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much water before ultrasound test?
marthapsj posted:
My elderly mom is trying to understand instructions before her first ultrasound test of her kidneys. Someone, speaking super-fast, called to set up her test appointment the other day. Part of the instructions that whizzed past seemed to involve the requirement to drink at least 24 ounces of water before the test. Since she typically drinks a few sips of water at the most and frequently sprints to the restroom at the best of times, she is alarmed at the idea she might actually have to drink all that water and then hold it in(??). Naturally, we'll try to get some clarification from the doctor if we can, but can anyone explain what's behind this? Is 24 ounces a "magic" number or just a general guideline? How much can this intake be spread out (many hours before the test or just the last hour or so)? What if she can't hold it till she gets to the doctor's office? How critical is it? Thanks for any explanations or insights.
John-SKPT responded:
If it is an ultrasound of the kidneys and not of the bladder or ureters, then the large volume of fluid is just to insure that she is not dehydrated, that the bloodstream has plenty of volume to expand the veins and arteries to their normal limits so that they get better images. She shouldn't need to try and 'hold' any urine back, it's just to be sure that the system is not dehydrated. You really should check again with the doctor's office just to be certain, but if what I assume is correct, then that it the reason. But you should never assume things with medical tests. There are other tests, for example radionuclide tests, and the water consumed must be taken in at a very specific time frame for the test to be accurate. So do phone the office again and ask for clarification of the instructions.
marthapsj responded:
Thanks, John. That helps give us some perspective!
Wingsy80 responded:
I was told 16 ounces before my last kidney ultrasound, but they were also checking my bladder as well. I had to have a full bladder for about 2 minutes, then they let me go to the bathroom before they finished checking my kidney.

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