Retaking blood test due to dehydration first time - anyone?

[ifonly4]

Has anyone had to retake a blood test due to lack of readings, thought to be due to dehydration? If so, did you think you were dehydrated? Did the second test throw anything up that wasn't expected.

This has happened to DH and they now want a urine sample as well, and I'm hoping there's nothing to worry about. He generally drinks one tea, one coffee, one very weak squash and about 2.5-3 pints walk a day, so I'd have thought that was enough.

What is the blood test for? The only issues I've had with not drinking enough water are simply not being able to get enough blood out.

He won’t have had all that at the time the sample was taken though. Many people ,who haven’t had anything (or much) to drink before a blood test, could be a bit dehydrated after a night in bed.
Lots of people have repeat blood tests that turn out ‘normal’ after the first test was out of range. Try not to worry, it sounds like they are being thorough.

This happened to my husband with early morning fasting blood tests , he used to go without drinking anything and it came back as a mild renal failure for a few years , we then realised what he had been doing , drank plenty before the tests and he was fine .

If it’s just that the sample didn’t provide any readings it probably means it clotted/haemolysed. It’s not usually anything to do with hydration but just that the sample took too long to take - just bad luck really. If the needle’s in a big enough vein blood will come out - dehydration doesn’t usually cause a problem (it may affect results like renal function, but it doesn’t often affect the quality of the sample). Better luck next time!

Thanks for your replies.

GP fairly sure he's got carpal tunnel syndrome and wrist supports helping, so looks like it's the right diagnosis. GP suggested blood test just to be sure nothing else was thrown up (DH hasn't been GP for a least ten years so not much history otherwise).

It wasn't a fasting blood test, taken at 4pm in afternoon (certainly shouldn't have been dehydrated as he's always got water on table even with a client). He's got an appointment for Monday at 12.30pm for another test.