By Aaron Dixon, MBA, NRP
To understand diabetes, you must first understand hormones. Hormones are responsible for all basic bodily functions; they are not just the stuff coursing through your teenage children’s bodies, making them impossible creatures to deal with.
Think of a hormone as a key that fits the lock on a particular type of cell. For each hormone (key), there is a matching receptor (lock) on the cell membrane of certain cells. Each cell has several hormone receptors that perform a specific function when activated.
The same receptors can be found on multiple types of cells and cause different reactions. The function of a hormone is largely determined by the location and type of the cell that it interacts with. For instance, epinephrine, a very potent hormone, causes vasoconstriction of the blood vessels. Like the opening and closing of a nozzle on a hose, the smaller the opening in a blood vessel, the higher the pressure of the blood moving through it. When epinephrine is released, it binds to the cells on the blood vessels and the blood vessels constrict. Receptors for Epinephrine are also found in the lungs. When epinephrine binds to the receptors on cells in the lungs, bronchodilation occurs. Both mechanisms are the reason why epinephrine is given to treat anaphylaxis.
Insulin is the primary hormone involved in diabetes. When blood glucose levels rise, the body secretes insulin. Insulin (the key) then binds with the correct receptors (the lock) allowing glucose into the cell. In Type I diabetes, the body does not produce insulin. As discussed in the last issue, the resulting disease processes cause Diabetic Ketoacidosis and death, unless treated with daily injections of insulin. In Type II diabetes, the problem is not with the production of the hormone, insulin, but with the receptors on the cells.
While Type I diabetes is one of the oldest recorded diseases in history, Type II wasn’t really recognized until 1936 when a British physician named Sir Harold Himsworth, recognized a condition of insulin resistance. The body produced insulin, but it could not utilize the insulin correctly. While Type II has been identified for 85 years, there has been a sharp increase in cases over the past 20 years – mostly attributed to the rise in obesity. Type II diabetes is now one of the most common chronic medical conditions found in the United States.
Patients who have Type II diabetes produce insulin, but the appropriate receptors in their bodies are damaged. While Type I diabetics will die from Diabetic Ketoacidosis (DKA) without medical intervention, Type II diabetics will not. Because insulin is present in the body, fats are not broken down and ketones are not produced. With insulin being produced but unable to bind correctly to its receptors, blood glucose levels rise. Type II diabetics can run chronically high blood glucose levels resulting in a profound increase of risk for heart diseases, stroke, blindness, renal failure, and a myriad of other problems such as impaired wound healing.
Glucose is abrasive and destroys the inner lining of the blood vessels. As the blood vessels get damaged, fat can deposit within the arterial walls and scar tissue can form. Both issues increase pressure within the organs increasing their risk for failure. Scar tissue in the vasculature prevents the movement of white blood cells from the blood to infected and injured areas reducing healing and clotting.
A rare but fatal condition, Hyperosmolar Hyperglycemic Syndrome (HHS), can occur when prolonged extremely high glucose levels lead to profound dehydration. These patients can have glucose levels in excess of 1000 mg/dl. These patients will present typically as unresponsive, tachycardic, and hypotensive. Most prehospital glucometers will only read to 500 mg/dl. These patients will return a reading of “Hi”. The prehospital treatment is ensuring a patient airway, oxygenation, and fluids to correct volume depletion. While HHS will cause an increase in respiratory rate, it is not as deep and rapid when compared to Kussmaul respirations seen with DKA since there is no acidosis.
Unlike Type I diabetes which is treatable but not curable, patients with Type II can be completely cured of the disease. The treatment of Type II diabetes combines a mixture of behavioral changes including diet and exercise, and typically an oral diabetes medication, such as Metformin. Most Type II diabetes medications work on improving glucose metabolism and slowing the conversion of carbohydrates to glucose. One class of medication, Sulfonylureas (Glipizide, Glimepiride, and Glyburide), increases insulin levels. These medications can cause hypoglycemia. Eventually, a Type II diabetic will be prescribed insulin if diet, exercise, and oral medication do not sufficiently reduce glucose levels. Some of you may be thinking, what is the purpose of more insulin if the receptors are damaged? The answer is no, different than why we titrate any medication. Adding more hormone or medication increases the number of receptors stimulated, and for longer periods of time, thus increasing the effect.
So how does this translate to your job in fire or EMS? First and foremost, Type II diabetes is preventable and curable, so take care of yourself. Actively manage your health, exercise, and eat correctly. Say no to those roller dogs at the 24/7 gas station–choose a bag of nuts instead. When a primary reason for line-of-duty deaths is attributed to heart disease, fix one of the main risk factors. Second, regarding your patients, even though hypoglycemia is not common in Type II diabetes, you must check your patient’s blood glucose. Make sure you compare your result to their historical average. Most diabetics will know what their blood sugar typically runs. If your patient has a normal average of 300mg/dl and it is currently 90 mg/dl, they will appear hypoglycemic. If and how you would treat these patients should be dictated by your local clinical operating guidelines. However, if you have what appears to be a stroke patient with a low glucose per their norm, I suggest correcting it before calling a stroke alert. Third, remember that Type II diabetics can run abnormally high glucose levels and present as normal. This is in stark contrast to a Type I who can be in DKA with a BGL of 275 mg/dl. Treat based upon the symptoms, vital signs, and patient presentation, not just the glucometer reading. You know the old saying, “treat the patient, not the monitor.”
Diabetes is a very common disease and accounts for a high number of EMS responses. Hopefully, the last two articles provided a decent overview of diabetes and will help improve your patient assessment and development of differential diagnosis. Be safe out there.
Aaron Dixon, MBA, NRP, is the Executive Director of EMS for Prisma Health, Commissioner for Clear Spring Fire Rescue, and an Executive Board Member of the SC EMS Association. Prisma Health operates a large EMS department providing 911, ALS, Mobile Integrated Health, Emergency Medical Dispatch, and Critical Care services throughout the Upstate and Midlands of South Carolina. Dixon is a national speaker and has authored multiple articles. He can be reached at firstname.lastname@example.org.