Ask The Expert
Monitoring

Naturally I am very concerned because the situation you described is serious and one that needs immediate attention so that you can prevent future occurrences. I can't tell from your message if this was a recent occurrence or not, and you did not describe your insulin regimen. While I have already responded to you individually urging you to contact your doctor immediately, I wanted to post this message for the benefit of others in your situation.

Level of Glucose to Cause Loss of Consciousness:

• Although I have extensive references on hypoglycemia, it is very difficult to find a definite answer to your question for a variety of reasons:
• Until only recently, many glucose meters did not read below 40 mg/dl, and even if they did, their accuracy was not as reliable at low levels.
• When you are in severe hypoglycemia, your body attempts to correct/reverse the problem by releasing counter-regulatory hormones that stimulate the liver to release glucose. Thus, sometimes the glucose is already rising at the time the blood glucose is tested by the paramedics.
• Most references explain that you begin to develop impaired thinking when the glucose gets below 50, but it depends somewhat on how rapid your glucose falls, as well as whether you have hypoglycemia unawareness. In the link I provide to the right on hypoglycemia unawareness, I explain the role of the hormones that attempt to protect you.
• A JDRF (Juvenile Diabetes Research Foundation) Countdown article (no date available) provided these approximate numbers: Coma can occur at glucose levels around 30, convulsions at 20, and permanent brain damage at 10. However it is very important to note that these numbers are simply not true or exact for everyone. Research has shown that you can develop memory loss and other impairments from repeated low blood glucose, even if it doesn’t get all the way down to 10.
• It is important to note that other factors can interfere with your ability to recover from hypoglycemia—most importantly: how much insulin is in your system, recent alcohol ingestion (which prevents the liver from being able to release glucose and can cause low glucose up to 12 hours later), how much food is in your system, and how long since you exercised, among other factors. For example, exercise can affect your blood glucose from 12-72 hours later, causing a delayed hypoglycemia

Hypoglycemia Unawareness:

Another concern is whether or not you have hypoglycemia unawareness, a condition in which you have lost your ability to recognize symptoms of low glucose. This is obviously a serious problem, but interestingly, sometimes it is reversible with careful management of your diabetes.

Driving Dangers:

Studies have shown that many people with diabetes cannot accurately judge their blood glucose or their ability to safely drive when their glucose is low. Even if they perceived they were low, they often thought they could drive safely. Yet, while a study showed that driving was impaired at blood glucose levels below 70 mg/dL, the subjects didn’t treat their hypoglycemia until they were below 50 mg/dL.

What might have been occurring in your situation is that you could have had several severe lows, but not low enough to require medical attention. These repeated lows could contribute to your developing hypoglycemia unawareness. In addition, if you were stopped by the highway patrol or treated by the paramedics but were not taken to the hospital, it is possible that no one notified your doctor. State laws vary, but in some states, if you are treated at a healthcare facility for being unconscious, the doctor is required to notify the DMV, and sometimes you may temporarily lose your driving privileges.

Contact Your Doctor Immediately:

Regardless, what concerns me most is that it seems that you might not be communicating this situation to your doctor.

Please note that in almost all cases, the situation you described should be preventable with proper education as well as using the appropriate insulin regimen, and testing frequently. For people with severe extremes in blood glucose, generally the best options are either a multiple shot regimen using a rapid-acting insulin with each meal, and a long-acting at bed, or an insulin pump.

So as I have repeatedly said in this message, it is very important that you get help as soon as possible for this situation, and take action to prevent having any further lows.