Best time to test blood glucose

[Mel and Oreo]

Hi,
Our vet has instructed us to test after our cat Oreo eats then give insulin based on that value. We have been testing before he eats. Before eating he runs at 20 to 24 Metric. So we gradually increased his caninsulin from .5 units twice daily to 2 units twice daily now.
I did a blood glucose curve and he had his nadir at 4 hours after his dose and hit 6.6. The next morning I tested before food and he was 12.4. Vet said that we should feed then test and base insulin on that number. She said if it is 20 or above give 2 units, approx 16 give 1.5 units and greater than or equal to 14 then give no insulin. I waited 20 minutes tonight after food and he was 20.4 so I gave 2 units and will retest in 4 to 6 hours.

Thanks,
Mel and Oreo

 

[Deb & Wink]

Test before food.

With any insulin, you ideally want a non-food influenced pre-shot number before you give each shot. We suggest not feeding for 2 hours before the pre-shot test, to get a true reflection of the BG number.

With Caninsulin, you do want to feed your cat first before you give the shot. This is because Caninsulin has a faster onset, steeper, quicker drop than the depot insulins and you want some food on board first to help level things out with the BG's.

 

[Mel and Oreo]

If you want a test before food what does that test number tell you and what do you do with his insulin dose based on that number?
My Oreo was at 119 +4 yesterday. Then when I tested him before his food this morning he was 223. 25 minutes after I fed him he was 372. What do you do if the test before food is in a certain range? When should I not give insulin? My vet said to test him after food and if it is more than 360 give him 2 units and if around 288 give 1.5 units. She said if 252 or less to not give insulin.
We thought she meant before food and because it was 223 ( less than 252) we skipped his insulin this morning. My husband retested in the afternoon and he was in the 372 range so he stayed high all day. This indicates to me that I should test after food and that the pre food test just tells me that the previous insulin dose kept him within a certain range.
I need help!

 

[BJM]

Pet-specific vs human glucometers is like reading temperature in Fahrenheit vs Celsius.
Both are correct. As long as you have the reference numbers for the one you are using, you know how to interpret the tests you get.

[Glucose reference ranges are unsubstantiated and have been removed by Moderator]

* * * * * * * * * * * * * * *​

How to use the glucose reference values chart:

When you get a test, look for the number on the chart that either equals, or contains, the test value you have. Read the information. As needed, make a decision and act.

Ex. You are a new insulin user and you test your cat before giving insulin. The test is 300. It probably is safe to give insulin.

Ex. You are an established user of Lantus, following the Tight Regulation protocol. You've tested around +5 to +7 to spot the nadir. It is 200 mg/dL. You probably need to increase the dose, following the instructions for the protocol.

Ex. Your cat is acting funny. The eyes are a bit dilated. You are concerned and test the glucose. The number is 35 mg/dL. ACK! The cat may be in a hypoglycemic state. You quickly follow the HYPO protocol linked in the glucose reference values chart. (which we really, really, suggest you print out and post on your refrigerator.)

 

[Mel and Oreo]

Thank you BJM,
I understand, but what I don't understand is if the before food blood glucose test is in normal range does it just mean that the insulin has kept its long term effectiveness and then when I test after food and Oreo is in the 300 range it means that I give him his usual dose or if that test is still in the normal range then I should not give the insulin.
In a human diabetic they test before to see if in normal range and then test two hours after the first bite of the meal and this must be back in normal range or they need an increase in insulin or decrease/ change of diet. It is a balance between the pre food reading and how much food and what type of food they eat.
If I keep Oreo's food as consistent as possible I should watch the before food test for insulin effectiveness, after food to see how high he reaches, the nadir to watch his low and the mid point between nadir and pre food test to see if insulin has longevity.
If you test before food and very low, but then 300 after food wouldn't you just give him his insulin dose as usual, but then give him a snack possibly 2 hours before the pre food test to keep him in a more normal range during that time?
How do you tell if your cat is in remission? If the before food test is normal then doesn't that just tell you the insulin had been effective for the whole 12 hours. If that before food test is extremely low (how low?) does that tell you that the cells are producing insulin and producing hypoglycaemia when combined with your insulin dosing.
Help

 

[Mel and Oreo]

I need to know if the no shot limit of 8.3 is for a test done pre food or after food. If that value was taken before food wouldn't it just mean the insulin has been effective keeping Oreo in range? If I took this reading after food I would think he would not need his insulin. Is this correct?

 

[Wendy&Neko]

Melanie, there is a Caninsulin User Guide over on the Vetsulin/Caninsulin/Humulin Forum. You might want to take a look at what it suggests.

BTW, the majority of people here are in the US, so we report our numbers in mg/dl, even though in Canada we use mmol/L. Just multiply the number on your glucometer by 18 and you'll get the mg/dl number. Alternatively, you could set up a spreadsheet to record Oreo's blood glucose numbers. The directions are here. It has tabs for both formats so you can enter data in mmol/L and it will convert. The people here who give suggestions on dosing are used to doing so by looking at the spreadsheets. You'll see most of us have a link to one (or more) in our signatures.

And congrats on getting that first curve done! The first one is the hardest and it will get easier for both of you.

 

[BJM]

I need to know if the no shot limit of 8.3 is for a test done pre food or after food. If that value was taken before food wouldn't it just mean the insulin has been effective keeping Oreo in range? If I took this reading after food I would think he would not need his insulin. Is this correct?

The pre-food test is evaluated for safety of shot. Until you have a fair amount of data, you do not know how low the dose will drop your cat. Once you have an idea about that, you may gradually shoot lower.

When it is lower than your limit, without feeding, wait 30 min and re-test. If rising, or above the limit (initially 200, then gradually reduce to 150), it may be safe to shoot. The first time or two you do this, you should be home to monitor during the cycle and also have extra strips, Karo, and high carb gravied food at hand just in case the cat goes low enough there is a concern for hypo (50 mg/dL on a human glucometer, especially any time before nadir)

 

[Deb & Wink]

I need to know if the no shot limit of 8.3 is for a test done pre food or after food.

The 8.3 mmol/L (150 mg/L) limit is pre-food, pre-shot.

In a human diabetic they test before to see if in normal range and then test two hours after the first bite of the meal and this must be back in normal range or they need an increase in insulin or decrease/ change of diet. It is a balance between the pre food reading and how much food and what type of food they ea.t

Humans may test +2 hours after the shot and base dosage adjustments on that number, but cats process insulin a bit differently and each cat reacts differently to the various insulins. You want to test somewhere in the middle of the insulin cycle, which with Caninsulin may only be 8-10 hours long. That would mean testing somewhere between +3 to +5 to find when you cat Oreo gets his lowest reading. You may need to test different times on different days to find the normal nadir for Oreo. That nadir can also vary a bit from day to day.

what I don't understand is if the before food blood glucose test is in normal range does it just mean that the insulin has kept its long term effectiveness

Not necessarily, it may mean that the dose is too high. It may mean your cat no longer needs insulin. If the pre-shot pre-food test is in the normal range, you do not want to give any insulin that cycle.

then when I test after food and Oreo is in the 300 range it means that I give him his usual dose or if that test is still in the normal range then I should not give the insulin.

How soon after you have fed are you testing again? 20-30 minutes? 2 hours? 3-4 hours? If Oreo is in the normal range at pre-shot test, do not feed, wait 20-30 minutes and test again. We want to see if the BG levels are rising or falling, still without any food influence. Food is going to make the BG's go up so you hold the food for a bit if the numbers are in a normal range and then retest to make sure it's a rising or steady number before you shoot. This is what we call "stalling".

You really need to have more data before you shoot any insulin at these low or normal numbers.

This is where having that spreadsheet setup would really help us to help you better.