote in message
news:[email protected]...
>
> "Tom Kunich" <[email protected]> wrote in message
> news:[email protected]...
>>
>>
>> Now add the way that the blood is drawn and from the location from which
>> it was drawn and it's easy to get a 10 point reading variation.
>
> No, it's not. 10 points is significant.
False readings in electronic platelet counters happens quite often for many
reasons. Some technician that is running the counter can make any number of
errors that would show up as ELEVATED HEMATICRIT. Likewise centrifuges read
a little high because they include the small amount of white cells and
leukocytes and hence many technicians 'correct' these readings downward.
Hematocrit measurements CAN be an exact science but it rarely is.
>> The only true test is a centrifuge.
>
> Wrong again.
Platelet readers are WAY more accurate than manual reading of cell counts.
However, as I said, there's any number of technical errors that can be made
which invalidate the readings of an automatic platelet counter. When you are
using a centrifuge you require a great deal more volume than you do with
platelet counters. This means that the errors in the 'fuge' counts tend to
be due to the corrections from leukocytes and white cells. Since these are,
generally speaking, predictable in normal healthy adults a centrifuge tends
to be a more accurate method of detecting hematocrit than an automatic
platelet counter.
Though I will say that the errors with either tend to be small. However, in
the case of someone claiming that their hct changed by 10 points in a week
you had better take that with a strong dose of salt. In all likelihood there
are some measurement errors and the patient was dehydrated on one occasion.
news:[email protected]...
>
> "Tom Kunich" <[email protected]> wrote in message
> news:[email protected]...
>>
>>
>> Now add the way that the blood is drawn and from the location from which
>> it was drawn and it's easy to get a 10 point reading variation.
>
> No, it's not. 10 points is significant.
False readings in electronic platelet counters happens quite often for many
reasons. Some technician that is running the counter can make any number of
errors that would show up as ELEVATED HEMATICRIT. Likewise centrifuges read
a little high because they include the small amount of white cells and
leukocytes and hence many technicians 'correct' these readings downward.
Hematocrit measurements CAN be an exact science but it rarely is.
>> The only true test is a centrifuge.
>
> Wrong again.
Platelet readers are WAY more accurate than manual reading of cell counts.
However, as I said, there's any number of technical errors that can be made
which invalidate the readings of an automatic platelet counter. When you are
using a centrifuge you require a great deal more volume than you do with
platelet counters. This means that the errors in the 'fuge' counts tend to
be due to the corrections from leukocytes and white cells. Since these are,
generally speaking, predictable in normal healthy adults a centrifuge tends
to be a more accurate method of detecting hematocrit than an automatic
platelet counter.
Though I will say that the errors with either tend to be small. However, in
the case of someone claiming that their hct changed by 10 points in a week
you had better take that with a strong dose of salt. In all likelihood there
are some measurement errors and the patient was dehydrated on one occasion.