10 August 2011 (Wednesday) - Manual Clotting
Here's something interesting.....
A manual INR was performed yesterday - it was "slightly" prolonged at 14.0. Another colleague repeated the test and found it to be "slightly" less prolonged at 8.0. That's quite a difference.
It transpired that the first test had been performed in plastic tubes whereas the repeat had been performed using a reagent which had been warmed in a glass tube: the glass having caused activation of the reagent. Because manual clotting is in many ways a thing of the past, the nature of the tubes wasn't seen as being of any relevance to the younger staff.
Old 'uns like me remember these things.
With the advent of more and more automation, there are all sorts of little wrinkles like this that will recede into the annals of history. Unremembered until such time as they cause problems.