Introduction
For prehospital providers, there are several causes for the patient with altered mental status or being unconscious to include the mnemonic AEIOU TIPS for Alcohol and acidosis, Endocrine, Epilepsy, Electrolytes, Encephalopathy, Infection, Opiates, Overdose, Uremia, Underdose, Trauma (head injury and blood loss), Insulin, Poisoning, Psychosis, Stroke, Seizure, and Syncope. Hypoglycemia, or low blood glucose level, is one of the most common causes of altered mental status for patients with and without diabetes. Estimates are that 1 to 2 percent of prehospital encounters and 7% of refusals are for hypoglycemia.[1][2]
Diabetes mellitus often referred to as "diabetes" or "sugar" by laypeople is the most common endocrine disorder where the body does not either produce enough insulin or has a resistance to the circulating insulin, and is characterized by high blood sugar levels over prolonged periods. The three main types of diabetes are type I (previously referred to as insulin-dependent diabetes mellitus (IDDM) or juvenile-onset), type II (formerly referred to as non-insulin-dependent diabetes mellitus (NIDDM) or adult-onset) and gestational.[3] Insulin is an anabolic hormone produced in the beta cells of the pancreatic islets. The primary function of insulin is to regulate the metabolism of carbohydrates, protein, and fat through the absorption of glucose sugar from the blood into the liver, fat, and skeletal muscle cells. These small glucose molecules are then converted into larger molecules and stored for later usage.
Type 1 Diabetes Mellitus (T1DM) [4]
This condition is commonly referred to as insulin-dependent diabetes or previously as childhood/adolescent-onset diabetes. It accounts for approximately 5% to 10% of all cases of diabetes. It can be related to the autoimmune destruction of insulin-producing beta cells in the islets of the pancreas from different causes, including genetic susceptivity, viral illness, toxins or alcohol-induced pancreatitis, or some dietary factors. The age group affected is usually children and adolescents, but adults can develop T1DM. As the name "insulin-dependent" implies, it requires the administration of subcutaneous insulin via intermittent injections or pump infusion.
Type 2 Diabetes Mellitus (T2DM) [4][5]
This variant is commonly referred to as non-insulin diabetes or previously as adult-onset diabetes. It accounts for approximately 90% of all cases of diabetes. It is related to the desensitization of insulin/insulin resistance (response to insulin becomes diminished) in various tissues. Initially, there is an increase in insulin production, but this decreases over time. T2DM most commonly presents in persons older than 45 years, but it increasingly occurs in children, adolescents, and younger adults due to rising levels of obesity, physical inactivity, and energy-dense diets.
Gestational Diabetes Mellitus (GDM)
Hyperglycemia first detected during pregnancy is classified as gestational diabetes mellitus (GDM). Although it can occur anytime during pregnancy, GDM generally affects pregnant women during the second and third trimesters. According to the American Diabetes Association (ADA), GDM complicates 7% of all pregnancies. Women with GDM and their offspring have an increased risk of developing type 2 diabetes mellitus in the future.
Types of Therapies [6]
Therapy for hyperglycemia is dependant upon how much insulin the body is producing, or how well that insulin that is produced is working. The majority of patients with T2DM will be on an oral type of medication. Patients with T1DM will be on a combination of either long-acting insulin with short-acting as a sliding scale, intermediate-acting insulin with short-acting insulin as a sliding scale, combination premixed insulin, or be on an insulin pump.
Hypoglycemia
One of the public health concerns for diabetes mellitus and unintended complications for the reduction in blood glucose levels is hypoglycemia.[1][7][8] Hypoglycemia, by definition, is a plasma glucose concentration below 70 mg/dL, with most patients not having signs or symptoms until the plasma glucose concentrations drop below 55 mg/dL.[9] Low plasma glucose concentration that requires assistance from another individual qualifies as severe hypoglycemia, and by context, all EMS encounters fall into this category.[1][10] There has been an increase in morbidity (poor quality of life, series falls or car accidents, dementia, and hospitalization) and mortality related to severe hypoglycemia.[1]
Based upon 2015 data from NEMSIS, prehospital activation for diabetes-related cases accounts for about 2.3% of all activations, with the primary EMS encounter being hypoglycemia.[11] Patients experiencing severe hypoglycemia or other diabetes-related concerns typically reach out for help by calling 911 who may dispatch a fire department or EMS agency depending on the jurisdiction. Care is then provided by the first on scene provider who may be an emergency medical technician (EMT) intermediate or advanced emergency medical technician (IEMT or AEMT) or paramedic. Treat and release versus transport of patients with hypoglycemia by EMS providers depends on the clinical guidelines or protocols from either the state or regional level by medical directors. It is important to understand that patients with severe hypoglycemia are at a higher risk of having complications related to the hypoglycemic state. Villani et al. indicated that approximately 50% of patients with severe hypoglycemia required transport to the hospital, and of that group, 41.3% were admitted to the hospital.[12][13][14]
One of the first studies on the topic of treating and releasing hypoglycemic patients in the field was "Development and Evaluation of Criteria Allowing Paramedics to Treat and Release Patients Presenting with Hypoglycemia: A Retrospective Study" published in Prehospital and Disaster Medicine in 1991. Their study design proposed five criteria that would allow for appropriate release that would not require additional treatment from prehospital providers to include:
- The patient has a history of type 1 or type 2 diabetes.
- Blood sugar prior to treatment is below 4.4 mmol/L or 80 mg/dL.
- Blood sugar after treatment is equal to or greater than 4.4 mmol/L or 80 mg/dL.
- The patient has a normal mental status within 10 minutes of treatment.
- The patient does not have any other complicating factors that required ED evaluation to such alcohol, chest pain, dyspnea, injuries related to falls, and/or renal dialysis.
A 2016 study by Rostykus et al. reviewed prehospital clinical guidelines for hypoglycemia in 185 EMS agencies in the United States. It revealed that less than half allowed for non-transport of patients with hypoglycemia after the low plasma glucose level was corrected.[15] A study by Moffet et al. looked at hypoglycemic patients treated by EMS in Alameda County from 2013 to 2015 and found that the transport rate was 13.5%. The demographic trends for those non-transported patients were adult patients < 60 years of age, males, finger stick blood glucose levels > 60 mg/dl, and EMS arrival times between 1800 and 0600.[1]