If my sugar gets down to a level anywhere near 27 I should be pretty concerned but may not have the mental capacity in that state to realise I should be A.) testing my sugar B.) be doing something to raise my sugar. I would imagine if I was at 27 I would be going to the hospital.
If I ever had a vacant look or catatonic look I would want my friends so just ask me if I have checked my sugar. Maybe suggest that I have some juice or pop. NEVER inject my insulin for me. EVER. Now, I wouldn't appreciate my friends always asking me this sort of thing, only if I appeared abnormal. Diabetics tend to feel judged when it comes to their numbers because society is told Type 1 Diabetes is "manageable" which it is, it is just extremely challenging and the body doesn't always co-operate.
I use Humalog for my meal time insulin and it starts working about 15 minutes after I take it. It continues working for approx 3-4 hours depending on certain factors. Now sometimes diabetics accidentally "insulin stack", that means take their insulin with a meal, get hungry an hour later and have a snack and take more insulin, at this point there is more "insulin on board" than normal. This is not a good thing. This may also be causing the diabetic to start to already go low and then they have another snack and more insulin because they are in a confused state. This sort of thing is easy to let happen. I have also had one severe low where I took my breakfast insulin and forgot to eat. These sorts of things just happen sometimes. Also, in the summer, if it is hotter, insulin can work quicker. Even the weather affects insulin! I know that my insulin requirements go down about 25% in the summer because of the heat. This can vary day by day. That is just one example of how sensitive and erratic my body is to insulin.
I know that people without Type 1 Diabetes don't understand that when someone is low they are not themselves. Please remember that when dealing with your friend if he gets very angry, sad, volatile, not himself, etc that could be a sign his blood sugar is low or high. My emotions go crazy when I am low. If I freak out it is a guaranteed cue for my wife to ask me to go test my sugar, 99 times out of 100 I am low. The other 1 I am being an idiot/jerk.
As far as my thought process and cognitive ability go when I am low; if my sugar is around 70 I feel like I have had a few drinks, if it is around 40 I would feel like I have had a case of beer and a few shots for added measure. I probably would not remember that low the next day. That is really the only thing I can compare it to that most people would understand. For me sometimes with my hypoglycemic episodes (lows) my vision actually looks like a drugged persons vision on some thriller TV show. You know the shaky camera work, the breathing, the confusion. It can be scary.
To be clear, these sorts of lows are really rare for me. I am lucky, I usually catch them around 70 and have a small can of Coke and I am good. Other people have more trouble recognizing their lows, this is called hypoglycemic unawareness and this is more common in people who have had T1D for years. As the body has more lows it can get more insensitive to them and they are hard to recognize. You may want to look this up, I am sure you would learn lots and it would be very helpful to you in possibly understanding your friends situation.
Having Type 1 Diabetes is a very mentally demanding. The sad fact is that my life depends on me doing numerous mathematical equations everyday and sometimes doing them while not all there mentally. This is no different than anyone else with T1D. With the exception of children whose parents have to make those calculations and I am sure that takes the pressure to a whole new level!
All of this said if you are that concerned about your friend (which you probably should be seeing as he is requiring that much emergency medical attention) you should maybe try to have a chat with him. See if he is ok with you asking him what his sugars are if he is appearing erratic. Ask him where he keeps his sugar in his home. Where does he keep it when he is on the go? In his pocket? Bag? Does he have liquid glucose available? If so where does he keep it? What other emergency measures does he have? Does he have a medic alert bracelet, chain, watch, tattoo, etc. for when friends are not around? Ultimately it is up to him with how comfortable he is sharing his health situation. Everyone is different and everyone should make their own choices based on their comfort level but having your friends know where you keep your emergency sugar is a must.
Don't be offended with his response but please tread lightly. PWD (people with diabetes) tend to be pretty defensive when it comes to this sort of stuff (by this sort of stuff I mean anything diabetes related) but it is only because we often feel judged for our condition. I often hear people say that someone "wasn't taking care of themselves and their diabetes" and X happened to them, as if that person wasn't even trying or they got exhausted from trying (Diabetes Burnout, another good thing to perhaps look up). I am certainly not saying this is you. At all. You are obviously a concerned friend but PWD hear those sorts of comments all day from strangers, acquaintances, TV shows, etc. So, when someone they actually care about brings up any aspect of their diabetes they can feel even more judged. "Great, society thinks I am not taking care of myself and now my friends do to."