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48 Hour Fasting Test.

Star*7

Member
Messages
8
Hi,

I was recently admitted to hospital for a 48hr fasting test due to low blood sugar episodes. (I'm not diagnosed with diabetes at all.) It was suppose to be a 72hr test but Dr said 48hr would be ok.

My finger prick blood glucose readings where:
1st day:
5.5 (2hrs after breakfast 1st reading)
5.3
Didn't get given next two readings.
Day 2:
3.7
3.3
3.5
3.1
Day 3 morning:
2.7
I didn't get told what the plasma blood glucose readings were but I know finger prick can give a different score than plasma blood glucose from what I have been told. Correct me if I'm wrong.
My ketones reading went from 0.2 and crept up over the 2 days but on day 2 it shot from 1.9 to 3.7 then to 3.9.

I felt absolutely awful especially on blood glucose 2.7, 3.1 & 3.3 readings. I just couldnt wake myself up and major palpitations, sweating etc. All the symptoms I get when I have these funny episodes.

At the end of the test they took a urine sample and blood for c-petide test and they forgot to transport this on ice to the lab so they rejected it. Trouble was I'd already started eating again so they couldn't redo the sample. Would this have messed the whole test up do you think?

I was so annoyed throughout the whole test and that just topped it off as no one had a clue what they were doing. (I was on a surgical ward) So so frustrating!!

The nurses didn't have a clue and I overheard them say 'oh just google it' which filled me with massive confidence.

Does anyone have any advice or insight into these readings or the test at all please?

I've had a look online and it says I should of received treatment if ketones are 3.9 as its dangerous. That worried me as they just sent me home.

Thanks
 
Well it looks like from those results you don't have diabetes so that's one positive.
Im no expert on low blood sugars (not many of us will be) so can't really comment on those.
As for ketones after a 2 day fast I'm not surprised they were well into nutritional ketosis but without high blood sugar then not problematic... so not a cause for concern... hence no treatment.
 
Sorry you have gone through this but as a retired nurse I must speak up for the nurses here. I don’t know why you ended up on a surgical ward rather than an Endo ward (winter bed pressures I’m guessing) but the nurses who were caring for you may well be very knowledgeable in their own field and the fact that they were Googling your issues was good in my opinion. It shows that they were concerned enough to learn about your problems. Anyway I really hope that you get some answers soon, do you have a follow up appt? Let us know how you get on.
 
Hi,

I was recently admitted to hospital for a 48hr fasting test due to low blood sugar episodes. (I'm not diagnosed with diabetes at all.) It was suppose to be a 72hr test but Dr said 48hr would be ok.

My finger prick blood glucose readings where:
1st day:
5.5 (2hrs after breakfast 1st reading)
5.3
Didn't get given next two readings.
Day 2:
3.7
3.3
3.5
3.1
Day 3 morning:
2.7
I didn't get told what the plasma blood glucose readings were but I know finger prick can give a different score than plasma blood glucose from what I have been told. Correct me if I'm wrong.
My ketones reading went from 0.2 and crept up over the 2 days but on day 2 it shot from 1.9 to 3.7 then to 3.9.

I felt absolutely awful especially on blood glucose 2.7, 3.1 & 3.3 readings. I just couldnt wake myself up and major palpitations, sweating etc. All the symptoms I get when I have these funny episodes.

At the end of the test they took a urine sample and blood for c-petide test and they forgot to transport this on ice to the lab so they rejected it. Trouble was I'd already started eating again so they couldn't redo the sample. Would this have messed the whole test up do you think?

I was so annoyed throughout the whole test and that just topped it off as no one had a clue what they were doing. (I was on a surgical ward) So so frustrating!!

The nurses didn't have a clue and I overheard them say 'oh just google it' which filled me with massive confidence.

Does anyone have any advice or insight into these readings or the test at all please?

I've had a look online and it says I should of received treatment if ketones are 3.9 as its dangerous. That worried me as they just sent me home.

Thanks

Hi, the fasting test is used for many reasons including Hypoglycaemia, which it does seem you have, but the reason why, I can't diagnose you, and the nurses couldn't either because until further tests are done, a true diagnosis will not be forthcoming.
I would hope to believe you have a follow-up referral from your medical team.
My type of hypoglycaemia was also diagnosed using this test, one of plenty!
However, I did not go hypo during the fasting test, and I lasted the full 4days plus.
So that would rule out reactive hypoglycaemia.
Let us know how you get on, keep on battling for more tests.

My hospital stay on a diabetic ward opened my eyes to how badly the NHS treat diabetes, but that was over five years ago.

My best wishes.
 
It appears you were being checked for insulinoma. Have they gotten back to you? You may have to redo the test.

It's unfortunate that they did not keep your sample on ice. You'd think they would know better, but people make mistakes sometimes.

https://www.healthline.com/health/insulinoma

Yes, it could be, but it could also be other forms of pancreatic conditions.
I agree, further tests are required.
 
Well it looks like from those results you don't have diabetes so that's one positive.
Im no expert on low blood sugars (not many of us will be) so can't really comment on those.
As for ketones after a 2 day fast I'm not surprised they were well into nutritional ketosis but without high blood sugar then not problematic... so not a cause for concern... hence no treatment.

Thank you thats reassuring. Not one person on the ward that I asked understood the ketones readings so it just worried me. One said if it goes over 2.0 it needs attention. You have reassured me.
 
Sorry you have gone through this but as a retired nurse I must speak up for the nurses here. I don’t know why you ended up on a surgical ward rather than an Endo ward (winter bed pressures I’m guessing) but the nurses who were caring for you may well be very knowledgeable in their own field and the fact that they were Googling your issues was good in my opinion. It shows that they were concerned enough to learn about your problems. Anyway I really hope that you get some answers soon, do you have a follow up appt? Let us know how you get on.

Thank you for your reply.

In no way am getting at the nurses I actually felt sorry for them over the 3 days, At one point it was 1 trained nurse to 17 patients she was nearly in tears.
My specialist arranged for this ward as it has more beds for the 48hr duration but they obviously don't get this regularly.

It really did not reassure me at all. Even after googling they were none the wiser. Really they should of rung endocrine and seeked advice. Not one nurse introduced themselves and they all honestly didnt know what to do. They argued amongst themselves at every handover on what they were suppose to be doing. There was a printed protocol for them to follow and it still all went wrong. Sadly the pressures of being on a surgical ward I guess.
I just hope it hasn't messed the results as I really wasn't a pleasant experience as it had a knock on effect on my other medical conditions.

I haven't got a follow up arranged yet but they said they will be in touch once they have the results so i'm hoping I receive a follow up appointment very soon. Thank you.
 
It appears you were being checked for insulinoma. Have they gotten back to you? You may have to redo the test.

It's unfortunate that they did not keep your sample on ice. You'd think they would know better, but people make mistakes sometimes.

Thank you. I really hope I do not have to redo the test as it made me feel so poorly. Thanks for the link.

They did have a protocol but it still went wrong. Hey ho!
 
Hi, the fasting test is used for many reasons including Hypoglycaemia, which it does seem you have, but the reason why, I can't diagnose you, and the nurses couldn't either because until further tests are done, a true diagnosis will not be forthcoming.
I would hope to believe you have a follow-up referral from your medical team.
My type of hypoglycaemia was also diagnosed using this test, one of plenty!
However, I did not go hypo during the fasting test, and I lasted the full 4days plus.
So that would rule out reactive hypoglycaemia.
Let us know how you get on, keep on battling for more tests.

My hospital stay on a diabetic ward opened my eyes to how badly the NHS treat diabetes, but that was over five years ago.

My best wishes.

Thank you for your reply. Yes I have had readings as low as 2.9 at home with my testing kit which led me to have this test.
I hope I can get to the bottom of it. Its not a nice feeling when I get lows.


I haven't been given a follow up at all yet but I asked when I left the hospital and she said they will be in touch once they have checked the results. I'll chase the sec in a week if I haven't heard anything.

What other tests did you have if you don't mind?

I will keep battling for sure as I can't carry on like this. Yes it is sad how little knowledge some have of the subject.

Thank you! :-)
 
Thank you for your reply.

Do you know what other tests they may do?

I believe, though mine were to get my diagnosis, that you will have had already full blood panel and other bloods taken to be tested for many conditions including insulinoma and other pancreatic conditions, probably a scan, perhaps as been suggested another extended OGTT.
I also believe that the doctors are awaiting those lab results, which will determine what tests are needed.

It's difficult to predict without more information.

Have you been advised what to do because of the hypos you are getting.

If not I would advise to have food every couple of hours to keep your blood glucose levels up above hypo levels.
 
HI @Star*7, As a diabetic, but not as professional advice or opinion, You really need the person who ordered the tests to discuss what those results mean. It is important that that be done soon. It would be absolutely ridiculous to say that you needed to have the urine and C-peptide test repeated before being seen.
I would honestly petition your GP to push for an appointment with the ordering specialist/team as soon as possible to help alleviate your worry and explain what the results mean and what the next step may be.
 
HI @Star*7, As a diabetic, but not as professional advice or opinion, You really need the person who ordered the tests to discuss what those results mean. It is important that that be done soon. It would be absolutely ridiculous to say that you needed to have the urine and C-peptide test repeated before being seen.
I would honestly petition your GP to push for an appointment with the ordering specialist/team as soon as possible to help alleviate your worry and explain what the results mean and what the next step may be.

Thank you for your reply.

Yes I'm going to ring his sec and chase it up if I will be getting an appointment to discuss the results.

The urine sample was for a Sulfonylurea test so is okay but i'm unsure what that test is for. The C-Peptide was suppose to go on ice so that test was rejected as they didnt follow the protocol. Unfortunatly they couldn't retest as I had started eating. I'm just worried it will spoil the test now not having that result. :( I don't even no what C-peptide is for either so if it will make a difference or not.
 
Thank you for your reply.

Yes I'm going to ring his sec and chase it up if I will be getting an appointment to discuss the results.

The urine sample was for a Sulfonylurea test so is okay but i'm unsure what that test is for. The C-Peptide was suppose to go on ice so that test was rejected as they didnt follow the protocol. Unfortunatly they couldn't retest as I had started eating. I'm just worried it will spoil the test now not having that result. :( I don't even no what C-peptide is for either so if it will make a difference or not.
A c-peptide test is used to find how much insulin is getting produced.
And to find out if you have insulin resistance.
 
Thank you! So basically it was an important test to hopefully give me some answers and they messed it up! Wonderful!! :bigtears:
Yes and no, the importance of you going hypo after two days means you don't have the type of condition that I have, reactive hypoglycaemia. This condition, I don't go hypo on a fasting test.
You did, which means that something else is happening, but that is why you need further tests.
The blood panel tests such as the c-peptide, is the part they screwed up.
So, they should repeat the blood panel tests and c-peptide as a matter of priority.
But do get on to them.

Best wishes
 
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