Scary 4am Low: A Cautionary Tale

I’m a little rattled this morning by the events that played out last night when I should have been sleeping peacefully.  I’ll do my best to convey them here now:

I went to a holiday party last night and both drank and a ate a bit closer to bed time than I like to; it seems the food in my stomach when I’m sleeping digests a bit quicker and I tend to spike a bit higher than I might if I didn’t go to sleep so soon after eating.  I also walked home from the party and was seeing double down arrows on Dex and a BG of 175 which from experience I knew would either level off at 175 once I stopped walking/went to bed, or would continue to raise one I went to bed and super-digestion commenced.

So, I went to bed last night expecting a bit of a BG-coaster but after a comedy of errors, what I got was so much worse.

Here’s what I remember:

Around 4am, I hear M asking me if he should get me some orange juice. I must have been feeling the low at that point because M usually responds only to my squirming and not to the sound of Dex. I also must have been pretty low because when he asked, rather than saying “no” like I normally would do and getting the juice myself, I said “please” and I put my head on the pillow and let the cold sweat drip over my skin.

He brought back a full, tall glass of orange juice (at lease 4x what I would normally use to treat a low) which I drank in two gulps.  He got a second glass that went down just as easily.  I lay there for a couple minutes to try and let the juice absorb when I decided to actually look at Dex.  58 mg/dL.  Not too bad. But 58 wasn’t really a good description of how I felt. I felt sub-zero. So I grabbed my meter and checked.  32.  That’s more like it.

I went into the kitchen and ate a few spoonfuls of pistachio Haagen-Dazs and Nutella.  M came to check that I was ok and laugh and my standing in front of the open freezer with a carton of ice cream and a spoonful of chocolate.  I went back to bed and back to sleep.

In the morning, I assumed I would be sky high but Dex was only reading in the 120′s.  A check with my meter confirmed it.

7 am BG after overnight low.

7 am BG after overnight low.

WTF? Where’s my sky high BG that should have followed my massive 4am consumption?  Looking at Dex confused me even more – this low occurred after a rapid drop in BG at 2am.  I must have awaken to the sound of Dex alerting me to a high and I must have groggily corrected my BG of 185 (as determined by Dex) and corrected with a bolus from my shiny new t:slim pump.  (Now, I know I shouldn’t be correcting from my Dexcom, but I do. And I’ve found it to be reliable enough and even when it’s not the outcome is generally not so far off to be a problem. Generally.) This is the sort of overnight correction I am in the habit of doing, and doing it is barely a blip on my radar and happens mostly on autopilot.  So, I decided to check my pump history to see if this was the case.

t:slim history screen showing a surprise.

t:slim history screen showing a surprise.

Looking at the above image, I was shocked.  I initiated a 15 u bolus at 2:24 in the morning.  Why?  Purely by accident apparently.  The t:slim displays 3 things for every bolus: the time at which it was completed (boluses can be a bit slow, in this case at 2:48 am), the time it began (2:42 am) and what was entered to initiate the bolus.  See in the picture it says “B: Food/BG” then “183 g/NA”?  This means I bolused at 2:42 am for 183 g of carbs rather than a BG of 183 mg/dL!  What should have been 2 u was 15 (max bolus allowed by my pump settings).

How can I make such a stupid mistake? I’ve only been using the t:slim for about a week and I love so many things about it, including that I no longer have to dial in  the units for a bolus.  However, dialing in that number has always provided me with a check that I couldn’t ignore before delivering a dose of insulin. The t:slim asks me 3 times before delivering a dose; it does a good job of shoving information in my face.  What it doesn’t to is engage my brain enough during autopilot to help me see the error of my ways.

This is what you see when you initiate a bolus with the t:slim

This is what you see when you initiate a bolus with the t:slim

The bolus screen clearly indicates where to enter a BG and where to enter carbs.  However, once you click, the next screen is nearly identical for each:

BG or carb keypad

BG in carb windowBG in BG window Keypad; BG in carb window; BG in BG window

Once the numbers are entered, it displays a calculated dose then you hit “next”, confirm twice, and done.  The bolus initiates and the pump vibrates quickly upon completion.   With auto-pilot initiated, I entered and confirmed and was asleep long before the vibration.  End of story.

So.  What have I learned?

  1. The obnoxious dial-a-bolus method used in all other pumps may have irked me most day,s but it did provide me with a mental check that probably would have prevented this from happening.
  2. Actually using my meter to confirm my Dex BG would probably have taken my brain far enough out of autopilot to notice my mistake and prevent this from happening.
  3. For some reason, my first instinct when I go to calculate a bolus is to click on the left most box first, and when my brain is in BG mode instead of carb mode, there is potentially a problem.

I started with the t:slim about a week ago.  While I am still smitten by it, I’m realizing I need to approach this change with a bit more caution that I have been.  I’ve had Animas’ pumps for about 12 years and I can use one with my eyes closed.  I’m going to have to spend some time focusing more on D and destroy my old auto pilot (or at least reprogram it).

About these ads

One thought on “Scary 4am Low: A Cautionary Tale

All comments are welcome!

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s